[PATCH 03/13] coresight: tmc-etb/etf: Prepare to handle errors enabling

Suzuki K Poulose
2018-08-06T13:44:20Z

Prepare to handle errors in enabling the hardware and
report it back to the core driver.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
drivers/hwtracing/coresight/coresight-tmc-etf.c | 71 +++++++++++++++----------
1 file changed, 44 insertions(+), 27 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 4156c95..ceb4b30 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -15,7 +15,7 @@
static int tmc_set_etf_buffer(struct coresight_device *csdev,
struct perf_output_handle *handle);

-static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
{
CS_UNLOCK(drvdata->base);

@@ -34,6 +34,12 @@ static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
CS_LOCK(drvdata->base);
}

+static int tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
+{
+ __tmc_etb_enable_hw(drvdata);
+ return 0;
+}
+
static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
{
char *bufp;
@@ -76,7 +82,7 @@ static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
CS_LOCK(drvdata->base);
}

-static void tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
{
CS_UNLOCK(drvdata->base);

@@ -92,6 +98,12 @@ static void tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
CS_LOCK(drvdata->base);
}

+static int tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
+{
+ __tmc_etf_enable_hw(drvdata);
+ return 0;
+}
+
static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
{
CS_UNLOCK(drvdata->base);
@@ -174,8 +186,12 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
drvdata->buf = buf;
}

- drvdata->mode = CS_MODE_SYSFS;
- tmc_etb_enable_hw(drvdata);
+ ret = tmc_etb_enable_hw(drvdata);
+ if (!ret)
+ drvdata->mode = CS_MODE_SYSFS;
+ else
+ /* Free up the buffer if we failed to enable */
+ used = false;
out:
spin_unlock_irqrestore(&drvdata->spinlock, flags);

@@ -194,27 +210,25 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
struct perf_output_handle *handle = data;

spin_lock_irqsave(&drvdata->spinlock, flags);
- if (drvdata->reading) {
+ do {
ret = -EINVAL;
- goto out;
- }
+ if (drvdata->reading)
+ break;
+ /*
+ * In Perf mode there can be only one writer per sink. There
+ * is also no need to continue if the ETB/ETF is already
+ * operated from sysFS.
+ */
+ if (drvdata->mode != CS_MODE_DISABLED)
+ break;

- /*
- * In Perf mode there can be only one writer per sink. There
- * is also no need to continue if the ETB/ETR is already operated
- * from sysFS.
- */
- if (drvdata->mode != CS_MODE_DISABLED) {
- ret = -EINVAL;
- goto out;
- }
-
- ret = tmc_set_etf_buffer(csdev, handle);
- if (!ret) {
- drvdata->mode = CS_MODE_PERF;
- tmc_etb_enable_hw(drvdata);
- }
-out:
+ ret = tmc_set_etf_buffer(csdev, handle);
+ if (ret)
+ break;
+ ret = tmc_etb_enable_hw(drvdata);
+ if (!ret)
+ drvdata->mode = CS_MODE_PERF;
+ } while (0);
spin_unlock_irqrestore(&drvdata->spinlock, flags);

return ret;
@@ -271,6 +285,7 @@ static void tmc_disable_etf_sink(struct coresight_device *csdev)
static int tmc_enable_etf_link(struct coresight_device *csdev,
int inport, int outport)
{
+ int ret;
unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);

@@ -280,11 +295,13 @@ static int tmc_enable_etf_link(struct coresight_device *csdev,
return -EBUSY;
}

- tmc_etf_enable_hw(drvdata);
- drvdata->mode = CS_MODE_SYSFS;
+ ret = tmc_etf_enable_hw(drvdata);
+ if (!ret)
+ drvdata->mode = CS_MODE_SYSFS;
spin_unlock_irqrestore(&drvdata->spinlock, flags);

- dev_dbg(drvdata->dev, "TMC-ETF enabled\n");
+ if (!ret)
+ dev_dbg(drvdata->dev, "TMC-ETF enabled\n");
return 0;
}

@@ -579,7 +596,7 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
* can't be NULL.
*/
memset(drvdata->buf, 0, drvdata->size);
- tmc_etb_enable_hw(drvdata);
+ __tmc_etb_enable_hw(drvdata);
} else {
/*
* The ETB/ETF is not tracing and the buffer was just read.
--
2.7.4