(EXT) [PATCH] drm: mxsfb: Simplify LCDIF clock handling
Alexander Stein
alexander.stein at ew.tq-group.com
Thu Feb 10 08:11:27 UTC 2022
Hi Marek,
I like the overall idea. Thanks for the effort.
Am Sonntag, 6. Februar 2022, 19:55:55 CET schrieb Marek Vasut:
> The current clock handling in the LCDIF driver is a convoluted mess.
> Implement runtime PM ops which turn the clock ON and OFF and let the
> pm_runtime_get_sync()/pm_runtime_put_sync() calls in .atomic_enable
> and .atomic_disable callbacks turn the clock ON and OFF at the right
> time.
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Alexander Stein <alexander.stein at ew.tq-group.com>
> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Cc: Lucas Stach <l.stach at pengutronix.de>
> Cc: Peng Fan <peng.fan at nxp.com>
> Cc: Robby Cai <robby.cai at nxp.com>
> Cc: Sam Ravnborg <sam at ravnborg.org>
> Cc: Stefan Agner <stefan at agner.ch>
> ---
> drivers/gpu/drm/mxsfb/mxsfb_drv.c | 85 ++++++++++++++++++-------------
> drivers/gpu/drm/mxsfb/mxsfb_kms.c | 18 ++-----
> 2 files changed, 54 insertions(+), 49 deletions(-)
>
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> b/drivers/gpu/drm/mxsfb/mxsfb_drv.c index 375f26d4a4172..4ff3c6195dd0c
> 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> @@ -72,18 +72,6 @@ static const struct mxsfb_devdata mxsfb_devdata[] = {
> },
> };
>
> -void mxsfb_enable_axi_clk(struct mxsfb_drm_private *mxsfb)
> -{
> - if (mxsfb->clk_axi)
> - clk_prepare_enable(mxsfb->clk_axi);
> -}
> -
> -void mxsfb_disable_axi_clk(struct mxsfb_drm_private *mxsfb)
> -{
> - if (mxsfb->clk_axi)
> - clk_disable_unprepare(mxsfb->clk_axi);
> -}
> -
The declarations for mxsfb_enable_axi_clk() and mxsfb_disable_axi_clk() are
still in drivers/gpu/drm/mxsfb/mxsfb_drv.h. Please remove them as well.
You will then notice that they are still used at some places.
> static struct drm_framebuffer *
> mxsfb_fb_create(struct drm_device *dev, struct drm_file *file_priv,
> const struct drm_mode_fb_cmd2 *mode_cmd)
> @@ -224,33 +212,31 @@ static int mxsfb_load(struct drm_device *drm,
> if (IS_ERR(mxsfb->clk))
> return PTR_ERR(mxsfb->clk);
>
> - mxsfb->clk_axi = devm_clk_get(drm->dev, "axi");
> + mxsfb->clk_axi = devm_clk_get_optional(drm->dev, "axi");
> if (IS_ERR(mxsfb->clk_axi))
> - mxsfb->clk_axi = NULL;
> + return PTR_ERR(mxsfb->clk_axi);
>
> - mxsfb->clk_disp_axi = devm_clk_get(drm->dev, "disp_axi");
> + mxsfb->clk_disp_axi = devm_clk_get_optional(drm->dev, "disp_axi");
> if (IS_ERR(mxsfb->clk_disp_axi))
> - mxsfb->clk_disp_axi = NULL;
> + return PTR_ERR(mxsfb->clk_disp_axi);
>
> ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
> if (ret)
> return ret;
>
> - pm_runtime_enable(drm->dev);
> -
> /* Modeset init */
> drm_mode_config_init(drm);
>
> ret = mxsfb_kms_init(mxsfb);
> if (ret < 0) {
> dev_err(drm->dev, "Failed to initialize KMS
pipeline\n");
> - goto err_vblank;
> + return ret;
> }
>
> ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
> if (ret < 0) {
> dev_err(drm->dev, "Failed to initialise vblank\n");
> - goto err_vblank;
> + return ret;
> }
>
> /* Start with vertical blanking interrupt reporting disabled. */
> @@ -260,7 +246,7 @@ static int mxsfb_load(struct drm_device *drm,
> if (ret) {
> if (ret != -EPROBE_DEFER)
> dev_err(drm->dev, "Cannot connect bridge:
%d\n", ret);
> - goto err_vblank;
> + return ret;
> }
>
> drm->mode_config.min_width = MXSFB_MIN_XRES;
> @@ -277,13 +263,10 @@ static int mxsfb_load(struct drm_device *drm,
> goto err_vblank;
You are still using err_vblank here which gets removed below.
