[PATCH V2 03/30] coresight: etm3x: unlocking tracers in default arch init
From: mathieu.poirier@linaro.org (Mathieu Poirier)
Date: 2015-10-18 18:33:41
Also in:
lkml
Subsystem:
arm/coresight framework and drivers, hardware tracing facilities, the rest · Maintainers:
Suzuki K Poulose, Alexander Shishkin, Linus Torvalds
Calling function 'smp_call_function_single()' to unlock a tracer and calling it right after to perform the default initialisation doesn't make sense. Moving 'etm_os_unlock()' just before making the default initialisation results in the same outcome while saving one call to 'smp_call_function_single()'. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> --- drivers/hwtracing/coresight/coresight-etm3x.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 2a1950d0753d..737b6164f4a5 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c@@ -47,11 +47,11 @@ static struct etm_drvdata *etmdrvdata[NR_CPUS]; * and OS lock must be unlocked before any memory mapped access on such * processors, otherwise memory mapped reads/writes will be invalid. */ -static void etm_os_unlock(void *info) +static void etm_os_unlock(struct etm_drvdata *drvdata) { - struct etm_drvdata *drvdata = (struct etm_drvdata *)info; /* Writing any value to ETMOSLAR unlocks the trace registers */ etm_writel(drvdata, 0x0, ETMOSLAR); + drvdata->os_unlock = true; isb(); }
@@ -478,6 +478,9 @@ static void etm_init_arch_data(void *info) u32 etmccr; struct etm_drvdata *drvdata = info; + /* Make sure all registers are accessible */ + etm_os_unlock(drvdata); + CS_UNLOCK(drvdata->base); /* First dummy read */
@@ -602,9 +605,6 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id) get_online_cpus(); etmdrvdata[drvdata->cpu] = drvdata; - if (!smp_call_function_single(drvdata->cpu, etm_os_unlock, drvdata, 1)) - drvdata->os_unlock = true; - if (smp_call_function_single(drvdata->cpu, etm_init_arch_data, drvdata, 1)) dev_err(dev, "ETM arch init failed\n");
--
1.9.1