freebsd-dev/sys/i386/pci/pci_cfgreg.c
Peter Wemm af3d516f55 Initiate de-orbit burn for USE_PCI_BIOS_FOR_READ_WRITE. This has been
#if'ed out for a while.  Complete the deed and tidy up some other bits.

We need to be able to call this stuff from outer edges of interrupt
handlers for devices that have the ISR bits in pci config space.  Making
the bios code mpsafe was just too hairy.  We had also stubbed it out some
time ago due to there simply being too much brokenness in too many systems.
This adds a leaf lock so that it is safe to use pci_read_config() and
pci_write_config() from interrupt handlers.  We still will use pcibios
to do interrupt routing if there is no acpi.. [yes, I tested this]

Briefly glanced at by:  imp
2003-02-18 03:36:49 +00:00

823 lines
20 KiB
C

/*
* Copyright (c) 1997, Stefan Esser <se@freebsd.org>
* Copyright (c) 2000, Michael Smith <msmith@freebsd.org>
* Copyright (c) 2000, BSDi
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*
*/
#include <sys/param.h> /* XXX trim includes */
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <machine/md_var.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <isa/isavar.h>
#include <machine/pci_cfgreg.h>
#include <machine/segments.h>
#include <machine/pc/bios.h>
#ifdef APIC_IO
#include <machine/smp.h>
#endif /* APIC_IO */
#include "pcib_if.h"
#define PRVERB(a) do { \
if (bootverbose) \
printf a ; \
} while(0)
static int cfgmech;
static int devmax;
static int pci_cfgintr_valid(struct PIR_entry *pe, int pin, int irq);
static int pci_cfgintr_unique(struct PIR_entry *pe, int pin);
static int pci_cfgintr_linked(struct PIR_entry *pe, int pin);
static int pci_cfgintr_search(struct PIR_entry *pe, int bus, int device, int matchpin, int pin);
static int pci_cfgintr_virgin(struct PIR_entry *pe, int pin);
static void pci_print_irqmask(u_int16_t irqs);
static void pci_print_route_table(struct PIR_table *prt, int size);
static int pcireg_cfgread(int bus, int slot, int func, int reg, int bytes);
static void pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes);
static int pcireg_cfgopen(void);
static struct PIR_table *pci_route_table;
static int pci_route_count;
static struct mtx pcicfg_mtx;
/*
* Some BIOS writers seem to want to ignore the spec and put
* 0 in the intline rather than 255 to indicate none. Some use
* numbers in the range 128-254 to indicate something strange and
* apparently undocumented anywhere. Assume these are completely bogus
* and map them to 255, which means "none".
*/
static __inline__ int
pci_i386_map_intline(int line)
{
if (line == 0 || line >= 128)
return (PCI_INVALID_IRQ);
return (line);
}
static u_int16_t
pcibios_get_version(void)
{
struct bios_regs args;
if (PCIbios.ventry == 0) {
PRVERB(("pcibios: No call entry point\n"));
return (0);
}
args.eax = PCIBIOS_BIOS_PRESENT;
if (bios32(&args, PCIbios.ventry, GSEL(GCODE_SEL, SEL_KPL))) {
PRVERB(("pcibios: BIOS_PRESENT call failed\n"));
return (0);
}
if (args.edx != 0x20494350) {
PRVERB(("pcibios: BIOS_PRESENT didn't return 'PCI ' in edx\n"));
return (0);
}
return (args.ebx & 0xffff);
}
/*
* Initialise access to PCI configuration space
*/
int
pci_cfgregopen(void)
{
static int opened = 0;
u_long sigaddr;
static struct PIR_table *pt;
u_int16_t v;
u_int8_t ck, *cv;
int i;
if (opened)
return(1);
if (pcireg_cfgopen() == 0)
return(0);
v = pcibios_get_version();
if (v > 0)
printf("pcibios: BIOS version %x.%02x\n", (v & 0xff00) >> 8,
v & 0xff);
/*
* Look for the interrupt routing table.
