diff mbox series

[v3,3/3] drm/v3d: Make sure the GPU is on when measuring clocks.

Message ID 20190220233658.986-3-eric@anholt.net (mailing list archive)
State New, archived
Headers show
Series [v3,1/3] drm/v3d: Add support for V3D v4.2. | expand

Commit Message

Eric Anholt Feb. 20, 2019, 11:36 p.m. UTC
You'll get garbage measurements if the registers always read back
0xdeadbeef

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/v3d/v3d_debugfs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Dave Emett March 8, 2019, 4:47 p.m. UTC | #1
On Wed, 20 Feb 2019 at 23:37, Eric Anholt <eric@anholt.net> wrote:
>
> You'll get garbage measurements if the registers always read back
> 0xdeadbeef
>
> Signed-off-by: Eric Anholt <eric@anholt.net>

Reviewed-by: Dave Emett <david.emett@broadcom.com>

> ---
>  drivers/gpu/drm/v3d/v3d_debugfs.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_debugfs.c b/drivers/gpu/drm/v3d/v3d_debugfs.c
> index eb2b2d2f8553..a24af2d2f574 100644
> --- a/drivers/gpu/drm/v3d/v3d_debugfs.c
> +++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
> @@ -187,6 +187,11 @@ static int v3d_measure_clock(struct seq_file *m, void *unused)
>         uint32_t cycles;
>         int core = 0;
>         int measure_ms = 1000;
> +       int ret;
> +
> +       ret = pm_runtime_get_sync(v3d->dev);
> +       if (ret < 0)
> +               return ret;
>
>         if (v3d->ver >= 40) {
>                 V3D_CORE_WRITE(core, V3D_V4_PCTR_0_SRC_0_3,
> @@ -210,6 +215,9 @@ static int v3d_measure_clock(struct seq_file *m, void *unused)
>                    cycles / (measure_ms * 1000),
>                    (cycles / (measure_ms * 100)) % 10);
>
> +       pm_runtime_mark_last_busy(v3d->dev);
> +       pm_runtime_put_autosuspend(v3d->dev);
> +
>         return 0;
>  }
>
> --
> 2.20.1
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/v3d/v3d_debugfs.c b/drivers/gpu/drm/v3d/v3d_debugfs.c
index eb2b2d2f8553..a24af2d2f574 100644
--- a/drivers/gpu/drm/v3d/v3d_debugfs.c
+++ b/drivers/gpu/drm/v3d/v3d_debugfs.c
@@ -187,6 +187,11 @@  static int v3d_measure_clock(struct seq_file *m, void *unused)
 	uint32_t cycles;
 	int core = 0;
 	int measure_ms = 1000;
+	int ret;
+
+	ret = pm_runtime_get_sync(v3d->dev);
+	if (ret < 0)
+		return ret;
 
 	if (v3d->ver >= 40) {
 		V3D_CORE_WRITE(core, V3D_V4_PCTR_0_SRC_0_3,
@@ -210,6 +215,9 @@  static int v3d_measure_clock(struct seq_file *m, void *unused)
 		   cycles / (measure_ms * 1000),
 		   (cycles / (measure_ms * 100)) % 10);
 
+	pm_runtime_mark_last_busy(v3d->dev);
+	pm_runtime_put_autosuspend(v3d->dev);
+
 	return 0;
 }