diff options
Diffstat (limited to 'drivers/ntb')
| -rw-r--r-- | drivers/ntb/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/ntb/Makefile | 3 | ||||
| -rw-r--r-- | drivers/ntb/ntb_hw.c | 1545 | ||||
| -rw-r--r-- | drivers/ntb/ntb_hw.h | 247 | ||||
| -rw-r--r-- | drivers/ntb/ntb_regs.h | 159 | ||||
| -rw-r--r-- | drivers/ntb/ntb_transport.c | 1763 | 
6 files changed, 3730 insertions, 0 deletions
diff --git a/drivers/ntb/Kconfig b/drivers/ntb/Kconfig new file mode 100644 index 00000000000..f69df793dbe --- /dev/null +++ b/drivers/ntb/Kconfig @@ -0,0 +1,13 @@ +config NTB +       tristate "Intel Non-Transparent Bridge support" +       depends on PCI +       depends on X86 +       help +        The PCI-E Non-transparent bridge hardware is a point-to-point PCI-E bus +        connecting 2 systems.  When configured, writes to the device's PCI +        mapped memory will be mirrored to a buffer on the remote system.  The +        ntb Linux driver uses this point-to-point communication as a method to +        transfer data from one system to the other. + +        If unsure, say N. + diff --git a/drivers/ntb/Makefile b/drivers/ntb/Makefile new file mode 100644 index 00000000000..15cb59fd354 --- /dev/null +++ b/drivers/ntb/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_NTB) += ntb.o + +ntb-objs := ntb_hw.o ntb_transport.o diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c new file mode 100644 index 00000000000..372e08c4ffe --- /dev/null +++ b/drivers/ntb/ntb_hw.c @@ -0,0 +1,1545 @@ +/* + * This file is provided under a dual BSD/GPLv2 license.  When using or + *   redistributing this file, you may do so under either license. + * + *   GPL LICENSE SUMMARY + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   This program is free software; you can redistribute it and/or modify + *   it under the terms of version 2 of the GNU General Public License as + *   published by the Free Software Foundation. + * + *   BSD LICENSE + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   Redistribution and use in source and binary forms, with or without + *   modification, are permitted provided that the following conditions + *   are met: + * + *     * Redistributions of source code must retain the above copyright + *       notice, this list of conditions and the following disclaimer. + *     * Redistributions in binary form must reproduce the above copy + *       notice, this list of conditions and the following disclaimer in + *       the documentation and/or other materials provided with the + *       distribution. + *     * Neither the name of Intel Corporation nor the names of its + *       contributors may be used to endorse or promote products derived + *       from this software without specific prior written permission. + * + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Intel PCIe NTB Linux driver + * + * Contact Information: + * Jon Mason <jon.mason@intel.com> + */ +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/random.h> +#include <linux/slab.h> +#include "ntb_hw.h" +#include "ntb_regs.h" + +#define NTB_NAME	"Intel(R) PCI-E Non-Transparent Bridge Driver" +#define NTB_VER		"1.0" + +MODULE_DESCRIPTION(NTB_NAME); +MODULE_VERSION(NTB_VER); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Intel Corporation"); + +static bool xeon_errata_workaround = true; +module_param(xeon_errata_workaround, bool, 0644); +MODULE_PARM_DESC(xeon_errata_workaround, "Workaround for the Xeon Errata"); + +enum { +	NTB_CONN_TRANSPARENT = 0, +	NTB_CONN_B2B, +	NTB_CONN_RP, +}; + +enum { +	NTB_DEV_USD = 0, +	NTB_DEV_DSD, +}; + +enum { +	SNB_HW = 0, +	BWD_HW, +}; + +static struct dentry *debugfs_dir; + +#define BWD_LINK_RECOVERY_TIME	500 + +/* Translate memory window 0,1 to BAR 2,4 */ +#define MW_TO_BAR(mw)	(mw * NTB_MAX_NUM_MW + 2) + +static const struct pci_device_id ntb_pci_tbl[] = { +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_BWD)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_JSF)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SNB)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_IVT)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_HSX)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_JSF)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_SNB)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_IVT)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_HSX)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_JSF)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_SNB)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_IVT)}, +	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_HSX)}, +	{0} +}; +MODULE_DEVICE_TABLE(pci, ntb_pci_tbl); + +/** + * ntb_register_event_callback() - register event callback + * @ndev: pointer to ntb_device instance + * @func: callback function to register + * + * This function registers a callback for any HW driver events such as link + * up/down, power management notices and etc. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_register_event_callback(struct ntb_device *ndev, +				void (*func)(void *handle, +					     enum ntb_hw_event event)) +{ +	if (ndev->event_cb) +		return -EINVAL; + +	ndev->event_cb = func; + +	return 0; +} + +/** + * ntb_unregister_event_callback() - unregisters the event callback + * @ndev: pointer to ntb_device instance + * + * This function unregisters the existing callback from transport + */ +void ntb_unregister_event_callback(struct ntb_device *ndev) +{ +	ndev->event_cb = NULL; +} + +static void ntb_irq_work(unsigned long data) +{ +	struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data; +	int rc; + +	rc = db_cb->callback(db_cb->data, db_cb->db_num); +	if (rc) +		tasklet_schedule(&db_cb->irq_work); +	else { +		struct ntb_device *ndev = db_cb->ndev; +		unsigned long mask; + +		mask = readw(ndev->reg_ofs.ldb_mask); +		clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask); +		writew(mask, ndev->reg_ofs.ldb_mask); +	} +} + +/** + * ntb_register_db_callback() - register a callback for doorbell interrupt + * @ndev: pointer to ntb_device instance + * @idx: doorbell index to register callback, zero based + * @data: pointer to be returned to caller with every callback + * @func: callback function to register + * + * This function registers a callback function for the doorbell interrupt + * on the primary side. The function will unmask the doorbell as well to + * allow interrupt. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx, +			     void *data, int (*func)(void *data, int db_num)) +{ +	unsigned long mask; + +	if (idx >= ndev->max_cbs || ndev->db_cb[idx].callback) { +		dev_warn(&ndev->pdev->dev, "Invalid Index.\n"); +		return -EINVAL; +	} + +	ndev->db_cb[idx].callback = func; +	ndev->db_cb[idx].data = data; +	ndev->db_cb[idx].ndev = ndev; + +	tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work, +		     (unsigned long) &ndev->db_cb[idx]); + +	/* unmask interrupt */ +	mask = readw(ndev->reg_ofs.ldb_mask); +	clear_bit(idx * ndev->bits_per_vector, &mask); +	writew(mask, ndev->reg_ofs.ldb_mask); + +	return 0; +} + +/** + * ntb_unregister_db_callback() - unregister a callback for doorbell interrupt + * @ndev: pointer to ntb_device instance + * @idx: doorbell index to register callback, zero based + * + * This function unregisters a callback function for the doorbell interrupt + * on the primary side. The function will also mask the said doorbell. + */ +void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx) +{ +	unsigned long mask; + +	if (idx >= ndev->max_cbs || !ndev->db_cb[idx].callback) +		return; + +	mask = readw(ndev->reg_ofs.ldb_mask); +	set_bit(idx * ndev->bits_per_vector, &mask); +	writew(mask, ndev->reg_ofs.ldb_mask); + +	tasklet_disable(&ndev->db_cb[idx].irq_work); + +	ndev->db_cb[idx].callback = NULL; +} + +/** + * ntb_find_transport() - find the transport pointer + * @transport: pointer to pci device + * + * Given the pci device pointer, return the transport pointer passed in when + * the transport attached when it was inited. + * + * RETURNS: pointer to transport. + */ +void *ntb_find_transport(struct pci_dev *pdev) +{ +	struct ntb_device *ndev = pci_get_drvdata(pdev); +	return ndev->ntb_transport; +} + +/** + * ntb_register_transport() - Register NTB transport with NTB HW driver + * @transport: transport identifier + * + * This function allows a transport to reserve the hardware driver for + * NTB usage. + * + * RETURNS: pointer to ntb_device, NULL on error. + */ +struct ntb_device *ntb_register_transport(struct pci_dev *pdev, void *transport) +{ +	struct ntb_device *ndev = pci_get_drvdata(pdev); + +	if (ndev->ntb_transport) +		return NULL; + +	ndev->ntb_transport = transport; +	return ndev; +} + +/** + * ntb_unregister_transport() - Unregister the transport with the NTB HW driver + * @ndev - ntb_device of the transport to be freed + * + * This function unregisters the transport from the HW driver and performs any + * necessary cleanups. + */ +void ntb_unregister_transport(struct ntb_device *ndev) +{ +	int i; + +	if (!ndev->ntb_transport) +		return; + +	for (i = 0; i < ndev->max_cbs; i++) +		ntb_unregister_db_callback(ndev, i); + +	ntb_unregister_event_callback(ndev); +	ndev->ntb_transport = NULL; +} + +/** + * ntb_write_local_spad() - write to the secondary scratchpad register + * @ndev: pointer to ntb_device instance + * @idx: index to the scratchpad register, 0 based + * @val: the data value to put into the register + * + * This function allows writing of a 32bit value to the indexed scratchpad + * register. This writes over the data mirrored to the local scratchpad register + * by the remote system. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_write_local_spad(struct ntb_device *ndev, unsigned int idx, u32 val) +{ +	if (idx >= ndev->limits.max_spads) +		return -EINVAL; + +	dev_dbg(&ndev->pdev->dev, "Writing %x to local scratch pad index %d\n", +		val, idx); +	writel(val, ndev->reg_ofs.spad_read + idx * 4); + +	return 0; +} + +/** + * ntb_read_local_spad() - read from the primary scratchpad register + * @ndev: pointer to ntb_device instance + * @idx: index to scratchpad register, 0 based + * @val: pointer to 32bit integer for storing the register value + * + * This function allows reading of the 32bit scratchpad register on + * the primary (internal) side.  This allows the local system to read data + * written and mirrored to the scratchpad register by the remote system. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_read_local_spad(struct ntb_device *ndev, unsigned int idx, u32 *val) +{ +	if (idx >= ndev->limits.max_spads) +		return -EINVAL; + +	*val = readl(ndev->reg_ofs.spad_write + idx * 4); +	dev_dbg(&ndev->pdev->dev, +		"Reading %x from local scratch pad index %d\n", *val, idx); + +	return 0; +} + +/** + * ntb_write_remote_spad() - write to the secondary scratchpad register + * @ndev: pointer to ntb_device instance + * @idx: index to the scratchpad register, 0 based + * @val: the data value to put into the register + * + * This function allows writing of a 32bit value to the indexed scratchpad + * register. The register resides on the secondary (external) side.  This allows + * the local system to write data to be mirrored to the remote systems + * scratchpad register. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_write_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 val) +{ +	if (idx >= ndev->limits.max_spads) +		return -EINVAL; + +	dev_dbg(&ndev->pdev->dev, "Writing %x to remote scratch pad index %d\n", +		val, idx); +	writel(val, ndev->reg_ofs.spad_write + idx * 4); + +	return 0; +} + +/** + * ntb_read_remote_spad() - read from the primary scratchpad register + * @ndev: pointer to ntb_device instance + * @idx: index to scratchpad register, 0 based + * @val: pointer to 32bit integer for storing the register value + * + * This function allows reading of the 32bit scratchpad register on + * the primary (internal) side.  This alloows the local system to read the data + * it wrote to be mirrored on the remote system. