diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/eeh.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/eeh.c | 1290 |
1 files changed, 0 insertions, 1290 deletions
diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c deleted file mode 100644 index 34b7dc12e73..00000000000 --- a/arch/powerpc/platforms/pseries/eeh.c +++ /dev/null @@ -1,1290 +0,0 @@ -/* - * eeh.c - * Copyright IBM Corporation 2001, 2005, 2006 - * Copyright Dave Engebretsen & Todd Inglett 2001 - * Copyright Linas Vepstas 2005, 2006 - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - * Please address comments and feedback to Linas Vepstas <linas@austin.ibm.com> - */ - -#undef DEBUG - -#include <linux/delay.h> -#include <linux/init.h> -#include <linux/list.h> -#include <linux/pci.h> -#include <linux/proc_fs.h> -#include <linux/rbtree.h> -#include <linux/seq_file.h> -#include <linux/spinlock.h> -#include <linux/of.h> - -#include <asm/atomic.h> -#include <asm/eeh.h> -#include <asm/eeh_event.h> -#include <asm/io.h> -#include <asm/machdep.h> -#include <asm/ppc-pci.h> -#include <asm/rtas.h> - - -/** Overview: - * EEH, or "Extended Error Handling" is a PCI bridge technology for - * dealing with PCI bus errors that can't be dealt with within the - * usual PCI framework, except by check-stopping the CPU. Systems - * that are designed for high-availability/reliability cannot afford - * to crash due to a "mere" PCI error, thus the need for EEH. - * An EEH-capable bridge operates by converting a detected error - * into a "slot freeze", taking the PCI adapter off-line, making - * the slot behave, from the OS'es point of view, as if the slot - * were "empty": all reads return 0xff's and all writes are silently - * ignored. EEH slot isolation events can be triggered by parity - * errors on the address or data busses (e.g. during posted writes), - * which in turn might be caused by low voltage on the bus, dust, - * vibration, humidity, radioactivity or plain-old failed hardware. - * - * Note, however, that one of the leading causes of EEH slot - * freeze events are buggy device drivers, buggy device microcode, - * or buggy device hardware. This is because any attempt by the - * device to bus-master data to a memory address that is not - * assigned to the device will trigger a slot freeze. (The idea - * is to prevent devices-gone-wild from corrupting system memory). - * Buggy hardware/drivers will have a miserable time co-existing - * with EEH. - * - * Ideally, a PCI device driver, when suspecting that an isolation - * event has occured (e.g. by reading 0xff's), will then ask EEH - * whether this is the case, and then take appropriate steps to - * reset the PCI slot, the PCI device, and then resume operations. - * However, until that day, the checking is done here, with the - * eeh_check_failure() routine embedded in the MMIO macros. If - * the slot is found to be isolated, an "EEH Event" is synthesized - * and sent out for processing. - */ - -/* If a device driver keeps reading an MMIO register in an interrupt - * handler after a slot isolation event, it might be broken. - * This sets the threshold for how many read attempts we allow - * before printing an error message. - */ -#define EEH_MAX_FAILS 2100000 - -/* Time to wait for a PCI slot to report status, in milliseconds */ -#define PCI_BUS_RESET_WAIT_MSEC (60*1000) - -/* RTAS tokens */ -static int ibm_set_eeh_option; -static int ibm_set_slot_reset; -static int ibm_read_slot_reset_state; -static int ibm_read_slot_reset_state2; -static int ibm_slot_error_detail; -static int ibm_get_config_addr_info; -static int ibm_get_config_addr_info2; -static int ibm_configure_bridge; - -int eeh_subsystem_enabled; -EXPORT_SYMBOL(eeh_subsystem_enabled); - -/* Lock to avoid races due to multiple reports of an error */ -static DEFINE_RAW_SPINLOCK(confirm_error_lock); - -/* Buffer for reporting slot-error-detail rtas calls. Its here - * in BSS, and not dynamically alloced, so that it ends up in - * RMO where RTAS can access it. - */ -static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX]; -static DEFINE_SPINLOCK(slot_errbuf_lock); -static int eeh_error_buf_size; - -/* Buffer for reporting pci register dumps. Its here in BSS, and - * not dynamically alloced, so that it ends up in RMO where RTAS - * can access it. - */ -#define EEH_PCI_REGS_LOG_LEN 4096 -static unsigned char pci_regs_buf[EEH_PCI_REGS_LOG_LEN]; - -/* System monitoring statistics */ -static unsigned long no_device; -static unsigned long no_dn; -static unsigned long no_cfg_addr; -static unsigned long ignored_check; -static unsigned long total_mmio_ffs; -static