mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-05 03:00:13 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

coresight: Only check bottom two claim bits

Browse source 
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
This commit is contained in:
James Clark 2025-03-25 11:58:47 +00:00 committed by Suzuki K Poulose
parent fc7fed6f77
commit a4e65842e1
2 changed files with 3 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

3
drivers/hwtracing/coresight/coresight-core.c
View file

@ -131,7 +131,8 @@ coresight_find_out_connection(struct coresight_device *csdev,
static inline u32 coresight_read_claim_tags_unlocked(struct coresight_device *csdev) static inline u32 coresight_read_claim_tags_unlocked(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) static inline bool coresight_is_claimed_self_hosted(struct coresight_device *csdev)

1
drivers/hwtracing/coresight/coresight-priv.h
View file

@ -35,6 +35,7 @@ extern const struct device_type coresight_dev_type[];
* Coresight device CLAIM protocol. * Coresight device CLAIM protocol.
* See PSCI - ARM DEN 0022D, Section: 6.8.1 Debug and Trace save and restore. * 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 CORESIGHT_CLAIM_SELF_HOSTED BIT(1)
#define TIMEOUT_US 100 #define TIMEOUT_US 100