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_read_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 *val) +{ +	if (idx >= ndev->limits.max_spads) +		return -EINVAL; + +	*val = readl(ndev->reg_ofs.spad_read + idx * 4); +	dev_dbg(&ndev->pdev->dev, +		"Reading %x from remote scratch pad index %d\n", *val, idx); + +	return 0; +} + +/** + * ntb_get_mw_base() - get addr for the NTB memory window + * @ndev: pointer to ntb_device instance + * @mw: memory window number + * + * This function provides the base address of the memory window specified. + * + * RETURNS: address, or NULL on error. + */ +resource_size_t ntb_get_mw_base(struct ntb_device *ndev, unsigned int mw) +{ +	if (mw >= ntb_max_mw(ndev)) +		return 0; + +	return pci_resource_start(ndev->pdev, MW_TO_BAR(mw)); +} + +/** + * ntb_get_mw_vbase() - get virtual addr for the NTB memory window + * @ndev: pointer to ntb_device instance + * @mw: memory window number + * + * This function provides the base virtual address of the memory window + * specified. + * + * RETURNS: pointer to virtual address, or NULL on error. + */ +void __iomem *ntb_get_mw_vbase(struct ntb_device *ndev, unsigned int mw) +{ +	if (mw >= ntb_max_mw(ndev)) +		return NULL; + +	return ndev->mw[mw].vbase; +} + +/** + * ntb_get_mw_size() - return size of NTB memory window + * @ndev: pointer to ntb_device instance + * @mw: memory window number + * + * This function provides the physical size of the memory window specified + * + * RETURNS: the size of the memory window or zero on error + */ +u64 ntb_get_mw_size(struct ntb_device *ndev, unsigned int mw) +{ +	if (mw >= ntb_max_mw(ndev)) +		return 0; + +	return ndev->mw[mw].bar_sz; +} + +/** + * ntb_set_mw_addr - set the memory window address + * @ndev: pointer to ntb_device instance + * @mw: memory window number + * @addr: base address for data + * + * This function sets the base physical address of the memory window.  This + * memory address is where data from the remote system will be transfered into + * or out of depending on how the transport is configured. + */ +void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr) +{ +	if (mw >= ntb_max_mw(ndev)) +		return; + +	dev_dbg(&ndev->pdev->dev, "Writing addr %Lx to BAR %d\n", addr, +		MW_TO_BAR(mw)); + +	ndev->mw[mw].phys_addr = addr; + +	switch (MW_TO_BAR(mw)) { +	case NTB_BAR_23: +		writeq(addr, ndev->reg_ofs.bar2_xlat); +		break; +	case NTB_BAR_45: +		writeq(addr, ndev->reg_ofs.bar4_xlat); +		break; +	} +} + +/** + * ntb_ring_doorbell() - Set the doorbell on the secondary/external side + * @ndev: pointer to ntb_device instance + * @db: doorbell to ring + * + * This function allows triggering of a doorbell on the secondary/external + * side that will initiate an interrupt on the remote host + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +void ntb_ring_doorbell(struct ntb_device *ndev, unsigned int db) +{ +	dev_dbg(&ndev->pdev->dev, "%s: ringing doorbell %d\n", __func__, db); + +	if (ndev->hw_type == BWD_HW) +		writeq((u64) 1 << db, ndev->reg_ofs.rdb); +	else +		writew(((1 << ndev->bits_per_vector) - 1) << +		       (db * ndev->bits_per_vector), ndev->reg_ofs.rdb); +} + +static void bwd_recover_link(struct ntb_device *ndev) +{ +	u32 status; + +	/* Driver resets the NTB ModPhy lanes - magic! */ +	writeb(0xe0, ndev->reg_base + BWD_MODPHY_PCSREG6); +	writeb(0x40, ndev->reg_base + BWD_MODPHY_PCSREG4); +	writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG4); +	writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG6); + +	/* Driver waits 100ms to allow the NTB ModPhy to settle */ +	msleep(100); + +	/* Clear AER Errors, write to clear */ +	status = readl(ndev->reg_base + BWD_ERRCORSTS_OFFSET); +	dev_dbg(&ndev->pdev->dev, "ERRCORSTS = %x\n", status); +	status &= PCI_ERR_COR_REP_ROLL; +	writel(status, ndev->reg_base + BWD_ERRCORSTS_OFFSET); + +	/* Clear unexpected electrical idle event in LTSSM, write to clear */ +	status = readl(ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET); +	dev_dbg(&ndev->pdev->dev, "LTSSMERRSTS0 = %x\n", status); +	status |= BWD_LTSSMERRSTS0_UNEXPECTEDEI; +	writel(status, ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET); + +	/* Clear DeSkew Buffer error, write to clear */ +	status = readl(ndev->reg_base + BWD_DESKEWSTS_OFFSET); +	dev_dbg(&ndev->pdev->dev, "DESKEWSTS = %x\n", status); +	status |= BWD_DESKEWSTS_DBERR; +	writel(status, ndev->reg_base + BWD_DESKEWSTS_OFFSET); + +	status = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET); +	dev_dbg(&ndev->pdev->dev, "IBSTERRRCRVSTS0 = %x\n", status); +	status &= BWD_IBIST_ERR_OFLOW; +	writel(status, ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET); + +	/* Releases the NTB state machine to allow the link to retrain */ +	status = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET); +	dev_dbg(&ndev->pdev->dev, "LTSSMSTATEJMP = %x\n", status); +	status &= ~BWD_LTSSMSTATEJMP_FORCEDETECT; +	writel(status, ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET); +} + +static void ntb_link_event(struct ntb_device *ndev, int link_state) +{ +	unsigned int event; + +	if (ndev->link_status == link_state) +		return; + +	if (link_state == NTB_LINK_UP) { +		u16 status; + +		dev_info(&ndev->pdev->dev, "Link Up\n"); +		ndev->link_status = NTB_LINK_UP; +		event = NTB_EVENT_HW_LINK_UP; + +		if (ndev->hw_type == BWD_HW || +		    ndev->conn_type == NTB_CONN_TRANSPARENT) +			status = readw(ndev->reg_ofs.lnk_stat); +		else { +			int rc = pci_read_config_word(ndev->pdev, +						      SNB_LINK_STATUS_OFFSET, +						      &status); +			if (rc) +				return; +		} + +		ndev->link_width = (status & NTB_LINK_WIDTH_MASK) >> 4; +		ndev->link_speed = (status & NTB_LINK_SPEED_MASK); +		dev_info(&ndev->pdev->dev, "Link Width %d, Link Speed %d\n", +			 ndev->link_width, ndev->link_speed); +	} else { +		dev_info(&ndev->pdev->dev, "Link Down\n"); +		ndev->link_status = NTB_LINK_DOWN; +		event = NTB_EVENT_HW_LINK_DOWN; +		/* Don't modify link width/speed, we need it in link recovery */ +	} + +	/* notify the upper layer if we have an event change */ +	if (ndev->event_cb) +		ndev->event_cb(ndev->ntb_transport, event); +} + +static int ntb_link_status(struct ntb_device *ndev) +{ +	int link_state; + +	if (ndev->hw_type == BWD_HW) { +		u32 ntb_cntl; + +		ntb_cntl = readl(ndev->reg_ofs.lnk_cntl); +		if (ntb_cntl & BWD_CNTL_LINK_DOWN) +			link_state = NTB_LINK_DOWN; +		else +			link_state = NTB_LINK_UP; +	} else { +		u16 status; +		int rc; + +		rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET, +					  &status); +		if (rc) +			return rc; + +		if (status & NTB_LINK_STATUS_ACTIVE) +			link_state = NTB_LINK_UP; +		else +			link_state = NTB_LINK_DOWN; +	} + +	ntb_link_event(ndev, link_state); + +	return 0; +} + +static void bwd_link_recovery(struct work_struct *work) +{ +	struct ntb_device *ndev = container_of(work, struct ntb_device, +					       lr_timer.work); +	u32 status32; + +	bwd_recover_link(ndev); +	/* There is a potential race between the 2 NTB devices recovering at the +	 * same time.  If the times are the same, the link will not recover and +	 * the driver will be stuck in this loop forever.  Add a random interval +	 * to the recovery time to prevent this race. +	 */ +	msleep(BWD_LINK_RECOVERY_TIME + prandom_u32() % BWD_LINK_RECOVERY_TIME); + +	status32 = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET); +	if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT) +		goto retry; + +	status32 = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET); +	if (status32 & BWD_IBIST_ERR_OFLOW) +		goto retry; + +	status32 = readl(ndev->reg_ofs.lnk_cntl); +	if (!(status32 & BWD_CNTL_LINK_DOWN)) { +		unsigned char speed, width; +		u16 status16; + +		status16 = readw(ndev->reg_ofs.lnk_stat); +		width = (status16 & NTB_LINK_WIDTH_MASK) >> 4; +		speed = (status16 & NTB_LINK_SPEED_MASK); +		if (ndev->link_width != width || ndev->link_speed != speed) +			goto retry; +	} + +	schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT); +	return; + +retry: +	schedule_delayed_work(&ndev->lr_timer, NTB_HB_TIMEOUT); +} + +/* BWD doesn't have link status interrupt, poll on that platform */ +static void bwd_link_poll(struct work_struct *work) +{ +	struct ntb_device *ndev = container_of(work, struct ntb_device, +					       hb_timer.work); +	unsigned long ts = jiffies; + +	/* If we haven't gotten an interrupt in a while, check the BWD link +	 * status bit +	 */ +	if (ts > ndev->last_ts + NTB_HB_TIMEOUT) { +		int rc = ntb_link_status(ndev); +		if (rc) +			dev_err(&ndev->pdev->dev, +				"Error determining link status\n"); + +		/* Check to see if a link error is the cause of the link down */ +		if (ndev->link_status == NTB_LINK_DOWN) { +			u32 status32 = readl(ndev->reg_base + +					     BWD_LTSSMSTATEJMP_OFFSET); +			if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT) { +				schedule_delayed_work(&ndev->lr_timer, 0); +				return; +			} +		} +	} + +	schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT); +} + +static int ntb_xeon_setup(struct ntb_device *ndev) +{ +	int rc; +	u8 val; + +	ndev->hw_type = SNB_HW; + +	rc = pci_read_config_byte(ndev->pdev, NTB_PPD_OFFSET, &val); +	if (rc) +		return rc; + +	if (val & SNB_PPD_DEV_TYPE) +		ndev->dev_type = NTB_DEV_USD; +	else +		ndev->dev_type = NTB_DEV_DSD; + +	switch (val & SNB_PPD_CONN_TYPE) { +	case NTB_CONN_B2B: +		dev_info(&ndev->pdev->dev, "Conn Type = B2B\n"); +		ndev->conn_type = NTB_CONN_B2B; +		ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET; +		ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET; +		ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET; +		ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET; +		ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET; +		ndev->limits.max_spads = SNB_MAX_B2B_SPADS; + +		/* There is a Xeon hardware errata related to writes to +		 * SDOORBELL or B2BDOORBELL in conjunction with inbound access +		 * to NTB MMIO Space, which may hang the system.  To workaround +		 * this use the second memory window to access the interrupt and +		 * scratch pad registers on the remote system. +		 */ +		if (xeon_errata_workaround) { +			if (!ndev->mw[1].bar_sz) +				return -EINVAL; + +			ndev->limits.max_mw = SNB_ERRATA_MAX_MW; +			ndev->limits.max_db_bits = SNB_MAX_DB_BITS; +			ndev->reg_ofs.spad_write = ndev->mw[1].vbase + +						   SNB_SPAD_OFFSET; +			ndev->reg_ofs.rdb = ndev->mw[1].vbase + +					    SNB_PDOORBELL_OFFSET; + +			/* Set the Limit register to 4k, the minimum size, to +			 * prevent an illegal access +			 */ +			writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base + +			       SNB_PBAR4LMT_OFFSET); +			/* HW errata on the Limit registers.  They can only be +			 * written when the base register is 4GB aligned and +			 * < 32bit.  This should already be the case based on +			 * the driver defaults, but write the Limit registers +			 * first just in case. +			 */ +		} else { +			ndev->limits.max_mw = SNB_MAX_MW; + +			/* HW Errata on bit 14 of b2bdoorbell register.  Writes +			 * will not be mirrored to the remote system.  Shrink +			 * the number of bits by one, since bit 14 is the last +			 * bit. +			 */ +			ndev->limits.max_db_bits = SNB_MAX_DB_BITS - 1; +			ndev->reg_ofs.spad_write = ndev->reg_base + +						   SNB_B2B_SPAD_OFFSET; +			ndev->reg_ofs.rdb = ndev->reg_base + +					    SNB_B2B_DOORBELL_OFFSET; + +			/* Disable the Limit register, just incase it is set to +			 * something silly +			 */ +			writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET); +			/* HW errata on the Limit registers.  They can only be +			 * written when the base register is 4GB aligned and +			 * < 32bit.  This should already be the case based on +			 * the driver defaults, but write the Limit registers +			 * first just in case. +			 */ +		} + +		/* The Xeon errata workaround requires setting SBAR Base +		 * addresses to known values, so that the PBAR XLAT can be +		 * pointed at SBAR0 of the remote system. +		 */ +		if (ndev->dev_type == NTB_DEV_USD) { +			writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + +			       SNB_PBAR2XLAT_OFFSET); +			if (xeon_errata_workaround) +				writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base + +				       SNB_PBAR4XLAT_OFFSET); +			else { +				writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base + +				       SNB_PBAR4XLAT_OFFSET); +				/* B2B_XLAT_OFFSET is a 64bit register, but can +				 * only take 32bit writes +				 */ +				writel(SNB_MBAR01_DSD_ADDR & 0xffffffff, +				       ndev->reg_base + SNB_B2B_XLAT_OFFSETL); +				writel(SNB_MBAR01_DSD_ADDR >> 32, +				       ndev->reg_base + SNB_B2B_XLAT_OFFSETU); +			} + +			writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + +			       SNB_SBAR0BASE_OFFSET); +			writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + +			       SNB_SBAR2BASE_OFFSET); +			writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + +			       SNB_SBAR4BASE_OFFSET); +		} else { +			writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base + +			       SNB_PBAR2XLAT_OFFSET); +			if (xeon_errata_workaround) +				writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base + +				       SNB_PBAR4XLAT_OFFSET); +			else { +				writeq(SNB_MBAR45_USD_ADDR, ndev->reg_base + +				       SNB_PBAR4XLAT_OFFSET); +				/* B2B_XLAT_OFFSET is a 64bit register, but can +				 * only take 32bit writes +				 */ +				writel(SNB_MBAR01_USD_ADDR & 0xffffffff, +				       ndev->reg_base + SNB_B2B_XLAT_OFFSETL); +				writel(SNB_MBAR01_USD_ADDR >> 32, +				       ndev->reg_base + SNB_B2B_XLAT_OFFSETU); +			} +			writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base + +			       SNB_SBAR0BASE_OFFSET); +			writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base + +			       SNB_SBAR2BASE_OFFSET); +			writeq(SNB_MBAR45_DSD_ADDR, ndev->reg_base + +			       SNB_SBAR4BASE_OFFSET); +		} +		break; +	case NTB_CONN_RP: +		dev_info(&ndev->pdev->dev, "Conn Type = RP\n"); +		ndev->conn_type = NTB_CONN_RP; + +		if (xeon_errata_workaround) { +			dev_err(&ndev->pdev->dev, +				"NTB-RP disabled due to hardware errata.  