arm64: debug: Treat the BRPs/WRPs as unsigned

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>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h
index e54415ec693571d1d4195d57b1928e2e58173353..9732908bfc8a54b546c4cab40802f70a56b36fce 100644 (file)
--- 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);
 }