[PATCH 3/5] arm64: debug: Treat the BRPs/WRPs as unsigned

Suzuki K. Poulose
2015-11-18T17:10:22Z

IDAA64DFR0_EL1: BRPs and WRPs are unsigned values. Use
the appropriate helpers to extract those fields.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
---
arch/arm64/include/asm/hw_breakpoint.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h
index e54415e..9732908 100644
--- a/arch/arm64/include/asm/hw_breakpoint.h
+++ b/arch/arm64/include/asm/hw_breakpoint.h
@@ -138,16 +138,18 @@ extern struct pmu perf_ops_bp;
/* Determine number of BRP registers available. */
static inline int get_num_brps(void)
{
+ u64 dfr0 = read_system_reg(SYS_ID_AA64DFR0_EL1);
return 1 +
- cpuid_feature_extract_field(read_system_reg(SYS_ID_AA64DFR0_EL1),
+ cpuid_feature_extract_unsigned_field(dfr0,
ID_AA64DFR0_BRPS_SHIFT);
}

/* Determine number of WRP registers available. */
static inline int get_num_wrps(void)
{
+ u64 dfr0 = read_system_reg(SYS_ID_AA64DFR0_EL1);
return 1 +
- cpuid_feature_extract_field(read_system_reg(SYS_ID_AA64DFR0_EL1),
+ cpuid_feature_extract_unsigned_field(dfr0,
ID_AA64DFR0_WRPS_SHIFT);
}

--
1.7.9.5