| /* |
| * eeh.c |
| * Copyright (C) 2001 Dave Engebretsen & Todd Inglett IBM Corporation |
| * |
| * 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 |
| */ |
| |
| #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 <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> |
| |
| #undef DEBUG |
| |
| /** 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 has occurred, we assume it |
| * is broken and panic. This sets the threshold for how many read |
| * attempts we allow before panicking. |
| */ |
| #define EEH_MAX_FAILS 100000 |
| |
| /* 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; |
| |
| int eeh_subsystem_enabled; |
| EXPORT_SYMBOL(eeh_subsystem_enabled); |
| |
| /* Lock to avoid races due to multiple reports of an error */ |
| static DEFINE_SPINLOCK(confirm_error_lock); |
| |
| /* Buffer for reporting slot-error-detail rtas calls */ |
| static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX]; |
| static DEFINE_SPINLOCK(slot_errbuf_lock); |
| static int eeh_error_buf_size; |
| |
| /* System monitoring statistics */ |
| static DEFINE_PER_CPU(unsigned long, no_device); |
| static DEFINE_PER_CPU(unsigned long, no_dn); |
| static DEFINE_PER_CPU(unsigned long, no_cfg_addr); |
| static DEFINE_PER_CPU(unsigned long, ignored_check); |
| static DEFINE_PER_CPU(unsigned long, total_mmio_ffs); |
| static DEFINE_PER_CPU(unsigned long, false_positives); |
| static DEFINE_PER_CPU(unsigned long, ignored_failures); |
| static DEFINE_PER_CPU(unsigned long, slot_resets); |
| |
| /* --------------------------------------------------------------- */ |
| /* Below lies the EEH event infrastructure */ |
| |
| void eeh_slot_error_detail (struct pci_dn *pdn, int severity) |
| { |
| 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), NULL, 0, |
| 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); |
| } |
| |
| /** |
| * 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_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 peers 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 *dn, int mode_flag) |
| { |
| while (dn) { |
| if (PCI_DN(dn)) { |
| PCI_DN(dn)->eeh_mode |= mode_flag; |
| |
| /* Mark the pci device driver too */ |
| struct pci_dev *dev = PCI_DN(dn)->pcidev; |
| if (dev && dev->driver) |
| dev->error_state = pci_channel_io_frozen; |
| |
| if (dn->child) |
| __eeh_mark_slot (dn->child, mode_flag); |
| } |
| dn = dn->sibling; |
| } |
| } |
| |
| void eeh_mark_slot (struct device_node *dn, int mode_flag) |
| { |
| dn = find_device_pe (dn); |
| PCI_DN(dn)->eeh_mode |= mode_flag; |
| __eeh_mark_slot (dn->child, mode_flag); |
| } |
| |
| static void __eeh_clear_slot (struct device_node *dn, int mode_flag) |
| { |
| while (dn) { |
| if (PCI_DN(dn)) { |
| PCI_DN(dn)->eeh_mode &= ~mode_flag; |
| PCI_DN(dn)->eeh_check_count = 0; |
| if (dn->child) |
| __eeh_clear_slot (dn->child, mode_flag); |
| } |
| dn = dn->sibling; |
| } |
| } |
| |
| void eeh_clear_slot (struct device_node *dn, int mode_flag) |
| { |
| unsigned long flags; |
| spin_lock_irqsave(&confirm_error_lock, flags); |
| dn = find_device_pe (dn); |
| PCI_DN(dn)->eeh_mode &= ~mode_flag; |
| PCI_DN(dn)->eeh_check_count = 0; |
| __eeh_clear_slot (dn->child, mode_flag); |
| 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; |
| enum pci_channel_state state; |
| int rc = 0; |
| |
| __get_cpu_var(total_mmio_ffs)++; |
| |
| if (!eeh_subsystem_enabled) |
| return 0; |
| |
| if (!dn) { |
| __get_cpu_var(no_dn)++; |
| return 0; |
| } |
| 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) { |
| __get_cpu_var(ignored_check)++; |
| #ifdef DEBUG |
| printk ("EEH:ignored check (%x) for %s %s\n", |
| pdn->eeh_mode, pci_name (dev), dn->full_name); |
| #endif |
| return 0; |
| } |
| |
| if (!pdn->eeh_config_addr && !pdn->eeh_pe_config_addr) { |
| __get_cpu_var(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. |
| */ |
| 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) { |
| printk (KERN_ERR "EEH: Device driver ignored %d bad reads, panicing\n", |
| pdn->eeh_check_count); |
| dump_stack(); |
| |
| /* re-read the slot reset state */ |
| if (read_slot_reset_state(pdn, rets) != 0) |
| rets[0] = -1; /* reset state unknown */ |
| |
| /* If we are here, then we hit an infinite loop. Stop. */ |
| panic("EEH: MMIO halt (%d) on device:%s\n", rets[0], pci_name(dev)); |
| } |
| 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); |
| __get_cpu_var(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); |
| __get_cpu_var(false_positives)++; |
| rc = 0; |
| goto dn_unlock; |
| } |
| |
| /* If not the kind of error we know about, punt. */ |
