forked from luck/tmp_suning_uos_patched
938 lines
28 KiB
C
938 lines
28 KiB
C
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/*
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* eeh.c
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* Copyright (C) 2001 Dave Engebretsen & Todd Inglett IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/bootmem.h>
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#include <linux/init.h>
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#include <linux/list.h>
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#include <linux/mm.h>
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#include <linux/notifier.h>
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#include <linux/pci.h>
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#include <linux/proc_fs.h>
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#include <linux/rbtree.h>
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#include <linux/seq_file.h>
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#include <linux/spinlock.h>
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#include <asm/eeh.h>
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#include <asm/io.h>
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#include <asm/machdep.h>
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#include <asm/rtas.h>
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#include <asm/atomic.h>
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#include <asm/systemcfg.h>
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#include "pci.h"
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#undef DEBUG
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/** Overview:
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* EEH, or "Extended Error Handling" is a PCI bridge technology for
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* dealing with PCI bus errors that can't be dealt with within the
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* usual PCI framework, except by check-stopping the CPU. Systems
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* that are designed for high-availability/reliability cannot afford
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* to crash due to a "mere" PCI error, thus the need for EEH.
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* An EEH-capable bridge operates by converting a detected error
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* into a "slot freeze", taking the PCI adapter off-line, making
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* the slot behave, from the OS'es point of view, as if the slot
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* were "empty": all reads return 0xff's and all writes are silently
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* ignored. EEH slot isolation events can be triggered by parity
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* errors on the address or data busses (e.g. during posted writes),
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* which in turn might be caused by dust, vibration, humidity,
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* radioactivity or plain-old failed hardware.
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*
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* Note, however, that one of the leading causes of EEH slot
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* freeze events are buggy device drivers, buggy device microcode,
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* or buggy device hardware. This is because any attempt by the
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* device to bus-master data to a memory address that is not
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* assigned to the device will trigger a slot freeze. (The idea
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* is to prevent devices-gone-wild from corrupting system memory).
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* Buggy hardware/drivers will have a miserable time co-existing
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* with EEH.
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*
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* Ideally, a PCI device driver, when suspecting that an isolation
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* event has occured (e.g. by reading 0xff's), will then ask EEH
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* whether this is the case, and then take appropriate steps to
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* reset the PCI slot, the PCI device, and then resume operations.
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* However, until that day, the checking is done here, with the
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* eeh_check_failure() routine embedded in the MMIO macros. If
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* the slot is found to be isolated, an "EEH Event" is synthesized
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* and sent out for processing.
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*/
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/** Bus Unit ID macros; get low and hi 32-bits of the 64-bit BUID */
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#define BUID_HI(buid) ((buid) >> 32)
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#define BUID_LO(buid) ((buid) & 0xffffffff)
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/* EEH event workqueue setup. */
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static DEFINE_SPINLOCK(eeh_eventlist_lock);
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LIST_HEAD(eeh_eventlist);
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static void eeh_event_handler(void *);
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DECLARE_WORK(eeh_event_wq, eeh_event_handler, NULL);
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static struct notifier_block *eeh_notifier_chain;
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/*
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* If a device driver keeps reading an MMIO register in an interrupt
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* handler after a slot isolation event has occurred, we assume it
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* is broken and panic. This sets the threshold for how many read
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* attempts we allow before panicking.
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*/
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#define EEH_MAX_FAILS 1000
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static atomic_t eeh_fail_count;
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/* RTAS tokens */
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static int ibm_set_eeh_option;
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static int ibm_set_slot_reset;
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static int ibm_read_slot_reset_state;
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static int ibm_read_slot_reset_state2;
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static int ibm_slot_error_detail;
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static int eeh_subsystem_enabled;
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/* Buffer for reporting slot-error-detail rtas calls */
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static unsigned char slot_errbuf[RTAS_ERROR_LOG_MAX];
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static DEFINE_SPINLOCK(slot_errbuf_lock);
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static int eeh_error_buf_size;
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/* System monitoring statistics */
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static DEFINE_PER_CPU(unsigned long, total_mmio_ffs);
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static DEFINE_PER_CPU(unsigned long, false_positives);
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static DEFINE_PER_CPU(unsigned long, ignored_failures);
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static DEFINE_PER_CPU(unsigned long, slot_resets);
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/**
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* The pci address cache subsystem. This subsystem places
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* PCI device address resources into a red-black tree, sorted
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* according to the address range, so that given only an i/o
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* address, the corresponding PCI device can be **quickly**
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* found. It is safe to perform an address lookup in an interrupt
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* context; this ability is an important feature.
