diff options
| author | James Clark <james.clark@linaro.org> | 2025-03-25 11:58:47 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-07-06 11:01:34 +0200 |
| commit | c7bfbba30fd1092a57ff6d15911c6e062d864083 (patch) | |
| tree | b8b1c75c7be4af81ac8dc306fb8167af2fc0f8b4 | |
| parent | a0baf4d78b2bed782b5851751d80e9ad21a52372 (diff) | |
coresight: Only check bottom two claim bits
[ Upstream commit a4e65842e1142aa18ef36113fbd81d614eaefe5a ]
The use of the whole register and == could break the claim mechanism if
any of the other bits are used in the future. The referenced doc "PSCI -
ARM DEN 0022D" also says to only read and clear the bottom two bits.
Use FIELD_GET() to extract only the relevant part.
Reviewed-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250325-james-coresight-claim-tags-v4-2-dfbd3822b2e5@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-core.c | 3 | ||||
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-priv.h | 1 |
2 files changed, 3 insertions, 1 deletions
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index c7e35a431ab0..b7941d8abbfe 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -97,7 +97,8 @@ coresight_find_out_connection(struct coresight_device *src_dev, static inline u32 coresight_read_claim_tags(struct coresight_device *csdev) { - return csdev_access_relaxed_read32(&csdev->access, CORESIGHT_CLAIMCLR); + return FIELD_GET(CORESIGHT_CLAIM_MASK, + csdev_access_relaxed_read32(&csdev->access, CORESIGHT_CLAIMCLR)); } static inline bool coresight_is_claimed_self_hosted(struct coresight_device *csdev) diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index 05f891ca6b5c..cc7ff1e36ef4 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -35,6 +35,7 @@ extern const struct device_type coresight_dev_type[]; * Coresight device CLAIM protocol. * See PSCI - ARM DEN 0022D, Section: 6.8.1 Debug and Trace save and restore. */ +#define CORESIGHT_CLAIM_MASK GENMASK(1, 0) #define CORESIGHT_CLAIM_SELF_HOSTED BIT(1) #define TIMEOUT_US 100 |