Messages in this thread Patch in this message | | | From | Mathieu Poirier <> | Subject | [PATCH] coresight: add PM runtime calls to coresight_simple_func() | Date | Fri, 17 Jun 2016 11:41:47 -0600 |
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It is mandatory to enable a coresight block's power domain before trying to access management registers. Otherwise the transaction simply stalls, leading to a system hang.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> --- drivers/hwtracing/coresight/coresight-priv.h | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index ad975c58080d..b047241e7496 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -16,6 +16,7 @@ #include <linux/bitops.h> #include <linux/io.h> #include <linux/coresight.h> +#include <linux/pm_runtime.h> /* * Coresight management registers (0xf00-0xfcc) @@ -42,8 +43,10 @@ static ssize_t name##_show(struct device *_dev, \ struct device_attribute *attr, char *buf) \ { \ type *drvdata = dev_get_drvdata(_dev->parent); \ + pm_runtime_get_sync(_dev->parent); \ return scnprintf(buf, PAGE_SIZE, "0x%x\n", \ readl_relaxed(drvdata->base + offset)); \ + pm_runtime_put_sync(_dev->parent); \ } \ static DEVICE_ATTR_RO(name) -- 2.5.0
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