| if (rets[0] != 2 && rets[0] != 4 && rets[0] != 5) { |
| __get_cpu_var(false_positives)++; |
| rc = 0; |
| goto dn_unlock; |
| } |
| |
| /* Note that config-io to empty slots may fail; |
| * we recognize empty because they don't have children. */ |
| if ((rets[0] == 5) && (dn->child == NULL)) { |
| __get_cpu_var(false_positives)++; |
| rc = 0; |
| goto dn_unlock; |
| } |
| |
| __get_cpu_var(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); |
| spin_unlock_irqrestore(&confirm_error_lock, flags); |
| |
| state = pci_channel_io_normal; |
| if ((rets[0] == 2) || (rets[0] == 4)) |
| state = pci_channel_io_frozen; |
| if (rets[0] == 5) |
| state = pci_channel_io_perm_failure; |
| eeh_send_failure_event (dn, dev, state, rets[2]); |
| |
| /* 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. */ |
| if (rets[0] != 5) dump_stack(); |
| return 1; |
| |
| dn_unlock: |
| 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) { |
| __get_cpu_var(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 */ |
| |
| /** Return negative value if a permanent error, else return |
| * a number of milliseconds to wait until the PCI slot is |
| * ready to be used. |
| */ |
| static int |
| eeh_slot_availability(struct pci_dn *pdn) |
| { |
| int rc; |
| int rets[3]; |
| |
| rc = read_slot_reset_state(pdn, rets); |
| |
| if (rc) return rc; |
| |
| if (rets[1] == 0) return -1; /* EEH is not supported */ |
| if (rets[0] == 0) return 0; /* Oll Korrect */ |
| if (rets[0] == 5) { |
| if (rets[2] == 0) return -1; /* permanently unavailable */ |
| return rets[2]; /* number of millisecs to wait */ |
| } |
| return -1; |
| } |
| |
| /** rtas_pci_slot_reset raises/lowers the pci #RST line |
| * 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); |
| return; |
| } |
| } |
| |
| /** rtas_set_slot_reset -- assert the pci #RST line for 1/4 second |
| * dn -- device node to be reset. |
| */ |
| |
| void |
| rtas_set_slot_reset(struct pci_dn *pdn) |
| { |
| int i, rc; |
| |
| 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); |
| |
| /* Now double check with the firmware to make sure the device is |
| * ready to be used; if not, wait for recovery. */ |
| for (i=0; i<10; i++) { |
| rc = eeh_slot_availability (pdn); |
| if (rc <= 0) break; |
| |
| msleep (rc+100); |
| } |
| } |
| |
| /* ------------------------------------------------------- */ |
| /** 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 |
| * 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; |
| |
| 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]); |
| } |
| |
| /** |
| * 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_is_bridge) |
| __restore_bars (pdn); |
| |
| dn = pdn->node->child; |
| while (dn) { |
| eeh_restore_bars (PCI_DN(dn)); |
| dn = dn->sibling; |
| } |
| } |
| |
| /** |
| * 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. |
| */ |
| void eeh_save_bars(struct pci_dev * pdev, struct pci_dn *pdn) |
| { |
| int i; |
| |
| if (!pdev || !pdn ) |
| return; |
| |
| for (i = 0; i < 16; i++) |
| pci_read_config_dword(pdev, i * 4, &pdn->config_space[i]); |
| |
| if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE) |
| pdn->eeh_is_bridge = 1; |
| } |
| |
| void |
| rtas_configure_bridge(struct pci_dn *pdn) |
| { |
| int config_addr; |
| int token = rtas_token ("ibm,configure-bridge"); |
| int rc; |
| |
| if (token == RTAS_UNKNOWN_SERVICE) |
| 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(token,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; |
| }; |
| |
| /* Enable eeh for the given device node. */ |
| static void *early_enable_eeh(struct device_node *dn, void *data) |
| { |
| struct eeh_early_enable_info *info = data; |
| int ret; |
| char *status = get_property(dn, "status", NULL); |
| u32 *class_code = (u32 *)get_property(dn, "class-code", NULL); |
| u32 *vendor_id = (u32 *)get_property(dn, "vendor-id", NULL); |
| u32 *device_id = (u32 *)get_property(dn, "device-id", NULL); |
| u32 *regs; |
| int enable; |
| struct pci_dn *pdn = PCI_DN(dn); |
| |
| pdn->eeh_mode = 0; |
| pdn->eeh_check_count = 0; |
| pdn->eeh_freeze_count = 0; |
| |
| if (status && strcmp(status, "ok") != 0) |
| return NULL; /* ignore devices with bad status */ |
| |
| /* 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; |
| } |
| |
| /* |
| * Now decide if we are going to "Disable" EEH checking |
| * for this device. We still run with the EEH hardware active, |
| * but we won't be checking for ff's. This means a driver |
| * could return bad data (very bad!), an interrupt handler could |