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*
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* Currently, the only customer of this code is the EEH subsystem;
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* thus, this code has been somewhat tailored to suit EEH better.
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* In particular, the cache does *not* hold the addresses of devices
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* for which EEH is not enabled.
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*
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* (Implementation Note: The RB tree seems to be better/faster
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* than any hash algo I could think of for this problem, even
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* with the penalty of slow pointer chases for d-cache misses).
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*/
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struct pci_io_addr_range
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{
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struct rb_node rb_node;
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unsigned long addr_lo;
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unsigned long addr_hi;
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struct pci_dev *pcidev;
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unsigned int flags;
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};
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static struct pci_io_addr_cache
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{
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struct rb_root rb_root;
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spinlock_t piar_lock;
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} pci_io_addr_cache_root;
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static inline struct pci_dev *__pci_get_device_by_addr(unsigned long addr)
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{
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struct rb_node *n = pci_io_addr_cache_root.rb_root.rb_node;
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while (n) {
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struct pci_io_addr_range *piar;
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piar = rb_entry(n, struct pci_io_addr_range, rb_node);
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if (addr < piar->addr_lo) {
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n = n->rb_left;
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} else {
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if (addr > piar->addr_hi) {
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n = n->rb_right;
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} else {
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pci_dev_get(piar->pcidev);
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return piar->pcidev;
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}
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}
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}
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return NULL;
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}
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/**
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* pci_get_device_by_addr - Get device, given only address
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* @addr: mmio (PIO) phys address or i/o port number
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*
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* Given an mmio phys address, or a port number, find a pci device
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* that implements this address. Be sure to pci_dev_put the device
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* when finished. I/O port numbers are assumed to be offset
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* from zero (that is, they do *not* have pci_io_addr added in).
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* It is safe to call this function within an interrupt.
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*/
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static struct pci_dev *pci_get_device_by_addr(unsigned long addr)
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{
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struct pci_dev *dev;
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unsigned long flags;
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spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
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dev = __pci_get_device_by_addr(addr);
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spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
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return dev;
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}
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#ifdef DEBUG
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/*
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* Handy-dandy debug print routine, does nothing more
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* than print out the contents of our addr cache.
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*/
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static void pci_addr_cache_print(struct pci_io_addr_cache *cache)
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{
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struct rb_node *n;
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int cnt = 0;
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n = rb_first(&cache->rb_root);
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while (n) {
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struct pci_io_addr_range *piar;
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piar = rb_entry(n, struct pci_io_addr_range, rb_node);
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printk(KERN_DEBUG "PCI: %s addr range %d [%lx-%lx]: %s %s\n",
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(piar->flags & IORESOURCE_IO) ? "i/o" : "mem", cnt,
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piar->addr_lo, piar->addr_hi, pci_name(piar->pcidev),
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pci_pretty_name(piar->pcidev));
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cnt++;
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n = rb_next(n);
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}
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}
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#endif
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/* Insert address range into the rb tree. */
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static struct pci_io_addr_range *
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pci_addr_cache_insert(struct pci_dev *dev, unsigned long alo,
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unsigned long ahi, unsigned int flags)
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{
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struct rb_node **p = &pci_io_addr_cache_root.rb_root.rb_node;
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struct rb_node *parent = NULL;
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struct pci_io_addr_range *piar;
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/* Walk tree, find a place to insert into tree */
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while (*p) {
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parent = *p;
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piar = rb_entry(parent, struct pci_io_addr_range, rb_node);
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if (alo < piar->addr_lo) {
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p = &parent->rb_left;
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} else if (ahi > piar->addr_hi) {
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p = &parent->rb_right;
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} else {
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if (dev != piar->pcidev ||
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alo != piar->addr_lo || ahi != piar->addr_hi) {
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printk(KERN_WARNING "PIAR: overlapping address range\n");
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}
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return piar;
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}
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}
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piar = (struct pci_io_addr_range *)kmalloc(sizeof(struct pci_io_addr_range), GFP_ATOMIC);
