From e2a1551a881f27d1914f182e06b423cc242b43b6 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Thu, 20 Sep 2018 13:18:08 -0600 Subject: [PATCH] coresight: etm3: Add support for handling errors Add support for reporting errors back from the SMP cross function call for enabling ETM. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- 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 9ce8fba20b0f..206c2381a11a 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; } -- 2.39.5