diff options
| author | Michael Shalayeff <mickey@cvs.openbsd.org> | 2006-03-29 15:02:28 +0000 |
|---|---|---|
| committer | Michael Shalayeff <mickey@cvs.openbsd.org> | 2006-03-29 15:02:28 +0000 |
| commit | 09eb6192a5a08271cad5e11ed7505731a1492f06 (patch) | |
| tree | d08297e3fcc7d06629fa131045f9ba9172174ec1 | |
| parent | 42bb20655906893b9b89242a5b1df1b37fd48676 (diff) | |
workaround for intel errata p53 -- follow lapic writes w/ a read; toby@ kettenis@ ok
| -rw-r--r-- | sys/arch/i386/include/i82489var.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/sys/arch/i386/include/i82489var.h b/sys/arch/i386/include/i82489var.h index 3c4632872ce..8bdf4eda158 100644 --- a/sys/arch/i386/include/i82489var.h +++ b/sys/arch/i386/include/i82489var.h @@ -1,4 +1,4 @@ -/* $OpenBSD: i82489var.h,v 1.2 2004/06/13 21:49:16 niklas Exp $ */ +/* $OpenBSD: i82489var.h,v 1.3 2006/03/29 15:02:27 mickey Exp $ */ /* $NetBSD: i82489var.h,v 1.1.2.2 2000/02/21 18:46:14 sommerfeld Exp $ */ /*- @@ -62,6 +62,14 @@ i82489_writereg(reg, val) { *((volatile u_int32_t *)(((volatile u_int8_t *)local_apic) + reg)) = val; + /* + * intel xeon errata p53: + * write to a lapic register sometimes may appear to have not occured + * workaround: + * follow write with a read [from id register] + */ + val = *((volatile u_int32_t *)(((volatile u_int8_t *)local_apic) + + LAPIC_ID)); } /* |