*
* We use PCI BIOS's PIR table if it's available $PIR is the
* standard way to do this. Sadly, some machines are not
* standards conforming and have _PIR instead. We shrug and cope
* by looking for both.
*/
if (pcibios_get_version() >= 0x0210 && pt == NULL) {
sigaddr = bios_sigsearch(0, "$PIR", 4, 16, 0);
if (sigaddr == 0)
sigaddr = bios_sigsearch(0, "_PIR", 4, 16, 0);
if (sigaddr != 0) {
pt = (struct PIR_table *)(uintptr_t)
BIOS_PADDRTOVADDR(sigaddr);
for (cv = (u_int8_t *)pt, ck = 0, i = 0;
i < (pt->pt_header.ph_length); i++) {
ck += cv[i];
}
if (ck == 0 && pt->pt_header.ph_length >
sizeof(struct PIR_header)) {
pci_route_table = pt;
pci_route_count = (pt->pt_header.ph_length -
sizeof(struct PIR_header)) /
sizeof(struct PIR_entry);
printf("Using $PIR table, %d entries at %p\n",
pci_route_count, pci_route_table);
if (bootverbose)
pci_print_route_table(pci_route_table,
pci_route_count);
}
}
}
mtx_init(&pcicfg_mtx, "pcicfg", NULL, MTX_SPIN);
opened = 1;
return(1);
}
/*
* Read configuration space register
*/
u_int32_t
pci_cfgregread(int bus, int slot, int func, int reg, int bytes)
{
uint32_t line;
#ifdef APIC_IO
uint32_t pin;
/*
* If we are using the APIC, the contents of the intline
* register will probably be wrong (since they are set up for
* use with the PIC. Rather than rewrite these registers
* (maybe that would be smarter) we trap attempts to read them
* and translate to our private vector numbers.
*/
if ((reg == PCIR_INTLINE) && (bytes == 1)) {
pin = pcireg_cfgread(bus, slot, func, PCIR_INTPIN, 1);
line = pcireg_cfgread(bus, slot, func, PCIR_INTLINE, 1);
if (pin != 0) {
int airq;
airq = pci_apic_irq(bus, slot, pin);
if (airq >= 0) {
/* PCI specific entry found in MP table */
if (airq != line)
undirect_pci_irq(line);
return(airq);
} else {
/*
* PCI interrupts might be redirected
* to the ISA bus according to some MP
* tables. Use the same methods as
* used by the ISA devices devices to
* find the proper IOAPIC int pin.
*/
airq = isa_apic_irq(line);
if ((airq >= 0) && (airq != line)) {
/* XXX: undirect_pci_irq() ? */
undirect_isa_irq(line);
return(airq);
}
}
}
return(line);
}
#else
/*
* Some BIOS writers seem to want to ignore the spec and put
* 0 in the intline rather than 255 to indicate none. The rest of
* the code uses 255 as an invalid IRQ.
*/
if (reg == PCIR_INTLINE && bytes == 1) {
line = pcireg_cfgread(bus, slot, func, PCIR_INTLINE, 1);
return pci_i386_map_intline(line);
}
#endif /* APIC_IO */
return(pcireg_cfgread(bus, slot, func, reg, bytes));
}
/*
* Write configuration space register
*/
void
pci_cfgregwrite(int bus, int slot, int func, int reg, u_int32_t data, int bytes)
{
pcireg_cfgwrite(bus, slot, func, reg, data, bytes);
}
/*
* Route a PCI interrupt
*/
int
pci_cfgintr(int bus, int device, int pin, int oldirq)
{
struct PIR_entry *pe;
int i, irq;
struct bios_regs args;
u_int16_t v;
int already = 0;
int errok = 0;
v = pcibios_get_version();
if (v < 0x0210) {
PRVERB((
"pci_cfgintr: BIOS %x.%02x doesn't support interrupt routing\n",
(v & 0xff00) >> 8, v & 0xff));
return (PCI_INVALID_IRQ);
}
if ((bus < 0) || (bus > 255) || (device < 0) || (device > 255) ||
(pin < 1) || (pin > 4))
return(PCI_INVALID_IRQ);
/*
* Scan the entry table for a contender
*/
for (i = 0, pe = &pci_route_table->pt_entry[0]; i < pci_route_count;
i++, pe++) {
if ((bus != pe->pe_bus) || (device != pe->pe_device))
continue;
/*
* A link of 0 means that this intpin is not connected to
* any other device's interrupt pins and is not connected to
* any of the Interrupt Router's interrupt pins, so we can't
* route it.
