kernel-ark/arch/sparc64/kernel/pci_common.c

826 lines
21 KiB
C
Raw Normal View History

/* $Id: pci_common.c,v 1.29 2002/02/01 00:56:03 davem Exp $
* pci_common.c: PCI controller common support.
*
* Copyright (C) 1999 David S. Miller (davem@redhat.com)
*/
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <asm/pbm.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#include "pci_impl.h"
/* Fix self device of BUS and hook it into BUS->self.
* The pci_scan_bus does not do this for the host bridge.
*/
void __init pci_fixup_host_bridge_self(struct pci_bus *pbus)
{
struct pci_dev *pdev;
list_for_each_entry(pdev, &pbus->devices, bus_list) {
if (pdev->class >> 8 == PCI_CLASS_BRIDGE_HOST) {
pbus->self = pdev;
return;
}
}
prom_printf("PCI: Critical error, cannot find host bridge PDEV.\n");
prom_halt();
}
/* Find the OBP PROM device tree node for a PCI device. */
static struct device_node * __init
find_device_prom_node(struct pci_pbm_info *pbm, struct pci_dev *pdev,
struct device_node *bus_node,
struct linux_prom_pci_registers **pregs,
int *nregs)
{
struct device_node *dp;
*nregs = 0;
/*
* Return the PBM's PROM node in case we are it's PCI device,
* as the PBM's reg property is different to standard PCI reg
* properties. We would delete this device entry otherwise,
* which confuses XFree86's device probing...
*/
if ((pdev->bus->number == pbm->pci_bus->number) && (pdev->devfn == 0) &&
(pdev->vendor == PCI_VENDOR_ID_SUN) &&
(pdev->device == PCI_DEVICE_ID_SUN_PBM ||
pdev->device == PCI_DEVICE_ID_SUN_SCHIZO ||
pdev->device == PCI_DEVICE_ID_SUN_TOMATILLO ||
pdev->device == PCI_DEVICE_ID_SUN_SABRE ||
pdev->device == PCI_DEVICE_ID_SUN_HUMMINGBIRD))
return bus_node;
dp = bus_node->child;
while (dp) {
struct linux_prom_pci_registers *regs;
struct property *prop;
int len;
prop = of_find_property(dp, "reg", &len);
if (!prop)
goto do_next_sibling;
regs = prop->value;
if (((regs[0].phys_hi >> 8) & 0xff) == pdev->devfn) {
*pregs = regs;
*nregs = len / sizeof(struct linux_prom_pci_registers);
return dp;
}
do_next_sibling:
dp = dp->sibling;
}
return NULL;
}
/* Older versions of OBP on PCI systems encode 64-bit MEM
* space assignments incorrectly, this fixes them up. We also
* take the opportunity here to hide other kinds of bogus
* assignments.
*/
static void __init fixup_obp_assignments(struct pci_dev *pdev,
struct pcidev_cookie *pcp)
{
int i;
if (pdev->vendor == PCI_VENDOR_ID_AL &&
(pdev->device == PCI_DEVICE_ID_AL_M7101 ||
pdev->device == PCI_DEVICE_ID_AL_M1533)) {
int i;
/* Zap all of the normal resources, they are
* meaningless and generate bogus resource collision
* messages. This is OpenBoot's ill-fated attempt to
* represent the implicit resources that these devices
* have.
*/
pcp->num_prom_assignments = 0;
for (i = 0; i < 6; i++) {
pdev->resource[i].start =
pdev->resource[i].end =
pdev->resource[i].flags = 0;
}
pdev->resource[PCI_ROM_RESOURCE].start =
pdev->resource[PCI_ROM_RESOURCE].end =
pdev->resource[PCI_ROM_RESOURCE].flags = 0;
return;
}
for (i = 0; i < pcp->num_prom_assignments; i++) {
struct linux_prom_pci_registers *ap;
int space;
ap = &pcp->prom_assignments[i];
space = ap->phys_hi >> 24;
if ((space & 0x3) == 2 &&
(space & 0x4) != 0) {
ap->phys_hi &= ~(0x7 << 24);
ap->phys_hi |= 0x3 << 24;
}
}
}
/* Fill in the PCI device cookie sysdata for the given
* PCI device. This cookie is the means by which one
* can get to OBP and PCI controller specific information
* for a PCI device.