| * hang waiting on status bits that won't change, etc. |
| * But there are a few cases like display devices that make sense. |
| */ |
| enable = 1; /* i.e. we will do checking */ |
| #if 0 |
| if ((*class_code >> 16) == PCI_BASE_CLASS_DISPLAY) |
| enable = 0; |
| #endif |
| |
| if (!enable) |
| pdn->eeh_mode |= EEH_MODE_NOCHECK; |
| |
| /* 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 = (u32 *)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); |
| |
| if (ret == 0) { |
| eeh_subsystem_enabled = 1; |
| pdn->eeh_mode |= EEH_MODE_SUPPORTED; |
| 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 = 0; |
| if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) { |
| unsigned int rets[2]; |
| ret = rtas_call (ibm_get_config_addr_info, 4, 2, rets, |
| pdn->eeh_config_addr, |
| info->buid_hi, info->buid_lo, |
| 0); |
| if (ret == 0) |
| pdn->eeh_pe_config_addr = rets[0]; |
| } |
| #ifdef DEBUG |
| printk(KERN_DEBUG "EEH: %s: eeh enabled, config=%x pe_config=%x\n", |
| dn->full_name, pdn->eeh_config_addr, pdn->eeh_pe_config_addr); |
| #endif |
| } 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); |
| } |
| |
| 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; |
| |
| 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"); |
| |
| 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. |
| */ |
| 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); |
| } |
| EXPORT_SYMBOL_GPL(eeh_add_device_early); |
| |
| void eeh_add_device_tree_early(struct device_node *dn) |
| { |
| struct device_node *sib; |
| for (sib = dn->child; sib; sib = sib->sibling) |
| 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). |
| */ |
| void eeh_add_device_late(struct pci_dev *dev) |
| { |
| struct device_node *dn; |
| struct pci_dn *pdn; |
| |
| if (!dev || !eeh_subsystem_enabled) |
| return; |
| |
| #ifdef DEBUG |
| printk(KERN_DEBUG "EEH: adding device %s\n", pci_name(dev)); |
| #endif |
| |
| pci_dev_get (dev); |
| dn = pci_device_to_OF_node(dev); |
| pdn = PCI_DN(dn); |
| pdn->pcidev = dev; |
| |
| pci_addr_cache_insert_device (dev); |
| eeh_save_bars(dev, pdn); |
| } |
| EXPORT_SYMBOL_GPL(eeh_add_device_late); |
| |
| /** |
| * eeh_remove_device - undo EEH setup for the indicated pci device |
| * @dev: pci device to be removed |
| * |
| * This routine should be when a device is removed from a running |
| * system (e.g. by hotplug or dlpar). |
| */ |
| 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 */ |
| #ifdef DEBUG |
| printk(KERN_DEBUG "EEH: remove device %s\n", pci_name(dev)); |
| #endif |
| pci_addr_cache_remove_device(dev); |
| |
| dn = pci_device_to_OF_node(dev); |
| PCI_DN(dn)->pcidev = NULL; |
| pci_dev_put (dev); |
| } |
| EXPORT_SYMBOL_GPL(eeh_remove_device); |
| |
| void eeh_remove_bus_device(struct pci_dev *dev) |
| { |
| eeh_remove_device(dev); |
| if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { |
| struct pci_bus *bus = dev->subordinate; |
| struct list_head *ln; |
| if (!bus) |
| return; |
| for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) { |
| struct pci_dev *pdev = pci_dev_b(ln); |
| if (pdev) |
| eeh_remove_bus_device(pdev); |
| } |
| } |
| } |
| EXPORT_SYMBOL_GPL(eeh_remove_bus_device); |
| |
| static int proc_eeh_show(struct seq_file *m, void *v) |
| { |
| unsigned int cpu; |
| unsigned long ffs = 0, positives = 0, failures = 0; |
| unsigned long resets = 0; |
| unsigned long no_dev = 0, no_dn = 0, no_cfg = 0, no_check = 0; |
| |
| for_each_cpu(cpu) { |
| ffs += per_cpu(total_mmio_ffs, cpu); |
| positives += per_cpu(false_positives, cpu); |
| failures += per_cpu(ignored_failures, cpu); |
| resets += per_cpu(slot_resets, cpu); |
| no_dev += per_cpu(no_device, cpu); |
| no_dn += per_cpu(no_dn, cpu); |
| no_cfg += per_cpu(no_cfg_addr, cpu); |
| no_check += per_cpu(ignored_check, cpu); |
| } |
| |
| if (0 == eeh_subsystem_enabled) { |
| seq_printf(m, "EEH Subsystem is globally disabled\n"); |
| seq_printf(m, "eeh_total_mmio_ffs=%ld\n", 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_ignored_failures=%ld\n" |
| "eeh_slot_resets=%ld\n", |
| no_dev, no_dn, no_cfg, no_check, |
| ffs, positives, failures, resets); |
| } |
| |
| return 0; |
| } |
| |
| static int proc_eeh_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, proc_eeh_show, NULL); |
| } |
| |
| static 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) |
| { |
| struct proc_dir_entry *e; |
| |
| if (platform_is_pseries()) { |
| e = create_proc_entry("ppc64/eeh", 0, NULL); |
| if (e) |
| e->proc_fops = &proc_eeh_operations; |
| } |
| |
| return 0; |
| } |
| __initcall(eeh_init_proc); |