From: Suzuki K Poulose <suzuki.poulose@arm.com>
Date: Wed, 28 Oct 2020 22:09:24 +0000
Subject: coresight: etm4x: Handle TRCVIPCSSCTLR accesses

Git-commit: 60c519c5d3629c21ba356782434d5b612d312de4
Patch-mainline: v5.11-rc1
References: jsc#SLE-13629,jsc#SLE-14776

TRCVIPCSSCTLR is not present if the TRCIDR4.NUMPC > 0. Thus we
should only access the register if it is present, preventing
any undesired behavior.

Cc: stable@vger.kernel.org
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/hwtracing/coresight/coresight-etm4x-core.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 28dd278f6d47..d78a37b6592c 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -141,8 +141,9 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 	writel_relaxed(config->viiectlr, drvdata->base + TRCVIIECTLR);
 	writel_relaxed(config->vissctlr,
 		       drvdata->base + TRCVISSCTLR);
-	writel_relaxed(config->vipcssctlr,
-		       drvdata->base + TRCVIPCSSCTLR);
+	if (drvdata->nr_pe_cmp)
+		writel_relaxed(config->vipcssctlr,
+			       drvdata->base + TRCVIPCSSCTLR);
 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
 		writel_relaxed(config->seq_ctrl[i],
 			       drvdata->base + TRCSEQEVRn(i));
@@ -1202,7 +1203,8 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
 	state->trcvictlr = readl(drvdata->base + TRCVICTLR);
 	state->trcviiectlr = readl(drvdata->base + TRCVIIECTLR);
 	state->trcvissctlr = readl(drvdata->base + TRCVISSCTLR);
-	state->trcvipcssctlr = readl(drvdata->base + TRCVIPCSSCTLR);
+	if (drvdata->nr_pe_cmp)
+		state->trcvipcssctlr = readl(drvdata->base + TRCVIPCSSCTLR);
 	state->trcvdctlr = readl(drvdata->base + TRCVDCTLR);
 	state->trcvdsacctlr = readl(drvdata->base + TRCVDSACCTLR);
 	state->trcvdarcctlr = readl(drvdata->base + TRCVDARCCTLR);
@@ -1310,7 +1312,8 @@ static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
 	writel_relaxed(state->trcvictlr, drvdata->base + TRCVICTLR);
 	writel_relaxed(state->trcviiectlr, drvdata->base + TRCVIIECTLR);
 	writel_relaxed(state->trcvissctlr, drvdata->base + TRCVISSCTLR);
-	writel_relaxed(state->trcvipcssctlr, drvdata->base + TRCVIPCSSCTLR);
+	if (drvdata->nr_pe_cmp)
+		writel_relaxed(state->trcvipcssctlr, drvdata->base + TRCVIPCSSCTLR);
 	writel_relaxed(state->trcvdctlr, drvdata->base + TRCVDCTLR);
 	writel_relaxed(state->trcvdsacctlr, drvdata->base + TRCVDSACCTLR);
 	writel_relaxed(state->trcvdarcctlr, drvdata->base + TRCVDARCCTLR);
-- 
2.26.2