*/
static void __init pdev_cookie_fillin(struct pci_pbm_info *pbm,
struct pci_dev *pdev,
struct device_node *bus_node)
{
struct linux_prom_pci_registers *pregs = NULL;
struct pcidev_cookie *pcp;
struct device_node *dp;
struct property *prop;
int nregs, len;
dp = find_device_prom_node(pbm, pdev, bus_node,
&pregs, &nregs);
if (!dp) {
/* If it is not in the OBP device tree then
* there must be a damn good reason for it.
*
* So what we do is delete the device from the
* PCI device tree completely. This scenario
* is seen, for example, on CP1500 for the
* second EBUS/HappyMeal pair if the external
* connector for it is not present.
*/
pci_remove_bus_device(pdev);
return;
}
pcp = kzalloc(sizeof(*pcp), GFP_ATOMIC);
if (pcp == NULL) {
prom_printf("PCI_COOKIE: Fatal malloc error, aborting...\n");
prom_halt();
}
pcp->pbm = pbm;
pcp->prom_node = dp;
pcp->op = of_find_device_by_node(dp);
memcpy(pcp->prom_regs, pregs,
nregs * sizeof(struct linux_prom_pci_registers));
pcp->num_prom_regs = nregs;
/* We can't have the pcidev_cookie assignments be just
* direct pointers into the property value, since they
* are potentially modified by the probing process.
*/
prop = of_find_property(dp, "assigned-addresses", &len);
if (!prop) {
pcp->num_prom_assignments = 0;
} else {
memcpy(pcp->prom_assignments, prop->value, len);
pcp->num_prom_assignments =
(len / sizeof(pcp->prom_assignments[0]));
}
if (strcmp(dp->name, "ebus") == 0) {
struct linux_prom_ebus_ranges *erng;
int iter;
/* EBUS is special... */
prop = of_find_property(dp, "ranges", &len);
if (!prop) {
prom_printf("EBUS: Fatal error, no range property\n");
prom_halt();
}
erng = prop->value;
len = (len / sizeof(erng[0]));
for (iter = 0; iter < len; iter++) {
struct linux_prom_ebus_ranges *ep = &erng[iter];
struct linux_prom_pci_registers *ap;
ap = &pcp->prom_assignments[iter];
ap->phys_hi = ep->parent_phys_hi;
ap->phys_mid = ep->parent_phys_mid;
ap->phys_lo = ep->parent_phys_lo;
ap->size_hi = 0;
ap->size_lo = ep->size;
}
pcp->num_prom_assignments = len;
}
fixup_obp_assignments(pdev, pcp);
pdev->sysdata = pcp;
}
void __init pci_fill_in_pbm_cookies(struct pci_bus *pbus,
struct pci_pbm_info *pbm,
struct device_node *dp)
{
struct pci_dev *pdev, *pdev_next;
struct pci_bus *this_pbus, *pbus_next;
/* This must be _safe because the cookie fillin
routine can delete devices from the tree. */
list_for_each_entry_safe(pdev, pdev_next, &pbus->devices, bus_list)
pdev_cookie_fillin(pbm, pdev, dp);
list_for_each_entry_safe(this_pbus, pbus_next, &pbus->children, node) {
struct pcidev_cookie *pcp = this_pbus->self->sysdata;
pci_fill_in_pbm_cookies(this_pbus, pbm, pcp->prom_node);
}
}
static void __init bad_assignment(struct pci_dev *pdev,
struct linux_prom_pci_registers *ap,
struct resource *res,
int do_prom_halt)
{
prom_printf("PCI: Bogus PROM assignment. BUS[%02x] DEVFN[%x]\n",
pdev->bus->number, pdev->devfn);
if (ap)
prom_printf("PCI: phys[%08x:%08x:%08x] size[%08x:%08x]\n",
ap->phys_hi, ap->phys_mid, ap->phys_lo,
ap->size_hi, ap->size_lo);
if (res)
prom_printf("PCI: RES[%016lx-->%016lx:(%lx)]\n",
res->start, res->end, res->flags);
if (do_prom_halt)
prom_halt();
}
static struct resource *
__init get_root_resource(struct linux_prom_pci_registers *ap,
struct pci_pbm_info *pbm)
{
int space = (ap->phys_hi >> 24) & 3;
switch (space) {
case 0:
/* Configuration space, silently ignore it. */
return NULL;
case 1:
/* 16-bit IO space */
return &pbm->io_space;
case 2:
/* 32-bit MEM space */
return &pbm->mem_space;
case 3:
/* 64-bit MEM space, these are allocated out of
* the 32-bit mem_space range for the PBM, ie.