To disregard this warning and potentially lock-up the system, add the parameter 'xeon_errata_workaround=0'.\n"); +			return -EINVAL; +		} + +		/* Scratch pads need to have exclusive access from the primary +		 * or secondary side.  Halve the num spads so that each side can +		 * have an equal amount. +		 */ +		ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2; +		ndev->limits.max_db_bits = SNB_MAX_DB_BITS; +		/* Note: The SDOORBELL is the cause of the errata.  You REALLY +		 * don't want to touch it. +		 */ +		ndev->reg_ofs.rdb = ndev->reg_base + SNB_SDOORBELL_OFFSET; +		ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET; +		ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET; +		/* Offset the start of the spads to correspond to whether it is +		 * primary or secondary +		 */ +		ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET + +					   ndev->limits.max_spads * 4; +		ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET; +		ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET; +		ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET; +		ndev->limits.max_mw = SNB_MAX_MW; +		break; +	case NTB_CONN_TRANSPARENT: +		dev_info(&ndev->pdev->dev, "Conn Type = TRANSPARENT\n"); +		ndev->conn_type = NTB_CONN_TRANSPARENT; +		/* Scratch pads need to have exclusive access from the primary +		 * or secondary side.  Halve the num spads so that each side can +		 * have an equal amount. +		 */ +		ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2; +		ndev->limits.max_db_bits = SNB_MAX_DB_BITS; +		ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET; +		ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET; +		ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET; +		ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET; +		/* Offset the start of the spads to correspond to whether it is +		 * primary or secondary +		 */ +		ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET + +					  ndev->limits.max_spads * 4; +		ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_PBAR2XLAT_OFFSET; +		ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_PBAR4XLAT_OFFSET; + +		ndev->limits.max_mw = SNB_MAX_MW; +		break; +	default: +		/* Most likely caused by the remote NTB-RP device not being +		 * configured +		 */ +		dev_err(&ndev->pdev->dev, "Unknown PPD %x\n", val); +		return -EINVAL; +	} + +	ndev->reg_ofs.lnk_cntl = ndev->reg_base + SNB_NTBCNTL_OFFSET; +	ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET; +	ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET; + +	ndev->limits.msix_cnt = SNB_MSIX_CNT; +	ndev->bits_per_vector = SNB_DB_BITS_PER_VEC; + +	return 0; +} + +static int ntb_bwd_setup(struct ntb_device *ndev) +{ +	int rc; +	u32 val; + +	ndev->hw_type = BWD_HW; + +	rc = pci_read_config_dword(ndev->pdev, NTB_PPD_OFFSET, &val); +	if (rc) +		return rc; + +	switch ((val & BWD_PPD_CONN_TYPE) >> 8) { +	case NTB_CONN_B2B: +		ndev->conn_type = NTB_CONN_B2B; +		break; +	case NTB_CONN_RP: +	default: +		dev_err(&ndev->pdev->dev, "Unsupported NTB configuration\n"); +		return -EINVAL; +	} + +	if (val & BWD_PPD_DEV_TYPE) +		ndev->dev_type = NTB_DEV_DSD; +	else +		ndev->dev_type = NTB_DEV_USD; + +	/* Initiate PCI-E link training */ +	rc = pci_write_config_dword(ndev->pdev, NTB_PPD_OFFSET, +				    val | BWD_PPD_INIT_LINK); +	if (rc) +		return rc; + +	ndev->reg_ofs.ldb = ndev->reg_base + BWD_PDOORBELL_OFFSET; +	ndev->reg_ofs.ldb_mask = ndev->reg_base + BWD_PDBMSK_OFFSET; +	ndev->reg_ofs.rdb = ndev->reg_base + BWD_B2B_DOORBELL_OFFSET; +	ndev->reg_ofs.bar2_xlat = ndev->reg_base + BWD_SBAR2XLAT_OFFSET; +	ndev->reg_ofs.bar4_xlat = ndev->reg_base + BWD_SBAR4XLAT_OFFSET; +	ndev->reg_ofs.lnk_cntl = ndev->reg_base + BWD_NTBCNTL_OFFSET; +	ndev->reg_ofs.lnk_stat = ndev->reg_base + BWD_LINK_STATUS_OFFSET; +	ndev->reg_ofs.spad_read = ndev->reg_base + BWD_SPAD_OFFSET; +	ndev->reg_ofs.spad_write = ndev->reg_base + BWD_B2B_SPAD_OFFSET; +	ndev->reg_ofs.spci_cmd = ndev->reg_base + BWD_PCICMD_OFFSET; +	ndev->limits.max_mw = BWD_MAX_MW; +	ndev->limits.max_spads = BWD_MAX_SPADS; +	ndev->limits.max_db_bits = BWD_MAX_DB_BITS; +	ndev->limits.msix_cnt = BWD_MSIX_CNT; +	ndev->bits_per_vector = BWD_DB_BITS_PER_VEC; + +	/* Since bwd doesn't have a link interrupt, setup a poll timer */ +	INIT_DELAYED_WORK(&ndev->hb_timer, bwd_link_poll); +	INIT_DELAYED_WORK(&ndev->lr_timer, bwd_link_recovery); +	schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT); + +	return 0; +} + +static int ntb_device_setup(struct ntb_device *ndev) +{ +	int rc; + +	switch (ndev->pdev->device) { +	case PCI_DEVICE_ID_INTEL_NTB_SS_JSF: +	case PCI_DEVICE_ID_INTEL_NTB_SS_SNB: +	case PCI_DEVICE_ID_INTEL_NTB_SS_IVT: +	case PCI_DEVICE_ID_INTEL_NTB_SS_HSX: +	case PCI_DEVICE_ID_INTEL_NTB_PS_JSF: +	case PCI_DEVICE_ID_INTEL_NTB_PS_SNB: +	case PCI_DEVICE_ID_INTEL_NTB_PS_IVT: +	case PCI_DEVICE_ID_INTEL_NTB_PS_HSX: +	case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF: +	case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB: +	case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT: +	case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX: +		rc = ntb_xeon_setup(ndev); +		break; +	case PCI_DEVICE_ID_INTEL_NTB_B2B_BWD: +		rc = ntb_bwd_setup(ndev); +		break; +	default: +		rc = -ENODEV; +	} + +	if (rc) +		return rc; + +	dev_info(&ndev->pdev->dev, "Device Type = %s\n", +		 ndev->dev_type == NTB_DEV_USD ? "USD/DSP" : "DSD/USP"); + +	if (ndev->conn_type == NTB_CONN_B2B) +		/* Enable Bus Master and Memory Space on the secondary side */ +		writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER, +		       ndev->reg_ofs.spci_cmd); + +	return 0; +} + +static void ntb_device_free(struct ntb_device *ndev) +{ +	if (ndev->hw_type == BWD_HW) { +		cancel_delayed_work_sync(&ndev->hb_timer); +		cancel_delayed_work_sync(&ndev->lr_timer); +	} +} + +static irqreturn_t bwd_callback_msix_irq(int irq, void *data) +{ +	struct ntb_db_cb *db_cb = data; +	struct ntb_device *ndev = db_cb->ndev; +	unsigned long mask; + +	dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq, +		db_cb->db_num); + +	mask = readw(ndev->reg_ofs.ldb_mask); +	set_bit(db_cb->db_num * ndev->bits_per_vector, &mask); +	writew(mask, ndev->reg_ofs.ldb_mask); + +	tasklet_schedule(&db_cb->irq_work); + +	/* No need to check for the specific HB irq, any interrupt means +	 * we're connected. +	 */ +	ndev->last_ts = jiffies; + +	writeq((u64) 1 << db_cb->db_num, ndev->reg_ofs.ldb); + +	return IRQ_HANDLED; +} + +static irqreturn_t xeon_callback_msix_irq(int irq, void *data) +{ +	struct ntb_db_cb *db_cb = data; +	struct ntb_device *ndev = db_cb->ndev; +	unsigned long mask; + +	dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq, +		db_cb->db_num); + +	mask = readw(ndev->reg_ofs.ldb_mask); +	set_bit(db_cb->db_num * ndev->bits_per_vector, &mask); +	writew(mask, ndev->reg_ofs.ldb_mask); + +	tasklet_schedule(&db_cb->irq_work); + +	/* On Sandybridge, there are 16 bits in the interrupt register +	 * but only 4 vectors.  So, 5 bits are assigned to the first 3 +	 * vectors, with the 4th having a single bit for link +	 * interrupts. +	 */ +	writew(((1 << ndev->bits_per_vector) - 1) << +	       (db_cb->db_num * ndev->bits_per_vector), ndev->reg_ofs.ldb); + +	return IRQ_HANDLED; +} + +/* Since we do not have a HW doorbell in BWD, this is only used in JF/JT */ +static irqreturn_t xeon_event_msix_irq(int irq, void *dev) +{ +	struct ntb_device *ndev = dev; +	int rc; + +	dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for Events\n", irq); + +	rc = ntb_link_status(ndev); +	if (rc) +		dev_err(&ndev->pdev->dev, "Error determining link status\n"); + +	/* bit 15 is always the link bit */ +	writew(1 << SNB_LINK_DB, ndev->reg_ofs.ldb); + +	return IRQ_HANDLED; +} + +static irqreturn_t ntb_interrupt(int irq, void *dev) +{ +	struct ntb_device *ndev = dev; +	unsigned int i = 0; + +	if (ndev->hw_type == BWD_HW) { +		u64 ldb = readq(ndev->reg_ofs.ldb); + +		dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %Lx\n", irq, ldb); + +		while (ldb) { +			i = __ffs(ldb); +			ldb &= ldb - 1; +			bwd_callback_msix_irq(irq, &ndev->db_cb[i]); +		} +	} else { +		u16 ldb = readw(ndev->reg_ofs.ldb); + +		dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %x\n", irq, ldb); + +		if (ldb & SNB_DB_HW_LINK) { +			xeon_event_msix_irq(irq, dev); +			ldb &= ~SNB_DB_HW_LINK; +		} + +		while (ldb) { +			i = __ffs(ldb); +			ldb &= ldb - 1; +			xeon_callback_msix_irq(irq, &ndev->db_cb[i]); +		} +	} + +	return IRQ_HANDLED; +} + +static int ntb_setup_snb_msix(struct ntb_device *ndev, int msix_entries) +{ +	struct pci_dev *pdev = ndev->pdev; +	struct msix_entry *msix; +	int rc, i; + +	if (msix_entries < ndev->limits.msix_cnt) +		return -ENOSPC; + +	rc = pci_enable_msix_exact(pdev, ndev->msix_entries, msix_entries); +	if (rc < 0) +		return rc; + +	for (i = 0; i < msix_entries; i++) { +		msix = &ndev->msix_entries[i]; +		WARN_ON(!msix->vector); + +		if (i == msix_entries - 1) { +			rc = request_irq(msix->vector, +					 xeon_event_msix_irq, 0, +					 "ntb-event-msix", ndev); +			if (rc) +				goto err; +		} else { +			rc = request_irq(msix->vector, +					 xeon_callback_msix_irq, 0, +					 "ntb-callback-msix", +					 &ndev->db_cb[i]); +			if (rc) +				goto err; +		} +	} + +	ndev->num_msix = msix_entries; +	ndev->max_cbs = msix_entries - 1; + +	return 0; + +err: +	while (--i >= 0) { +		/* Code never reaches here for entry nr 'ndev->num_msix - 1' */ +		msix = &ndev->msix_entries[i]; +		free_irq(msix->vector, &ndev->db_cb[i]); +	} + +	pci_disable_msix(pdev); +	ndev->num_msix = 0; + +	return rc; +} + +static int ntb_setup_bwd_msix(struct ntb_device *ndev, int msix_entries) +{ +	struct pci_dev *pdev = ndev->pdev; +	struct msix_entry *msix; +	int rc, i; + +	msix_entries = pci_enable_msix_range(pdev, ndev->msix_entries, +					     1, msix_entries); +	if (msix_entries < 0) +		return msix_entries; + +	for (i = 0; i < msix_entries; i++) { +		msix = &ndev->msix_entries[i]; +		WARN_ON(!msix->vector); + +		rc = request_irq(msix->vector, bwd_callback_msix_irq, 0, +				 "ntb-callback-msix", &ndev->db_cb[i]); +		if (rc) +			goto err; +	} + +	ndev->num_msix = msix_entries; +	ndev->max_cbs = msix_entries; + +	return 0; + +err: +	while (--i >= 0) +		free_irq(msix->vector, &ndev->db_cb[i]); + +	pci_disable_msix(pdev); +	ndev->num_msix = 0; + +	return rc; +} + +static int ntb_setup_msix(struct ntb_device *ndev) +{ +	struct pci_dev *pdev = ndev->pdev; +	int msix_entries; +	int rc, i; + +	msix_entries = pci_msix_vec_count(pdev); +	if (msix_entries < 0) { +		rc = msix_entries; +		goto err; +	} else if (msix_entries > ndev->limits.msix_cnt) { +		rc = -EINVAL; +		goto err; +	} + +	ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries, +				     GFP_KERNEL); +	if (!ndev->msix_entries) { +		rc = -ENOMEM; +		goto err; +	} + +	for (i = 0; i < msix_entries; i++) +		ndev->msix_entries[i].entry = i; + +	if (ndev->hw_type == BWD_HW) +		rc = ntb_setup_bwd_msix(ndev, msix_entries); +	else +		rc = ntb_setup_snb_msix(ndev, msix_entries); +	if (rc) +		goto err1; + +	return 0; + +err1: +	kfree(ndev->msix_entries); +err: +	dev_err(&pdev->dev, "Error allocating MSI-X interrupt\n"); +	return rc; +} + +static int ntb_setup_msi(struct ntb_device *ndev) +{ +	struct pci_dev *pdev = ndev->pdev; +	int rc; + +	rc = pci_enable_msi(pdev); +	if (rc) +		return rc; + +	rc = request_irq(pdev->irq, ntb_interrupt, 0, "ntb-msi", ndev); +	if (rc) { +		pci_disable_msi(pdev); +		dev_err(&pdev->dev, "Error allocating MSI interrupt\n"); +		return rc; +	} + +	return 0; +} + +static int ntb_setup_intx(struct ntb_device *ndev) +{ +	struct pci_dev *pdev = ndev->pdev; +	int rc; + +	pci_msi_off(pdev); + +	/* Verify intx is enabled */ +	pci_intx(pdev, 1); + +	rc = request_irq(pdev->irq, ntb_interrupt, IRQF_SHARED, "ntb-intx", +			 ndev); +	if (rc) +		return rc; + +	return 0; +} + +static int ntb_setup_interrupts(struct ntb_device *ndev) +{ +	int rc; + +	/* On BWD, disable all interrupts.  On SNB, disable all but Link +	 * Interrupt.  