Some of those functions try to adjust the CPU features, for example
to remove NAP support on some revisions. However, they seem to use
r5 as an index into the CPU table entry, which might have been right
a long time ago but no longer is. r4 is the right register to use.
This probably caused some off behaviours on some PowerMac variants
using 750cx or 7455 processor revisions.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
---
Can somebody with one of these PowerMacs test this ? I only managed to
find a 7448 which not directly affected...
In absence of good testing I would appreciate a close inspection of the patch
by different pairs of eyes :-)
Cheers,
Ben.
diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S
b/arch/powerpc/kernel/cpu_setup_6xx.S
index 55cba4a..f8cd9fb 100644
--- a/arch/powerpc/kernel/cpu_setup_6xx.S
+++ b/arch/powerpc/kernel/cpu_setup_6xx.S
@@ -18,7 +18,7 @@
#include <asm/mmu.h>
_GLOBAL(__setup_cpu_603)
- mflr r4
+ mflr r5
BEGIN_MMU_FTR_SECTION
li r10,0
mtspr SPRN_SPRG_603_LRU,r10 /* init SW LRU tracking */
@@ -27,60 +27,60 @@ BEGIN_FTR_SECTION
bl __init_fpu_registers
END_FTR_SECTION_IFCLR(CPU_FTR_FPU_UNAVAILABLE)
bl setup_common_caches
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_604)
- mflr r4
+ mflr r5
bl setup_common_caches
bl setup_604_hid0
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_750)
- mflr r4
+ mflr r5
bl __init_fpu_registers
bl setup_common_caches
bl setup_750_7400_hid0
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_750cx)
- mflr r4
+ mflr r5
bl __init_fpu_registers
bl setup_common_caches
bl setup_750_7400_hid0
bl setup_750cx
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_750fx)
- mflr r4
+ mflr r5
bl __init_fpu_registers
bl setup_common_caches
bl setup_750_7400_hid0
bl setup_750fx
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_7400)
- mflr r4
+ mflr r5
bl __init_fpu_registers
bl setup_7400_workarounds
bl setup_common_caches
bl setup_750_7400_hid0
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_7410)
- mflr r4
+ mflr r5
bl __init_fpu_registers
bl setup_7410_workarounds
bl setup_common_caches
bl setup_750_7400_hid0
li r3,0
mtspr SPRN_L2CR2,r3
- mtlr r4
+ mtlr r5
blr
_GLOBAL(__setup_cpu_745x)
- mflr r4
+ mflr r5
bl setup_common_caches
bl setup_745x_specifics
- mtlr r4
+ mtlr r5
blr
/* Enable caches for 603's, 604, 750 & 7400 */
@@ -194,10 +194,10 @@ setup_750cx:
cror 4*cr0+eq,4*cr0+eq,4*cr1+eq
cror 4*cr0+eq,4*cr0+eq,4*cr2+eq
bnelr
- lwz r6,CPU_SPEC_FEATURES(r5)
+ lwz r6,CPU_SPEC_FEATURES(r4)
li r7,CPU_FTR_CAN_NAP
andc r6,r6,r7
- stw r6,CPU_SPEC_FEATURES(r5)
+ stw r6,CPU_SPEC_FEATURES(r4)
blr
/* 750fx specific
@@ -225,12 +225,12 @@ BEGIN_FTR_SECTION
andis. r11,r11,L3CR_L3E@h
beq 1f
END_FTR_SECTION_IFSET(CPU_FTR_L3CR)
- lwz r6,CPU_SPEC_FEATURES(r5)
+ lwz r6,CPU_SPEC_FEATURES(r4)
andi. r0,r6,CPU_FTR_L3_DISABLE_NAP
beq 1f
li r7,CPU_FTR_CAN_NAP
andc r6,r6,r7
- stw r6,CPU_SPEC_FEATURES(r5)
+ stw r6,CPU_SPEC_FEATURES(r4)
1:
mfspr r11,SPRN_HID0
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