From: Alexander Shishkin alexander.shishkin@linux.intel.com
stable inclusion from linux-4.19.198 commit c79fef7357e5930648d7d5991bdfedaca3eb89ad
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[ Upstream commit ab1afed701d2db7eb35c1a2526a29067a38e93d1 ]
Some devices don't drain their pipelines if we don't make sure that the corresponding output port is in reset before programming it for a new trace capture, resulting in bits of old trace appearing in the new trace capture. Fix that by explicitly making sure the reset is asserted before programming new trace capture.
Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Signed-off-by: Alexander Shishkin alexander.shishkin@linux.intel.com Link: https://lore.kernel.org/r/20210621151246.31891-5-alexander.shishkin@linux.in... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/hwtracing/intel_th/core.c | 17 +++++++++++++++++ drivers/hwtracing/intel_th/gth.c | 16 ++++++++++++++++ drivers/hwtracing/intel_th/intel_th.h | 3 +++ 3 files changed, 36 insertions(+)
diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c index 6c723b57dfc07..be2f02e35067f 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -215,6 +215,22 @@ static ssize_t port_show(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR_RO(port);
+static void intel_th_trace_prepare(struct intel_th_device *thdev) +{ + struct intel_th_device *hub = to_intel_th_hub(thdev); + struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver); + + if (hub->type != INTEL_TH_SWITCH) + return; + + if (thdev->type != INTEL_TH_OUTPUT) + return; + + pm_runtime_get_sync(&thdev->dev); + hubdrv->prepare(hub, &thdev->output); + pm_runtime_put(&thdev->dev); +} + static int intel_th_output_activate(struct intel_th_device *thdev) { struct intel_th_driver *thdrv = @@ -235,6 +251,7 @@ static int intel_th_output_activate(struct intel_th_device *thdev) if (ret) goto fail_put;
+ intel_th_trace_prepare(thdev); if (thdrv->activate) ret = thdrv->activate(thdev); else diff --git a/drivers/hwtracing/intel_th/gth.c b/drivers/hwtracing/intel_th/gth.c index 5041fe7fee9ed..ef2751556fd77 100644 --- a/drivers/hwtracing/intel_th/gth.c +++ b/drivers/hwtracing/intel_th/gth.c @@ -513,6 +513,21 @@ static void gth_tscu_resync(struct gth_device *gth) iowrite32(reg, gth->base + REG_TSCU_TSUCTRL); }
+static void intel_th_gth_prepare(struct intel_th_device *thdev, + struct intel_th_output *output) +{ + struct gth_device *gth = dev_get_drvdata(&thdev->dev); + int count; + + /* + * Wait until the output port is in reset before we start + * programming it. + */ + for (count = GTH_PLE_WAITLOOP_DEPTH; + count && !(gth_output_get(gth, output->port) & BIT(5)); count--) + cpu_relax(); +} + /** * intel_th_gth_enable() - enable tracing to an output device * @thdev: GTH device @@ -734,6 +749,7 @@ static struct intel_th_driver intel_th_gth_driver = { .assign = intel_th_gth_assign, .unassign = intel_th_gth_unassign, .set_output = intel_th_gth_set_output, + .prepare = intel_th_gth_prepare, .enable = intel_th_gth_enable, .disable = intel_th_gth_disable, .driver = { diff --git a/drivers/hwtracing/intel_th/intel_th.h b/drivers/hwtracing/intel_th/intel_th.h index 780206dc9012c..6b5473f3c16f0 100644 --- a/drivers/hwtracing/intel_th/intel_th.h +++ b/drivers/hwtracing/intel_th/intel_th.h @@ -134,6 +134,7 @@ intel_th_output_assigned(struct intel_th_device *thdev) * @remove: remove method * @assign: match a given output type device against available outputs * @unassign: deassociate an output type device from an output port + * @prepare: prepare output port for tracing * @enable: enable tracing for a given output device * @disable: disable tracing for a given output device * @irq: interrupt callback @@ -155,6 +156,8 @@ struct intel_th_driver { struct intel_th_device *othdev); void (*unassign)(struct intel_th_device *thdev, struct intel_th_device *othdev); + void (*prepare)(struct intel_th_device *thdev, + struct intel_th_output *output); void (*enable)(struct intel_th_device *thdev, struct intel_th_output *output); void (*disable)(struct intel_th_device *thdev,