Add support for reporting errors back from the SMP cross function call for enabling ETM.
Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com --- Changes since v1: - Fix build break, missing ;. (Mathieu Poirier) --- drivers/hwtracing/coresight/coresight-etm3x.c | 42 ++++++++++++++++++--------- 1 file changed, 28 insertions(+), 14 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c index 9ce8fba..206c238 100644 --- a/drivers/hwtracing/coresight/coresight-etm3x.c +++ b/drivers/hwtracing/coresight/coresight-etm3x.c @@ -355,11 +355,10 @@ static int etm_parse_event_config(struct etm_drvdata *drvdata, return 0; }
-static void etm_enable_hw(void *info) +static int etm_enable_hw(struct etm_drvdata *drvdata) { int i; u32 etmcr; - struct etm_drvdata *drvdata = info; struct etm_config *config = &drvdata->config;
CS_UNLOCK(drvdata->base); @@ -421,6 +420,21 @@ static void etm_enable_hw(void *info) CS_LOCK(drvdata->base);
dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu); + return 0; +} + +struct etm_enable_arg { + struct etm_drvdata *drvdata; + int rc; +}; + +static void etm_enable_hw_smp_call(void *info) +{ + struct etm_enable_arg *arg = info; + + if (WARN_ON(!arg)) + return; + arg->rc = etm_enable_hw(arg->drvdata); }
static int etm_cpu_id(struct coresight_device *csdev) @@ -475,14 +489,13 @@ static int etm_enable_perf(struct coresight_device *csdev, /* Configure the tracer based on the session's specifics */ etm_parse_event_config(drvdata, event); /* And enable it */ - etm_enable_hw(drvdata); - - return 0; + return etm_enable_hw(drvdata); }
static int etm_enable_sysfs(struct coresight_device *csdev) { struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + struct etm_enable_arg arg = { 0 }; int ret;
spin_lock(&drvdata->spinlock); @@ -492,20 +505,21 @@ static int etm_enable_sysfs(struct coresight_device *csdev) * hw configuration will take place on the local CPU during bring up. */ if (cpu_online(drvdata->cpu)) { + arg.drvdata = drvdata; ret = smp_call_function_single(drvdata->cpu, - etm_enable_hw, drvdata, 1); - if (ret) - goto err; + etm_enable_hw_smp_call, &arg, 1); + if (!ret) + ret = arg.rc; + if (!ret) + drvdata->sticky_enable = true; + } else { + ret = -ENODEV; }
- drvdata->sticky_enable = true; spin_unlock(&drvdata->spinlock);
- dev_dbg(drvdata->dev, "ETM tracing enabled\n"); - return 0; - -err: - spin_unlock(&drvdata->spinlock); + if (!ret) + dev_dbg(drvdata->dev, "ETM tracing enabled\n"); return ret; }