diff options
| -rw-r--r-- | arch/arm/include/asm/cputype.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index 8c25dc4e9851..9672e978d50d 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h | |||
| @@ -89,13 +89,18 @@ extern unsigned int processor_id; | |||
| 89 | __val; \ | 89 | __val; \ |
| 90 | }) | 90 | }) |
| 91 | 91 | ||
| 92 | /* | ||
| 93 | * The memory clobber prevents gcc 4.5 from reordering the mrc before | ||
| 94 | * any is_smp() tests, which can cause undefined instruction aborts on | ||
| 95 | * ARM1136 r0 due to the missing extended CP15 registers. | ||
| 96 | */ | ||
| 92 | #define read_cpuid_ext(ext_reg) \ | 97 | #define read_cpuid_ext(ext_reg) \ |
| 93 | ({ \ | 98 | ({ \ |
| 94 | unsigned int __val; \ | 99 | unsigned int __val; \ |
| 95 | asm("mrc p15, 0, %0, c0, " ext_reg \ | 100 | asm("mrc p15, 0, %0, c0, " ext_reg \ |
| 96 | : "=r" (__val) \ | 101 | : "=r" (__val) \ |
| 97 | : \ | 102 | : \ |
| 98 | : "cc"); \ | 103 | : "memory"); \ |
| 99 | __val; \ | 104 | __val; \ |
| 100 | }) | 105 | }) |
| 101 | 106 | ||