path: root/drivers/ntb/ntb_hw.c

/*
 * 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/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.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		"0.25"

MODULE_DESCRIPTION(NTB_NAME);
MODULE_VERSION(NTB_VER);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Intel Corporation");

enum {
	NTB_CONN_CLASSIC = 0,
	NTB_CONN_B2B,
	NTB_CONN_RP,
};

enum {
	NTB_DEV_USD = 0,
	NTB_DEV_DSD,
};

enum {
	SNB_HW = 0,
	BWD_HW,
};

/* Translate memory window 0,1 to BAR 2,4 */
#define MW_TO_BAR(mw)	(mw * 2 + 2)

static DEFINE_PCI_DEVICE_TABLE(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_CLASSIC_JSF)},
	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_RP_JSF)},
	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_RP_SNB)},
	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SNB)},
	{PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_CLASSIC_SNB)},
	{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;
}

/**
 * ntb_register_db_callback() - register a callback for doorbell interrupt
 * @ndev: pointer to ntb_device instance
 * @idx: doorbell index to register callback, zero based
 * @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, void (*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;

	/* unmask interrupt */
	mask = readw(ndev->reg_ofs.pdb_mask);
	clear_bit(idx * ndev->bits_per_vector, &mask);
	writew(mask, ndev->reg_ofs.pdb_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)
{