*/
if (pe->pe_intpin[pin - 1].link == 0)
continue;
if (pci_cfgintr_valid(pe, pin, oldirq)) {
printf("pci_cfgintr: %d:%d INT%c BIOS irq %d\n", bus,
device, 'A' + pin - 1, oldirq);
return (oldirq);
}
/*
* We try to find a linked interrupt, then we look to see
* if the interrupt is uniquely routed, then we look for
* a virgin interrupt. The virgin interrupt should return
* an interrupt we can route, but if that fails, maybe we
* should try harder to route a different interrupt.
* However, experience has shown that that's rarely the
* failure mode we see.
*/
irq = pci_cfgintr_linked(pe, pin);
if (irq != PCI_INVALID_IRQ)
already = 1;
if (irq == PCI_INVALID_IRQ) {
irq = pci_cfgintr_unique(pe, pin);
if (irq != PCI_INVALID_IRQ)
errok = 1;
}
if (irq == PCI_INVALID_IRQ)
irq = pci_cfgintr_virgin(pe, pin);
if (irq == PCI_INVALID_IRQ)
break;
/*
* Ask the BIOS to route the interrupt. If we picked an
* interrupt that failed, we should really try other
* choices that the BIOS offers us.
*
* For uniquely routed interrupts, we need to try
* to route them on some machines. Yet other machines
* fail to route, so we have to pretend that in that
* case it worked. Isn't pc hardware fun?
*
* NOTE: if we want to whack hardware to do this, then
* I think the right way to do that would be to have
* bridge drivers that do this. I'm not sure that the
* $PIR table would be valid for those interrupt
* routers.
*/
args.eax = PCIBIOS_ROUTE_INTERRUPT;
args.ebx = (bus << 8) | (device << 3);
/* pin value is 0xa - 0xd */
args.ecx = (irq << 8) | (0xa + pin - 1);
if (!already &&
bios32(&args, PCIbios.ventry, GSEL(GCODE_SEL, SEL_KPL)) &&
!errok) {
PRVERB(("pci_cfgintr: ROUTE_INTERRUPT failed.\n"));
return(PCI_INVALID_IRQ);
}
printf("pci_cfgintr: %d:%d INT%c routed to irq %d\n", bus,
device, 'A' + pin - 1, irq);
return(irq);
}
PRVERB(("pci_cfgintr: can't route an interrupt to %d:%d INT%c\n", bus,
device, 'A' + pin - 1));
return(PCI_INVALID_IRQ);
}
/*
* Check to see if an existing IRQ setting is valid.
*/
static int
pci_cfgintr_valid(struct PIR_entry *pe, int pin, int irq)
{
uint32_t irqmask;
if (!PCI_INTERRUPT_VALID(irq))
return (0);
irqmask = pe->pe_intpin[pin - 1].irqs;
if (irqmask & (1 << irq)) {
PRVERB(("pci_cfgintr_valid: BIOS irq %d is valid\n", irq));
return (1);
}
return (0);
}
/*
* Look to see if the routing table claims this pin is uniquely routed.
*/
static int
pci_cfgintr_unique(struct PIR_entry *pe, int pin)
{
int irq;
uint32_t irqmask;
irqmask = pe->pe_intpin[pin - 1].irqs;
if (irqmask != 0 && powerof2(irqmask)) {
irq = ffs(irqmask) - 1;
PRVERB(("pci_cfgintr_unique: hard-routed to irq %d\n", irq));
return(irq);
}
return(PCI_INVALID_IRQ);
}
/*
* Look for another device which shares the same link byte and
* already has a unique IRQ, or which has had one routed already.
