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 <[email protected]> Reported-by: AKASHI Takahiro <[email protected]> Acked-by: Will Deacon <[email protected]> Signed-off-by: Suzuki K. Poulose <[email protected]> Signed-off-by: Catalin Marinas <[email protected]>
josf · Nov 26, 2015 · 1944bf8 · 1944bf8
1 parent 4f0a606
commit 1944bf8
Showing 1 changed file with 4 additions and 2 deletions.
diff --git 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);
 }