linux_dsm_epyc7002/arch/i386/kernel/acpi/earlyquirk.c
Andi Kleen fa18f477d0 [PATCH] x86: Add acpi_user_timer_override option for Asus boards
Timer overrides are normally disabled on Nvidia board because
they are commonly wrong, except on new ones with HPET support.
Unfortunately there are quite some Asus boards around that
don't have HPET, but need a timer override.

We don't know yet how to handle this transparently,
but at least add a command line option to force the timer override
and let them boot.

Cc: len.brown@intel.com

Signed-off-by: Andi Kleen <ak@suse.de>
2006-11-14 16:57:46 +01:00

87 lines
2.1 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 nvidia_hpet_detected __initdata;
static int __init nvidia_hpet_check(unsigned long phys, unsigned long size)
{
nvidia_hpet_detected = 1;
return 0;
}
#endif
static int __init check_bridge(int vendor, int device)
{
#ifdef CONFIG_ACPI
/* According to Nvidia all timer overrides are bogus unless HPET
is enabled. */
if (!acpi_use_timer_override && vendor == PCI_VENDOR_ID_NVIDIA) {
nvidia_hpet_detected = 0;
acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
if (nvidia_hpet_detected == 0) {
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;
}
}
}
}