unsigned long false_positives; -static unsigned long slot_resets; - -#define IS_BRIDGE(class_code) (((class_code)<<16) == PCI_BASE_CLASS_BRIDGE) - -/* --------------------------------------------------------------- */ -/* Below lies the EEH event infrastructure */ - -static void rtas_slot_error_detail(struct pci_dn *pdn, int severity, - char *driver_log, size_t loglen) -{ - int config_addr; - unsigned long flags; - int rc; - - /* Log the error with the rtas logger */ - spin_lock_irqsave(&slot_errbuf_lock, flags); - memset(slot_errbuf, 0, eeh_error_buf_size); - - /* Use PE configuration address, if present */ - config_addr = pdn->eeh_config_addr; - if (pdn->eeh_pe_config_addr) - config_addr = pdn->eeh_pe_config_addr; - - rc = rtas_call(ibm_slot_error_detail, - 8, 1, NULL, config_addr, - BUID_HI(pdn->phb->buid), - BUID_LO(pdn->phb->buid), - virt_to_phys(driver_log), loglen, - virt_to_phys(slot_errbuf), - eeh_error_buf_size, - severity); - - if (rc == 0) - log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0); - spin_unlock_irqrestore(&slot_errbuf_lock, flags); -} - -/** - * gather_pci_data - copy assorted PCI config space registers to buff - * @pdn: device to report data for - * @buf: point to buffer in which to log - * @len: amount of room in buffer - * - * This routine captures assorted PCI configuration space data, - * and puts them into a buffer for RTAS error logging. - */ -static size_t gather_pci_data(struct pci_dn *pdn, char * buf, size_t len) -{ - struct pci_dev *dev = pdn->pcidev; - u32 cfg; - int cap, i; - int n = 0; - - n += scnprintf(buf+n, len-n, "%s\n", pdn->node->full_name); - printk(KERN_WARNING "EEH: of node=%s\n", pdn->node->full_name); - - rtas_read_config(pdn, PCI_VENDOR_ID, 4, &cfg); - n += scnprintf(buf+n, len-n, "dev/vend:%08x\n", cfg); - printk(KERN_WARNING "EEH: PCI device/vendor: %08x\n", cfg); - - rtas_read_config(pdn, PCI_COMMAND, 4, &cfg); - n += scnprintf(buf+n, len-n, "cmd/stat:%x\n", cfg); - printk(KERN_WARNING "EEH: PCI cmd/status register: %08x\n", cfg); - - if (!dev) { - printk(KERN_WARNING "EEH: no PCI device for this of node\n"); - return n; - } - - /* Gather bridge-specific registers */ - if (dev->class >> 16 == PCI_BASE_CLASS_BRIDGE) { - rtas_read_config(pdn, PCI_SEC_STATUS, 2, &cfg); - n += scnprintf(buf+n, len-n, "sec stat:%x\n", cfg); - printk(KERN_WARNING "EEH: Bridge secondary status: %04x\n", cfg); - - rtas_read_config(pdn, PCI_BRIDGE_CONTROL, 2, &cfg); - n += scnprintf(buf+n, len-n, "brdg ctl:%x\n", cfg); - printk(KERN_WARNING "EEH: Bridge control: %04x\n", cfg); - } - - /* Dump out the PCI-X command and status regs */ - cap = pci_find_capability(dev, PCI_CAP_ID_PCIX); - if (cap) { - rtas_read_config(pdn, cap, 4, &cfg); - n += scnprintf(buf+n, len-n, "pcix-cmd:%x\n", cfg); - printk(KERN_WARNING "EEH: PCI-X cmd: %08x\n", cfg); - - rtas_read_config(pdn, cap+4, 4, &cfg); - n += scnprintf(buf+n, len-n, "pcix-stat:%x\n", cfg); - printk(KERN_WARNING "EEH: PCI-X status: %08x\n", cfg); - } - - /* If PCI-E capable, dump PCI-E cap 10, and the AER */ - cap = pci_find_capability(dev, PCI_CAP_ID_EXP); - if (cap) { - n += scnprintf(buf+n, len-n, "pci-e cap10:\n"); - printk(KERN_WARNING - "EEH: PCI-E capabilities and status follow:\n"); - - for (i=0; i<=8; i++) { - rtas_read_config(pdn, cap+4*i, 4, &cfg); - n += scnprintf(buf+n, len-n, "%02x:%x\n", 4*i, cfg); - printk(KERN_WARNING "EEH: PCI-E %02x: %08x\n", i, cfg); - } - - cap = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); - if (cap) { - n += scnprintf(buf+n, len-n, "pci-e AER:\n"); - printk(KERN_WARNING - "EEH: PCI-E AER capability register set follows:\n"); - - for (i=0; i<14; i++) { - rtas_read_config(pdn, cap+4*i, 4, &cfg); - n += scnprintf(buf+n, len-n, "%02x:%x\n", 4*i, cfg); - printk(KERN_WARNING "EEH: PCI-E AER %02x: %08x\n", i, cfg); - } - } - } - - /* Gather status on devices under the bridge */ - if (dev->class >> 16 == PCI_BASE_CLASS_BRIDGE) { - struct device_node *dn; - - for_each_child_of_node(pdn->node, dn) { - pdn = PCI_DN(dn); - if (pdn) - n += gather_pci_data(pdn, buf+n, len-n); - } - } - - return n; -} - -void eeh_slot_error_detail(struct pci_dn *pdn, int severity) -{ - size_t loglen = 0; - pci_regs_buf[0] = 0; - - rtas_pci_enable(pdn, EEH_THAW_MMIO); - loglen = gather_pci_data(pdn, pci_regs_buf, EEH_PCI_REGS_LOG_LEN); - - rtas_slot_error_detail(pdn, severity, pci_regs_buf, loglen); -} - -/** - * read_slot_reset_state - Read the reset state of a device node's slot - * @dn: device node to read - * @rets: array to return results in - */ -static int read_slot_reset_state(struct pci_dn *pdn, int rets[]) -{ - int token, outputs; - int