* we just zero out the upper 32-bits.
*/
return &pbm->mem_space;
default:
printk("PCI: What is resource space %x?\n", space);
return NULL;
};
}
static struct resource *
__init get_device_resource(struct linux_prom_pci_registers *ap,
struct pci_dev *pdev)
{
struct resource *res;
int breg = (ap->phys_hi & 0xff);
switch (breg) {
case PCI_ROM_ADDRESS:
/* Unfortunately I have seen several cases where
* buggy FCODE uses a space value of '1' (I/O space)
* in the register property for the ROM address
* so disable this sanity check for now.
*/
#if 0
{
int space = (ap->phys_hi >> 24) & 3;
/* It had better be MEM space. */
if (space != 2)
bad_assignment(pdev, ap, NULL, 0);
}
#endif
res = &pdev->resource[PCI_ROM_RESOURCE];
break;
case PCI_BASE_ADDRESS_0:
case PCI_BASE_ADDRESS_1:
case PCI_BASE_ADDRESS_2:
case PCI_BASE_ADDRESS_3:
case PCI_BASE_ADDRESS_4:
case PCI_BASE_ADDRESS_5:
res = &pdev->resource[(breg - PCI_BASE_ADDRESS_0) / 4];
break;
default:
bad_assignment(pdev, ap, NULL, 0);
res = NULL;
break;
};
return res;
}
static int __init pdev_resource_collisions_expected(struct pci_dev *pdev)
{
if (pdev->vendor != PCI_VENDOR_ID_SUN)
return 0;
if (pdev->device == PCI_DEVICE_ID_SUN_RIO_EBUS ||
pdev->device == PCI_DEVICE_ID_SUN_RIO_1394 ||
pdev->device == PCI_DEVICE_ID_SUN_RIO_USB)
return 1;
return 0;
}
static void __init pdev_record_assignments(struct pci_pbm_info *pbm,
struct pci_dev *pdev)
{
struct pcidev_cookie *pcp = pdev->sysdata;
int i;
for (i = 0; i < pcp->num_prom_assignments; i++) {
struct linux_prom_pci_registers *ap;
struct resource *root, *res;
/* The format of this property is specified in
* the PCI Bus Binding to IEEE1275-1994.
*/
ap = &pcp->prom_assignments[i];
root = get_root_resource(ap, pbm);
res = get_device_resource(ap, pdev);
if (root == NULL || res == NULL ||
res->flags == 0)
continue;
/* Ok we know which resource this PROM assignment is
* for, sanity check it.
*/
if ((res->start & 0xffffffffUL) != ap->phys_lo)
bad_assignment(pdev, ap, res, 1);
/* If it is a 64-bit MEM space assignment, verify that
* the resource is too and that the upper 32-bits match.
*/
if (((ap->phys_hi >> 24) & 3) == 3) {
if (((res->flags & IORESOURCE_MEM) == 0) ||
((res->flags & PCI_BASE_ADDRESS_MEM_TYPE_MASK)
!= PCI_BASE_ADDRESS_MEM_TYPE_64))
bad_assignment(pdev, ap, res, 1);
if ((res->start >> 32) != ap->phys_mid)
bad_assignment(pdev, ap, res, 1);
/* PBM cannot generate cpu initiated PIOs
* to the full 64-bit space. Therefore the
* upper 32-bits better be zero. If it is
* not, just skip it and we will assign it
* properly ourselves.
*/
if ((res->start >> 32) != 0UL) {
printk(KERN_ERR "PCI: OBP assigns out of range MEM address "
"%016lx for region %ld on device %s\n",
res->start, (res - &pdev->resource[0]), pci_name(pdev));
continue;
}
}
/* Adjust the resource into the physical address space
* of this PBM.
