Re: [PATCH] media: cedrus: Implement runtime PM

Paul Kocialkowski
2020-04-08T11:37:30Z

Hi,

On Tue 07 Apr 20, 20:02, Samuel Holland wrote:
> This allows the VE clocks and PLL_VE to be disabled most of the time.
>
> Since the device is stateless, each frame gets a separate runtime PM
> reference. Enable autosuspend so the PM callbacks are not run before and
> after every frame.

Looks good, thanks for the contribution :)

Acked-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

Cheers,

Paul

> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
>
> I tested this with v4l2-request-test. I don't have the setup to do
> anything more complicated at the moment.
>
> ---
> drivers/staging/media/sunxi/cedrus/cedrus.c | 7 ++
> .../staging/media/sunxi/cedrus/cedrus_hw.c | 115 ++++++++++++------
> .../staging/media/sunxi/cedrus/cedrus_hw.h | 3 +
> 3 files changed, 88 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c
> index 3fad5edccd17..9aa1fc8a6c26 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
> @@ -16,6 +16,7 @@
> #include <linux/platform_device.h>
> #include <linux/module.h>
> #include <linux/of.h>
> +#include <linux/pm.h>
>
> #include <media/v4l2-device.h>
> #include <media/v4l2-ioctl.h>
> @@ -474,6 +475,11 @@ static int cedrus_remove(struct platform_device *pdev)
> return 0;
> }
>
> +static const struct dev_pm_ops cedrus_dev_pm_ops = {
> + SET_RUNTIME_PM_OPS(cedrus_hw_suspend,
> + cedrus_hw_resume, NULL)
> +};
> +
> static const struct cedrus_variant sun4i_a10_cedrus_variant = {
> .mod_rate = 320000000,
> };
> @@ -559,6 +565,7 @@ static struct platform_driver cedrus_driver = {
> .driver = {
> .name = CEDRUS_NAME,
> .of_match_table = of_match_ptr(cedrus_dt_match),
> + .pm = &cedrus_dev_pm_ops,
> },
> };
> module_platform_driver(cedrus_driver);
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> index daf5f244f93b..b84814d5afe4 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
> @@ -19,6 +19,7 @@
> #include <linux/dma-mapping.h>
> #include <linux/interrupt.h>
> #include <linux/clk.h>
> +#include <linux/pm_runtime.h>
> #include <linux/regmap.h>
> #include <linux/reset.h>
> #include <linux/soc/sunxi/sunxi_sram.h>
> @@ -63,6 +64,8 @@ int cedrus_engine_enable(struct cedrus_ctx *ctx, enum cedrus_codec codec)
> if (ctx->src_fmt.width > 2048)
> reg |= VE_MODE_PIC_WIDTH_MORE_2048;
>
> + pm_runtime_get_sync(ctx->dev->dev);
> +
> cedrus_write(ctx->dev, VE_MODE, reg);
>
> return 0;
> @@ -71,6 +74,9 @@ int cedrus_engine_enable(struct cedrus_ctx *ctx, enum cedrus_codec codec)
> void cedrus_engine_disable(struct cedrus_dev *dev)
> {
> cedrus_write(dev, VE_MODE, VE_MODE_DISABLED);
> +
> + pm_runtime_mark_last_busy(dev->dev);
> + pm_runtime_put_autosuspend(dev->dev);
> }
>
> void cedrus_dst_format_set(struct cedrus_dev *dev,
> @@ -134,12 +140,72 @@ static irqreturn_t cedrus_irq(int irq, void *data)
> else
> state = VB2_BUF_STATE_DONE;
>
> + cedrus_engine_disable(dev);
> +
> v4l2_m2m_buf_done_and_job_finish(ctx->dev->m2m_dev, ctx->fh.m2m_ctx,
> state);
>
> return IRQ_HANDLED;
> }
>
> +int cedrus_hw_resume(struct device *d)
> +{
> + struct cedrus_dev *dev = dev_get_drvdata(d);
> + int ret;
> +
> + ret = clk_prepare_enable(dev->ahb_clk);
> + if (ret) {
> + dev_err(dev->dev, "Failed to enable AHB clock\n");
> +
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(dev->mod_clk);