config_addr; - - if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) { - token = ibm_read_slot_reset_state2; - outputs = 4; - } else { - token = ibm_read_slot_reset_state; - rets[2] = 0; /* fake PE Unavailable info */ - outputs = 3; - } - - /* Use PE configuration address, if present */ - config_addr = pdn->eeh_config_addr; - if (pdn->eeh_pe_config_addr) - config_addr = pdn->eeh_pe_config_addr; - - return rtas_call(token, 3, outputs, rets, config_addr, - BUID_HI(pdn->phb->buid), BUID_LO(pdn->phb->buid)); -} - -/** - * eeh_wait_for_slot_status - returns error status of slot - * @pdn pci device node - * @max_wait_msecs maximum number to millisecs to wait - * - * Return negative value if a permanent error, else return - * Partition Endpoint (PE) status value. - * - * If @max_wait_msecs is positive, then this routine will - * sleep until a valid status can be obtained, or until - * the max allowed wait time is exceeded, in which case - * a -2 is returned. - */ -int -eeh_wait_for_slot_status(struct pci_dn *pdn, int max_wait_msecs) -{ - int rc; - int rets[3]; - int mwait; - - while (1) { - rc = read_slot_reset_state(pdn, rets); - if (rc) return rc; - if (rets[1] == 0) return -1; /* EEH is not supported */ - - if (rets[0] != 5) return rets[0]; /* return actual status */ - - if (rets[2] == 0) return -1; /* permanently unavailable */ - - if (max_wait_msecs <= 0) break; - - mwait = rets[2]; - if (mwait <= 0) { - printk (KERN_WARNING - "EEH: Firmware returned bad wait value=%d\n", mwait); - mwait = 1000; - } else if (mwait > 300*1000) { - printk (KERN_WARNING - "EEH: Firmware is taking too long, time=%d\n", mwait); - mwait = 300*1000; - } - max_wait_msecs -= mwait; - msleep (mwait); - } - - printk(KERN_WARNING "EEH: Timed out waiting for slot status\n"); - return -2; -} - -/** - * eeh_token_to_phys - convert EEH address token to phys address - * @token i/o token, should be address in the form 0xA.... - */ -static inline unsigned long eeh_token_to_phys(unsigned long token) -{ - pte_t *ptep; - unsigned long pa; - - ptep = find_linux_pte(init_mm.pgd, token); - if (!ptep) - return token; - pa = pte_pfn(*ptep) << PAGE_SHIFT; - - return pa | (token & (PAGE_SIZE-1)); -} - -/** - * Return the "partitionable endpoint" (pe) under which this device lies - */ -struct device_node * find_device_pe(struct device_node *dn) -{ - while ((dn->parent) && PCI_DN(dn->parent) && - (PCI_DN(dn->parent)->eeh_mode & EEH_MODE_SUPPORTED)) { - dn = dn->parent; - } - return dn; -} - -/** Mark all devices that are children of this device as failed. - * Mark the device driver too, so that it can see the failure - * immediately; this is critical, since some drivers poll - * status registers in interrupts ... If a driver is polling, - * and the slot is frozen, then the driver can deadlock in - * an interrupt context, which is bad. - */ - -static void __eeh_mark_slot(struct device_node *parent, int mode_flag) -{ - struct device_node *dn; - - for_each_child_of_node(parent, dn) { - if (PCI_DN(dn)) { - /* Mark the pci device driver too */ - struct pci_dev *dev = PCI_DN(dn)->pcidev; - - PCI_DN(dn)->eeh_mode |= mode_flag; - - if (dev && dev->driver) - dev->error_state = pci_channel_io_frozen; - - __eeh_mark_slot(dn, mode_flag); - } - } -} - -void eeh_mark_slot (struct device_node *dn, int mode_flag) -{ - struct pci_dev *dev; - dn = find_device_pe (dn); - - /* Back up one, since config addrs might be shared */ - if (!pcibios_find_pci_bus(dn) && PCI_DN(dn->parent)) - dn = dn->parent; - - PCI_DN(dn)->eeh_mode |= mode_flag; - - /* Mark the pci device too */ - dev = PCI_DN(dn)->pcidev; - if (dev) - dev->error_state = pci_channel_io_frozen; - - __eeh_mark_slot(dn, mode_flag); -} - -static void __eeh_clear_slot(struct device_node *parent, int mode_flag) -{ - struct device_node *dn; - - for_each_child_of_node(parent, dn) { - if (PCI_DN(dn)) { - PCI_DN(dn)->eeh_mode &= ~mode_flag; - PCI_DN(dn)->eeh_check_count = 0; - __eeh_clear_slot(dn, mode_flag); - } - } -} - -void eeh_clear_slot (struct device_node *dn, int mode_flag) -{ - unsigned long flags; - raw_spin_lock_irqsave(&confirm_error_lock, flags); - - dn = find_device_pe (dn); - - /* Back up one, since config addrs might be shared */ - if (!pcibios_find_pci_bus(dn) && PCI_DN(dn->parent)) - dn = dn->parent; - - PCI_DN(dn)->eeh_mode &= ~mode_flag; - PCI_DN(dn)->eeh_check_count = 0; - __eeh_clear_slot(dn, mode_flag); - raw_spin_unlock_irqrestore(&confirm_error_lock, flags); -} - -/** - * eeh_dn_check_failure - check if all 1's data is due to EEH slot freeze - * @dn device node - * @dev pci device, if known - * - * Check for an