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authorThomas Nordin <nordin@cvs.openbsd.org>2002-09-24 00:06:24 +0000
committerThomas Nordin <nordin@cvs.openbsd.org>2002-09-24 00:06:24 +0000
commitab4b95ffcece79129777c12ef6f57359cad0ac57 (patch)
treeb668d32e880f909117fb0b77520f400df7e72f1e /sys/arch/i386
parentbd4cd4bc31f25cda237420e9652344299167b4cf (diff)
Restore pentium_microtime, testing by henning@, millert@. ok deraadt@
Diffstat (limited to 'sys/arch/i386')
-rw-r--r--sys/arch/i386/i386/microtime.s30
-rw-r--r--sys/arch/i386/include/cpu.h17
2 files changed, 31 insertions, 16 deletions
diff --git a/sys/arch/i386/i386/microtime.s b/sys/arch/i386/i386/microtime.s
index 22ad3b82224..8ec301e0dc6 100644
--- a/sys/arch/i386/i386/microtime.s
+++ b/sys/arch/i386/i386/microtime.s
@@ -1,4 +1,4 @@
-/* $OpenBSD: microtime.s,v 1.15 2002/07/06 19:14:20 nordin Exp $ */
+/* $OpenBSD: microtime.s,v 1.16 2002/09/24 00:06:22 nordin Exp $ */
/* $NetBSD: microtime.s,v 1.16 1995/04/17 12:06:47 cgd Exp $ */
/*-
@@ -48,7 +48,13 @@
#ifndef HZ
ENTRY(microtime)
+#if defined(I586_CPU) || defined(I686_CPU)
+ movl _pentium_mhz, %ecx
+ testl %ecx, %ecx
+ jne pentium_microtime
+#else
xorl %ecx,%ecx
+#endif
movb $(TIMER_SEL0|TIMER_LATCH),%al
pushfl
@@ -134,12 +140,30 @@ common_microtime:
ret
#if defined(I586_CPU) || defined(I686_CPU)
- # XXX: Move to machdep.c?
-
.data
.globl _pentium_base_tsc
.comm _pentium_base_tsc,8
.text
+
+ .align 2, 0x90
+pentium_microtime:
+ pushfl
+ cli
+ .byte 0x0f, 0x31 # RDTSC
+ subl _pentium_base_tsc,%eax
+ sbbl _pentium_base_tsc+4,%edx
+ /*
+ * correct the high word first so we won't
+ * receive a result overflow aka div/0 fault
+ */
+ pushl %eax
+ movl %edx, %eax
+ shll $16, %edx
+ divw %cx
+ movzwl %dx, %edx
+ popl %eax
+ divl %ecx
+ jmp common_microtime
#endif
#endif
diff --git a/sys/arch/i386/include/cpu.h b/sys/arch/i386/include/cpu.h
index 7c73020e71f..4e6f61855b2 100644
--- a/sys/arch/i386/include/cpu.h
+++ b/sys/arch/i386/include/cpu.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: cpu.h,v 1.42 2002/06/07 21:33:43 nordin Exp $ */
+/* $OpenBSD: cpu.h,v 1.43 2002/09/24 00:06:23 nordin Exp $ */
/* $NetBSD: cpu.h,v 1.35 1996/05/05 19:29:26 christos Exp $ */
/*-
@@ -101,23 +101,14 @@ void delay(int);
void calibrate_cyclecounter(void);
#ifndef HZ
extern u_quad_t pentium_base_tsc;
-#define CPU_CLOCKUPDATE(otime, ntime) \
+#define CPU_CLOCKUPDATE() \
do { \
if (pentium_mhz) { \
__asm __volatile("cli\n" \
- "movl (%3), %%eax\n" \
- "movl %%eax, (%2)\n" \
- "movl 4(%3), %%eax\n" \
- "movl %%eax, 4(%2)\n" \
".byte 0xf, 0x31\n" \
"sti\n" \
- "#%0 %1 %2 %3" \
- : "=m" (*otime), \
- "=A" (pentium_base_tsc) \
- : "c" (otime), "b" (ntime)); \
- } \
- else { \
- *(otime) = *(ntime); \
+ : "=A" (pentium_base_tsc) \
+ : ); \
} \
} while (0)
#endif