*/
pbm->parent->resource_adjust(pdev, res, root);
if (request_resource(root, res) < 0) {
/* OK, there is some conflict. But this is fine
* since we'll reassign it in the fixup pass.
*
* We notify the user that OBP made an error if it
* is a case we don't expect.
*/
if (!pdev_resource_collisions_expected(pdev)) {
printk(KERN_ERR "PCI: Address space collision on region %ld "
"[%016lx:%016lx] of device %s\n",
(res - &pdev->resource[0]),
res->start, res->end,
pci_name(pdev));
}
}
}
}
void __init pci_record_assignments(struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *dev;
struct pci_bus *bus;
list_for_each_entry(dev, &pbus->devices, bus_list)
pdev_record_assignments(pbm, dev);
list_for_each_entry(bus, &pbus->children, node)
pci_record_assignments(pbm, bus);
}
/* Return non-zero if PDEV has implicit I/O resources even
* though it may not have an I/O base address register
* active.
*/
static int __init has_implicit_io(struct pci_dev *pdev)
{
int class = pdev->class >> 8;
if (class == PCI_CLASS_NOT_DEFINED ||
class == PCI_CLASS_NOT_DEFINED_VGA ||
class == PCI_CLASS_STORAGE_IDE ||
(pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
return 1;
return 0;
}
static void __init pdev_assign_unassigned(struct pci_pbm_info *pbm,
struct pci_dev *pdev)
{
u32 reg;
u16 cmd;
int i, io_seen, mem_seen;
io_seen = mem_seen = 0;
for (i = 0; i < PCI_NUM_RESOURCES; i++) {
struct resource *root, *res;
unsigned long size, min, max, align;
res = &pdev->resource[i];
if (res->flags & IORESOURCE_IO)
io_seen++;
else if (res->flags & IORESOURCE_MEM)
mem_seen++;
/* If it is already assigned or the resource does
* not exist, there is nothing to do.
*/
if (res->parent != NULL || res->flags == 0UL)
continue;
/* Determine the root we allocate from. */
if (res->flags & IORESOURCE_IO) {
root = &pbm->io_space;
min = root->start + 0x400UL;
max = root->end;
} else {
root = &pbm->mem_space;
min = root->start;
max = min + 0x80000000UL;
}
size = res->end - res->start;
align = size + 1;
if (allocate_resource(root, res, size + 1, min, max, align, NULL, NULL) < 0) {
/* uh oh */
prom_printf("PCI: Failed to allocate resource %d for %s\n",
i, pci_name(pdev));
prom_halt();
}
/* Update PCI config space. */
pbm->parent->base_address_update(pdev, i);
}
/* Special case, disable the ROM. Several devices
* act funny (ie. do not respond to memory space writes)
* when it is left enabled. A good example are Qlogic,ISP
* adapters.
*/
pci_read_config_dword(pdev, PCI_ROM_ADDRESS, &reg);
reg &= ~PCI_ROM_ADDRESS_ENABLE;
pci_write_config_dword(pdev, PCI_ROM_ADDRESS, reg);
/* If we saw I/O or MEM resources, enable appropriate
* bits in PCI command register.
*/
if (io_seen || mem_seen) {
pci_read_config_word(pdev, PCI_COMMAND, &cmd);
if (io_seen || has_implicit_io(pdev))
cmd |= PCI_COMMAND_IO;
if (mem_seen)
cmd |= PCI_COMMAND_MEMORY;
pci_write_config_word(pdev, PCI_COMMAND, cmd);
}
/* If this is a PCI bridge or an IDE controller,
* enable bus mastering. In the former case also
* set the cache line size correctly.