EEH failure for the given device node. Call this - * routine if the result of a read was all 0xff's and you want to - * find out if this is due to an EEH slot freeze. This routine - * will query firmware for the EEH status. - * - * Returns 0 if there has not been an EEH error; otherwise returns - * a non-zero value and queues up a slot isolation event notification. - * - * It is safe to call this routine in an interrupt context. - */ -int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) -{ - int ret; - int rets[3]; - unsigned long flags; - struct pci_dn *pdn; - int rc = 0; - const char *location; - - total_mmio_ffs++; - - if (!eeh_subsystem_enabled) - return 0; - - if (!dn) { - no_dn++; - return 0; - } - dn = find_device_pe(dn); - pdn = PCI_DN(dn); - - /* Access to IO BARs might get this far and still not want checking. */ - if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) || - pdn->eeh_mode & EEH_MODE_NOCHECK) { - ignored_check++; - pr_debug("EEH: Ignored check (%x) for %s %s\n", - pdn->eeh_mode, eeh_pci_name(dev), dn->full_name); - return 0; - } - - if (!pdn->eeh_config_addr && !pdn->eeh_pe_config_addr) { - no_cfg_addr++; - return 0; - } - - /* If we already have a pending isolation event for this - * slot, we know it's bad already, we don't need to check. - * Do this checking under a lock; as multiple PCI devices - * in one slot might report errors simultaneously, and we - * only want one error recovery routine running. - */ - raw_spin_lock_irqsave(&confirm_error_lock, flags); - rc = 1; - if (pdn->eeh_mode & EEH_MODE_ISOLATED) { - pdn->eeh_check_count ++; - if (pdn->eeh_check_count % EEH_MAX_FAILS == 0) { - location = of_get_property(dn, "ibm,loc-code", NULL); - printk (KERN_ERR "EEH: %d reads ignored for recovering device at " - "location=%s driver=%s pci addr=%s\n", - pdn->eeh_check_count, location, - dev->driver->name, eeh_pci_name(dev)); - printk (KERN_ERR "EEH: Might be infinite loop in %s driver\n", - dev->driver->name); - dump_stack(); - } - goto dn_unlock; - } - - /* - * Now test for an EEH failure. This is VERY expensive. - * Note that the eeh_config_addr may be a parent device - * in the case of a device behind a bridge, or it may be - * function zero of a multi-function device. - * In any case they must share a common PHB. - */ - ret = read_slot_reset_state(pdn, rets); - - /* If the call to firmware failed, punt */ - if (ret != 0) { - printk(KERN_WARNING "EEH: read_slot_reset_state() failed; rc=%d dn=%s\n", - ret, dn->full_name); - false_positives++; - pdn->eeh_false_positives ++; - rc = 0; - goto dn_unlock; - } - - /* Note that config-io to empty slots may fail; - * they are empty when they don't have children. */ - if ((rets[0] == 5) && (rets[2] == 0) && (dn->child == NULL)) { - false_positives++; - pdn->eeh_false_positives ++; - rc = 0; - goto dn_unlock; - } - - /* If EEH is not supported on this device, punt. */ - if (rets[1] != 1) { - printk(KERN_WARNING "EEH: event on unsupported device, rc=%d dn=%s\n", - ret, dn->full_name); - false_positives++; - pdn->eeh_false_positives ++; - rc = 0; - goto dn_unlock; - } - - /* If not the kind of error we know about, punt. */ - if (rets[0] != 1 && rets[0] != 2 && rets[0] != 4 && rets[0] != 5) { - false_positives++; - pdn->eeh_false_positives ++; - rc = 0; - goto dn_unlock; - } - - slot_resets++; - - /* Avoid repeated reports of this failure, including problems - * with other functions on this device, and functions under - * bridges. */ - eeh_mark_slot (dn, EEH_MODE_ISOLATED); - raw_spin_unlock_irqrestore(&confirm_error_lock, flags); - - eeh_send_failure_event (dn, dev); - - /* Most EEH events are due to device driver bugs. Having - * a stack trace will help the device-driver authors figure - * out what happened. So print that out. */ - dump_stack(); - return 1; - -dn_unlock: - raw_spin_unlock_irqrestore(&confirm_error_lock, flags); - return rc; -} - -EXPORT_SYMBOL_GPL(eeh_dn_check_failure); - -/** - * eeh_check_failure - check if all 1's data is due to EEH slot freeze - * @token i/o token, should be address in the form 0xA.... - * @val value, should be all 1's (XXX why do we need this arg??) - * - * Check for an EEH failure at the given token address. Call this - * routine if the result of a read was all 0xff's and you want to - * find out if this is due to an EEH slot freeze event. This routine - * will query firmware for the EEH status. - * - * Note this routine is safe to call in an interrupt context. - */ -unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val) -{ - unsigned long addr; - struct pci_dev *dev; - struct device_node *dn; - - /* Finding the