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coresight: etm4x: Fix timestamp bit field handling

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Timestamps in the trace data appear as all zeros on recent kernels,
although the feature works correctly on old kernels (e.g., v6.12).

Since commit c382ee674c ("arm64/sysreg/tools: Move TRFCR definitions
to sysreg"), the TRFCR_ELx_TS_{VIRTUAL|GUEST_PHYSICAL|PHYSICAL} macros
were updated to remove the bit shift. As a result, the driver no longer
shifts bits when operates the timestamp field.

Fix this by using the FIELD_PREP() and FIELD_GET() helpers.

Reported-by: Tamas Zsoldos <tamas.zsoldos@arm.com>
Fixes: c382ee674c ("arm64/sysreg/tools: Move TRFCR definitions to sysreg")
Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250519174945.2245271-2-leo.yan@arm.com
This commit is contained in:
Leo Yan
2025-05-19 18:49:44 +01:00
committed by Suzuki K Poulose
parent d23bc38e8a
commit ee811bc733
2 changed files with 3 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/hwtracing/coresight/coresight-etm4x-core.c
View File

@@ -1237,7 +1237,7 @@ static void cpu_detect_trace_filtering(struct etmv4_drvdata *drvdata)
* tracing at the kernel EL and EL0, forcing to use the
* virtual time as the timestamp.
*/
trfcr = (TRFCR_EL1_TS_VIRTUAL |
trfcr = (FIELD_PREP(TRFCR_EL1_TS_MASK, TRFCR_EL1_TS_VIRTUAL) |
TRFCR_EL1_ExTRE |
TRFCR_EL1_E0TRE);

4
drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
View File

@@ -2320,11 +2320,11 @@ static ssize_t ts_source_show(struct device *dev,
goto out;
}
switch (drvdata->trfcr & TRFCR_EL1_TS_MASK) {
val = FIELD_GET(TRFCR_EL1_TS_MASK, drvdata->trfcr);
switch (val) {
case TRFCR_EL1_TS_VIRTUAL:
case TRFCR_EL1_TS_GUEST_PHYSICAL:
case TRFCR_EL1_TS_PHYSICAL:
val = FIELD_GET(TRFCR_EL1_TS_MASK, drvdata->trfcr);
break;
default:
val = -1;