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if (!piar)
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return NULL;
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piar->addr_lo = alo;
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piar->addr_hi = ahi;
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piar->pcidev = dev;
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piar->flags = flags;
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rb_link_node(&piar->rb_node, parent, p);
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rb_insert_color(&piar->rb_node, &pci_io_addr_cache_root.rb_root);
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return piar;
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}
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static void __pci_addr_cache_insert_device(struct pci_dev *dev)
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{
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struct device_node *dn;
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int i;
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int inserted = 0;
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dn = pci_device_to_OF_node(dev);
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if (!dn) {
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printk(KERN_WARNING "PCI: no pci dn found for dev=%s %s\n",
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pci_name(dev), pci_pretty_name(dev));
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return;
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}
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/* Skip any devices for which EEH is not enabled. */
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if (!(dn->eeh_mode & EEH_MODE_SUPPORTED) ||
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dn->eeh_mode & EEH_MODE_NOCHECK) {
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#ifdef DEBUG
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printk(KERN_INFO "PCI: skip building address cache for=%s %s\n",
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pci_name(dev), pci_pretty_name(dev));
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#endif
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return;
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}
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/* The cache holds a reference to the device... */
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pci_dev_get(dev);
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/* Walk resources on this device, poke them into the tree */
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for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
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unsigned long start = pci_resource_start(dev,i);
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unsigned long end = pci_resource_end(dev,i);
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unsigned int flags = pci_resource_flags(dev,i);
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/* We are interested only bus addresses, not dma or other stuff */
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if (0 == (flags & (IORESOURCE_IO | IORESOURCE_MEM)))
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continue;
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if (start == 0 || ~start == 0 || end == 0 || ~end == 0)
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continue;
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pci_addr_cache_insert(dev, start, end, flags);
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inserted = 1;
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}
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/* If there was nothing to add, the cache has no reference... */
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if (!inserted)
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pci_dev_put(dev);
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}
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/**
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* pci_addr_cache_insert_device - Add a device to the address cache
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* @dev: PCI device whose I/O addresses we are interested in.
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*
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* In order to support the fast lookup of devices based on addresses,
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* we maintain a cache of devices that can be quickly searched.
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* This routine adds a device to that cache.
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*/
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void pci_addr_cache_insert_device(struct pci_dev *dev)
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{
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unsigned long flags;
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spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
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__pci_addr_cache_insert_device(dev);
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spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
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}
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static inline void __pci_addr_cache_remove_device(struct pci_dev *dev)
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{
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struct rb_node *n;
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int removed = 0;
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restart:
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n = rb_first(&pci_io_addr_cache_root.rb_root);
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while (n) {
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struct pci_io_addr_range *piar;
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piar = rb_entry(n, struct pci_io_addr_range, rb_node);
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if (piar->pcidev == dev) {
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rb_erase(n, &pci_io_addr_cache_root.rb_root);
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removed = 1;
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kfree(piar);
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goto restart;
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}
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n = rb_next(n);
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}
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/* The cache no longer holds its reference to this device... */
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if (removed)
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pci_dev_put(dev);
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}
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/**
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* pci_addr_cache_remove_device - remove pci device from addr cache
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* @dev: device to remove
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*
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* Remove a device from the addr-cache tree.
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* This is potentially expensive, since it will walk
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* the tree multiple times (once per resource).
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* But so what; device removal doesn't need to be that fast.
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*/
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void pci_addr_cache_remove_device(struct pci_dev *dev)
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{
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unsigned long flags;
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|
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spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
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__pci_addr_cache_remove_device(dev);
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spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
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}
|
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|
|
||
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/**
|
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* pci_addr_cache_build - Build a cache of I/O addresses
|
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*
|
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* Build a cache of pci i/o addresses. This cache will be used to
|
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* find the pci device that corresponds to a given address.
