On Thu, Jul 30, 2020 at 03:46:26AM +0200, Paul Cercueil wrote:
> Instead of keeping the IPU clock enabled constantly, enable and disable
> it on demand, when the IPU plane is used.
This explains what the patch does - but fails to mention why.
Could you please add the why part too.
With the chagelog updated:
Reviewed-by: Sam Ravnborg <s...@ravnborg.org>
Sam
>
> Signed-off-by: Paul Cercueil <p...@crapouillou.net>
> ---
> drivers/gpu/drm/ingenic/ingenic-ipu.c | 23 ++++++++++++++++++++---
> 1 file changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/ingenic/ingenic-ipu.c
> b/drivers/gpu/drm/ingenic/ingenic-ipu.c
> index f4f0abcd6692..17e682cf1eba 100644
> --- a/drivers/gpu/drm/ingenic/ingenic-ipu.c
> +++ b/drivers/gpu/drm/ingenic/ingenic-ipu.c
> @@ -49,6 +49,7 @@ struct ingenic_ipu {
> struct regmap *map;
> struct clk *clk;
> const struct soc_info *soc_info;
> + bool clk_enabled;
>
> unsigned int num_w, num_h, denom_w, denom_h;
>
> @@ -288,12 +289,23 @@ static void ingenic_ipu_plane_atomic_update(struct
> drm_plane *plane,
> const struct drm_format_info *finfo;
> u32 ctrl, stride = 0, coef_index = 0, format = 0;
> bool needs_modeset, upscaling_w, upscaling_h;
> + int err;
>
> if (!state || !state->fb)
> return;
>
> finfo = drm_format_info(state->fb->format->format);
>
> + if (!ipu->clk_enabled) {
> + err = clk_enable(ipu->clk);
> + if (err) {
> + dev_err(ipu->dev, "Unable to enable clock: %d\n", err);
> + return;
> + }
> +
> + ipu->clk_enabled = true;
> + }
> +
> /* Reset all the registers if needed */
> needs_modeset = drm_atomic_crtc_needs_modeset(state->crtc->state);
> if (needs_modeset) {
> @@ -578,6 +590,11 @@ static void ingenic_ipu_plane_atomic_disable(struct
> drm_plane *plane,
> regmap_clear_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_CHIP_EN);
>
> ingenic_drm_plane_disable(ipu->master, plane);
> +
> + if (ipu->clk_enabled) {
> + clk_disable(ipu->clk);
> + ipu->clk_enabled = false;
> + }
> }
>
> static const struct drm_plane_helper_funcs ingenic_ipu_plane_helper_funcs = {
> @@ -761,9 +778,9 @@ static int ingenic_ipu_bind(struct device *dev, struct
> device *master, void *d)
> drm_object_attach_property(&plane->base, ipu->sharpness_prop,
> ipu->sharpness);
>
> - err = clk_prepare_enable(ipu->clk);
> + err = clk_prepare(ipu->clk);
> if (err) {
> - dev_err(dev, "Unable to enable clock\n");
> + dev_err(dev, "Unable to prepare clock\n");
> return err;
> }
>
> @@ -775,7 +792,7 @@ static void ingenic_ipu_unbind(struct device *dev,
> {
> struct ingenic_ipu *ipu = dev_get_drvdata(dev);
>
> - clk_disable_unprepare(ipu->clk);
> + clk_unprepare(ipu->clk);
> }
>
> static const struct component_ops ingenic_ipu_ops = {
> --
> 2.27.0