*/
if (((pdev->class >> 8) == PCI_CLASS_BRIDGE_PCI) ||
(((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) &&
((pdev->class & 0x80) != 0))) {
pci_read_config_word(pdev, PCI_COMMAND, &cmd);
cmd |= PCI_COMMAND_MASTER;
pci_write_config_word(pdev, PCI_COMMAND, cmd);
if ((pdev->class >> 8) == PCI_CLASS_BRIDGE_PCI)
pci_write_config_byte(pdev,
PCI_CACHE_LINE_SIZE,
(64 / sizeof(u32)));
}
}
void __init pci_assign_unassigned(struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *dev;
struct pci_bus *bus;
list_for_each_entry(dev, &pbus->devices, bus_list)
pdev_assign_unassigned(pbm, dev);
list_for_each_entry(bus, &pbus->children, node)
pci_assign_unassigned(pbm, bus);
}
static void __init pdev_fixup_irq(struct pci_dev *pdev)
{
struct pcidev_cookie *pcp = pdev->sysdata;
struct of_device *op = pcp->op;
if (op->irqs[0] == 0xffffffff) {
pdev->irq = PCI_IRQ_NONE;
return;
}
pdev->irq = op->irqs[0];
pci_write_config_byte(pdev, PCI_INTERRUPT_LINE,
pdev->irq & PCI_IRQ_INO);
}
void __init pci_fixup_irq(struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *dev;
struct pci_bus *bus;
list_for_each_entry(dev, &pbus->devices, bus_list)
pdev_fixup_irq(dev);
list_for_each_entry(bus, &pbus->children, node)
pci_fixup_irq(pbm, bus);
}
static void pdev_setup_busmastering(struct pci_dev *pdev, int is_66mhz)
{
u16 cmd;
u8 hdr_type, min_gnt, ltimer;
pci_read_config_word(pdev, PCI_COMMAND, &cmd);
cmd |= PCI_COMMAND_MASTER;
pci_write_config_word(pdev, PCI_COMMAND, cmd);
/* Read it back, if the mastering bit did not
* get set, the device does not support bus
* mastering so we have nothing to do here.
*/
pci_read_config_word(pdev, PCI_COMMAND, &cmd);
if ((cmd & PCI_COMMAND_MASTER) == 0)
return;
/* Set correct cache line size, 64-byte on all
* Sparc64 PCI systems. Note that the value is
* measured in 32-bit words.
*/
pci_write_config_byte(pdev, PCI_CACHE_LINE_SIZE,
64 / sizeof(u32));
pci_read_config_byte(pdev, PCI_HEADER_TYPE, &hdr_type);
hdr_type &= ~0x80;
if (hdr_type != PCI_HEADER_TYPE_NORMAL)
return;
/* If the latency timer is already programmed with a non-zero
* value, assume whoever set it (OBP or whoever) knows what
* they are doing.
*/
pci_read_config_byte(pdev, PCI_LATENCY_TIMER, &ltimer);
if (ltimer != 0)
return;
/* XXX Since I'm tipping off the min grant value to
* XXX choose a suitable latency timer value, I also
* XXX considered making use of the max latency value
* XXX as well. Unfortunately I've seen too many bogusly
* XXX low settings for it to the point where it lacks
* XXX any usefulness. In one case, an ethernet card
* XXX claimed a min grant of 10 and a max latency of 5.
* XXX Now, if I had two such cards on the same bus I
* XXX could not set the desired burst period (calculated
* XXX from min grant) without violating the max latency
* XXX bound. Duh...
* XXX
* XXX I blame dumb PC bios implementors for stuff like
* XXX this, most of them don't even try to do something
* XXX sensible with latency timer values and just set some
* XXX default value (usually 32) into every device.
*/
pci_read_config_byte(pdev, PCI_MIN_GNT, &min_gnt);
if (min_gnt == 0) {
/* If no min_gnt setting then use a default
* value.
*/
if (is_66mhz)
ltimer = 16;
else
ltimer = 32;
} else {
int shift_factor;
if (is_66mhz)
shift_factor = 2;
else
shift_factor = 3;
/* Use a default value when the min_gnt value
* is erroneously high.