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* This routine scans all pci busses to build the cache.
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* Must be run late in boot process, after the pci controllers
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* have been scaned for devices (after all device resources are known).
|
||
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*/
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void __init pci_addr_cache_build(void)
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||
|
{
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||
|
struct pci_dev *dev = NULL;
|
||
|
|
||
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spin_lock_init(&pci_io_addr_cache_root.piar_lock);
|
||
|
|
||
|
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
|
||
|
/* Ignore PCI bridges ( XXX why ??) */
|
||
|
if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE) {
|
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|
continue;
|
||
|
}
|
||
|
pci_addr_cache_insert_device(dev);
|
||
|
}
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
/* Verify tree built up above, echo back the list of addrs. */
|
||
|
pci_addr_cache_print(&pci_io_addr_cache_root);
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
/* --------------------------------------------------------------- */
|
||
|
/* Above lies the PCI Address Cache. Below lies the EEH event infrastructure */
|
||
|
|
||
|
/**
|
||
|
* eeh_register_notifier - Register to find out about EEH events.
|
||
|
* @nb: notifier block to callback on events
|
||
|
*/
|
||
|
int eeh_register_notifier(struct notifier_block *nb)
|
||
|
{
|
||
|
return notifier_chain_register(&eeh_notifier_chain, nb);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* eeh_unregister_notifier - Unregister to an EEH event notifier.
|
||
|
* @nb: notifier block to callback on events
|
||
|
*/
|
||
|
int eeh_unregister_notifier(struct notifier_block *nb)
|
||
|
{
|
||
|
return notifier_chain_unregister(&eeh_notifier_chain, nb);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* 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 device_node *dn, int rets[])
|
||
|
{
|
||
|
int token, outputs;
|
||
|
|
||
|
if (ibm_read_slot_reset_state2 != RTAS_UNKNOWN_SERVICE) {
|
||
|
token = ibm_read_slot_reset_state2;
|
||
|
outputs = 4;
|
||
|
} else {
|
||
|
token = ibm_read_slot_reset_state;
|
||
|
outputs = 3;
|
||
|
}
|
||
|
|
||
|
return rtas_call(token, 3, outputs, rets, dn->eeh_config_addr,
|
||
|
BUID_HI(dn->phb->buid), BUID_LO(dn->phb->buid));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* eeh_panic - call panic() for an eeh event that cannot be handled.
|
||
|
* The philosophy of this routine is that it is better to panic and
|
||
|
* halt the OS than it is to risk possible data corruption by
|
||
|
* oblivious device drivers that don't know better.
|
||
|
*
|
||
|
* @dev pci device that had an eeh event
|
||
|
* @reset_state current reset state of the device slot
|
||
|
*/
|
||
|
static void eeh_panic(struct pci_dev *dev, int reset_state)
|
||
|
{
|
||
|
/*
|
||
|
* XXX We should create a separate sysctl for this.
|
||
|
*
|
||
|
* Since the panic_on_oops sysctl is used to halt the system
|
||
|
* in light of potential corruption, we can use it here.
|
||
|
*/
|
||
|
if (panic_on_oops)
|
||
|
panic("EEH: MMIO failure (%d) on device:%s %s\n", reset_state,
|
||
|
pci_name(dev), pci_pretty_name(dev));
|
||
|
else {
|
||
|
__get_cpu_var(ignored_failures)++;
|
||
|
printk(KERN_INFO "EEH: Ignored MMIO failure (%d) on device:%s %s\n",
|
||
|
reset_state, pci_name(dev), pci_pretty_name(dev));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* eeh_event_handler - dispatch EEH events. The detection of a frozen
|
||
|
* slot can occur inside an interrupt, where it can be hard to do
|
||
|
* anything about it. The goal of this routine is to pull these
|
||
|
* detection events out of the context of the interrupt handler, and
|
||
|
* re-dispatch them for processing at a later time in a normal context.