*/
static int
pci_cfgintr_linked(struct PIR_entry *pe, int pin)
{
struct PIR_entry *oe;
struct PIR_intpin *pi;
int i, j, irq;
/*
* Scan table slots.
*/
for (i = 0, oe = &pci_route_table->pt_entry[0]; i < pci_route_count;
i++, oe++) {
/* scan interrupt pins */
for (j = 0, pi = &oe->pe_intpin[0]; j < 4; j++, pi++) {
/* don't look at the entry we're trying to match */
if ((pe == oe) && (i == (pin - 1)))
continue;
/* compare link bytes */
if (pi->link != pe->pe_intpin[pin - 1].link)
continue;
/* link destination mapped to a unique interrupt? */
if (pi->irqs != 0 && powerof2(pi->irqs)) {
irq = ffs(pi->irqs) - 1;
PRVERB(("pci_cfgintr_linked: linked (%x) to hard-routed irq %d\n",
pi->link, irq));
return(irq);
}
/*
* look for the real PCI device that matches this
* table entry
*/
irq = pci_cfgintr_search(pe, oe->pe_bus, oe->pe_device,
j, pin);
if (irq != PCI_INVALID_IRQ)
return(irq);
}
}
return(PCI_INVALID_IRQ);
}
/*
* Scan for the real PCI device at (bus)/(device) using intpin (matchpin) and
* see if it has already been assigned an interrupt.
*/
static int
pci_cfgintr_search(struct PIR_entry *pe, int bus, int device, int matchpin, int pin)
{
devclass_t pci_devclass;
device_t *pci_devices;
int pci_count;
device_t *pci_children;
int pci_childcount;
device_t *busp, *childp;
int i, j, irq;
/*
* Find all the PCI busses.
*/
pci_count = 0;
if ((pci_devclass = devclass_find("pci")) != NULL)
devclass_get_devices(pci_devclass, &pci_devices, &pci_count);
/*
* Scan all the PCI busses/devices looking for this one.
*/
irq = PCI_INVALID_IRQ;
for (i = 0, busp = pci_devices; (i < pci_count) && (irq == PCI_INVALID_IRQ);
i++, busp++) {
pci_childcount = 0;
device_get_children(*busp, &pci_children, &pci_childcount);
for (j = 0, childp = pci_children; j < pci_childcount; j++,
childp++) {
if ((pci_get_bus(*childp) == bus) &&
(pci_get_slot(*childp) == device) &&
(pci_get_intpin(*childp) == matchpin)) {
irq = pci_i386_map_intline(pci_get_irq(*childp));
if (irq != PCI_INVALID_IRQ)
PRVERB(("pci_cfgintr_search: linked (%x) to configured irq %d at %d:%d:%d\n",
pe->pe_intpin[pin - 1].link, irq,
pci_get_bus(*childp),
pci_get_slot(*childp),
pci_get_function(*childp)));
break;
}
}
if (pci_children != NULL)
free(pci_children, M_TEMP);
}
if (pci_devices != NULL)
free(pci_devices, M_TEMP);
return(irq);
}
/*
* Pick a suitable IRQ from those listed as routable to this device.
*/
static int
pci_cfgintr_virgin(struct PIR_entry *pe, int pin)
{
int irq, ibit;
/*
* first scan the set of PCI-only interrupts and see if any of these
* are routable
*/
for (irq = 0; irq < 16; irq++) {
ibit = (1 << irq);
/* can we use this interrupt? */
if ((pci_route_table->pt_header.ph_pci_irqs & ibit) &&
(pe->pe_intpin[pin - 1].irqs & ibit)) {
PRVERB(("pci_cfgintr_virgin: using routable PCI-only interrupt %d\n", irq));
return(irq);
}
}
/* life is tough, so just pick an interrupt */
for (irq = 0; irq < 16; irq++) {
ibit = (1 << irq);
if (pe->pe_intpin[pin - 1].irqs & ibit) {
PRVERB(("pci_cfgintr_virgin: using routable interrupt %d\n", irq));
return(irq);
}
}
return(PCI_INVALID_IRQ);
}
static void
pci_print_irqmask(u_int16_t irqs)
{
int i, first;
if (irqs == 0) {
printf("none");
return;
}
first = 1;
for (i = 0; i < 16; i++, irqs >>= 1)
if (irqs & 1) {
if (!first)
printf(" ");
else
first = 0;
printf("%d", i);
}
}
/*
* Dump the contents of a PCI BIOS Interrupt Routing Table to the console.