The rest will be unmasked as callbacks are registered. +	 */ +	if (ndev->hw_type == BWD_HW) +		writeq(~0, ndev->reg_ofs.ldb_mask); +	else { +		u16 var = 1 << SNB_LINK_DB; +		writew(~var, ndev->reg_ofs.ldb_mask); +	} + +	rc = ntb_setup_msix(ndev); +	if (!rc) +		goto done; + +	ndev->bits_per_vector = 1; +	ndev->max_cbs = ndev->limits.max_db_bits; + +	rc = ntb_setup_msi(ndev); +	if (!rc) +		goto done; + +	rc = ntb_setup_intx(ndev); +	if (rc) { +		dev_err(&ndev->pdev->dev, "no usable interrupts\n"); +		return rc; +	} + +done: +	return 0; +} + +static void ntb_free_interrupts(struct ntb_device *ndev) +{ +	struct pci_dev *pdev = ndev->pdev; + +	/* mask interrupts */ +	if (ndev->hw_type == BWD_HW) +		writeq(~0, ndev->reg_ofs.ldb_mask); +	else +		writew(~0, ndev->reg_ofs.ldb_mask); + +	if (ndev->num_msix) { +		struct msix_entry *msix; +		u32 i; + +		for (i = 0; i < ndev->num_msix; i++) { +			msix = &ndev->msix_entries[i]; +			if (ndev->hw_type != BWD_HW && i == ndev->num_msix - 1) +				free_irq(msix->vector, ndev); +			else +				free_irq(msix->vector, &ndev->db_cb[i]); +		} +		pci_disable_msix(pdev); +		kfree(ndev->msix_entries); +	} else { +		free_irq(pdev->irq, ndev); + +		if (pci_dev_msi_enabled(pdev)) +			pci_disable_msi(pdev); +	} +} + +static int ntb_create_callbacks(struct ntb_device *ndev) +{ +	int i; + +	/* Chicken-egg issue.  We won't know how many callbacks are necessary +	 * until we see how many MSI-X vectors we get, but these pointers need +	 * to be passed into the MSI-X register function.  So, we allocate the +	 * max, knowing that they might not all be used, to work around this. +	 */ +	ndev->db_cb = kcalloc(ndev->limits.max_db_bits, +			      sizeof(struct ntb_db_cb), +			      GFP_KERNEL); +	if (!ndev->db_cb) +		return -ENOMEM; + +	for (i = 0; i < ndev->limits.max_db_bits; i++) { +		ndev->db_cb[i].db_num = i; +		ndev->db_cb[i].ndev = ndev; +	} + +	return 0; +} + +static void ntb_free_callbacks(struct ntb_device *ndev) +{ +	int i; + +	for (i = 0; i < ndev->limits.max_db_bits; i++) +		ntb_unregister_db_callback(ndev, i); + +	kfree(ndev->db_cb); +} + +static void ntb_setup_debugfs(struct ntb_device *ndev) +{ +	if (!debugfs_initialized()) +		return; + +	if (!debugfs_dir) +		debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL); + +	ndev->debugfs_dir = debugfs_create_dir(pci_name(ndev->pdev), +					       debugfs_dir); +} + +static void ntb_free_debugfs(struct ntb_device *ndev) +{ +	debugfs_remove_recursive(ndev->debugfs_dir); + +	if (debugfs_dir && simple_empty(debugfs_dir)) { +		debugfs_remove_recursive(debugfs_dir); +		debugfs_dir = NULL; +	} +} + +static void ntb_hw_link_up(struct ntb_device *ndev) +{ +	if (ndev->conn_type == NTB_CONN_TRANSPARENT) +		ntb_link_event(ndev, NTB_LINK_UP); +	else { +		u32 ntb_cntl; + +		/* Let's bring the NTB link up */ +		ntb_cntl = readl(ndev->reg_ofs.lnk_cntl); +		ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK); +		ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP; +		ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP; +		writel(ntb_cntl, ndev->reg_ofs.lnk_cntl); +	} +} + +static void ntb_hw_link_down(struct ntb_device *ndev) +{ +	u32 ntb_cntl; + +	if (ndev->conn_type == NTB_CONN_TRANSPARENT) { +		ntb_link_event(ndev, NTB_LINK_DOWN); +		return; +	} + +	/* Bring NTB link down */ +	ntb_cntl = readl(ndev->reg_ofs.lnk_cntl); +	ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP); +	ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP); +	ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK; +	writel(ntb_cntl, ndev->reg_ofs.lnk_cntl); +} + +static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ +	struct ntb_device *ndev; +	int rc, i; + +	ndev = kzalloc(sizeof(struct ntb_device), GFP_KERNEL); +	if (!ndev) +		return -ENOMEM; + +	ndev->pdev = pdev; +	ndev->link_status = NTB_LINK_DOWN; +	pci_set_drvdata(pdev, ndev); +	ntb_setup_debugfs(ndev); + +	rc = pci_enable_device(pdev); +	if (rc) +		goto err; + +	pci_set_master(ndev->pdev); + +	rc = pci_request_selected_regions(pdev, NTB_BAR_MASK, KBUILD_MODNAME); +	if (rc) +		goto err1; + +	ndev->reg_base = pci_ioremap_bar(pdev, NTB_BAR_MMIO); +	if (!ndev->reg_base) { +		dev_warn(&pdev->dev, "Cannot remap BAR 0\n"); +		rc = -EIO; +		goto err2; +	} + +	for (i = 0; i < NTB_MAX_NUM_MW; i++) { +		ndev->mw[i].bar_sz = pci_resource_len(pdev, MW_TO_BAR(i)); +		ndev->mw[i].vbase = +		    ioremap_wc(pci_resource_start(pdev, MW_TO_BAR(i)), +			       ndev->mw[i].bar_sz); +		dev_info(&pdev->dev, "MW %d size %llu\n", i, +			 (unsigned long long) ndev->mw[i].bar_sz); +		if (!ndev->mw[i].vbase) { +			dev_warn(&pdev->dev, "Cannot remap BAR %d\n", +				 MW_TO_BAR(i)); +			rc = -EIO; +			goto err3; +		} +	} + +	rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64)); +	if (rc) { +		rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); +		if (rc) +			goto err3; + +		dev_warn(&pdev->dev, "Cannot DMA highmem\n"); +	} + +	rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)); +	if (rc) { +		rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)); +		if (rc) +			goto err3; + +		dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n"); +	} + +	rc = ntb_device_setup(ndev); +	if (rc) +		goto err3; + +	rc = ntb_create_callbacks(ndev); +	if (rc) +		goto err4; + +	rc = ntb_setup_interrupts(ndev); +	if (rc) +		goto err5; + +	/* The scratchpad registers keep the values between rmmod/insmod, +	 * blast them now +	 */ +	for (i = 0; i < ndev->limits.max_spads; i++) { +		ntb_write_local_spad(ndev, i, 0); +		ntb_write_remote_spad(ndev, i, 0); +	} + +	rc = ntb_transport_init(pdev); +	if (rc) +		goto err6; + +	ntb_hw_link_up(ndev); + +	return 0; + +err6: +	ntb_free_interrupts(ndev); +err5: +	ntb_free_callbacks(ndev); +err4: +	ntb_device_free(ndev); +err3: +	for (i--; i >= 0; i--) +		iounmap(ndev->mw[i].vbase); +	iounmap(ndev->reg_base); +err2: +	pci_release_selected_regions(pdev, NTB_BAR_MASK); +err1: +	pci_disable_device(pdev); +err: +	ntb_free_debugfs(ndev); +	kfree(ndev); + +	dev_err(&pdev->dev, "Error loading %s module\n", KBUILD_MODNAME); +	return rc; +} + +static void ntb_pci_remove(struct pci_dev *pdev) +{ +	struct ntb_device *ndev = pci_get_drvdata(pdev); +	int i; + +	ntb_hw_link_down(ndev); + +	ntb_transport_free(ndev->ntb_transport); + +	ntb_free_interrupts(ndev); +	ntb_free_callbacks(ndev); +	ntb_device_free(ndev); + +	for (i = 0; i < NTB_MAX_NUM_MW; i++) +		iounmap(ndev->mw[i].vbase); + +	iounmap(ndev->reg_base); +	pci_release_selected_regions(pdev, NTB_BAR_MASK); +	pci_disable_device(pdev); +	ntb_free_debugfs(ndev); +	kfree(ndev); +} + +static struct pci_driver ntb_pci_driver = { +	.name = KBUILD_MODNAME, +	.id_table = ntb_pci_tbl, +	.probe = ntb_pci_probe, +	.remove = ntb_pci_remove, +}; +module_pci_driver(ntb_pci_driver); diff --git a/drivers/ntb/ntb_hw.h b/drivers/ntb/ntb_hw.h new file mode 100644 index 00000000000..465517b7393 --- /dev/null +++ b/drivers/ntb/ntb_hw.h @@ -0,0 +1,247 @@ +/* + * This file is provided under a dual BSD/GPLv2 license.  When using or + *   redistributing this file, you may do so under either license. + * + *   GPL LICENSE SUMMARY + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   This program is free software; you can redistribute it and/or modify + *   it under the terms of version 2 of the GNU General Public License as + *   published by the Free Software Foundation. + * + *   BSD LICENSE + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   Redistribution and use in source and binary forms, with or without + *   modification, are permitted provided that the following conditions + *   are met: + * + *     * Redistributions of source code must retain the above copyright + *       notice, this list of conditions and the following disclaimer. + *     * Redistributions in binary form must reproduce the above copy + *       notice, this list of conditions and the following disclaimer in + *       the documentation and/or other materials provided with the + *       distribution. + *     * Neither the name of Intel Corporation nor the names of its + *       contributors may be used to endorse or promote products derived + *       from this software without specific prior written permission. + * + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Intel PCIe NTB Linux driver + * + * Contact Information: + * Jon Mason <jon.mason@intel.com> + */ +#include <linux/ntb.h> + +#define PCI_DEVICE_ID_INTEL_NTB_B2B_JSF		0x3725 +#define PCI_DEVICE_ID_INTEL_NTB_PS_JSF		0x3726 +#define PCI_DEVICE_ID_INTEL_NTB_SS_JSF		0x3727 +#define PCI_DEVICE_ID_INTEL_NTB_B2B_SNB		0x3C0D +#define PCI_DEVICE_ID_INTEL_NTB_PS_SNB		0x3C0E +#define PCI_DEVICE_ID_INTEL_NTB_SS_SNB		0x3C0F +#define PCI_DEVICE_ID_INTEL_NTB_B2B_IVT		0x0E0D +#define PCI_DEVICE_ID_INTEL_NTB_PS_IVT		0x0E0E +#define PCI_DEVICE_ID_INTEL_NTB_SS_IVT		0x0E0F +#define PCI_DEVICE_ID_INTEL_NTB_B2B_HSX		0x2F0D +#define PCI_DEVICE_ID_INTEL_NTB_PS_HSX		0x2F0E +#define PCI_DEVICE_ID_INTEL_NTB_SS_HSX		0x2F0F +#define PCI_DEVICE_ID_INTEL_NTB_B2B_BWD		0x0C4E + +#ifndef readq +static inline u64 readq(void __iomem *addr) +{ +	return readl(addr) | (((u64) readl(addr + 4)) << 32LL); +} +#endif + +#ifndef writeq +static inline void writeq(u64 val, void __iomem *addr) +{ +	writel(val & 0xffffffff, addr); +	writel(val >> 32, addr + 4); +} +#endif + +#define NTB_BAR_MMIO		0 +#define NTB_BAR_23		2 +#define NTB_BAR_45		4 +#define NTB_BAR_MASK		((1 << NTB_BAR_MMIO) | (1 << NTB_BAR_23) |\ +				 (1 << NTB_BAR_45)) + +#define NTB_HB_TIMEOUT		msecs_to_jiffies(1000) + +#define NTB_MAX_NUM_MW		2 + +enum ntb_hw_event { +	NTB_EVENT_SW_EVENT0 = 0, +	NTB_EVENT_SW_EVENT1, +	NTB_EVENT_SW_EVENT2, +	NTB_EVENT_HW_ERROR, +	NTB_EVENT_HW_LINK_UP, +	NTB_EVENT_HW_LINK_DOWN, +}; + +struct ntb_mw { +	dma_addr_t phys_addr; +	void __iomem *vbase; +	resource_size_t bar_sz; +}; + +struct ntb_db_cb { +	int (*callback)(void *data, int db_num); +	unsigned int db_num; +	void *data; +	struct ntb_device *ndev; +	struct tasklet_struct irq_work; +}; + +struct ntb_device { +	struct pci_dev *pdev; +	struct msix_entry *msix_entries; +	void __iomem *reg_base; +	struct ntb_mw mw[NTB_MAX_NUM_MW]; +	struct { +		unsigned char max_mw; +		unsigned char max_spads; +		unsigned char max_db_bits; +		unsigned char msix_cnt; +	} limits; +	struct { +		void __iomem *ldb; +		void __iomem *ldb_mask; +		void __iomem *rdb; +		void __iomem *bar2_xlat; +		void __iomem *bar4_xlat; +		void __iomem *spad_write; +		void __iomem *spad_read; +		void __iomem *lnk_cntl; +		void __iomem *lnk_stat; +		void __iomem *spci_cmd; +	} reg_ofs; +	struct ntb_transport *ntb_transport; +	void (*event_cb)(void *handle, enum ntb_hw_event event); + +	struct ntb_db_cb *db_cb; +	unsigned char hw_type; +	unsigned char conn_type; +	unsigned char dev_type; +	unsigned char num_msix; +	unsigned char bits_per_vector; +	unsigned char max_cbs; +	unsigned char link_width; +	unsigned char link_speed; +	unsigned char link_status; + +	struct delayed_work hb_timer; +	unsigned long last_ts; + +	struct delayed_work lr_timer; + +	struct dentry *debugfs_dir; +}; + +/** + * ntb_max_cbs() - return the max callbacks + * @ndev: pointer to ntb_device instance + * + * Given the ntb pointer, return the maximum number of callbacks + * + * RETURNS: the maximum number of callbacks + */ +static inline unsigned char ntb_max_cbs(struct ntb_device *ndev) +{ +	return ndev->max_cbs; +} + +/** + * ntb_max_mw() - return the max number of memory windows + * @ndev: pointer to ntb_device instance + * + * Given the ntb pointer, return the maximum number of memory windows + * + * RETURNS: the maximum number of memory windows + */ +static inline unsigned char ntb_max_mw(struct ntb_device *ndev) +{ +	return ndev->limits.max_mw; +} + +/** + * ntb_hw_link_status() - return the hardware link status + * @ndev: pointer to ntb_device instance + * + * Returns true if the hardware is connected to the remote system + * + * RETURNS: true or false based on the hardware link state + */ +static inline bool ntb_hw_link_status(struct ntb_device *ndev) +{ +	return ndev->link_status == NTB_LINK_UP; +} + +/** + * ntb_query_pdev() - return the pci_dev pointer + * @ndev: pointer to ntb_device instance + * + * Given the ntb pointer, return the pci_dev pointer for the NTB hardware device + * + * RETURNS: a pointer to the ntb pci_dev + */ +static inline struct pci_dev *ntb_query_pdev(struct ntb_device *ndev) +{ +	return ndev->pdev; +} + +/** + * ntb_query_debugfs() - return the debugfs pointer + * @ndev: pointer to ntb_device instance + * + * Given the ntb pointer, return the debugfs directory pointer for the NTB + * hardware device + * + * RETURNS: a pointer to the debugfs directory + */ +static inline struct dentry *ntb_query_debugfs(struct ntb_device *ndev) +{ +	return ndev->debugfs_dir; +} + +struct ntb_device *ntb_register_transport(struct pci_dev *pdev, +					  void *transport); +void ntb_unregister_transport(struct ntb_device *ndev); +void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr); +int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx, +			     void *data, int (*db_cb_func)(void *data, +							   int db_num)); +void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx); +int ntb_register_event_callback(struct ntb_device *ndev, +				void (*event_cb_func)(void *handle, +						      enum ntb_hw_event event)); +void ntb_unregister_event_callback(struct ntb_device *ndev); +int ntb_get_max_spads(struct ntb_device *ndev); +int ntb_write_local_spad(struct ntb_device *ndev, unsigned int idx, u32 val); +int ntb_read_local_spad(struct ntb_device *ndev, unsigned int idx, u32 *val); +int ntb_write_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 val); +int ntb_read_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 *val); +resource_size_t ntb_get_mw_base(struct ntb_device *ndev, unsigned int mw); +void __iomem *ntb_get_mw_vbase(struct ntb_device *ndev, unsigned int mw); +u64 ntb_get_mw_size(struct ntb_device *ndev, unsigned int mw); +void ntb_ring_doorbell(struct ntb_device *ndev, unsigned int idx); +void *ntb_find_transport(struct pci_dev *pdev); + +int ntb_transport_init(struct pci_dev *pdev); +void ntb_transport_free(void *transport); diff --git a/drivers/ntb/ntb_regs.h b/drivers/ntb/ntb_regs.h new file mode 100644 index 00000000000..9774506419d --- /dev/null +++ b/drivers/ntb/ntb_regs.h @@ -0,0 +1,159 @@ +/* + * This file is provided under a dual BSD/GPLv2 license.  