|
||
|
*
|
||
|
* @dummy - unused
|
||
|
*/
|
||
|
static void eeh_event_handler(void *dummy)
|
||
|
{
|
||
|
unsigned long flags;
|
||
|
struct eeh_event *event;
|
||
|
|
||
|
while (1) {
|
||
|
spin_lock_irqsave(&eeh_eventlist_lock, flags);
|
||
|
event = NULL;
|
||
|
if (!list_empty(&eeh_eventlist)) {
|
||
|
event = list_entry(eeh_eventlist.next, struct eeh_event, list);
|
||
|
list_del(&event->list);
|
||
|
}
|
||
|
spin_unlock_irqrestore(&eeh_eventlist_lock, flags);
|
||
|
if (event == NULL)
|
||
|
break;
|
||
|
|
||
|
printk(KERN_INFO "EEH: MMIO failure (%d), notifiying device "
|
||
|
"%s %s\n", event->reset_state,
|
||
|
pci_name(event->dev), pci_pretty_name(event->dev));
|
||
|
|
||
|
atomic_set(&eeh_fail_count, 0);
|
||
|
notifier_call_chain (&eeh_notifier_chain,
|
||
|
EEH_NOTIFY_FREEZE, event);
|
||
|
|
||
|
__get_cpu_var(slot_resets)++;
|
||
|
|
||
|
pci_dev_put(event->dev);
|
||
|
kfree(event);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* eeh_token_to_phys - convert EEH address token to phys address
|
||
|
* @token i/o token, should be address in the form 0xE....
|
||
|
*/
|
||
|
static inline unsigned long eeh_token_to_phys(unsigned long token)
|
||
|
{
|
||
|
pte_t *ptep;
|
||
|
unsigned long pa;
|
||
|
|
||
|
ptep = find_linux_pte(ioremap_mm.pgd, token);
|
||
|
if (!ptep)
|
||
|
return token;
|
||
|
pa = pte_pfn(*ptep) << PAGE_SHIFT;
|
||
|
|
||
|
return pa | (token & (PAGE_SIZE-1));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* 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 solt 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;
|
||
|
int rc, reset_state;
|
||
|
struct eeh_event *event;
|
||
|
|
||
|
__get_cpu_var(total_mmio_ffs)++;
|
||
|
|
||
|
if (!eeh_subsystem_enabled)
|
||
|
return 0;
|
||
|
|
||
|
if (!dn)
|
||
|
return 0;
|
||
|
|
||
|
/* Access to IO BARs might get this far and still not want checking. */
|
||
|
if (!(dn->eeh_mode & EEH_MODE_SUPPORTED) ||
|
||
|
dn->eeh_mode & EEH_MODE_NOCHECK) {
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
if (!dn->eeh_config_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...
|
||
|
*/
|
||
|
if (dn->eeh_mode & EEH_MODE_ISOLATED) {
|
||
|
atomic_inc(&eeh_fail_count);
|
||
|
if (atomic_read(&eeh_fail_count) >= EEH_MAX_FAILS) {
|
||
|
/* re-read the slot reset state */
|
||
|
if (read_slot_reset_state(dn, rets) != 0)
|
||
|
rets[0] = -1; /* reset state unknown */
|
||
|
eeh_panic(dev, rets[0]);
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* 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(dn, rets);
|
||
|
if (!(ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4))) {
|
||
|
__get_cpu_var(false_positives)++;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/* prevent repeated reports of this failure */
|
||
|
dn->eeh_mode |= EEH_MODE_ISOLATED;
|
||
|
|
||
|
reset_state = rets[0];
|
||
|
|
||
|
spin_lock_irqsave(&slot_errbuf_lock, flags);
|
||
|
memset(slot_errbuf, 0, eeh_error_buf_size);
|
||
|
|
||
|
rc = rtas_call(ibm_slot_error_detail,
|
||
|
8, 1, NULL, dn->eeh_config_addr,
|
||
|
BUID_HI(dn->phb->buid),
|
||
|
BUID_LO(dn->phb->buid), NULL, 0,
|
||
|
virt_to_phys(slot_errbuf),
|
||
|
eeh_error_buf_size,
|
||
|
1 /* Temporary Error */);
|
||
|
|
||
|
if (rc == 0)
|
||
|
log_error(slot_errbuf, ERR_TYPE_RTAS_LOG, 0);
|
||
|
spin_unlock_irqrestore(&slot_errbuf_lock, flags);
|
||
|
|
||
|
printk(KERN_INFO "EEH: MMIO failure (%d) on device: %s %s\n",
|
||
|
rets[0], dn->name, dn->full_name);
|
||
|
event = kmalloc(sizeof(*event), GFP_ATOMIC);
|
||
|
if (event == NULL) {
|
||
|
eeh_panic(dev, reset_state);
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
event->dev = dev;
|
||
|
event->dn = dn;
|
||
|
event->reset_state = reset_state;
|
||
|
|
||
|
/* We may or may not be called in an interrupt context */
|
||
|
spin_lock_irqsave(&eeh_eventlist_lock, flags);
|
||
|
list_add(&event->list, &eeh_eventlist);
|
||
|
spin_unlock_irqrestore(&eeh_eventlist_lock, flags);
|
||
|
|
||
|
/* 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();
|
||
|
schedule_work(&eeh_event_wq);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(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.