phys addr + pci device; this is pretty quick. */ - addr = eeh_token_to_phys((unsigned long __force) token); - dev = pci_get_device_by_addr(addr); - if (!dev) { - no_device++; - return val; - } - - dn = pci_device_to_OF_node(dev); - eeh_dn_check_failure (dn, dev); - - pci_dev_put(dev); - return val; -} - -EXPORT_SYMBOL(eeh_check_failure); - -/* ------------------------------------------------------------- */ -/* The code below deals with error recovery */ - -/** - * rtas_pci_enable - enable MMIO or DMA transfers for this slot - * @pdn pci device node - */ - -int -rtas_pci_enable(struct pci_dn *pdn, int function) -{ - int config_addr; - int rc; - - /* Use PE configuration address, if present */ - config_addr = pdn->eeh_config_addr; - if (pdn->eeh_pe_config_addr) - config_addr = pdn->eeh_pe_config_addr; - - rc = rtas_call(ibm_set_eeh_option, 4, 1, NULL, - config_addr, - BUID_HI(pdn->phb->buid), - BUID_LO(pdn->phb->buid), - function); - - if (rc) - printk(KERN_WARNING "EEH: Unexpected state change %d, err=%d dn=%s\n", - function, rc, pdn->node->full_name); - - rc = eeh_wait_for_slot_status (pdn, PCI_BUS_RESET_WAIT_MSEC); - if ((rc == 4) && (function == EEH_THAW_MMIO)) - return 0; - - return rc; -} - -/** - * rtas_pci_slot_reset - raises/lowers the pci #RST line - * @pdn pci device node - * @state: 1/0 to raise/lower the #RST - * - * Clear the EEH-frozen condition on a slot. This routine - * asserts the PCI #RST line if the 'state' argument is '1', - * and drops the #RST line if 'state is '0'. This routine is - * safe to call in an interrupt context. - * - */ - -static void -rtas_pci_slot_reset(struct pci_dn *pdn, int state) -{ - int config_addr; - int rc; - - BUG_ON (pdn==NULL); - - if (!pdn->phb) { - printk (KERN_WARNING "EEH: in slot reset, device node %s has no phb\n", - pdn->node->full_name); - return; - } - - /* Use PE configuration address, if present */ - config_addr = pdn->eeh_config_addr; - if (pdn->eeh_pe_config_addr) - config_addr = pdn->eeh_pe_config_addr; - - rc = rtas_call(ibm_set_slot_reset,4,1, NULL, - config_addr, - BUID_HI(pdn->phb->buid), - BUID_LO(pdn->phb->buid), - state); - if (rc) - printk (KERN_WARNING "EEH: Unable to reset the failed slot," - " (%d) #RST=%d dn=%s\n", - rc, state, pdn->node->full_name); -} - -/** - * pcibios_set_pcie_slot_reset - Set PCI-E reset state - * @dev: pci device struct - * @state: reset state to enter - * - * Return value: - * 0 if success - **/ -int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state) -{ - struct device_node *dn = pci_device_to_OF_node(dev); - struct pci_dn *pdn = PCI_DN(dn); - - switch (state) { - case pcie_deassert_reset: - rtas_pci_slot_reset(pdn, 0); - break; - case pcie_hot_reset: - rtas_pci_slot_reset(pdn, 1); - break; - case pcie_warm_reset: - rtas_pci_slot_reset(pdn, 3); - break; - default: - return -EINVAL; - }; - - return 0; -} - -/** - * rtas_set_slot_reset -- assert the pci #RST line for 1/4 second - * @pdn: pci device node to be reset. - * - * Return 0 if success, else a non-zero value. - */ - -static void __rtas_set_slot_reset(struct pci_dn *pdn) -{ - struct pci_dev *dev = pdn->pcidev; - - /* Determine type of EEH reset required by device, - * default hot reset or fundamental reset - */ - if (dev && dev->needs_freset) - rtas_pci_slot_reset(pdn, 3); - else - rtas_pci_slot_reset(pdn, 1); - - /* The PCI bus requires that the reset be held high for at least - * a 100 milliseconds. We wait a bit longer 'just in case'. */ - -#define PCI_BUS_RST_HOLD_TIME_MSEC 250 - msleep (PCI_BUS_RST_HOLD_TIME_MSEC); - - /* We might get hit with another EEH freeze as soon as the - * pci slot reset line is dropped. Make sure we don't miss - * these, and clear the flag now. */ - eeh_clear_slot (pdn->node, EEH_MODE_ISOLATED); - - rtas_pci_slot_reset (pdn, 0); - - /* After a PCI slot has been reset, the PCI Express spec requires - * a 1.5 second idle time for the bus to stabilize, before starting - * up traffic. */ -#define PCI_BUS_SETTLE_TIME_MSEC 1800 - msleep (PCI_BUS_SETTLE_TIME_MSEC); -} - -int rtas_set_slot_reset(struct pci_dn *pdn) -{ - int i, rc; - - /* Take three shots at resetting the bus */ - for (i=0; i<3; i++) { - __rtas_set_slot_reset(pdn); - - rc = eeh_wait_for_slot_status(pdn, PCI_BUS_RESET_WAIT_MSEC); - if (rc == 0) - return 0; - - if (rc < 0) { - printk(KERN_ERR "EEH: unrecoverable slot failure %s\n", - pdn->node->full_name); - return -1; - } - printk(KERN_ERR "EEH: bus reset %d failed on slot %s, rc=%d\n", - i+1, pdn->node->full_name, rc); - } - - return -1; -} - -/* ------------------------------------------------------- */ -/** Save and restore of PCI