*/
static void
pci_print_route_table(struct PIR_table *prt, int size)
{
struct PIR_entry *entry;
struct PIR_intpin *intpin;
int i, pin;
printf("PCI-Only Interrupts: ");
pci_print_irqmask(prt->pt_header.ph_pci_irqs);
printf("\nLocation Bus Device Pin Link IRQs\n");
entry = &prt->pt_entry[0];
for (i = 0; i < size; i++, entry++) {
intpin = &entry->pe_intpin[0];
for (pin = 0; pin < 4; pin++, intpin++)
if (intpin->link != 0) {
if (entry->pe_slot == 0)
printf("embedded ");
else
printf("slot %-3d ", entry->pe_slot);
printf(" %3d %3d %c 0x%02x ",
entry->pe_bus, entry->pe_device,
'A' + pin, intpin->link);
pci_print_irqmask(intpin->irqs);
printf("\n");
}
}
}
/*
* See if any interrupts for a given PCI bus are routed in the PIR. Don't
* even bother looking if the BIOS doesn't support routing anyways.
*/
int
pci_probe_route_table(int bus)
{
int i;
u_int16_t v;
v = pcibios_get_version();
if (v < 0x0210)
return (0);
for (i = 0; i < pci_route_count; i++)
if (pci_route_table->pt_entry[i].pe_bus == bus)
return (1);
return (0);
}
/*
* Configuration space access using direct register operations
*/
/* enable configuration space accesses and return data port address */
static int
pci_cfgenable(unsigned bus, unsigned slot, unsigned func, int reg, int bytes)
{
int dataport = 0;
if (bus <= PCI_BUSMAX
&& slot < devmax
&& func <= PCI_FUNCMAX
&& reg <= PCI_REGMAX
&& bytes != 3
&& (unsigned) bytes <= 4
&& (reg & (bytes - 1)) == 0) {
switch (cfgmech) {
case 1:
outl(CONF1_ADDR_PORT, (1 << 31)
| (bus << 16) | (slot << 11)
| (func << 8) | (reg & ~0x03));
dataport = CONF1_DATA_PORT + (reg & 0x03);
break;
case 2:
outb(CONF2_ENABLE_PORT, 0xf0 | (func << 1));
outb(CONF2_FORWARD_PORT, bus);
dataport = 0xc000 | (slot << 8) | reg;
break;
}
}
return (dataport);
}
/* disable configuration space accesses */
static void
pci_cfgdisable(void)
{
switch (cfgmech) {
case 1:
outl(CONF1_ADDR_PORT, 0);
break;
case 2:
outb(CONF2_ENABLE_PORT, 0);
outb(CONF2_FORWARD_PORT, 0);
break;
}
}
static int
pcireg_cfgread(int bus, int slot, int func, int reg, int bytes)
{
int data = -1;
int port;
mtx_lock_spin(&pcicfg_mtx);
port = pci_cfgenable(bus, slot, func, reg, bytes);
if (port != 0) {
switch (bytes) {
case 1:
data = inb(port);
break;
case 2:
data = inw(port);
break;
case 4:
data = inl(port);
break;
}
pci_cfgdisable();
}
mtx_unlock_spin(&pcicfg_mtx);
return (data);
}
static void
pcireg_cfgwrite(int bus, int slot, int func, int reg, int data, int bytes)
{
int port;
mtx_lock_spin(&pcicfg_mtx);
port = pci_cfgenable(bus, slot, func, reg, bytes);
if (port != 0) {
