acrn-kernel/arch/x86/kernel/acpi/earlyquirk_32.c

85 lines
2.0 KiB
C

/*
* Do early PCI probing for bug detection when the main PCI subsystem is
* not up yet.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <asm/pci-direct.h>
#include <asm/acpi.h>
#include <asm/apic.h>
#ifdef CONFIG_ACPI
static int __init nvidia_hpet_check(struct acpi_table_header *header)
{
return 0;
}
#endif
static int __init check_bridge(int vendor, int device)
{
#ifdef CONFIG_ACPI
static int warned;
/* According to Nvidia all timer overrides are bogus unless HPET
is enabled. */
if (!acpi_use_timer_override && vendor == PCI_VENDOR_ID_NVIDIA) {
if (!warned && acpi_table_parse(ACPI_SIG_HPET,
nvidia_hpet_check)) {
warned = 1;
acpi_skip_timer_override = 1;
printk(KERN_INFO "Nvidia board "
"detected. Ignoring ACPI "
"timer override.\n");
printk(KERN_INFO "If you got timer trouble "
"try acpi_use_timer_override\n");
}
}
#endif
if (vendor == PCI_VENDOR_ID_ATI && timer_over_8254 == 1) {
timer_over_8254 = 0;
printk(KERN_INFO "ATI board detected. Disabling timer routing "
"over 8254.\n");
}
return 0;
}
void __init check_acpi_pci(void)
{
int num, slot, func;
/* Assume the machine supports type 1. If not it will
always read ffffffff and should not have any side effect.
Actually a few buggy systems can machine check. Allow the user
to disable it by command line option at least -AK */
if (!early_pci_allowed())
return;
/* Poor man's PCI discovery */
for (num = 0; num < 32; num++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
u32 class;
u32 vendor;
class = read_pci_config(num, slot, func,
PCI_CLASS_REVISION);
if (class == 0xffffffff)
break;
if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
continue;
vendor = read_pci_config(num, slot, func,
PCI_VENDOR_ID);
if (check_bridge(vendor & 0xffff, vendor >> 16))
return;
}
}
}
}