Re: [Patch] x86, x86_64: fix cpu model for family 0x6

[Siddha, Suresh B]

On Fri, Sep 30, 2005 at 03:09:46PM +0200, Petr Vandrovec wrote:
> Siddha, Suresh B wrote:
> > -		if (c->x86 == 0xf) {
> > +		if (c->x86 == 0xf)
> >  			c->x86 += (tfms >> 20) & 0xff;
> > +		if (c->x86 == 0x6 || c->x86 == 0xf)
> 
> Are you sure this is correct?  You just incremented c->x86 by extended
> family, so I believe test should be
> 
>                  if (c->x86 == 0x6 || c->x86 >= 0xf)

My bad. Your suggestion might work. But let me just follow what SDM Vol-2a
says here. New patch appended.

Andi, please apply.

thanks,
suresh

--

According to cpuid instruction in IA32 SDM-Vol2, when computing cpu model,
we need to consider extended model ID for family 0x6 also.
  
Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>

--- linux-2.6.14-rc2-git7/arch/x86_64/kernel/setup.c~	2005-09-29 18:05:26.503939536 -0700
+++ linux-2.6.14-rc2-git7/arch/x86_64/kernel/setup.c	2005-09-30 10:17:37.964209680 -0700
@@ -1059,10 +1059,10 @@ void __cpuinit early_identify_cpu(struct
 		c->x86 = (tfms >> 8) & 0xf;
 		c->x86_model = (tfms >> 4) & 0xf;
 		c->x86_mask = tfms & 0xf;
-		if (c->x86 == 0xf) {
-			c->x86 += (tfms >> 20) & 0xff;
+		if (c->x86 == 0x6 || c->x86 == 0xf)
 			c->x86_model += ((tfms >> 16) & 0xF) << 4;
-		} 
+		if (c->x86 == 0xf)
+			c->x86 += (tfms >> 20) & 0xff;
 		if (c->x86_capability[0] & (1<<19)) 
 			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
 	} else {
--- linux-2.6.14-rc2-git7/arch/x86_64/kernel/setup.c~	2005-09-29 18:05:26.503939536 -0700
+++ linux-2.6.14-rc2-git7/arch/x86_64/kernel/setup.c	2005-09-30 10:17:37.964209680 -0700
@@ -1059,10 +1059,10 @@ void __cpuinit early_identify_cpu(struct
 		c->x86 = (tfms >> 8) & 0xf;
 		c->x86_model = (tfms >> 4) & 0xf;
 		c->x86_mask = tfms & 0xf;
-		if (c->x86 == 0xf) {
-			c->x86 += (tfms >> 20) & 0xff;
+		if (c->x86 == 0x6 || c->x86 == 0xf)
 			c->x86_model += ((tfms >> 16) & 0xF) << 4;
-		} 
+		if (c->x86 == 0xf)
+			c->x86 += (tfms >> 20) & 0xff;
 		if (c->x86_capability[0] & (1<<19)) 
 			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
 	} else {
-
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