BARs - * - * Although firmware will set up BARs during boot, it doesn't - * set up device BAR's after a device reset, although it will, - * if requested, set up bridge configuration. Thus, we need to - * configure the PCI devices ourselves. - */ - -/** - * __restore_bars - Restore the Base Address Registers - * @pdn: pci device node - * - * Loads the PCI configuration space base address registers, - * the expansion ROM base address, the latency timer, and etc. - * from the saved values in the device node. - */ -static inline void __restore_bars (struct pci_dn *pdn) -{ - int i; - u32 cmd; - - if (NULL==pdn->phb) return; - for (i=4; i<10; i++) { - rtas_write_config(pdn, i*4, 4, pdn->config_space[i]); - } - - /* 12 == Expansion ROM Address */ - rtas_write_config(pdn, 12*4, 4, pdn->config_space[12]); - -#define BYTE_SWAP(OFF) (8*((OFF)/4)+3-(OFF)) -#define SAVED_BYTE(OFF) (((u8 *)(pdn->config_space))[BYTE_SWAP(OFF)]) - - rtas_write_config (pdn, PCI_CACHE_LINE_SIZE, 1, - SAVED_BYTE(PCI_CACHE_LINE_SIZE)); - - rtas_write_config (pdn, PCI_LATENCY_TIMER, 1, - SAVED_BYTE(PCI_LATENCY_TIMER)); - - /* max latency, min grant, interrupt pin and line */ - rtas_write_config(pdn, 15*4, 4, pdn->config_space[15]); - - /* Restore PERR & SERR bits, some devices require it, - don't touch the other command bits */ - rtas_read_config(pdn, PCI_COMMAND, 4, &cmd); - if (pdn->config_space[1] & PCI_COMMAND_PARITY) - cmd |= PCI_COMMAND_PARITY; - else - cmd &= ~PCI_COMMAND_PARITY; - if (pdn->config_space[1] & PCI_COMMAND_SERR) - cmd |= PCI_COMMAND_SERR; - else - cmd &= ~PCI_COMMAND_SERR; - rtas_write_config(pdn, PCI_COMMAND, 4, cmd); -} - -/** - * eeh_restore_bars - restore the PCI config space info - * - * This routine performs a recursive walk to the children - * of this device as well. - */ -void eeh_restore_bars(struct pci_dn *pdn) -{ - struct device_node *dn; - if (!pdn) - return; - - if ((pdn->eeh_mode & EEH_MODE_SUPPORTED) && !IS_BRIDGE(pdn->class_code)) - __restore_bars (pdn); - - for_each_child_of_node(pdn->node, dn) - eeh_restore_bars (PCI_DN(dn)); -} - -/** - * eeh_save_bars - save device bars - * - * Save the values of the device bars. Unlike the restore - * routine, this routine is *not* recursive. This is because - * PCI devices are added individuallly; but, for the restore, - * an entire slot is reset at a time. - */ -static void eeh_save_bars(struct pci_dn *pdn) -{ - int i; - - if (!pdn ) - return; - - for (i = 0; i < 16; i++) - rtas_read_config(pdn, i * 4, 4, &pdn->config_space[i]); -} - -void -rtas_configure_bridge(struct pci_dn *pdn) -{ - int config_addr; - int rc; - - /* Use PE configuration address, if present */ - config_addr = pdn->eeh_config_addr; - if (pdn->eeh_pe_config_addr) - config_addr = pdn->eeh_pe_config_addr; - - rc = rtas_call(ibm_configure_bridge,3,1, NULL, - config_addr, - BUID_HI(pdn->phb->buid), - BUID_LO(pdn->phb->buid)); - if (rc) { - printk (KERN_WARNING "EEH: Unable to configure device bridge (%d) for %s\n", - rc, pdn->node->full_name); - } -} - -/* ------------------------------------------------------------- */ -/* The code below deals with enabling EEH for devices during the - * early boot sequence. EEH must be enabled before any PCI probing - * can be done. - */ - -#define EEH_ENABLE 1 - -struct eeh_early_enable_info { - unsigned int buid_hi; - unsigned int buid_lo; -}; - -static int get_pe_addr (int config_addr, - struct eeh_early_enable_info *info) -{ - unsigned int rets[3]; - int ret; - - /* Use latest config-addr token on power6 */ - if (ibm_get_config_addr_info2 != RTAS_UNKNOWN_SERVICE) { - /* Make sure we have a PE in hand */ - ret = rtas_call (ibm_get_config_addr_info2, 4, 2, rets, - config_addr, info->buid_hi, info->buid_lo, 1); - if (ret || (rets[0]==0)) - return 0; - - ret = rtas_call (ibm_get_config_addr_info2, 4, 2, rets, - config_addr, info->buid_hi, info->buid_lo, 0); - if (ret) - return 0; - return rets[0]; - } - - /* Use older config-addr token on power5 */ - if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) { - ret = rtas_call (ibm_get_config_addr_info, 4, 2, rets, - config_addr, info->buid_hi, info->buid_lo, 0); - if (ret) - return 0; - return rets[0]; - } - return 0; -} - -/* Enable eeh for the given device node. */ -static void *early_enable_eeh(struct device_node *dn, void *data) -{ - unsigned int rets[3]; - struct eeh_early_enable_info *info = data; - int ret; - const u32 *class_code = of_get_property(dn, "class-code", NULL); - const u32 *vendor_id = of_get_property(dn, "vendor-id", NULL); - const u32 *device_id = of_get_property(dn, "device-id", NULL); - const u32 *regs; - int enable; - struct