When using or + *   redistributing this file, you may do so under either license. + * + *   GPL LICENSE SUMMARY + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   This program is free software; you can redistribute it and/or modify + *   it under the terms of version 2 of the GNU General Public License as + *   published by the Free Software Foundation. + * + *   BSD LICENSE + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   Redistribution and use in source and binary forms, with or without + *   modification, are permitted provided that the following conditions + *   are met: + * + *     * Redistributions of source code must retain the above copyright + *       notice, this list of conditions and the following disclaimer. + *     * Redistributions in binary form must reproduce the above copy + *       notice, this list of conditions and the following disclaimer in + *       the documentation and/or other materials provided with the + *       distribution. + *     * Neither the name of Intel Corporation nor the names of its + *       contributors may be used to endorse or promote products derived + *       from this software without specific prior written permission. + * + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Intel PCIe NTB Linux driver + * + * Contact Information: + * Jon Mason <jon.mason@intel.com> + */ + +#define NTB_LINK_STATUS_ACTIVE	0x2000 +#define NTB_LINK_SPEED_MASK	0x000f +#define NTB_LINK_WIDTH_MASK	0x03f0 + +#define SNB_MSIX_CNT		4 +#define SNB_MAX_B2B_SPADS	16 +#define SNB_MAX_COMPAT_SPADS	16 +/* Reserve the uppermost bit for link interrupt */ +#define SNB_MAX_DB_BITS		15 +#define SNB_LINK_DB		15 +#define SNB_DB_BITS_PER_VEC	5 +#define SNB_MAX_MW		2 +#define SNB_ERRATA_MAX_MW	1 + +#define SNB_DB_HW_LINK		0x8000 + +#define SNB_PCICMD_OFFSET	0x0504 +#define SNB_DEVCTRL_OFFSET	0x0598 +#define SNB_SLINK_STATUS_OFFSET	0x05A2 +#define SNB_LINK_STATUS_OFFSET	0x01A2 + +#define SNB_PBAR2LMT_OFFSET	0x0000 +#define SNB_PBAR4LMT_OFFSET	0x0008 +#define SNB_PBAR2XLAT_OFFSET	0x0010 +#define SNB_PBAR4XLAT_OFFSET	0x0018 +#define SNB_SBAR2LMT_OFFSET	0x0020 +#define SNB_SBAR4LMT_OFFSET	0x0028 +#define SNB_SBAR2XLAT_OFFSET	0x0030 +#define SNB_SBAR4XLAT_OFFSET	0x0038 +#define SNB_SBAR0BASE_OFFSET	0x0040 +#define SNB_SBAR2BASE_OFFSET	0x0048 +#define SNB_SBAR4BASE_OFFSET	0x0050 +#define SNB_NTBCNTL_OFFSET	0x0058 +#define SNB_SBDF_OFFSET		0x005C +#define SNB_PDOORBELL_OFFSET	0x0060 +#define SNB_PDBMSK_OFFSET	0x0062 +#define SNB_SDOORBELL_OFFSET	0x0064 +#define SNB_SDBMSK_OFFSET	0x0066 +#define SNB_USMEMMISS		0x0070 +#define SNB_SPAD_OFFSET		0x0080 +#define SNB_SPADSEMA4_OFFSET	0x00c0 +#define SNB_WCCNTRL_OFFSET	0x00e0 +#define SNB_B2B_SPAD_OFFSET	0x0100 +#define SNB_B2B_DOORBELL_OFFSET	0x0140 +#define SNB_B2B_XLAT_OFFSETL	0x0144 +#define SNB_B2B_XLAT_OFFSETU	0x0148 + +#define SNB_MBAR01_USD_ADDR	0x000000210000000CULL +#define SNB_MBAR23_USD_ADDR	0x000000410000000CULL +#define SNB_MBAR45_USD_ADDR	0x000000810000000CULL +#define SNB_MBAR01_DSD_ADDR	0x000000200000000CULL +#define SNB_MBAR23_DSD_ADDR	0x000000400000000CULL +#define SNB_MBAR45_DSD_ADDR	0x000000800000000CULL + +#define BWD_MSIX_CNT		34 +#define BWD_MAX_SPADS		16 +#define BWD_MAX_DB_BITS		34 +#define BWD_DB_BITS_PER_VEC	1 +#define BWD_MAX_MW		2 + +#define BWD_PCICMD_OFFSET	0xb004 +#define BWD_MBAR23_OFFSET	0xb018 +#define BWD_MBAR45_OFFSET	0xb020 +#define BWD_DEVCTRL_OFFSET	0xb048 +#define BWD_LINK_STATUS_OFFSET	0xb052 +#define BWD_ERRCORSTS_OFFSET	0xb110 + +#define BWD_SBAR2XLAT_OFFSET	0x0008 +#define BWD_SBAR4XLAT_OFFSET	0x0010 +#define BWD_PDOORBELL_OFFSET	0x0020 +#define BWD_PDBMSK_OFFSET	0x0028 +#define BWD_NTBCNTL_OFFSET	0x0060 +#define BWD_EBDF_OFFSET		0x0064 +#define BWD_SPAD_OFFSET		0x0080 +#define BWD_SPADSEMA_OFFSET	0x00c0 +#define BWD_STKYSPAD_OFFSET	0x00c4 +#define BWD_PBAR2XLAT_OFFSET	0x8008 +#define BWD_PBAR4XLAT_OFFSET	0x8010 +#define BWD_B2B_DOORBELL_OFFSET	0x8020 +#define BWD_B2B_SPAD_OFFSET	0x8080 +#define BWD_B2B_SPADSEMA_OFFSET	0x80c0 +#define BWD_B2B_STKYSPAD_OFFSET	0x80c4 + +#define BWD_MODPHY_PCSREG4	0x1c004 +#define BWD_MODPHY_PCSREG6	0x1c006 + +#define BWD_IP_BASE		0xC000 +#define BWD_DESKEWSTS_OFFSET	(BWD_IP_BASE + 0x3024) +#define BWD_LTSSMERRSTS0_OFFSET (BWD_IP_BASE + 0x3180) +#define BWD_LTSSMSTATEJMP_OFFSET	(BWD_IP_BASE + 0x3040) +#define BWD_IBSTERRRCRVSTS0_OFFSET	(BWD_IP_BASE + 0x3324) + +#define BWD_DESKEWSTS_DBERR	(1 << 15) +#define BWD_LTSSMERRSTS0_UNEXPECTEDEI	(1 << 20) +#define BWD_LTSSMSTATEJMP_FORCEDETECT	(1 << 2) +#define BWD_IBIST_ERR_OFLOW	0x7FFF7FFF + +#define NTB_CNTL_CFG_LOCK		(1 << 0) +#define NTB_CNTL_LINK_DISABLE		(1 << 1) +#define NTB_CNTL_S2P_BAR23_SNOOP	(1 << 2) +#define NTB_CNTL_P2S_BAR23_SNOOP	(1 << 4) +#define NTB_CNTL_S2P_BAR45_SNOOP	(1 << 6) +#define NTB_CNTL_P2S_BAR45_SNOOP	(1 << 8) +#define BWD_CNTL_LINK_DOWN		(1 << 16) + +#define NTB_PPD_OFFSET		0x00D4 +#define SNB_PPD_CONN_TYPE	0x0003 +#define SNB_PPD_DEV_TYPE	0x0010 +#define BWD_PPD_INIT_LINK	0x0008 +#define BWD_PPD_CONN_TYPE	0x0300 +#define BWD_PPD_DEV_TYPE	0x1000 diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c new file mode 100644 index 00000000000..9dd63b82202 --- /dev/null +++ b/drivers/ntb/ntb_transport.c @@ -0,0 +1,1763 @@ +/* + * This file is provided under a dual BSD/GPLv2 license.  When using or + *   redistributing this file, you may do so under either license. + * + *   GPL LICENSE SUMMARY + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   This program is free software; you can redistribute it and/or modify + *   it under the terms of version 2 of the GNU General Public License as + *   published by the Free Software Foundation. + * + *   BSD LICENSE + * + *   Copyright(c) 2012 Intel Corporation. All rights reserved. + * + *   Redistribution and use in source and binary forms, with or without + *   modification, are permitted provided that the following conditions + *   are met: + * + *     * Redistributions of source code must retain the above copyright + *       notice, this list of conditions and the following disclaimer. + *     * Redistributions in binary form must reproduce the above copy + *       notice, this list of conditions and the following disclaimer in + *       the documentation and/or other materials provided with the + *       distribution. + *     * Neither the name of Intel Corporation nor the names of its + *       contributors may be used to endorse or promote products derived + *       from this software without specific prior written permission. + * + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Intel PCIe NTB Linux driver + * + * Contact Information: + * Jon Mason <jon.mason@intel.com> + */ +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/types.h> +#include "ntb_hw.h" + +#define NTB_TRANSPORT_VERSION	3 + +static unsigned int transport_mtu = 0x401E; +module_param(transport_mtu, uint, 0644); +MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); + +static unsigned char max_num_clients; +module_param(max_num_clients, byte, 0644); +MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); + +static unsigned int copy_bytes = 1024; +module_param(copy_bytes, uint, 0644); +MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA"); + +struct ntb_queue_entry { +	/* ntb_queue list reference */ +	struct list_head entry; +	/* pointers to data to be transfered */ +	void *cb_data; +	void *buf; +	unsigned int len; +	unsigned int flags; + +	struct ntb_transport_qp *qp; +	union { +		struct ntb_payload_header __iomem *tx_hdr; +		struct ntb_payload_header *rx_hdr; +	}; +	unsigned int index; +}; + +struct ntb_rx_info { +	unsigned int entry; +}; + +struct ntb_transport_qp { +	struct ntb_transport *transport; +	struct ntb_device *ndev; +	void *cb_data; +	struct dma_chan *dma_chan; + +	bool client_ready; +	bool qp_link; +	u8 qp_num;	/* Only 64 QP's are allowed.  0-63 */ + +	struct ntb_rx_info __iomem *rx_info; +	struct ntb_rx_info *remote_rx_info; + +	void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data, +			   void *data, int len); +	struct list_head tx_free_q; +	spinlock_t ntb_tx_free_q_lock; +	void __iomem *tx_mw; +	dma_addr_t tx_mw_phys; +	unsigned int tx_index; +	unsigned int tx_max_entry; +	unsigned int tx_max_frame; + +	void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data, +			   void *data, int len); +	struct list_head rx_pend_q; +	struct list_head rx_free_q; +	spinlock_t ntb_rx_pend_q_lock; +	spinlock_t ntb_rx_free_q_lock; +	void *rx_buff; +	unsigned int rx_index; +	unsigned int rx_max_entry; +	unsigned int rx_max_frame; +	dma_cookie_t last_cookie; + +	void (*event_handler)(void *data, int status); +	struct delayed_work link_work; +	struct work_struct link_cleanup; + +	struct dentry *debugfs_dir; +	struct dentry *debugfs_stats; + +	/* Stats */ +	u64 rx_bytes; +	u64 rx_pkts; +	u64 rx_ring_empty; +	u64 rx_err_no_buf; +	u64 rx_err_oflow; +	u64 rx_err_ver; +	u64 rx_memcpy; +	u64 rx_async; +	u64 tx_bytes; +	u64 tx_pkts; +	u64 tx_ring_full; +	u64 tx_err_no_buf; +	u64 tx_memcpy; +	u64 tx_async; +}; + +struct ntb_transport_mw { +	size_t size; +	void *virt_addr; +	dma_addr_t dma_addr; +}; + +struct ntb_transport_client_dev { +	struct list_head entry; +	struct device dev; +}; + +struct ntb_transport { +	struct list_head entry; +	struct list_head client_devs; + +	struct ntb_device *ndev; +	struct ntb_transport_mw *mw; +	struct ntb_transport_qp *qps; +	unsigned int max_qps; +	unsigned long qp_bitmap; +	bool transport_link; +	struct delayed_work link_work; +	struct work_struct link_cleanup; +}; + +enum { +	DESC_DONE_FLAG = 1 << 0, +	LINK_DOWN_FLAG = 1 << 1, +}; + +struct ntb_payload_header { +	unsigned int ver; +	unsigned int len; +	unsigned int flags; +}; + +enum { +	VERSION = 0, +	QP_LINKS, +	NUM_QPS, +	NUM_MWS, +	MW0_SZ_HIGH, +	MW0_SZ_LOW, +	MW1_SZ_HIGH, +	MW1_SZ_LOW, +	MAX_SPAD, +}; + +#define QP_TO_MW(ndev, qp)	((qp) % ntb_max_mw(ndev)) +#define NTB_QP_DEF_NUM_ENTRIES	100 +#define NTB_LINK_DOWN_TIMEOUT	10 + +static int ntb_match_bus(struct device *dev, struct device_driver *drv) +{ +	return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); +} + +static int ntb_client_probe(struct device *dev) +{ +	const struct ntb_client *drv = container_of(dev->driver, +						    struct ntb_client, driver); +	struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); +	int rc = -EINVAL; + +	get_device(dev); +	if (drv && drv->probe) +		rc = drv->probe(pdev); +	if (rc) +		put_device(dev); + +	return rc; +} + +static int ntb_client_remove(struct device *dev) +{ +	const struct ntb_client *drv = container_of(dev->driver, +						    struct ntb_client, driver); +	struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); + +	if (drv && drv->remove) +		drv->remove(pdev); + +	put_device(dev); + +	return 0; +} + +static struct bus_type ntb_bus_type = { +	.name = "ntb_bus", +	.match = ntb_match_bus, +	.probe = ntb_client_probe, +	.remove = ntb_client_remove, +}; + +static LIST_HEAD(ntb_transport_list); + +static int ntb_bus_init(struct ntb_transport *nt) +{ +	if (list_empty(&ntb_transport_list)) { +		int rc = bus_register(&ntb_bus_type); +		if (rc) +			return rc; +	} + +	list_add(&nt->entry, &ntb_transport_list); + +	return 0; +} + +static void ntb_bus_remove(struct ntb_transport *nt) +{ +	struct ntb_transport_client_dev *client_dev, *cd; + +	list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { +		dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", +			