diff options
| author | Marco S Hyman <marc@cvs.openbsd.org> | 1998-02-11 01:27:30 +0000 |
|---|---|---|
| committer | Marco S Hyman <marc@cvs.openbsd.org> | 1998-02-11 01:27:30 +0000 |
| commit | 6206d519a4d9d51d2be6bf08af045a6921be0604 (patch) | |
| tree | f616aeaf0412268ee70a9eb639c7125ded34f638 /sys/arch | |
| parent | 2203688ff516ce2e93770314d6309c08b579b576 (diff) | |
From NetBSD: sun4m anti crash code in IOMMU_FLUSH{PAGE,ALL}
Diffstat (limited to 'sys/arch')
| -rw-r--r-- | sys/arch/sparc/sparc/iommureg.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/sys/arch/sparc/sparc/iommureg.h b/sys/arch/sparc/sparc/iommureg.h index c1021afcc55..8d49bf68b3f 100644 --- a/sys/arch/sparc/sparc/iommureg.h +++ b/sys/arch/sparc/sparc/iommureg.h @@ -1,4 +1,4 @@ -/* $OpenBSD: iommureg.h,v 1.3 1997/09/17 06:47:17 downsj Exp $ */ +/* $OpenBSD: iommureg.h,v 1.4 1998/02/11 01:27:29 marc Exp $ */ /* $NetBSD: iommureg.h,v 1.3 1997/09/14 19:16:04 pk Exp $ */ /* @@ -60,11 +60,19 @@ struct iommureg { #define IOMMU_FLPG_VADDR 0xfffff000 #define IOMMU_FLUSH_MASK 0xfffff000 +/* + * Read something back from the IOMMU control space after writing + * to a flush register to drain write buffers (?). This seems to + * avoid utter lossage on some machines (SS4s & SS5s) where our caller + * would see some of its local (`%lx') registers trashed. + */ #define IOMMU_FLUSHPAGE(sc, va) do { \ (sc)->sc_reg->io_flushpage = (va) & IOMMU_FLUSH_MASK; \ + (*(volatile u_int32_t *)&(sc)->sc_reg->io_bar); \ } while (0); #define IOMMU_FLUSHALL(sc) do { \ (sc)->sc_reg->io_flashclear = 0; \ + (*(volatile u_int32_t *)&(sc)->sc_reg->io_bar); \ } while (0) /* to pte.h ? */ |