> + if (ret) {
> + dev_err(dev->dev, "Failed to enable MOD clock\n");
> +
> + goto err_ahb_clk;
> + }
> +
> + ret = clk_prepare_enable(dev->ram_clk);
> + if (ret) {
> + dev_err(dev->dev, "Failed to enable RAM clock\n");
> +
> + goto err_mod_clk;
> + }
> +
> + ret = reset_control_reset(dev->rstc);
> + if (ret) {
> + dev_err(dev->dev, "Failed to apply reset\n");
> +
> + goto err_ram_clk;
> + }
> +
> + return 0;
> +
> +err_ram_clk:
> + clk_disable_unprepare(dev->ram_clk);
> +err_mod_clk:
> + clk_disable_unprepare(dev->mod_clk);
> +err_ahb_clk:
> + clk_disable_unprepare(dev->ahb_clk);
> +
> + return ret;
> +}
> +
> +int cedrus_hw_suspend(struct device *d)
> +{
> + struct cedrus_dev *dev = dev_get_drvdata(d);
> +
> + reset_control_assert(dev->rstc);
> +
> + clk_disable_unprepare(dev->ram_clk);
> + clk_disable_unprepare(dev->mod_clk);
> + clk_disable_unprepare(dev->ahb_clk);
> +
> + return 0;
> +}
> +
> int cedrus_hw_probe(struct cedrus_dev *dev)
> {
> const struct cedrus_variant *variant;
> @@ -236,42 +302,19 @@ int cedrus_hw_probe(struct cedrus_dev *dev)
> goto err_sram;
> }
>
> - ret = clk_prepare_enable(dev->ahb_clk);
> - if (ret) {
> - dev_err(dev->dev, "Failed to enable AHB clock\n");
> -
> - goto err_sram;
> - }
> -
> - ret = clk_prepare_enable(dev->mod_clk);
> - if (ret) {
> - dev_err(dev->dev, "Failed to enable MOD clock\n");
> -
> - goto err_ahb_clk;
> - }
> -
> - ret = clk_prepare_enable(dev->ram_clk);
> - if (ret) {
> - dev_err(dev->dev, "Failed to enable RAM clock\n");
> -
> - goto err_mod_clk;
> - }
> -
> - ret = reset_control_reset(dev->rstc);
> - if (ret) {
> - dev_err(dev->dev, "Failed to apply reset\n");
> -
> - goto err_ram_clk;
> + pm_runtime_set_autosuspend_delay(dev->dev, 1000);
> + pm_runtime_use_autosuspend(dev->dev);
> + pm_runtime_enable(dev->dev);
> + if (!pm_runtime_enabled(dev->dev)) {
> + ret = cedrus_hw_resume(dev->dev);
> + if (ret)
> + goto err_pm;
> }
>
> return 0;
>
> -err_ram_clk:
> - clk_disable_unprepare(dev->ram_clk);
> -err_mod_clk:
> - clk_disable_unprepare(dev->mod_clk);
> -err_ahb_clk:
> - clk_disable_unprepare(dev->ahb_clk);
> +err_pm:
> + pm_runtime_disable(dev->dev);
> err_sram:
> sunxi_sram_release(dev->dev);
> err_mem:
> @@ -282,11 +325,9 @@ int cedrus_hw_probe(struct cedrus_dev *dev)
>
> void cedrus_hw_remove(struct cedrus_dev *dev)
> {
> - reset_control_assert(dev->rstc);
> -
> - clk_disable_unprepare(dev->ram_clk);
> - clk_disable_unprepare(dev->mod_clk);
> - clk_disable_unprepare(dev->ahb_clk);
> + pm_runtime_disable(dev->dev);
> + if (!pm_runtime_status_suspended(dev->dev))
> + cedrus_hw_suspend(dev->dev);
>
> sunxi_sram_release(dev->dev);
>
> diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_hw.h b/drivers/staging/media/sunxi/cedrus/cedrus_hw.h
> index 604ff932fbf5..17822b470a1e 100644
> --- a/drivers/staging/media/sunxi/cedrus/cedrus_hw.h
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus_hw.h
> @@ -22,6 +22,9 @@ void cedrus_engine_disable(struct cedrus_dev *dev);
> void cedrus_dst_format_set(struct cedrus_dev *dev,
> struct v4l2_pix_format *fmt);
>
> +int cedrus_hw_resume(struct device *dev);
> +int cedrus_hw_suspend(struct device *dev);
> +
> int cedrus_hw_probe(struct cedrus_dev *dev);
> void cedrus_hw_remove(struct cedrus_dev *dev);
>
> --
> 2.24.1
>