6.9-stable review patch. If anyone has any objections, please let me know.
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From: Suzuki K Poulose suzuki.poulose@arm.com
[ Upstream commit d6fc00d0f640d6010b51054aa8b0fd191177dbc9 ]
Resource selector pair 0 is always implemented and reserved. We must not touch it, even during save/restore for CPU Idle. Rest of the driver is well behaved. Fix the offending ones.
Reported-by: Yabin Cui yabinc@google.com Fixes: f188b5e76aae ("coresight: etm4x: Save/restore state across CPU low power states") Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Tested-by: Yabin Cui yabinc@google.com Reviewed-by: Mike Leach mike.leach@linaro.org Link: https://lore.kernel.org/r/20240412142702.2882478-5-suzuki.poulose@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hwtracing/coresight/coresight-etm4x-core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 8643b77e50f41..a0bdfabddbc68 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -1758,7 +1758,8 @@ static int __etm4_cpu_save(struct etmv4_drvdata *drvdata) state->trccntvr[i] = etm4x_read32(csa, TRCCNTVRn(i)); }
- for (i = 0; i < drvdata->nr_resource * 2; i++) + /* Resource selector pair 0 is reserved */ + for (i = 2; i < drvdata->nr_resource * 2; i++) state->trcrsctlr[i] = etm4x_read32(csa, TRCRSCTLRn(i));
for (i = 0; i < drvdata->nr_ss_cmp; i++) { @@ -1889,7 +1890,8 @@ static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata) etm4x_relaxed_write32(csa, state->trccntvr[i], TRCCNTVRn(i)); }
- for (i = 0; i < drvdata->nr_resource * 2; i++) + /* Resource selector pair 0 is reserved */ + for (i = 2; i < drvdata->nr_resource * 2; i++) etm4x_relaxed_write32(csa, state->trcrsctlr[i], TRCRSCTLRn(i));
for (i = 0; i < drvdata->nr_ss_cmp; i++) {