dev_name(&client_dev->dev)); +		list_del(&client_dev->entry); +		device_unregister(&client_dev->dev); +	} + +	list_del(&nt->entry); + +	if (list_empty(&ntb_transport_list)) +		bus_unregister(&ntb_bus_type); +} + +static void ntb_client_release(struct device *dev) +{ +	struct ntb_transport_client_dev *client_dev; +	client_dev = container_of(dev, struct ntb_transport_client_dev, dev); + +	kfree(client_dev); +} + +/** + * ntb_unregister_client_dev - Unregister NTB client device + * @device_name: Name of NTB client device + * + * Unregister an NTB client device with the NTB transport layer + */ +void ntb_unregister_client_dev(char *device_name) +{ +	struct ntb_transport_client_dev *client, *cd; +	struct ntb_transport *nt; + +	list_for_each_entry(nt, &ntb_transport_list, entry) +		list_for_each_entry_safe(client, cd, &nt->client_devs, entry) +			if (!strncmp(dev_name(&client->dev), device_name, +				     strlen(device_name))) { +				list_del(&client->entry); +				device_unregister(&client->dev); +			} +} +EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); + +/** + * ntb_register_client_dev - Register NTB client device + * @device_name: Name of NTB client device + * + * Register an NTB client device with the NTB transport layer + */ +int ntb_register_client_dev(char *device_name) +{ +	struct ntb_transport_client_dev *client_dev; +	struct ntb_transport *nt; +	int rc, i = 0; + +	if (list_empty(&ntb_transport_list)) +		return -ENODEV; + +	list_for_each_entry(nt, &ntb_transport_list, entry) { +		struct device *dev; + +		client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), +				     GFP_KERNEL); +		if (!client_dev) { +			rc = -ENOMEM; +			goto err; +		} + +		dev = &client_dev->dev; + +		/* setup and register client devices */ +		dev_set_name(dev, "%s%d", device_name, i); +		dev->bus = &ntb_bus_type; +		dev->release = ntb_client_release; +		dev->parent = &ntb_query_pdev(nt->ndev)->dev; + +		rc = device_register(dev); +		if (rc) { +			kfree(client_dev); +			goto err; +		} + +		list_add_tail(&client_dev->entry, &nt->client_devs); +		i++; +	} + +	return 0; + +err: +	ntb_unregister_client_dev(device_name); + +	return rc; +} +EXPORT_SYMBOL_GPL(ntb_register_client_dev); + +/** + * ntb_register_client - Register NTB client driver + * @drv: NTB client driver to be registered + * + * Register an NTB client driver with the NTB transport layer + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_register_client(struct ntb_client *drv) +{ +	drv->driver.bus = &ntb_bus_type; + +	if (list_empty(&ntb_transport_list)) +		return -ENODEV; + +	return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(ntb_register_client); + +/** + * ntb_unregister_client - Unregister NTB client driver + * @drv: NTB client driver to be unregistered + * + * Unregister an NTB client driver with the NTB transport layer + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +void ntb_unregister_client(struct ntb_client *drv) +{ +	driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(ntb_unregister_client); + +static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, +			    loff_t *offp) +{ +	struct ntb_transport_qp *qp; +	char *buf; +	ssize_t ret, out_offset, out_count; + +	out_count = 1000; + +	buf = kmalloc(out_count, GFP_KERNEL); +	if (!buf) +		return -ENOMEM; + +	qp = filp->private_data; +	out_offset = 0; +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "NTB QP stats\n"); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_bytes - \t%llu\n", qp->rx_bytes); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_pkts - \t%llu\n", qp->rx_pkts); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_memcpy - \t%llu\n", qp->rx_memcpy); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_async - \t%llu\n", qp->rx_async); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_ring_empty - %llu\n", qp->rx_ring_empty); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_err_ver - \t%llu\n", qp->rx_err_ver); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_buff - \t%p\n", qp->rx_buff); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_index - \t%u\n", qp->rx_index); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "rx_max_entry - \t%u\n", qp->rx_max_entry); + +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_bytes - \t%llu\n", qp->tx_bytes); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_pkts - \t%llu\n", qp->tx_pkts); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_memcpy - \t%llu\n", qp->tx_memcpy); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_async - \t%llu\n", qp->tx_async); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_ring_full - \t%llu\n", qp->tx_ring_full); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_mw - \t%p\n", qp->tx_mw); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_index - \t%u\n", qp->tx_index); +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "tx_max_entry - \t%u\n", qp->tx_max_entry); + +	out_offset += snprintf(buf + out_offset, out_count - out_offset, +			       "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ? +			       "Up" : "Down"); +	if (out_offset > out_count) +		out_offset = out_count; + +	ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); +	kfree(buf); +	return ret; +} + +static const struct file_operations ntb_qp_debugfs_stats = { +	.owner = THIS_MODULE, +	.open = simple_open, +	.read = debugfs_read, +}; + +static void ntb_list_add(spinlock_t *lock, struct list_head *entry, +			 struct list_head *list) +{ +	unsigned long flags; + +	spin_lock_irqsave(lock, flags); +	list_add_tail(entry, list); +	spin_unlock_irqrestore(lock, flags); +} + +static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, +					   struct list_head *list) +{ +	struct ntb_queue_entry *entry; +	unsigned long flags; + +	spin_lock_irqsave(lock, flags); +	if (list_empty(list)) { +		entry = NULL; +		goto out; +	} +	entry = list_first_entry(list, struct ntb_queue_entry, entry); +	list_del(&entry->entry); +out: +	spin_unlock_irqrestore(lock, flags); + +	return entry; +} + +static void ntb_transport_setup_qp_mw(struct ntb_transport *nt, +				      unsigned int qp_num) +{ +	struct ntb_transport_qp *qp = &nt->qps[qp_num]; +	unsigned int rx_size, num_qps_mw; +	u8 mw_num, mw_max; +	unsigned int i; + +	mw_max = ntb_max_mw(nt->ndev); +	mw_num = QP_TO_MW(nt->ndev, qp_num); + +	WARN_ON(nt->mw[mw_num].virt_addr == NULL); + +	if (nt->max_qps % mw_max && mw_num < nt->max_qps % mw_max) +		num_qps_mw = nt->max_qps / mw_max + 1; +	else +		num_qps_mw = nt->max_qps / mw_max; + +	rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw; +	qp->rx_buff = nt->mw[mw_num].virt_addr + qp_num / mw_max * rx_size; +	rx_size -= sizeof(struct ntb_rx_info); + +	qp->remote_rx_info = qp->rx_buff + rx_size; + +	/* Due to housekeeping, there must be atleast 2 buffs */ +	qp->rx_max_frame = min(transport_mtu, rx_size / 2); +	qp->rx_max_entry = rx_size / qp->rx_max_frame; +	qp->rx_index = 0; + +	qp->remote_rx_info->entry = qp->rx_max_entry - 1; + +	/* setup the hdr offsets with 0's */ +	for (i = 0; i < qp->rx_max_entry; i++) { +		void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) - +			       sizeof(struct ntb_payload_header); +		memset(offset, 0, sizeof(struct ntb_payload_header)); +	} + +	qp->rx_pkts = 0; +	qp->tx_pkts = 0; +	qp->tx_index = 0; +} + +static void ntb_free_mw(struct ntb_transport *nt, int num_mw) +{ +	struct ntb_transport_mw *mw = &nt->mw[num_mw]; +	struct pci_dev *pdev = ntb_query_pdev(nt->ndev); + +	if (!mw->virt_addr) +		return; + +	dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr); +	mw->virt_addr = NULL; +} + +static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size) +{ +	struct ntb_transport_mw *mw = &nt->mw[num_mw]; +	struct pci_dev *pdev = ntb_query_pdev(nt->ndev); + +	/* No need to re-setup */ +	if (mw->size == ALIGN(size, 4096)) +		return 0; + +	if (mw->size != 0) +		ntb_free_mw(nt, num_mw); + +	/* Alloc memory for receiving data.  Must be 4k aligned */ +	mw->size = ALIGN(size, 4096); + +	mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr, +					   GFP_KERNEL); +	if (!mw->virt_addr) { +		mw->size = 0; +		dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n", +		       (int) mw->size); +		return -ENOMEM; +	} + +	/* Notify HW the memory location of the receive buffer */ +	ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); + +	return 0; +} + +static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp) +{ +	struct ntb_transport *nt = qp->transport; +	struct pci_dev *pdev = ntb_query_pdev(nt->ndev); + +	if (qp->qp_link == NTB_LINK_DOWN) { +		cancel_delayed_work_sync(&qp->link_work); +		return; +	} + +	if (qp->event_handler) +		qp->event_handler(qp->cb_data, NTB_LINK_DOWN); + +	dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); +	qp->qp_link = NTB_LINK_DOWN; +} + +static void ntb_qp_link_cleanup_work(struct work_struct *work) +{ +	struct ntb_transport_qp *qp = container_of(work, +						   struct ntb_transport_qp, +						   link_cleanup); +	struct ntb_transport *nt = qp->transport; + +	ntb_qp_link_cleanup(qp); + +	if (nt->transport_link == NTB_LINK_UP) +		schedule_delayed_work(&qp->link_work, +				      msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); +} + +static void ntb_qp_link_down(struct ntb_transport_qp *qp) +{ +	schedule_work(&qp->link_cleanup); +} + +static void ntb_transport_link_cleanup(struct ntb_transport *nt) +{ +	int i; + +	/* Pass along the info to any clients */ +	for (i = 0; i < nt->max_qps; i++) +		if (!test_bit(i, &nt->qp_bitmap)) +			ntb_qp_link_cleanup(&nt->qps[i]); + +	if (nt->transport_link == NTB_LINK_DOWN) +		cancel_delayed_work_sync(&nt->link_work); +	else +		nt->transport_link = NTB_LINK_DOWN; + +	/* The scratchpad registers keep the values if the remote side +	 * goes down, blast them now to give them a sane value the next +	 * time they are accessed +	 */ +	for (i = 0; i < MAX_SPAD; i++) +		ntb_write_local_spad(nt->ndev, i, 0); +} + +static void ntb_transport_link_cleanup_work(struct work_struct *work) +{ +	struct ntb_transport *nt = container_of(work, struct ntb_transport, +						link_cleanup); + +	ntb_transport_link_cleanup(nt); +} + +static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) +{ +	struct ntb_transport *nt = data; + +	switch (event) { +	case NTB_EVENT_HW_LINK_UP: +		schedule_delayed_work(&nt->link_work, 0); +		break; +	case NTB_EVENT_HW_LINK_DOWN: +		schedule_work(&nt->link_cleanup); +		break; +	default: +		BUG(); +	} +} + +static void ntb_transport_link_work(struct work_struct *work) +{ +	struct ntb_transport *nt = container_of(work, struct ntb_transport, +						link_work.work); +	struct ntb_device *ndev = nt->ndev; +	struct pci_dev *pdev = ntb_query_pdev(ndev); +	u32 val; +	int rc, i; + +	/* send the local info, in the opposite order of the way we read it */ +	for (i = 0; i < ntb_max_mw(ndev); i++) { +		rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), +					   ntb_get_mw_size(ndev, i) >> 32); +		if (rc) { +			dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", +				(u32)(ntb_get_mw_size(ndev, i) >> 32), +				MW0_SZ_HIGH + (i * 2)); +			goto out; +		} + +		rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2), +					   (u32) ntb_get_mw_size(ndev, i)); +		if (rc) { +			dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", +				(u32) ntb_get_mw_size(ndev, i), +				MW0_SZ_LOW + (i * 2)); +			goto out; +		} +	} + +	rc = ntb_write_remote_spad(ndev, NUM_MWS, ntb_max_mw(ndev)); +	if (rc) { +		dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", +			ntb_max_mw(ndev), NUM_MWS); +		goto out; +	} + +	rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); +	if (rc) { +		dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", +			nt->max_qps, NUM_QPS); +		goto out; +	} + +	rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); +	if (rc) { +		dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", +			NTB_TRANSPORT_VERSION, VERSION); +		goto out; +	} + +	/* Query the remote side for its info */ +	rc = ntb_read_remote_spad(ndev, VERSION, &val); +	if (rc) { +		dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); +		goto out; +	} + +	if (val != NTB_TRANSPORT_VERSION) +		goto out; +	dev_dbg(&pdev->dev, "Remote version = %d\n", val); + +	rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); +	if (rc) { +		dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); +		goto out; +	} + +	if (val != nt->max_qps) +		goto out; +	dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); + +	rc = ntb_read_remote_spad(ndev, NUM_MWS, &val); +	if (rc) { +		dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS); +		goto out; +	} + +	if (val != ntb_max_mw(ndev)) +		goto out; +	dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); + +	for (i = 0; i < ntb_max_mw(ndev); i++) { +		