*/
if (((unsigned int) min_gnt << shift_factor) > 512 ||
((min_gnt << shift_factor) & 0xff) == 0) {
ltimer = 8 << shift_factor;
} else {
ltimer = min_gnt << shift_factor;
}
}
pci_write_config_byte(pdev, PCI_LATENCY_TIMER, ltimer);
}
void pci_determine_66mhz_disposition(struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *pdev;
int all_are_66mhz;
u16 status;
if (pbm->is_66mhz_capable == 0) {
all_are_66mhz = 0;
goto out;
}
all_are_66mhz = 1;
list_for_each_entry(pdev, &pbus->devices, bus_list) {
pci_read_config_word(pdev, PCI_STATUS, &status);
if (!(status & PCI_STATUS_66MHZ)) {
all_are_66mhz = 0;
break;
}
}
out:
pbm->all_devs_66mhz = all_are_66mhz;
printk("PCI%d(PBM%c): Bus running at %dMHz\n",
pbm->parent->index,
(pbm == &pbm->parent->pbm_A) ? 'A' : 'B',
(all_are_66mhz ? 66 : 33));
}
void pci_setup_busmastering(struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *dev;
struct pci_bus *bus;
int is_66mhz;
is_66mhz = pbm->is_66mhz_capable && pbm->all_devs_66mhz;
list_for_each_entry(dev, &pbus->devices, bus_list)
pdev_setup_busmastering(dev, is_66mhz);
list_for_each_entry(bus, &pbus->children, node)
pci_setup_busmastering(pbm, bus);
}
void pci_register_legacy_regions(struct resource *io_res,
struct resource *mem_res)
{
struct resource *p;
/* VGA Video RAM. */
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return;
p->name = "Video RAM area";
p->start = mem_res->start + 0xa0000UL;
p->end = p->start + 0x1ffffUL;
p->flags = IORESOURCE_BUSY;
request_resource(mem_res, p);
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return;
p->name = "System ROM";
p->start = mem_res->start + 0xf0000UL;
p->end = p->start + 0xffffUL;
p->flags = IORESOURCE_BUSY;
request_resource(mem_res, p);
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return;
p->name = "Video ROM";
p->start = mem_res->start + 0xc0000UL;
p->end = p->start + 0x7fffUL;
p->flags = IORESOURCE_BUSY;
request_resource(mem_res, p);
}
/* Generic helper routines for PCI error reporting. */
void pci_scan_for_target_abort(struct pci_controller_info *p,
struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *pdev;
struct pci_bus *bus;
list_for_each_entry(pdev, &pbus->devices, bus_list) {
u16 status, error_bits;
pci_read_config_word(pdev, PCI_STATUS, &status);
error_bits =
(status & (PCI_STATUS_SIG_TARGET_ABORT |
PCI_STATUS_REC_TARGET_ABORT));
if (error_bits) {
pci_write_config_word(pdev, PCI_STATUS, error_bits);
printk("PCI%d(PBM%c): Device [%s] saw Target Abort [%016x]\n",
p->index, ((pbm == &p->pbm_A) ? 'A' : 'B'),
pci_name(pdev), status);
}
}
list_for_each_entry(bus, &pbus->children, node)
pci_scan_for_target_abort(p, pbm, bus);
}
void pci_scan_for_master_abort(struct pci_controller_info *p,
struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *pdev;
struct pci_bus *bus;
list_for_each_entry(pdev, &pbus->devices, bus_list) {
u16 status, error_bits;
pci_read_config_word(pdev, PCI_STATUS, &status);
error_bits =
(status & (PCI_STATUS_REC_MASTER_ABORT));
if (error_bits) {
pci_write_config_word(pdev, PCI_STATUS, error_bits);
printk("PCI%d(PBM%c): Device [%s] received Master Abort [%016x]\n",
p->index, ((pbm == &p->pbm_A) ? 'A' : 'B'),
pci_name(pdev), status);
}
}
list_for_each_entry(bus, &pbus->children, node)
pci_scan_for_master_abort(p, pbm, bus);
}
void pci_scan_for_parity_error(struct pci_controller_info *p,
struct pci_pbm_info *pbm,
struct pci_bus *pbus)
{
struct pci_dev *pdev;
struct pci_bus *bus;
list_for_each_entry(pdev, &pbus->devices, bus_list) {
u16 status, error_bits;
pci_read_config_word(pdev, PCI_STATUS, &status);
error_bits =
(status & (PCI_STATUS_PARITY |
PCI_STATUS_DETECTED_PARITY));
if (error_bits) {
pci_write_config_word(pdev, PCI_STATUS, error_bits);
printk("PCI%d(PBM%c): Device [%s] saw Parity Error [%016x]\n",
p->index, ((pbm == &p->pbm_A) ? 'A' : 'B'),
pci_name(pdev), status);
}
}
list_for_each_entry(bus, &pbus->children, node)
pci_scan_for_parity_error(p, pbm, bus);
}