Attachment 212294 Details for Bug 244705 – reverts the breaking change

[patch] reverts the breaking change

revert-tsc-1.diff (text/plain), 1.29 KB, created by Theron Tarigo on 2020-03-09 23:41:30 UTC

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Creator: Theron Tarigo

Created: 2020-03-09 23:41:30 UTC

Size: 1.29 KB

patch

obsolete

>Index: sys/x86/x86/tsc.c
>===================================================================
>--- sys/x86/x86/tsc.c	(revision 358826)
>+++ sys/x86/x86/tsc.c	(working copy)
>@@ -134,11 +134,7 @@
> 
> /*
>  * Calculate TSC frequency using information from the CPUID leaf 0x15
>- * 'Time Stamp Counter and Nominal Core Crystal Clock'.  If leaf 0x15
>- * is not functional, as it is on Skylake/Kabylake, try 0x16 'Processor
>- * Frequency Information'.  Leaf 0x16 is described in the SDM as
>- * informational only, but if 0x15 did not work, and TSC calibration
>- * is disabled, it is the best we can get at all.  It should still be
>+ * 'Time Stamp Counter and Nominal Core Crystal Clock'.  It should be
>  * an improvement over the parsing of the CPU model name in
>  * tsc_freq_intel(), when available.
>  */
>@@ -150,20 +146,10 @@
> 	if (cpu_high < 0x15)
> 		return (false);
> 	do_cpuid(0x15, regs);
>-	if (regs[0] != 0 && regs[1] != 0 && regs[2] != 0) {
>-		tsc_freq = (uint64_t)regs[2] * regs[1] / regs[0];
>-		return (true);
>-	}
>-
>-	if (cpu_high < 0x16)
>+	if (regs[0] == 0 || regs[1] == 0 || regs[2] == 0)
> 		return (false);
>-	do_cpuid(0x16, regs);
>-	if (regs[0] != 0) {
>-		tsc_freq = (uint64_t)regs[0] * 1000000;
>-		return (true);
>-	}
>-
>-	return (false);
>+	tsc_freq = (uint64_t)regs[2] * regs[1] / regs[0];
>+	return (true);
> }
> 
> static void

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Attachments on bug 244705: 212294