|
||
|
* 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)
|
||
|
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);
|
||
|
|
||
|
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;
|
||
|
|
||
|
dn->eeh_mode = 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")) {
|
||
|
dn->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 ((*class_code >> 16) == PCI_BASE_CLASS_DISPLAY)
|
||
|
enable = 0;
|
||
|
|
||
|
if (!enable)
|
||
|
dn->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;
|
||
|
dn->eeh_mode |= EEH_MODE_SUPPORTED;
|
||
|
dn->eeh_config_addr = regs[0];
|
||
|
#ifdef DEBUG
|
||
|
printk(KERN_DEBUG "EEH: %s: eeh enabled\n", dn->full_name);
|
||
|
#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 && (dn->parent->eeh_mode & EEH_MODE_SUPPORTED)) {
|
||
|
/* Parent supports EEH. */
|
||
|
dn->eeh_mode |= EEH_MODE_SUPPORTED;
|
||
|
dn->eeh_config_addr = 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;
|
||
|
|
||
|
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");
|
||
|
|
||
|
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)
|
||
|
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)
|
||
|
return;
|
||
|
phb = dn->phb;
|
||
|
if (NULL == phb || 0 == phb->buid) {
|
||
|
printk(KERN_WARNING "EEH: Expected buid but found none\n");
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
info.buid_hi = BUID_HI(phb->buid);
|
||
|
info.buid_lo = BUID_LO(phb->buid);
|
||
|
early_enable_eeh(dn, &info);
|
||
|
}
|
||
|
EXPORT_SYMBOL(eeh_add_device_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)
|
||
|
{
|
||
|
if (!dev || !eeh_subsystem_enabled)
|
||
|
return;
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
printk(KERN_DEBUG "EEH: adding device %s %s\n", pci_name(dev),
|
||
|
pci_pretty_name(dev));
|
||
|
#endif
|
||
|
|
||
|
pci_addr_cache_insert_device (dev);
|
||
|
}
|
||
|
EXPORT_SYMBOL(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)
|
||
|
{
|
||
|
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 %s\n", pci_name(dev),
|
||
|
pci_pretty_name(dev));
|
||
|
#endif
|
||
|
pci_addr_cache_remove_device(dev);
|
||
|
}
|
||
|
EXPORT_SYMBOL(eeh_remove_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;
|
||
|
|
||
|
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);
|
||
|
}
|
||
|
|
||
|
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, "eeh_total_mmio_ffs=%ld\n"
|
||
|
"eeh_false_positives=%ld\n"
|
||
|
"eeh_ignored_failures=%ld\n"
|
||
|
"eeh_slot_resets=%ld\n"
|
||
|
"eeh_fail_count=%d\n",
|
||
|
ffs, positives, failures, resets,
|
||
|
eeh_fail_count.counter);
|
||
|
}
|
||
|
|
||
|
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 (systemcfg->platform & PLATFORM_PSERIES) {
|
||
|
e = create_proc_entry("ppc64/eeh", 0, NULL);
|
||
|
if (e)
|
||
|
e->proc_fops = &proc_eeh_operations;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
__initcall(eeh_init_proc);
|