[patch 08/42] x86: fix "kernel wont boot on a Cyrix MediaGXm(Geode)"

[Greg KH]

2.6.26-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Samuel Sieb <samuel@xxxxxxxx>

commit c6744955d0ec0cb485c28c51eeb7185e260f6172 upstream

Cyrix MediaGXm/Cx5530 Unicorn Revision 1.19.3B has stopped
booting starting at v2.6.22.

The reason is this commit:

> commit f25f64ed5bd3c2932493681bdfdb483ea707da0a
> Author: Juergen Beisert <juergen@xxxxxxxxxxxxxx>
> Date:   Sun Jul 22 11:12:38 2007 +0200
>
>     x86: Replace NSC/Cyrix specific chipset access macros by inlined functions.

this commit activated a macro which was dormant before due to (buggy)
macro side-effects.

I've looked through various datasheets and found that the GXm and GXLV
Geode processors don't have an incrementor.

Remove the incrementor setup entirely.  As the incrementor value
differs according to clock speed and we would hope that the BIOS
configures it correctly, it is probably the right solution.

Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 arch/x86/kernel/cpu/cyrix.c |   18 ------------------
 1 file changed, 18 deletions(-)

--- a/arch/x86/kernel/cpu/cyrix.c
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -134,23 +134,6 @@ static void __cpuinit set_cx86_memwb(voi
 	setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
 }
 
-static void __cpuinit set_cx86_inc(void)
-{
-	unsigned char ccr3;
-
-	printk(KERN_INFO "Enable Incrementor on Cyrix/NSC processor.\n");
-
-	ccr3 = getCx86(CX86_CCR3);
-	setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
-	/* PCR1 -- Performance Control */
-	/* Incrementor on, whatever that is */
-	setCx86(CX86_PCR1, getCx86(CX86_PCR1) | 0x02);
-	/* PCR0 -- Performance Control */
-	/* Incrementor Margin 10 */
-	setCx86(CX86_PCR0, getCx86(CX86_PCR0) | 0x04);
-	setCx86(CX86_CCR3, ccr3);	/* disable MAPEN */
-}
-
 /*
  *	Configure later MediaGX and/or Geode processor.
  */
@@ -174,7 +157,6 @@ static void __cpuinit geode_configure(vo
 
 	set_cx86_memwb();
 	set_cx86_reorder();
-	set_cx86_inc();
 
 	local_irq_restore(flags);
 }

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