Alexander
> mxsfb->irq = ret;
>
> - pm_runtime_get_sync(drm->dev);
> ret = mxsfb_irq_install(drm, mxsfb->irq);
> - pm_runtime_put_sync(drm->dev);
> -
> if (ret < 0) {
> dev_err(drm->dev, "Failed to install IRQ handler\n");
> - goto err_vblank;
> + return ret;
> }
>
> drm_kms_helper_poll_init(drm);
> @@ -292,12 +275,9 @@ static int mxsfb_load(struct drm_device *drm,
>
> drm_helper_hpd_irq_event(drm);
>
> - return 0;
> -
> -err_vblank:
> - pm_runtime_disable(drm->dev);
> + pm_runtime_enable(drm->dev);
>
> - return ret;
> + return 0;
> }
>
> static void mxsfb_unload(struct drm_device *drm)
> @@ -305,9 +285,7 @@ static void mxsfb_unload(struct drm_device *drm)
> drm_kms_helper_poll_fini(drm);
> drm_mode_config_cleanup(drm);
>
> - pm_runtime_get_sync(drm->dev);
> mxsfb_irq_uninstall(drm);
> - pm_runtime_put_sync(drm->dev);
>
> drm->dev_private = NULL;
>
> @@ -388,23 +366,60 @@ static void mxsfb_shutdown(struct platform_device
> *pdev) drm_atomic_helper_shutdown(drm);
> }
>
> -#ifdef CONFIG_PM_SLEEP
> +static int mxsfb_rpm_suspend(struct device *dev)
> +{
> + struct drm_device *drm = dev_get_drvdata(dev);
> + struct mxsfb_drm_private *mxsfb = drm->dev_private;
> +
> + /* These clock supply the DISPLAY CLOCK Domain */
> + clk_disable_unprepare(mxsfb->clk);
> + /* These clock supply the System Bus, AXI, Write Path, LFIFO */
> + clk_disable_unprepare(mxsfb->clk_disp_axi);
> + /* These clock supply the Control Bus, APB, APBH Ctrl Registers */
> + clk_disable_unprepare(mxsfb->clk_axi);
> +
> + return 0;
> +}
> +
> +static int mxsfb_rpm_resume(struct device *dev)
> +{
> + struct drm_device *drm = dev_get_drvdata(dev);
> + struct mxsfb_drm_private *mxsfb = drm->dev_private;
> +
> + /* These clock supply the Control Bus, APB, APBH Ctrl Registers */
> + clk_prepare_enable(mxsfb->clk_axi);
> + /* These clock supply the System Bus, AXI, Write Path, LFIFO */
> + clk_prepare_enable(mxsfb->clk_disp_axi);
> + /* These clock supply the DISPLAY CLOCK Domain */
> + clk_prepare_enable(mxsfb->clk);
> +
> + return 0;
> +}
> +
> static int mxsfb_suspend(struct device *dev)
> {
> struct drm_device *drm = dev_get_drvdata(dev);
> + int ret;
>
> - return drm_mode_config_helper_suspend(drm);
> + ret = drm_mode_config_helper_suspend(drm);
> + if (ret)
> + return ret;
> +
> + return mxsfb_rpm_suspend(dev);
> }
>
> static int mxsfb_resume(struct device *dev)
> {
> struct drm_device *drm = dev_get_drvdata(dev);
>
> + mxsfb_rpm_resume(dev);
> +
> return drm_mode_config_helper_resume(drm);
> }
> -#endif
>
> static const struct dev_pm_ops mxsfb_pm_ops = {
> + .runtime_suspend = mxsfb_rpm_suspend,
> + .runtime_resume = mxsfb_rpm_resume,
> SET_SYSTEM_SLEEP_PM_OPS(mxsfb_suspend, mxsfb_resume)
> };
>
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> b/drivers/gpu/drm/mxsfb/mxsfb_kms.c index 0655582ae8ed6..03743a84c8e79
> 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> @@ -100,10 +100,6 @@ static void mxsfb_enable_controller(struct
> mxsfb_drm_private *mxsfb) {
> u32 reg;
>
> - if (mxsfb->clk_disp_axi)
> - clk_prepare_enable(mxsfb->clk_disp_axi);
> - clk_prepare_enable(mxsfb->clk);
> -
> /* Increase number of outstanding requests on all supported IPs */
> if (mxsfb->devdata->has_ctrl2) {
> reg = readl(mxsfb->base + LCDC_V4_CTRL2);
> @@ -168,10 +164,6 @@ static void mxsfb_disable_controller(struct
> mxsfb_drm_private *mxsfb) reg = readl(mxsfb->base + LCDC_VDCTRL4);
> reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
> writel(reg, mxsfb->base + LCDC_VDCTRL4);
> -
> - clk_disable_unprepare(mxsfb->clk);
> - if (mxsfb->clk_disp_axi)
> - clk_disable_unprepare(mxsfb->clk_disp_axi);
> }
>
> /*
> @@ -352,9 +344,6 @@ static void mxsfb_crtc_atomic_enable(struct drm_crtc
> *crtc, dma_addr_t paddr;
>
> pm_runtime_get_sync(drm->dev);
> - mxsfb_enable_axi_clk(mxsfb);
> -
> - drm_crtc_vblank_on(crtc);
>
> /* If there is a bridge attached to the LCDIF, use its bus format
*/
> if (mxsfb->bridge) {
> @@ -388,6 +377,8 @@ static void mxsfb_crtc_atomic_enable(struct drm_crtc
> *crtc, }
>
> mxsfb_enable_controller(mxsfb);
> +
> + drm_crtc_vblank_on(crtc);
> }
>
> static void mxsfb_crtc_atomic_disable(struct drm_crtc *crtc,
> @@ -397,6 +388,8 @@ static void mxsfb_crtc_atomic_disable(struct drm_crtc
> *crtc, struct drm_device *drm = mxsfb->drm;
> struct drm_pending_vblank_event *event;
>
> + drm_crtc_vblank_off(crtc);
> +
> mxsfb_disable_controller(mxsfb);
>
> spin_lock_irq(&drm->event_lock);
> @@ -407,9 +400,6 @@ static void mxsfb_crtc_atomic_disable(struct drm_crtc
> *crtc, }
> spin_unlock_irq(&drm->event_lock);
>
> - drm_crtc_vblank_off(crtc);
> -
> - mxsfb_disable_axi_clk(mxsfb);
> pm_runtime_put_sync(drm->dev);
> }
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