coresight: trbe: Directly use ID_AA64DFR0_EL1_TraceBuffer_IMP

is_trbe_available() checks for the TRBE support via extracting TraceBuffer
field value from ID_AA64DFR0_EL1, and ensures that it is implemented. This
replaces the open encoding '0b0001' with 'ID_AA64DFR0_EL1_TraceBuffer_IMP'
which is now available via sysreg tools. Functional change is not intended.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230802063658.1069813-1-anshuman.khandual@arm.com

diff --git a/drivers/hwtracing/coresight/coresight-trbe.h b/drivers/hwtracing/coresight/coresight-trbe.h
index 77cbb5c6387833a3892112fc9a6aa3b778a62713..e915e749be55150d95f44e19fd1a874d190174b2 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-trbe.h
+++ b/drivers/hwtracing/coresight/coresight-trbe.h
@@ -23,7 +23,7 @@ static inline bool is_trbe_available(void)
        unsigned int trbe = cpuid_feature_extract_unsigned_field(aa64dfr0,
                                                                 ID_AA64DFR0_EL1_TraceBuffer_SHIFT);
 
-       return trbe >= 0b0001;
+       return trbe >= ID_AA64DFR0_EL1_TraceBuffer_IMP;
 }
 
 static inline bool is_trbe_enabled(void)