[PATCH 5.8 236/633] coresight: etm4x: Fix issues on trcseqevr access

Greg Kroah-Hartman
2020-10-27T15:01:59Z

From: Jonathan Zhou <jonathan.zhouwen@huawei.com>

[ Upstream commit 4cd83037cd957ad97756055355ab4ee63f259380 ]

The TRCSEQEVR(3) is reserved, using '@nrseqstate - 1' instead to avoid
accessing the reserved register.

Fixes: f188b5e76aae ("coresight: etm4x: Save/restore state across CPU low power states")
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Jonathan Zhou <jonathan.zhouwen@huawei.com>
[Fixed capital letter in title]
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200916191737.4001561-12-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/hwtracing/coresight/coresight-etm4x.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 7a247273b7e0a..d6395aeffd99d 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1189,7 +1189,7 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
state->trcvdsacctlr = readl(drvdata->base + TRCVDSACCTLR);
state->trcvdarcctlr = readl(drvdata->base + TRCVDARCCTLR);

- for (i = 0; i < drvdata->nrseqstate; i++)
+ for (i = 0; i < drvdata->nrseqstate - 1; i++)
state->trcseqevr[i] = readl(drvdata->base + TRCSEQEVRn(i));

state->trcseqrstevr = readl(drvdata->base + TRCSEQRSTEVR);
@@ -1294,7 +1294,7 @@ static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
writel_relaxed(state->trcvdsacctlr, drvdata->base + TRCVDSACCTLR);
writel_relaxed(state->trcvdarcctlr, drvdata->base + TRCVDARCCTLR);

- for (i = 0; i < drvdata->nrseqstate; i++)
+ for (i = 0; i < drvdata->nrseqstate - 1; i++)
writel_relaxed(state->trcseqevr[i],
drvdata->base + TRCSEQEVRn(i));

--
2.25.1