u64 val64; + +		rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val); +		if (rc) { +			dev_err(&pdev->dev, "Error reading remote spad %d\n", +				MW0_SZ_HIGH + (i * 2)); +			goto out1; +		} + +		val64 = (u64) val << 32; + +		rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val); +		if (rc) { +			dev_err(&pdev->dev, "Error reading remote spad %d\n", +				MW0_SZ_LOW + (i * 2)); +			goto out1; +		} + +		val64 |= val; + +		dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64); + +		rc = ntb_set_mw(nt, i, val64); +		if (rc) +			goto out1; +	} + +	nt->transport_link = NTB_LINK_UP; + +	for (i = 0; i < nt->max_qps; i++) { +		struct ntb_transport_qp *qp = &nt->qps[i]; + +		ntb_transport_setup_qp_mw(nt, i); + +		if (qp->client_ready == NTB_LINK_UP) +			schedule_delayed_work(&qp->link_work, 0); +	} + +	return; + +out1: +	for (i = 0; i < ntb_max_mw(ndev); i++) +		ntb_free_mw(nt, i); +out: +	if (ntb_hw_link_status(ndev)) +		schedule_delayed_work(&nt->link_work, +				      msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); +} + +static void ntb_qp_link_work(struct work_struct *work) +{ +	struct ntb_transport_qp *qp = container_of(work, +						   struct ntb_transport_qp, +						   link_work.work); +	struct pci_dev *pdev = ntb_query_pdev(qp->ndev); +	struct ntb_transport *nt = qp->transport; +	int rc, val; + +	WARN_ON(nt->transport_link != NTB_LINK_UP); + +	rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); +	if (rc) { +		dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); +		return; +	} + +	rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); +	if (rc) +		dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", +			val | 1 << qp->qp_num, QP_LINKS); + +	/* query remote spad for qp ready bits */ +	rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); +	if (rc) +		dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); + +	dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); + +	/* See if the remote side is up */ +	if (1 << qp->qp_num & val) { +		qp->qp_link = NTB_LINK_UP; + +		dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); +		if (qp->event_handler) +			qp->event_handler(qp->cb_data, NTB_LINK_UP); +	} else if (nt->transport_link == NTB_LINK_UP) +		schedule_delayed_work(&qp->link_work, +				      msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); +} + +static int ntb_transport_init_queue(struct ntb_transport *nt, +				    unsigned int qp_num) +{ +	struct ntb_transport_qp *qp; +	unsigned int num_qps_mw, tx_size; +	u8 mw_num, mw_max; +	u64 qp_offset; + +	mw_max = ntb_max_mw(nt->ndev); +	mw_num = QP_TO_MW(nt->ndev, qp_num); + +	qp = &nt->qps[qp_num]; +	qp->qp_num = qp_num; +	qp->transport = nt; +	qp->ndev = nt->ndev; +	qp->qp_link = NTB_LINK_DOWN; +	qp->client_ready = NTB_LINK_DOWN; +	qp->event_handler = NULL; + +	if (nt->max_qps % mw_max && mw_num < nt->max_qps % mw_max) +		num_qps_mw = nt->max_qps / mw_max + 1; +	else +		num_qps_mw = nt->max_qps / mw_max; + +	tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; +	qp_offset = qp_num / mw_max * tx_size; +	qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset; +	if (!qp->tx_mw) +		return -EINVAL; + +	qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset; +	if (!qp->tx_mw_phys) +		return -EINVAL; + +	tx_size -= sizeof(struct ntb_rx_info); +	qp->rx_info = qp->tx_mw + tx_size; + +	/* Due to housekeeping, there must be atleast 2 buffs */ +	qp->tx_max_frame = min(transport_mtu, tx_size / 2); +	qp->tx_max_entry = tx_size / qp->tx_max_frame; + +	if (ntb_query_debugfs(nt->ndev)) { +		char debugfs_name[4]; + +		snprintf(debugfs_name, 4, "qp%d", qp_num); +		qp->debugfs_dir = debugfs_create_dir(debugfs_name, +						 ntb_query_debugfs(nt->ndev)); + +		qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, +							qp->debugfs_dir, qp, +							&ntb_qp_debugfs_stats); +	} + +	INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); +	INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work); + +	spin_lock_init(&qp->ntb_rx_pend_q_lock); +	spin_lock_init(&qp->ntb_rx_free_q_lock); +	spin_lock_init(&qp->ntb_tx_free_q_lock); + +	INIT_LIST_HEAD(&qp->rx_pend_q); +	INIT_LIST_HEAD(&qp->rx_free_q); +	INIT_LIST_HEAD(&qp->tx_free_q); + +	return 0; +} + +int ntb_transport_init(struct pci_dev *pdev) +{ +	struct ntb_transport *nt; +	int rc, i; + +	nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); +	if (!nt) +		return -ENOMEM; + +	nt->ndev = ntb_register_transport(pdev, nt); +	if (!nt->ndev) { +		rc = -EIO; +		goto err; +	} + +	nt->mw = kcalloc(ntb_max_mw(nt->ndev), sizeof(struct ntb_transport_mw), +			 GFP_KERNEL); +	if (!nt->mw) { +		rc = -ENOMEM; +		goto err1; +	} + +	if (max_num_clients) +		nt->max_qps = min(ntb_max_cbs(nt->ndev), max_num_clients); +	else +		nt->max_qps = min(ntb_max_cbs(nt->ndev), ntb_max_mw(nt->ndev)); + +	nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), +			  GFP_KERNEL); +	if (!nt->qps) { +		rc = -ENOMEM; +		goto err2; +	} + +	nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; + +	for (i = 0; i < nt->max_qps; i++) { +		rc = ntb_transport_init_queue(nt, i); +		if (rc) +			goto err3; +	} + +	INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); +	INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work); + +	rc = ntb_register_event_callback(nt->ndev, +					 ntb_transport_event_callback); +	if (rc) +		goto err3; + +	INIT_LIST_HEAD(&nt->client_devs); +	rc = ntb_bus_init(nt); +	if (rc) +		goto err4; + +	if (ntb_hw_link_status(nt->ndev)) +		schedule_delayed_work(&nt->link_work, 0); + +	return 0; + +err4: +	ntb_unregister_event_callback(nt->ndev); +err3: +	kfree(nt->qps); +err2: +	kfree(nt->mw); +err1: +	ntb_unregister_transport(nt->ndev); +err: +	kfree(nt); +	return rc; +} + +void ntb_transport_free(void *transport) +{ +	struct ntb_transport *nt = transport; +	struct ntb_device *ndev = nt->ndev; +	int i; + +	ntb_transport_link_cleanup(nt); + +	/* verify that all the qp's are freed */ +	for (i = 0; i < nt->max_qps; i++) { +		if (!test_bit(i, &nt->qp_bitmap)) +			ntb_transport_free_queue(&nt->qps[i]); +		debugfs_remove_recursive(nt->qps[i].debugfs_dir); +	} + +	ntb_bus_remove(nt); + +	cancel_delayed_work_sync(&nt->link_work); + +	ntb_unregister_event_callback(ndev); + +	for (i = 0; i < ntb_max_mw(ndev); i++) +		ntb_free_mw(nt, i); + +	kfree(nt->qps); +	kfree(nt->mw); +	ntb_unregister_transport(ndev); +	kfree(nt); +} + +static void ntb_rx_copy_callback(void *data) +{ +	struct ntb_queue_entry *entry = data; +	struct ntb_transport_qp *qp = entry->qp; +	void *cb_data = entry->cb_data; +	unsigned int len = entry->len; +	struct ntb_payload_header *hdr = entry->rx_hdr; + +	/* Ensure that the data is fully copied out before clearing the flag */ +	wmb(); +	hdr->flags = 0; + +	iowrite32(entry->index, &qp->rx_info->entry); + +	ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); + +	if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) +		qp->rx_handler(qp, qp->cb_data, cb_data, len); +} + +static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) +{ +	void *buf = entry->buf; +	size_t len = entry->len; + +	memcpy(buf, offset, len); + +	ntb_rx_copy_callback(entry); +} + +static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset, +			 size_t len) +{ +	struct dma_async_tx_descriptor *txd; +	struct ntb_transport_qp *qp = entry->qp; +	struct dma_chan *chan = qp->dma_chan; +	struct dma_device *device; +	size_t pay_off, buff_off; +	struct dmaengine_unmap_data *unmap; +	dma_cookie_t cookie; +	void *buf = entry->buf; + +	entry->len = len; + +	if (!chan) +		goto err; + +	if (len < copy_bytes) +		goto err_wait; + +	device = chan->device; +	pay_off = (size_t) offset & ~PAGE_MASK; +	buff_off = (size_t) buf & ~PAGE_MASK; + +	if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) +		goto err_wait; + +	unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT); +	if (!unmap) +		goto err_wait; + +	unmap->len = len; +	unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), +				      pay_off, len, DMA_TO_DEVICE); +	if (dma_mapping_error(device->dev, unmap->addr[0])) +		goto err_get_unmap; + +	unmap->to_cnt = 1; + +	unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf), +				      buff_off, len, DMA_FROM_DEVICE); +	if (dma_mapping_error(device->dev, unmap->addr[1])) +		goto err_get_unmap; + +	unmap->from_cnt = 1; + +	txd = device->device_prep_dma_memcpy(chan, unmap->addr[1], +					     unmap->addr[0], len, +					     DMA_PREP_INTERRUPT); +	if (!txd) +		goto err_get_unmap; + +	txd->callback = ntb_rx_copy_callback; +	txd->callback_param = entry; +	dma_set_unmap(txd, unmap); + +	cookie = dmaengine_submit(txd); +	if (dma_submit_error(cookie)) +		goto err_set_unmap; + +	dmaengine_unmap_put(unmap); + +	qp->last_cookie = cookie; + +	qp->rx_async++; + +	return; + +err_set_unmap: +	dmaengine_unmap_put(unmap); +err_get_unmap: +	dmaengine_unmap_put(unmap); +err_wait: +	/* If the callbacks come out of order, the writing of the index to the +	 * last completed will be out of order.  This may result in the +	 * receive stalling forever. +	 */ +	dma_sync_wait(chan, qp->last_cookie); +err: +	ntb_memcpy_rx(entry, offset); +	qp->rx_memcpy++; +} + +static int ntb_process_rxc(struct ntb_transport_qp *qp) +{ +	struct ntb_payload_header *hdr; +	struct ntb_queue_entry *entry; +	void *offset; + +	offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; +	hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); + +	entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); +	if (!entry) { +		dev_dbg(&ntb_query_pdev(qp->ndev)->dev, +			"no buffer - HDR ver %u, len %d, flags %x\n", +			hdr->ver, hdr->len, hdr->flags); +		qp->rx_err_no_buf++; +		return -ENOMEM; +	} + +	if (!(hdr->flags & DESC_DONE_FLAG)) { +		ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, +			     &qp->rx_pend_q); +		qp->rx_ring_empty++; +		return -EAGAIN; +	} + +	if (hdr->ver != (u32) qp->rx_pkts) { +		dev_dbg(&ntb_query_pdev(qp->ndev)->dev, +			"qp %d: version mismatch, expected %llu - got %u\n", +			qp->qp_num, qp->rx_pkts, hdr->ver); +		ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, +			     &qp->rx_pend_q); +		qp->rx_err_ver++; +		return -EIO; +	} + +	if (hdr->flags & LINK_DOWN_FLAG) { +		ntb_qp_link_down(qp); + +		goto err; +	} + +	dev_dbg(&ntb_query_pdev(qp->ndev)->dev, +		"rx offset %u, ver %u - %d payload received, buf size %d\n", +		qp->rx_index, hdr->ver, hdr->len, entry->len); + +	qp->rx_bytes += hdr->len; +	qp->rx_pkts++; + +	if (hdr->len > entry->len) { +		qp->rx_err_oflow++; +		dev_dbg(&ntb_query_pdev(qp->ndev)->dev, +			"RX overflow! Wanted %d got %d\n", +			hdr->len, entry->len); + +		goto err; +	} + +	entry->index = qp->rx_index; +	entry->rx_hdr = hdr; + +	ntb_async_rx(entry, offset, hdr->len); + +out: +	qp->rx_index++; +	qp->rx_index %= qp->rx_max_entry; + +	return 0; + +err: +	ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); +	/* Ensure that the data is fully copied out before clearing the flag */ +	wmb(); +	hdr->flags = 0; +	iowrite32(qp->rx_index, &qp->rx_info->entry); + +	goto out; +} + +static int ntb_transport_rxc_db(void *data, int db_num) +{ +	struct ntb_transport_qp *qp = data; +	int rc, i; + +	dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", +		__func__, db_num); + +	/* Limit the number of packets processed in a single interrupt to +	 * provide fairness to others +	 */ +	for (i = 0; i < qp->rx_max_entry; i++) { +		rc = ntb_process_rxc(qp); +		if (rc) +			break; +	} + +	if (qp->dma_chan) +		dma_async_issue_pending(qp->dma_chan); + +	return i; +} + +static void ntb_tx_copy_callback(void *data) +{ +	struct ntb_queue_entry *entry = data; +	struct ntb_transport_qp *qp = entry->qp; +	struct ntb_payload_header __iomem *hdr = entry->tx_hdr; + +	/* Ensure that the data is fully copied out before setting the flags */ +	wmb(); +	iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); + +	ntb_ring_doorbell(qp->ndev, qp->qp_num); + +	/* The entry length can only be zero if the packet is intended to be a +	 * "link down" or similar.  