linux-stable.git/drivers/hwtracing, branch v6.8

coresight: ultrasoc-smb: Use guards to cleanup

2023-11-21T11:21:59+00:00

Use guards to reduce gotos and simplify control flow.

Signed-off-by: Junhao He 
Reviewed-by: James Clark 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231114133346.30489-5-hejunhao3@huawei.com

coresight: ultrasoc-smb: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-14-u.kleine-koenig@pengutronix.de

coresight: trbe: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-13-u.kleine-koenig@pengutronix.de

coresight: replicator: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-12-u.kleine-koenig@pengutronix.de

coresight: funnel: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-11-u.kleine-koenig@pengutronix.de

coresight: etm4x: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-10-u.kleine-koenig@pengutronix.de

coresight: dummy: Convert to platform remove callback returning void

2023-11-16T18:17:23+00:00

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Reviewed-by: James Clark 
Signed-off-by: Uwe Kleine-König 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231116173301.708873-9-u.kleine-koenig@pengutronix.de

coresight: etm4x: Fix width of CCITMIN field

2023-11-16T11:40:59+00:00

CCITMIN is a 12 bit field and doesn't fit in a u8, so extend it to u16.
This probably wasn't an issue previously because values higher than 255
never occurred.

But since commit 4aff040bcc8d ("coresight: etm: Override TRCIDR3.CCITMIN
on errata affected cpus"), a comparison with 256 was done to enable the
errata, generating the following W=1 build error:

  coresight-etm4x-core.c:1188:24: error: result of comparison of
  constant 256 with expression of type 'u8' (aka 'unsigned char') is
  always false [-Werror,-Wtautological-constant-out-of-range-compare]

   if (drvdata->ccitmin == 256)

Cc: stable@vger.kernel.org
Fixes: 2e1cdfe184b5 ("coresight-etm4x: Adding CoreSight ETM4x driver")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202310302043.as36UFED-lkp@intel.com/
Reviewed-by: Mike Leach 
Signed-off-by: James Clark 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231101115206.70810-1-james.clark@arm.com

coresight-tpdm: Correct the property name of MSR number

2023-11-16T11:36:38+00:00

Correct the property name of the DSB MSR number that needs to be
read in TPDM driver. The right property name is
"qcom,dsb-msrs-num".

Fixes: 350ba15ae187 ("coresight-tpdm: Add nodes for dsb msr support")
Signed-off-by: Tao Zhang 
[ Fix checkpatch failure in the commit description ]
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/1698128353-31157-1-git-send-email-quic_taozha@quicinc.com

hwtracing: hisi_ptt: Optimize the trace data committing

2023-11-16T11:36:33+00:00

In the current implementation, there're 4*4MiB trace buffer and hardware
will fill the buffer one by one. The driver will get notified if one
buffer is full and then copy data to the AUX buffer. If there's no
enough room for the next trace buffer, we'll commit the AUX buffer to
the perf core and try to apply a new one. In a typical configuration
the AUX buffer will be 16MiB, so we'll commit the data after the whole
AUX buffer is occupied. Then the driver cannot apply a new AUX buffer
immediately until the committed data is consumed by userspace and then
there's room in the AUX buffer again.

This patch tries to optimize this by commit the data after one single
trace buffer is filled. Since there's still room in the AUX buffer,
driver can apply a new one without failure and don't need to wait for
the userspace to consume the data.

Signed-off-by: Yicong Yang 
Acked-by: Jonathan Cameron 
Signed-off-by: Suzuki K Poulose 
Link: https://lore.kernel.org/r/20231010084731.30450-4-yangyicong@huawei.com