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| author | Andy Lutomirski <luto@amacapital.net> | 2013-05-13 23:58:40 +0000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2013-05-31 13:02:52 +1000 |
| commit | d0d98eedee2178c803dd824bb09f52b0e2ac1811 (patch) | |
| tree | 302ece15c574dc061b1dea4e67125c7b01342154 /arch/x86/include | |
| parent | e81f3d81e282a156b47c1c2c09a1976e34073060 (diff) | |
| download | op-kernel-dev-d0d98eedee2178c803dd824bb09f52b0e2ac1811.zip op-kernel-dev-d0d98eedee2178c803dd824bb09f52b0e2ac1811.tar.gz | |
Add arch_phys_wc_{add, del} to manipulate WC MTRRs if needed
Several drivers currently use mtrr_add through various #ifdef guards
and/or drm wrappers. The vast majority of them want to add WC MTRRs
on x86 systems and don't actually need the MTRR if PAT (i.e.
ioremap_wc, etc) are working.
arch_phys_wc_add and arch_phys_wc_del are new functions, available
on all architectures and configurations, that add WC MTRRs on x86 if
needed (and handle errors) and do nothing at all otherwise. They're
also easier to use than mtrr_add and mtrr_del, so the call sites can
be simplified.
As an added benefit, this will avoid wasting MTRRs and possibly
warning pointlessly on PAT-supporting systems.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/io.h | 7 | ||||
| -rw-r--r-- | arch/x86/include/asm/mtrr.h | 10 |
2 files changed, 16 insertions, 1 deletions
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index d8e8eef..34f69cb 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -345,4 +345,11 @@ extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, #define IO_SPACE_LIMIT 0xffff +#ifdef CONFIG_MTRR +extern int __must_check arch_phys_wc_add(unsigned long base, + unsigned long size); +extern void arch_phys_wc_del(int handle); +#define arch_phys_wc_add arch_phys_wc_add +#endif + #endif /* _ASM_X86_IO_H */ diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h index e235582..f768f62 100644 --- a/arch/x86/include/asm/mtrr.h +++ b/arch/x86/include/asm/mtrr.h @@ -26,7 +26,10 @@ #include <uapi/asm/mtrr.h> -/* The following functions are for use by other drivers */ +/* + * The following functions are for use by other drivers that cannot use + * arch_phys_wc_add and arch_phys_wc_del. + */ # ifdef CONFIG_MTRR extern u8 mtrr_type_lookup(u64 addr, u64 end); extern void mtrr_save_fixed_ranges(void *); @@ -45,6 +48,7 @@ extern void mtrr_aps_init(void); extern void mtrr_bp_restore(void); extern int mtrr_trim_uncached_memory(unsigned long end_pfn); extern int amd_special_default_mtrr(void); +extern int phys_wc_to_mtrr_index(int handle); # else static inline u8 mtrr_type_lookup(u64 addr, u64 end) { @@ -80,6 +84,10 @@ static inline int mtrr_trim_uncached_memory(unsigned long end_pfn) static inline void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi) { } +static inline int phys_wc_to_mtrr_index(int handle) +{ + return -1; +} #define mtrr_ap_init() do {} while (0) #define mtrr_bp_init() do {} while (0) |