Since no payload is being sent in these +	 * cases, there is nothing to add to the completion queue. +	 */ +	if (entry->len > 0) { +		qp->tx_bytes += entry->len; + +		if (qp->tx_handler) +			qp->tx_handler(qp, qp->cb_data, entry->cb_data, +				       entry->len); +	} + +	ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); +} + +static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) +{ +	memcpy_toio(offset, entry->buf, entry->len); + +	ntb_tx_copy_callback(entry); +} + +static void ntb_async_tx(struct ntb_transport_qp *qp, +			 struct ntb_queue_entry *entry) +{ +	struct ntb_payload_header __iomem *hdr; +	struct dma_async_tx_descriptor *txd; +	struct dma_chan *chan = qp->dma_chan; +	struct dma_device *device; +	size_t dest_off, buff_off; +	struct dmaengine_unmap_data *unmap; +	dma_addr_t dest; +	dma_cookie_t cookie; +	void __iomem *offset; +	size_t len = entry->len; +	void *buf = entry->buf; + +	offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; +	hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); +	entry->tx_hdr = hdr; + +	iowrite32(entry->len, &hdr->len); +	iowrite32((u32) qp->tx_pkts, &hdr->ver); + +	if (!chan) +		goto err; + +	if (len < copy_bytes) +		goto err; + +	device = chan->device; +	dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; +	buff_off = (size_t) buf & ~PAGE_MASK; +	dest_off = (size_t) dest & ~PAGE_MASK; + +	if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) +		goto err; + +	unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT); +	if (!unmap) +		goto err; + +	unmap->len = len; +	unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf), +				      buff_off, len, DMA_TO_DEVICE); +	if (dma_mapping_error(device->dev, unmap->addr[0])) +		goto err_get_unmap; + +	unmap->to_cnt = 1; + +	txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len, +					     DMA_PREP_INTERRUPT); +	if (!txd) +		goto err_get_unmap; + +	txd->callback = ntb_tx_copy_callback; +	txd->callback_param = entry; +	dma_set_unmap(txd, unmap); + +	cookie = dmaengine_submit(txd); +	if (dma_submit_error(cookie)) +		goto err_set_unmap; + +	dmaengine_unmap_put(unmap); + +	dma_async_issue_pending(chan); +	qp->tx_async++; + +	return; +err_set_unmap: +	dmaengine_unmap_put(unmap); +err_get_unmap: +	dmaengine_unmap_put(unmap); +err: +	ntb_memcpy_tx(entry, offset); +	qp->tx_memcpy++; +} + +static int ntb_process_tx(struct ntb_transport_qp *qp, +			  struct ntb_queue_entry *entry) +{ +	dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n", +		qp->tx_pkts, qp->tx_index, entry->len, entry->flags, +		entry->buf); +	if (qp->tx_index == qp->remote_rx_info->entry) { +		qp->tx_ring_full++; +		return -EAGAIN; +	} + +	if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { +		if (qp->tx_handler) +			qp->tx_handler(qp->cb_data, qp, NULL, -EIO); + +		ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, +			     &qp->tx_free_q); +		return 0; +	} + +	ntb_async_tx(qp, entry); + +	qp->tx_index++; +	qp->tx_index %= qp->tx_max_entry; + +	qp->tx_pkts++; + +	return 0; +} + +static void ntb_send_link_down(struct ntb_transport_qp *qp) +{ +	struct pci_dev *pdev = ntb_query_pdev(qp->ndev); +	struct ntb_queue_entry *entry; +	int i, rc; + +	if (qp->qp_link == NTB_LINK_DOWN) +		return; + +	qp->qp_link = NTB_LINK_DOWN; +	dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); + +	for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { +		entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); +		if (entry) +			break; +		msleep(100); +	} + +	if (!entry) +		return; + +	entry->cb_data = NULL; +	entry->buf = NULL; +	entry->len = 0; +	entry->flags = LINK_DOWN_FLAG; + +	rc = ntb_process_tx(qp, entry); +	if (rc) +		dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", +			qp->qp_num); +} + +/** + * ntb_transport_create_queue - Create a new NTB transport layer queue + * @rx_handler: receive callback function + * @tx_handler: transmit callback function + * @event_handler: event callback function + * + * Create a new NTB transport layer queue and provide the queue with a callback + * routine for both transmit and receive.  The receive callback routine will be + * used to pass up data when the transport has received it on the queue.   The + * transmit callback routine will be called when the transport has completed the + * transmission of the data on the queue and the data is ready to be freed. + * + * RETURNS: pointer to newly created ntb_queue, NULL on error. + */ +struct ntb_transport_qp * +ntb_transport_create_queue(void *data, struct pci_dev *pdev, +			   const struct ntb_queue_handlers *handlers) +{ +	struct ntb_queue_entry *entry; +	struct ntb_transport_qp *qp; +	struct ntb_transport *nt; +	unsigned int free_queue; +	int rc, i; + +	nt = ntb_find_transport(pdev); +	if (!nt) +		goto err; + +	free_queue = ffs(nt->qp_bitmap); +	if (!free_queue) +		goto err; + +	/* decrement free_queue to make it zero based */ +	free_queue--; + +	clear_bit(free_queue, &nt->qp_bitmap); + +	qp = &nt->qps[free_queue]; +	qp->cb_data = data; +	qp->rx_handler = handlers->rx_handler; +	qp->tx_handler = handlers->tx_handler; +	qp->event_handler = handlers->event_handler; + +	dmaengine_get(); +	qp->dma_chan = dma_find_channel(DMA_MEMCPY); +	if (!qp->dma_chan) { +		dmaengine_put(); +		dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n"); +	} + +	for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { +		entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); +		if (!entry) +			goto err1; + +		entry->qp = qp; +		ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, +			     &qp->rx_free_q); +	} + +	for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { +		entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); +		if (!entry) +			goto err2; + +		entry->qp = qp; +		ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, +			     &qp->tx_free_q); +	} + +	rc = ntb_register_db_callback(qp->ndev, free_queue, qp, +				      ntb_transport_rxc_db); +	if (rc) +		goto err2; + +	dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); + +	return qp; + +err2: +	while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) +		kfree(entry); +err1: +	while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) +		kfree(entry); +	if (qp->dma_chan) +		dmaengine_put(); +	set_bit(free_queue, &nt->qp_bitmap); +err: +	return NULL; +} +EXPORT_SYMBOL_GPL(ntb_transport_create_queue); + +/** + * ntb_transport_free_queue - Frees NTB transport queue + * @qp: NTB queue to be freed + * + * Frees NTB transport queue + */ +void ntb_transport_free_queue(struct ntb_transport_qp *qp) +{ +	struct pci_dev *pdev; +	struct ntb_queue_entry *entry; + +	if (!qp) +		return; + +	pdev = ntb_query_pdev(qp->ndev); + +	if (qp->dma_chan) { +		struct dma_chan *chan = qp->dma_chan; +		/* Putting the dma_chan to NULL will force any new traffic to be +		 * processed by the CPU instead of the DAM engine +		 */ +		qp->dma_chan = NULL; + +		/* Try to be nice and wait for any queued DMA engine +		 * transactions to process before smashing it with a rock +		 */ +		dma_sync_wait(chan, qp->last_cookie); +		dmaengine_terminate_all(chan); +		dmaengine_put(); +	} + +	ntb_unregister_db_callback(qp->ndev, qp->qp_num); + +	cancel_delayed_work_sync(&qp->link_work); + +	while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) +		kfree(entry); + +	while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { +		dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); +		kfree(entry); +	} + +	while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) +		kfree(entry); + +	set_bit(qp->qp_num, &qp->transport->qp_bitmap); + +	dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); +} +EXPORT_SYMBOL_GPL(ntb_transport_free_queue); + +/** + * ntb_transport_rx_remove - Dequeues enqueued rx packet + * @qp: NTB queue to be freed + * @len: pointer to variable to write enqueued buffers length + * + * Dequeues unused buffers from receive queue.  Should only be used during + * shutdown of qp. + * + * RETURNS: NULL error value on error, or void* for success. + */ +void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) +{ +	struct ntb_queue_entry *entry; +	void *buf; + +	if (!qp || qp->client_ready == NTB_LINK_UP) +		return NULL; + +	entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); +	if (!entry) +		return NULL; + +	buf = entry->cb_data; +	*len = entry->len; + +	ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); + +	return buf; +} +EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); + +/** + * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry + * @qp: NTB transport layer queue the entry is to be enqueued on + * @cb: per buffer pointer for callback function to use + * @data: pointer to data buffer that incoming packets will be copied into + * @len: length of the data buffer + * + * Enqueue a new receive buffer onto the transport queue into which a NTB + * payload can be received into. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, +			     unsigned int len) +{ +	struct ntb_queue_entry *entry; + +	if (!qp) +		return -EINVAL; + +	entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); +	if (!entry) +		return -ENOMEM; + +	entry->cb_data = cb; +	entry->buf = data; +	entry->len = len; + +	ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); + +	return 0; +} +EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); + +/** + * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry + * @qp: NTB transport layer queue the entry is to be enqueued on + * @cb: per buffer pointer for callback function to use + * @data: pointer to data buffer that will be sent + * @len: length of the data buffer + * + * Enqueue a new transmit buffer onto the transport queue from which a NTB + * payload will be transmitted.  This assumes that a lock is being held to + * serialize access to the qp. + * + * RETURNS: An appropriate -ERRNO error value on error, or zero for success. + */ +int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, +			     unsigned int len) +{ +	struct ntb_queue_entry *entry; +	int rc; + +	if (!qp || qp->qp_link != NTB_LINK_UP || !len) +		return -EINVAL; + +	entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); +	if (!entry) { +		qp->tx_err_no_buf++; +		return -ENOMEM; +	} + +	entry->cb_data = cb; +	entry->buf = data; +	entry->len = len; +	entry->flags = 0; + +	rc = ntb_process_tx(qp, entry); +	if (rc) +		ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, +			     &qp->tx_free_q); + +	return rc; +} +EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); + +/** + * ntb_transport_link_up - Notify NTB transport of client readiness to use queue + * @qp: NTB transport layer queue to be enabled + * + * Notify NTB transport layer of client readiness to use queue + */ +void ntb_transport_link_up(struct ntb_transport_qp *qp) +{ +	if (!qp) +		return; + +	qp->client_ready = NTB_LINK_UP; + +	if (qp->transport->transport_link == NTB_LINK_UP) +		schedule_delayed_work(&qp->link_work, 0); +} +EXPORT_SYMBOL_GPL(ntb_transport_link_up); + +/** + * ntb_transport_link_down - Notify NTB transport to no longer enqueue data + * @qp: NTB transport layer queue to be disabled + * + * Notify NTB transport layer of client's desire to no longer receive data on + * transport queue specified.  It is the client's responsibility to ensure all + * entries on queue are purged or otherwise handled appropriately. + */ +void ntb_transport_link_down(struct ntb_transport_qp *qp) +{ +	struct pci_dev *pdev; +	int rc, val; + +	if (!qp) +		return; + +	pdev = ntb_query_pdev(qp->ndev); +	qp->client_ready = NTB_LINK_DOWN; + +	rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); +	if (rc) { +		dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); +		return; +	} + +	rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, +				   val & ~(1 << qp->qp_num)); +	if (rc) +		dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", +			val & ~(1 << qp->qp_num), QP_LINKS); + +	if (qp->qp_link == NTB_LINK_UP) +		ntb_send_link_down(qp); +	else +		cancel_delayed_work_sync(&qp->link_work); +} +EXPORT_SYMBOL_GPL(ntb_transport_link_down); + +/** + * ntb_transport_link_query - Query transport link state + * @qp: NTB transport layer queue to be queried + * + * Query connectivity to the remote system of the NTB transport queue + * + * RETURNS: true for link up or false for link down + */ +bool ntb_transport_link_query(struct ntb_transport_qp *qp) +{ +	if (!qp) +		return false; + +	return qp->qp_link == NTB_LINK_UP; +} +EXPORT_SYMBOL_GPL(ntb_transport_link_query); + +/** + * ntb_transport_qp_num - Query the qp number + * @qp: NTB transport layer queue to be queried + * + * Query qp number of the NTB transport queue + * + * RETURNS: a zero based number specifying the qp number + */ +unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) +{ +	if (!qp) +		return 0; + +	return qp->qp_num; +} +EXPORT_SYMBOL_GPL(ntb_transport_qp_num); + +/** + * ntb_transport_max_size - Query the max payload size of a qp + * @qp: NTB transport layer queue to be queried + * + * Query the maximum payload size permissible on the given qp + * + * RETURNS: the max payload size of a qp + */ +unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) +{ +	unsigned int max; + +	if (!qp) +		return 0; + +	if (!qp->dma_chan) +		return qp->tx_max_frame - sizeof(struct ntb_payload_header); + +	/* If DMA engine usage is possible, try to find the max size for that */ +	max = qp->tx_max_frame - sizeof(struct ntb_payload_header); +	max -= max % (1 << qp->dma_chan->device->copy_align); + +	return max; +} +EXPORT_SYMBOL_GPL(ntb_transport_max_size);  | 
