Re: [PATCH v4 3/8] drm/mediatek: add shadow register support

Hi, YT:

One comment inline.

On Fri, 2016-07-15 at 18:07 +0800, YT Shen wrote:

We need to acquire mutex before using the resources, and need to release it after finished. So we don't need to write registers in the blanking period.

Signed-off-by: YT Shen yt.shen@mediatek.com

drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 75 +++++++++++++++++++------------ drivers/gpu/drm/mediatek/mtk_drm_ddp.c | 22 +++++++++ drivers/gpu/drm/mediatek/mtk_drm_ddp.h | 2 + drivers/gpu/drm/mediatek/mtk_drm_drv.h | 1 + 4 files changed, 71 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c index 24aa3ba..80d9641 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c @@ -315,6 +315,42 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_drm_crtc *mtk_crtc) pm_runtime_put(drm->dev); }

+static void mtk_crtc_ddp_config(struct drm_crtc *crtc) +{

• struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
• struct mtk_crtc_state *state = to_mtk_crtc_state(mtk_crtc->base.state);
• struct mtk_ddp_comp *ovl = mtk_crtc->ddp_comp[0];
• unsigned int i;
• /*

• * TODO: instead of updating the registers here, we should prepare
  

• * working registers in atomic_commit and let the hardware command
  

• * queue update module registers on vblank.
  

• */
  

• if (state->pending_config) {

• mtk_ddp_comp_config(ovl, state->pending_width,
  

• 		    state->pending_height,
  

• 		    state->pending_vrefresh);
  

• state->pending_config = false;
  

• }
• if (mtk_crtc->pending_planes) {

• for (i = 0; i < OVL_LAYER_NR; i++) {
  

• 	struct drm_plane *plane = &mtk_crtc->planes[i].base;
  

• 	struct mtk_plane_state *plane_state;
  

• 	plane_state = to_mtk_plane_state(plane->state);
  

• 	if (plane_state->pending.config) {
  

• 		mtk_ddp_comp_layer_config(ovl, i, plane_state);
  

• 		plane_state->pending.config = false;
  

• 	}
  

• }
  

• mtk_crtc->pending_planes = false;
  

• }

+}

static void mtk_drm_crtc_enable(struct drm_crtc *crtc) { struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc); @@ -391,6 +427,7 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc, struct drm_crtc_state *old_crtc_state) { struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);

• struct mtk_drm_private *priv = crtc->dev->dev_private; unsigned int pending_planes = 0; int i;

@@ -409,6 +446,12 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc, } if (pending_planes) mtk_crtc->pending_planes = true;

• if (priv->data->shadow_register) {

• mtk_disp_mutex_acquire(mtk_crtc->mutex);
  

• mtk_crtc_ddp_config(crtc);
  

• mtk_disp_mutex_release(mtk_crtc->mutex);
  

• }

}

static const struct drm_crtc_funcs mtk_crtc_funcs = { @@ -453,36 +496,10 @@ err_cleanup_crtc: void mtk_crtc_ddp_irq(struct drm_crtc *crtc, struct mtk_ddp_comp *ovl) { struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);

• struct mtk_crtc_state *state = to_mtk_crtc_state(mtk_crtc->base.state);
• unsigned int i;

• struct mtk_drm_private *priv = crtc->dev->dev_private;

• /*

• * TODO: instead of updating the registers here, we should prepare
  

• * working registers in atomic_commit and let the hardware command
  

• * queue update module registers on vblank.
  

• */
  

• if (state->pending_config) {

• mtk_ddp_comp_config(ovl, state->pending_width,
  

• 		    state->pending_height,
  

• 		    state->pending_vrefresh);
  

• state->pending_config = false;
  

• }
• if (mtk_crtc->pending_planes) {

• for (i = 0; i < OVL_LAYER_NR; i++) {
  

• 	struct drm_plane *plane = &mtk_crtc->planes[i].base;
  

• 	struct mtk_plane_state *plane_state;
  

• 	plane_state = to_mtk_plane_state(plane->state);
  

• 	if (plane_state->pending.config) {
  

• 		mtk_ddp_comp_layer_config(ovl, i, plane_state);
  

• 		plane_state->pending.config = false;
  

• 	}
  

• }
  

• mtk_crtc->pending_planes = false;
  

• }

• if (!priv->data->shadow_register)

• mtk_crtc_ddp_config(crtc);
  
  

  mtk_drm_finish_page_flip(mtk_crtc);

} diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c index 8030769..fa53806 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c @@ -12,6 +12,7 @@ */

#include <linux/clk.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> @@ -32,6 +33,7 @@ #define DISP_REG_CONFIG_MMSYS_CG_CON0 0x100

#define DISP_REG_MUTEX_EN(n) (0x20 + 0x20 * (n)) +#define DISP_REG_MUTEX(n) (0x24 + 0x20 * (n)) #define DISP_REG_MUTEX_RST(n) (0x28 + 0x20 * (n)) #define DISP_REG_MUTEX_MOD(n) (0x2c + 0x20 * (n)) #define DISP_REG_MUTEX_SOF(n) (0x30 + 0x20 * (n)) @@ -300,6 +302,26 @@ void mtk_disp_mutex_disable(struct mtk_disp_mutex *mutex) writel(0, ddp->regs + DISP_REG_MUTEX_EN(mutex->id)); }

+void mtk_disp_mutex_acquire(struct mtk_disp_mutex *mutex) +{

• struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,

• 			   mutex[mutex->id]);
  

• u32 tmp;
• writel(1, ddp->regs + DISP_REG_MUTEX_EN(mutex->id));
• writel(1, ddp->regs + DISP_REG_MUTEX(mutex->id));
• readl_poll_timeout_atomic(ddp->regs + DISP_REG_MUTEX(mutex->id), tmp,

• 		  tmp & 0x2, 1, 10000);
  

Nothing to do with timeout? I think it should print error message here or reset HW to recover it.

+}

+void mtk_disp_mutex_release(struct mtk_disp_mutex *mutex) +{

• struct mtk_ddp *ddp = container_of(mutex, struct mtk_ddp,

• 			   mutex[mutex->id]);
  

• writel(0, ddp->regs + DISP_REG_MUTEX(mutex->id));

+}

static int mtk_ddp_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp.h index 92c1175..f9a7991 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.h @@ -37,5 +37,7 @@ void mtk_disp_mutex_remove_comp(struct mtk_disp_mutex *mutex, enum mtk_ddp_comp_id id); void mtk_disp_mutex_unprepare(struct mtk_disp_mutex *mutex); void mtk_disp_mutex_put(struct mtk_disp_mutex *mutex); +void mtk_disp_mutex_acquire(struct mtk_disp_mutex *mutex); +void mtk_disp_mutex_release(struct mtk_disp_mutex *mutex);

#endif /* MTK_DRM_DDP_H */ diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h index fa0b106..94f8b66 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h @@ -33,6 +33,7 @@ struct mtk_mmsys_driver_data { unsigned int main_len; const enum mtk_ddp_comp_id *ext_path; unsigned int ext_len;

• bool shadow_register;

};

struct mtk_drm_private {