mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 11:18:45 +07:00
0637a70a5d
Some buggy systems can machine check when config space accesses happen for some non existent devices. i386/x86-64 do some early device scans that might trigger this. Allow pci=noearly to disable this. Also when type 1 is disabling also don't do any early accesses which are always type1. This moves the pci= configuration parsing to be a early parameter. I don't think this can break anything because it only changes a single global that is only used by PCI. Cc: gregkh@suse.de Cc: Trammell Hudson <hudson@osresearch.net> Signed-off-by: Andi Kleen <ak@suse.de>
53 lines
1.3 KiB
C
53 lines
1.3 KiB
C
#include <linux/kernel.h>
|
|
#include <linux/pci.h>
|
|
#include <asm/pci-direct.h>
|
|
#include <asm/io.h>
|
|
#include "pci.h"
|
|
|
|
/* Direct PCI access. This is used for PCI accesses in early boot before
|
|
the PCI subsystem works. */
|
|
|
|
#define PDprintk(x...)
|
|
|
|
u32 read_pci_config(u8 bus, u8 slot, u8 func, u8 offset)
|
|
{
|
|
u32 v;
|
|
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
|
|
v = inl(0xcfc);
|
|
if (v != 0xffffffff)
|
|
PDprintk("%x reading 4 from %x: %x\n", slot, offset, v);
|
|
return v;
|
|
}
|
|
|
|
u8 read_pci_config_byte(u8 bus, u8 slot, u8 func, u8 offset)
|
|
{
|
|
u8 v;
|
|
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
|
|
v = inb(0xcfc + (offset&3));
|
|
PDprintk("%x reading 1 from %x: %x\n", slot, offset, v);
|
|
return v;
|
|
}
|
|
|
|
u16 read_pci_config_16(u8 bus, u8 slot, u8 func, u8 offset)
|
|
{
|
|
u16 v;
|
|
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
|
|
v = inw(0xcfc + (offset&2));
|
|
PDprintk("%x reading 2 from %x: %x\n", slot, offset, v);
|
|
return v;
|
|
}
|
|
|
|
void write_pci_config(u8 bus, u8 slot, u8 func, u8 offset,
|
|
u32 val)
|
|
{
|
|
PDprintk("%x writing to %x: %x\n", slot, offset, val);
|
|
outl(0x80000000 | (bus<<16) | (slot<<11) | (func<<8) | offset, 0xcf8);
|
|
outl(val, 0xcfc);
|
|
}
|
|
|
|
int early_pci_allowed(void)
|
|
{
|
|
return (pci_probe & (PCI_PROBE_CONF1|PCI_PROBE_NOEARLY)) ==
|
|
PCI_PROBE_CONF1;
|
|
}
|