diff options
| author | Michael Shalayeff <mickey@cvs.openbsd.org> | 2004-02-23 06:29:55 +0000 |
|---|---|---|
| committer | Michael Shalayeff <mickey@cvs.openbsd.org> | 2004-02-23 06:29:55 +0000 |
| commit | 8dd789037018006b863e243c5658c72301486475 (patch) | |
| tree | 23aacd8b7a93a3a93429ada24e8d8e3fc335cf01 /sys/arch/amd64/include | |
| parent | 531d7a974de99ede3f382e61f63a66fb0bb27e62 (diff) | |
provide _barrier method w/ {l,s,m}fence instructions
Diffstat (limited to 'sys/arch/amd64/include')
| -rw-r--r-- | sys/arch/amd64/include/bus.h | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/sys/arch/amd64/include/bus.h b/sys/arch/amd64/include/bus.h index 4a1c326b8fc..e4266dc1c1c 100644 --- a/sys/arch/amd64/include/bus.h +++ b/sys/arch/amd64/include/bus.h @@ -1,4 +1,4 @@ -/* $OpenBSD: bus.h,v 1.1 2004/01/28 01:39:39 mickey Exp $ */ +/* $OpenBSD: bus.h,v 1.2 2004/02/23 06:29:54 mickey Exp $ */ /* $NetBSD: bus.h,v 1.6 1996/11/10 03:19:25 thorpej Exp $ */ /*- @@ -931,22 +931,25 @@ x86_memio_copy_region_4(bus_space_tag_t t, /* * Bus read/write barrier methods. - * - * void bus_space_barrier(bus_space_tag_t tag, - * bus_space_handle_t bsh, bus_size_t offset, - * bus_size_t len, int flags); - * - * Note: the x86 does not currently require barriers, but we must - * provide the flags to MI code. */ -#define bus_space_barrier(t, h, o, l, f) \ - ((void)((void)(t), (void)(h), (void)(o), (void)(l), (void)(f))) #define BUS_SPACE_BARRIER_READ 0x01 /* force read barrier */ #define BUS_SPACE_BARRIER_WRITE 0x02 /* force write barrier */ /* Compatibility defines */ #define BUS_BARRIER_READ BUS_SPACE_BARRIER_READ #define BUS_BARRIER_WRITE BUS_SPACE_BARRIER_WRITE +static __inline void +bus_space_barrier(bus_space_tag_t tag, bus_space_handle_t bsh, + bus_size_t offset, bus_size_t len, int flags) +{ + if (flags == (BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)) + __asm __volatile("mfence"); + else if (flags == BUS_SPACE_BARRIER_WRITE) + __asm __volatile("sfence"); + else + __asm __volatile("lfence"); +} + /* * Flags used in various bus DMA methods. */ |