pci_dn *pdn = PCI_DN(dn); - - pdn->class_code = 0; - pdn->eeh_mode = 0; - pdn->eeh_check_count = 0; - pdn->eeh_freeze_count = 0; - pdn->eeh_false_positives = 0; - - if (!of_device_is_available(dn)) - return NULL; - - /* Ignore bad nodes. */ - if (!class_code || !vendor_id || !device_id) - return NULL; - - /* There is nothing to check on PCI to ISA bridges */ - if (dn->type && !strcmp(dn->type, "isa")) { - pdn->eeh_mode |= EEH_MODE_NOCHECK; - return NULL; - } - pdn->class_code = *class_code; - - /* Ok... see if this device supports EEH. Some do, some don't, - * and the only way to find out is to check each and every one. */ - regs = of_get_property(dn, "reg", NULL); - if (regs) { - /* First register entry is addr (00BBSS00) */ - /* Try to enable eeh */ - ret = rtas_call(ibm_set_eeh_option, 4, 1, NULL, - regs[0], info->buid_hi, info->buid_lo, - EEH_ENABLE); - - enable = 0; - if (ret == 0) { - pdn->eeh_config_addr = regs[0]; - - /* If the newer, better, ibm,get-config-addr-info is supported, - * then use that instead. */ - pdn->eeh_pe_config_addr = get_pe_addr(pdn->eeh_config_addr, info); - - /* Some older systems (Power4) allow the - * ibm,set-eeh-option call to succeed even on nodes - * where EEH is not supported. Verify support - * explicitly. */ - ret = read_slot_reset_state(pdn, rets); - if ((ret == 0) && (rets[1] == 1)) - enable = 1; - } - - if (enable) { - eeh_subsystem_enabled = 1; - pdn->eeh_mode |= EEH_MODE_SUPPORTED; - - pr_debug("EEH: %s: eeh enabled, config=%x pe_config=%x\n", - dn->full_name, pdn->eeh_config_addr, - pdn->eeh_pe_config_addr); - } else { - - /* This device doesn't support EEH, but it may have an - * EEH parent, in which case we mark it as supported. */ - if (dn->parent && PCI_DN(dn->parent) - && (PCI_DN(dn->parent)->eeh_mode & EEH_MODE_SUPPORTED)) { - /* Parent supports EEH. */ - pdn->eeh_mode |= EEH_MODE_SUPPORTED; - pdn->eeh_config_addr = PCI_DN(dn->parent)->eeh_config_addr; - return NULL; - } - } - } else { - printk(KERN_WARNING "EEH: %s: unable to get reg property.\n", - dn->full_name); - } - - eeh_save_bars(pdn); - return NULL; -} - -/* - * Initialize EEH by trying to enable it for all of the adapters in the system. - * As a side effect we can determine here if eeh is supported at all. - * Note that we leave EEH on so failed config cycles won't cause a machine - * check. If a user turns off EEH for a particular adapter they are really - * telling Linux to ignore errors. Some hardware (e.g. POWER5) won't - * grant access to a slot if EEH isn't enabled, and so we always enable - * EEH for all slots/all devices. - * - * The eeh-force-off option disables EEH checking globally, for all slots. - * Even if force-off is set, the EEH hardware is still enabled, so that - * newer systems can boot. - */ -void __init eeh_init(void) -{ - struct device_node *phb, *np; - struct eeh_early_enable_info info; - - raw_spin_lock_init(&confirm_error_lock); - spin_lock_init(&slot_errbuf_lock); - - np = of_find_node_by_path("/rtas"); - if (np == NULL) - return; - - ibm_set_eeh_option = rtas_token("ibm,set-eeh-option"); - ibm_set_slot_reset = rtas_token("ibm,set-slot-reset"); - ibm_read_slot_reset_state2 = rtas_token("ibm,read-slot-reset-state2"); - ibm_read_slot_reset_state = rtas_token("ibm,read-slot-reset-state"); - ibm_slot_error_detail = rtas_token("ibm,slot-error-detail"); - ibm_get_config_addr_info = rtas_token("ibm,get-config-addr-info"); - ibm_get_config_addr_info2 = rtas_token("ibm,get-config-addr-info2"); - ibm_configure_bridge = rtas_token ("ibm,configure-bridge"); - - if (ibm_set_eeh_option == RTAS_UNKNOWN_SERVICE) - return; - - eeh_error_buf_size = rtas_token("rtas-error-log-max"); - if (eeh_error_buf_size == RTAS_UNKNOWN_SERVICE) { - eeh_error_buf_size = 1024; - } - if (eeh_error_buf_size > RTAS_ERROR_LOG_MAX) { - printk(KERN_WARNING "EEH: rtas-error-log-max is bigger than allocated " - "buffer ! (%d vs %d)", eeh_error_buf_size, RTAS_ERROR_LOG_MAX); - eeh_error_buf_size = RTAS_ERROR_LOG_MAX; - } - - /* Enable EEH for all adapters. Note that eeh requires buid's */ - for (phb = of_find_node_by_name(NULL, "pci"); phb; - phb = of_find_node_by_name(phb, "pci")) { - unsigned long buid; - - buid = get_phb_buid(phb); - if (buid == 0 || PCI_DN(phb) == NULL) - continue; - - info.buid_lo = BUID_LO(buid); - info.buid_hi = BUID_HI(buid); - traverse_pci_devices(phb, early_enable_eeh, &info); - } - - if (eeh_subsystem_enabled) - printk(KERN_INFO "EEH: PCI Enhanced I/O Error Handling Enabled\n"); - else - printk(KERN_WARNING "EEH: No capable adapters found\n"); -} - -/** - * eeh_add_device_early - enable EEH for the