linux-kernel - [PATCH v2 10/14] coresight: etmx: Claim devices before use

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Date:   Thu,  6 Sep 2018 10:08:31 +0100
From:   Suzuki K Poulose <suzuki.poulose@....com>
To:     linux-arm-kernel@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org, mathieu.poirier@...aro.org,
        coresight@...ts.linaro.org, suzuki.poulose@....com,
        robert.walker@....com, al.grant@....com
Subject: [PATCH v2 10/14] coresight: etmx: Claim devices before use

Use the CLAIM tags to grab the device for self-hosted usage.

Cc: Mathieu Poirier <mathieu.poirier@...aro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@....com>
---
 drivers/hwtracing/coresight/coresight-etm3x.c | 16 +++++++++++++---
 drivers/hwtracing/coresight/coresight-etm4x.c | 14 +++++++++++---
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 206c238..fd5c4cc 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -357,7 +357,7 @@ static int etm_parse_event_config(struct etm_drvdata *drvdata,
 
 static int etm_enable_hw(struct etm_drvdata *drvdata)
 {
-	int i;
+	int i, rc;
 	u32 etmcr;
 	struct etm_config *config = &drvdata->config;
 
@@ -369,6 +369,9 @@ static int etm_enable_hw(struct etm_drvdata *drvdata)
 	etm_set_pwrup(drvdata);
 	/* Make sure all registers are accessible */
 	etm_os_unlock(drvdata);
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		goto done;
 
 	etm_set_prog(drvdata);
 
@@ -417,10 +420,15 @@ static int etm_enable_hw(struct etm_drvdata *drvdata)
 	etm_writel(drvdata, 0x0, ETMVMIDCVR);
 
 	etm_clr_prog(drvdata);
+
+done:
+	if (rc)
+		etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
-	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
-	return 0;
+	dev_dbg(drvdata->dev, "cpu: %d enable smp call done: %d\n",
+		drvdata->cpu, rc);
+	return rc;
 }
 
 struct etm_enable_arg {
@@ -569,6 +577,8 @@ static void etm_disable_hw(void *info)
 	for (i = 0; i < drvdata->nr_cntr; i++)
 		config->cntr_val[i] = etm_readl(drvdata, ETMCNTVRn(i));
 
+	coresight_disclaim_device_unlocked(drvdata->base);
+
 	etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 4f9e6bb..ac311e5 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -84,13 +84,17 @@ struct etm4_enable_arg {
 
 static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 {
-	int i;
+	int i, rc;
 	struct etmv4_config *config = &drvdata->config;
 
 	CS_UNLOCK(drvdata->base);
 
 	etm4_os_unlock(drvdata);
 
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		goto done;
+
 	/* Disable the trace unit before programming trace registers */
 	writel_relaxed(0, drvdata->base + TRCPRGCTLR);
 
@@ -178,10 +182,12 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 		dev_err(drvdata->dev,
 			"timeout while waiting for Idle Trace Status\n");
 
+done:
 	CS_LOCK(drvdata->base);
 
-	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
-	return 0;
+	dev_dbg(drvdata->dev, "cpu: %d enable smp call done: %d\n",
+		drvdata->cpu, rc);
+	return rc;
 }
 
 static void etm4_enable_hw_smp_call(void *info)
@@ -341,6 +347,8 @@ static void etm4_disable_hw(void *info)
 	isb();
 	writel_relaxed(control, drvdata->base + TRCPRGCTLR);
 
+	coresight_disclaim_device_unlocked(drvdata->base);
+
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d disable smp call done\n", drvdata->cpu);
-- 
2.7.4