switch (bytes) {
case 1:
outb(port, data);
break;
case 2:
outw(port, data);
break;
case 4:
outl(port, data);
break;
}
pci_cfgdisable();
}
mtx_unlock_spin(&pcicfg_mtx);
}
/* check whether the configuration mechanism has been correctly identified */
static int
pci_cfgcheck(int maxdev)
{
uint32_t id, class;
uint8_t header;
uint8_t device;
int port;
if (bootverbose)
printf("pci_cfgcheck:\tdevice ");
for (device = 0; device < maxdev; device++) {
if (bootverbose)
printf("%d ", device);
port = pci_cfgenable(0, device, 0, 0, 4);
id = inl(port);
if (id == 0 || id == 0xffffffff)
continue;
port = pci_cfgenable(0, device, 0, 8, 4);
class = inl(port) >> 8;
if (bootverbose)
printf("[class=%06x] ", class);
if (class == 0 || (class & 0xf870ff) != 0)
continue;
port = pci_cfgenable(0, device, 0, 14, 1);
header = inb(port);
if (bootverbose)
printf("[hdr=%02x] ", header);
if ((header & 0x7e) != 0)
continue;
if (bootverbose)
printf("is there (id=%08x)\n", id);
pci_cfgdisable();
return (1);
}
if (bootverbose)
printf("-- nothing found\n");
pci_cfgdisable();
return (0);
}
static int
pcireg_cfgopen(void)
{
uint32_t mode1res, oldval1;
uint8_t mode2res, oldval2;
oldval1 = inl(CONF1_ADDR_PORT);
if (bootverbose) {
printf("pci_open(1):\tmode 1 addr port (0x0cf8) is 0x%08x\n",
oldval1);
}
if ((oldval1 & CONF1_ENABLE_MSK) == 0) {
cfgmech = 1;
devmax = 32;
outl(CONF1_ADDR_PORT, CONF1_ENABLE_CHK);
outb(CONF1_ADDR_PORT + 3, 0);
mode1res = inl(CONF1_ADDR_PORT);
outl(CONF1_ADDR_PORT, oldval1);
if (bootverbose)
printf("pci_open(1a):\tmode1res=0x%08x (0x%08lx)\n",
mode1res, CONF1_ENABLE_CHK);
if (mode1res) {
if (pci_cfgcheck(32))
return (cfgmech);
}
outl(CONF1_ADDR_PORT, CONF1_ENABLE_CHK1);
mode1res = inl(CONF1_ADDR_PORT);
outl(CONF1_ADDR_PORT, oldval1);
if (bootverbose)
printf("pci_open(1b):\tmode1res=0x%08x (0x%08lx)\n",
mode1res, CONF1_ENABLE_CHK1);
if ((mode1res & CONF1_ENABLE_MSK1) == CONF1_ENABLE_RES1) {
if (pci_cfgcheck(32))
return (cfgmech);
}
}
oldval2 = inb(CONF2_ENABLE_PORT);
if (bootverbose) {
printf("pci_open(2):\tmode 2 enable port (0x0cf8) is 0x%02x\n",
oldval2);
}
if ((oldval2 & 0xf0) == 0) {
cfgmech = 2;
devmax = 16;
outb(CONF2_ENABLE_PORT, CONF2_ENABLE_CHK);
mode2res = inb(CONF2_ENABLE_PORT);
outb(CONF2_ENABLE_PORT, oldval2);
if (bootverbose)
printf("pci_open(2a):\tmode2res=0x%02x (0x%02x)\n",
mode2res, CONF2_ENABLE_CHK);
if (mode2res == CONF2_ENABLE_RES) {
if (bootverbose)
printf("pci_open(2a):\tnow trying mechanism 2\n");
if (pci_cfgcheck(16))
return (cfgmech);
}
}
cfgmech = 0;
devmax = 0;
return (cfgmech);
}