indicated device_node - * @dn: device node for which to set up EEH - * - * This routine must be used to perform EEH initialization for PCI - * devices that were added after system boot (e.g. hotplug, dlpar). - * This routine must be called before any i/o is performed to the - * adapter (inluding any config-space i/o). - * Whether this actually enables EEH or not for this device depends - * on the CEC architecture, type of the device, on earlier boot - * command-line arguments & etc. - */ -static void eeh_add_device_early(struct device_node *dn) -{ - struct pci_controller *phb; - struct eeh_early_enable_info info; - - if (!dn || !PCI_DN(dn)) - return; - phb = PCI_DN(dn)->phb; - - /* USB Bus children of PCI devices will not have BUID's */ - if (NULL == phb || 0 == phb->buid) - return; - - info.buid_hi = BUID_HI(phb->buid); - info.buid_lo = BUID_LO(phb->buid); - early_enable_eeh(dn, &info); -} - -void eeh_add_device_tree_early(struct device_node *dn) -{ - struct device_node *sib; - - for_each_child_of_node(dn, sib) - eeh_add_device_tree_early(sib); - eeh_add_device_early(dn); -} -EXPORT_SYMBOL_GPL(eeh_add_device_tree_early); - -/** - * eeh_add_device_late - perform EEH initialization for the indicated pci device - * @dev: pci device for which to set up EEH - * - * This routine must be used to complete EEH initialization for PCI - * devices that were added after system boot (e.g. hotplug, dlpar). - */ -static void eeh_add_device_late(struct pci_dev *dev) -{ - struct device_node *dn; - struct pci_dn *pdn; - - if (!dev || !eeh_subsystem_enabled) - return; - - pr_debug("EEH: Adding device %s\n", pci_name(dev)); - - dn = pci_device_to_OF_node(dev); - pdn = PCI_DN(dn); - if (pdn->pcidev == dev) { - pr_debug("EEH: Already referenced !\n"); - return; - } - WARN_ON(pdn->pcidev); - - pci_dev_get (dev); - pdn->pcidev = dev; - - pci_addr_cache_insert_device(dev); - eeh_sysfs_add_device(dev); -} - -void eeh_add_device_tree_late(struct pci_bus *bus) -{ - struct pci_dev *dev; - - list_for_each_entry(dev, &bus->devices, bus_list) { - eeh_add_device_late(dev); - if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { - struct pci_bus *subbus = dev->subordinate; - if (subbus) - eeh_add_device_tree_late(subbus); - } - } -} -EXPORT_SYMBOL_GPL(eeh_add_device_tree_late); - -/** - * eeh_remove_device - undo EEH setup for the indicated pci device - * @dev: pci device to be removed - * - * This routine should be called when a device is removed from - * a running system (e.g. by hotplug or dlpar). It unregisters - * the PCI device from the EEH subsystem. I/O errors affecting - * this device will no longer be detected after this call; thus, - * i/o errors affecting this slot may leave this device unusable. - */ -static void eeh_remove_device(struct pci_dev *dev) -{ - struct device_node *dn; - if (!dev || !eeh_subsystem_enabled) - return; - - /* Unregister the device with the EEH/PCI address search system */ - pr_debug("EEH: Removing device %s\n", pci_name(dev)); - - dn = pci_device_to_OF_node(dev); - if (PCI_DN(dn)->pcidev == NULL) { - pr_debug("EEH: Not referenced !\n"); - return; - } - PCI_DN(dn)->pcidev = NULL; - pci_dev_put (dev); - - pci_addr_cache_remove_device(dev); - eeh_sysfs_remove_device(dev); -} - -void eeh_remove_bus_device(struct pci_dev *dev) -{ - struct pci_bus *bus = dev->subordinate; - struct pci_dev *child, *tmp; - - eeh_remove_device(dev); - - if (bus && dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { - list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) - eeh_remove_bus_device(child); - } -} -EXPORT_SYMBOL_GPL(eeh_remove_bus_device); - -static int proc_eeh_show(struct seq_file *m, void *v) -{ - if (0 == eeh_subsystem_enabled) { - seq_printf(m, "EEH Subsystem is globally disabled\n"); - seq_printf(m, "eeh_total_mmio_ffs=%ld\n", total_mmio_ffs); - } else { - seq_printf(m, "EEH Subsystem is enabled\n"); - seq_printf(m, - "no device=%ld\n" - "no device node=%ld\n" - "no config address=%ld\n" - "check not wanted=%ld\n" - "eeh_total_mmio_ffs=%ld\n" - "eeh_false_positives=%ld\n" - "eeh_slot_resets=%ld\n", - no_device, no_dn, no_cfg_addr, - ignored_check, total_mmio_ffs, - false_positives, - slot_resets); - } - - return 0; -} - -static int proc_eeh_open(struct inode *inode, struct file *file) -{ - return single_open(file, proc_eeh_show, NULL); -} - -static const struct file_operations proc_eeh_operations = { - .open = proc_eeh_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init eeh_init_proc(void) -{ - if (machine_is(pseries)) - proc_create("ppc64/eeh", 0, NULL, &proc_eeh_operations); - return 0; -} -__initcall(eeh_init_proc); |