linux_dsm_epyc7002/include/asm-x86/pat.h
Thomas Gleixner 8d4a430085 x86: cleanup PAT cpu validation
Move the scattered checks for PAT support to a single function. Its
moved to addon_cpuid_features.c as this file is shared between 32 and
64 bit.

Remove the manipulation of the PAT feature bit and just disable PAT in
the PAT layer, based on the PAT bit provided by the CPU and the
current CPU version/model white list.

Change the boot CPU check so it works on Voyager somewhere in the
future as well :) Also panic, when a secondary has PAT disabled but
the primary one has alrady switched to PAT. We have no way to undo
that.

The white list is kept for now to ensure that we can rely on known to
work CPU types and concentrate on the software induced problems
instead of fighthing CPU erratas and subtle wreckage caused by not yet
verified CPUs. Once the PAT code has stabilized enough, we can remove
the white list and open the can of worms.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-08 15:43:51 +02:00

25 lines
514 B
C

#ifndef _ASM_PAT_H
#define _ASM_PAT_H 1
#include <linux/types.h>
#ifdef CONFIG_X86_PAT
extern int pat_wc_enabled;
extern void validate_pat_support(struct cpuinfo_x86 *c);
#else
static const int pat_wc_enabled = 0;
static inline void validate_pat_support(struct cpuinfo_x86 *c) { }
#endif
extern void pat_init(void);
extern int reserve_memtype(u64 start, u64 end,
unsigned long req_type, unsigned long *ret_type);
extern int free_memtype(u64 start, u64 end);
extern void pat_disable(char *reason);
#endif