Commit 73743e72 authored by Kalyan Thota's avatar Kalyan Thota Committed by Rob Clark
Browse files

drm/msm/disp/dpu1: turn off vblank irqs aggressively in dpu driver 



Set the flag vblank_disable_immediate = true to turn off vblank irqs
immediately as soon as drm_vblank_put is requested so that there are
no irqs triggered during idle state. This will reduce cpu wakeups
and help in power saving.

To enable vblank_disable_immediate flag the underlying KMS driver
needs to support high precision vblank timestamping and also a
reliable way of providing vblank counter which is incrementing
at the leading edge of vblank.

This patch also brings in changes to support vblank_disable_immediate
requirement in dpu driver.

Changes in v1:
 - Specify reason to add vblank timestamp support. (Rob).
 - Add changes to provide vblank counter from dpu driver.

Changes in v2:
 - Fix warn stack reported by Rob Clark with v2 patch.

Changes in v3:
 - Move back to HW frame counter (Rob).

Changes in v4:
 - Frame count mismatch was causing a DRM WARN stack spew.
   DPU HW will increment the frame count at the end of
   the sync, where as vblank will be triggered at the
   fetch_start counter which is calculated as v_total - vfp.
   This is to start fetching early for panels with low
   vbp w.r.t hw latency lines.

   Add logic to detect the line count if it falls between
   vactive and v_total then return incremented frame count value.

Signed-off-by: default avatarKalyan Thota <kalyan_t@codeaurora.org>
Link: https://lore.kernel.org/r/1613651746-12783-1-git-send-email-kalyan_t@codeaurora.org


Signed-off-by: default avatarRob Clark <robdclark@chromium.org>
parent 3ab1c5cc

drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c

+80 −0
Original line number Diff line number Diff line
@@ -66,6 +66,83 @@ static void dpu_crtc_destroy(struct drm_crtc *crtc) 
	kfree(dpu_crtc);

}



static struct drm_encoder *get_encoder_from_crtc(struct drm_crtc *crtc)

{

	struct drm_device *dev = crtc->dev;

	struct drm_encoder *encoder;



	drm_for_each_encoder(encoder, dev)

		if (encoder->crtc == crtc)

			return encoder;



	return NULL;

}



static u32 dpu_crtc_get_vblank_counter(struct drm_crtc *crtc)

{

	struct drm_encoder *encoder;



	encoder = get_encoder_from_crtc(crtc);

	if (!encoder) {

		DRM_ERROR("no encoder found for crtc %d\n", crtc->index);

		return false;

	}



	return dpu_encoder_get_frame_count(encoder);

}



static bool dpu_crtc_get_scanout_position(struct drm_crtc *crtc,

					   bool in_vblank_irq,

					   int *vpos, int *hpos,

					   ktime_t *stime, ktime_t *etime,

					   const struct drm_display_mode *mode)

{

	unsigned int pipe = crtc->index;

	struct drm_encoder *encoder;

	int line, vsw, vbp, vactive_start, vactive_end, vfp_end;



	encoder = get_encoder_from_crtc(crtc);

	if (!encoder) {

		DRM_ERROR("no encoder found for crtc %d\n", pipe);

		return false;

	}



	vsw = mode->crtc_vsync_end - mode->crtc_vsync_start;

	vbp = mode->crtc_vtotal - mode->crtc_vsync_end;



	/*

	 * the line counter is 1 at the start of the VSYNC pulse and VTOTAL at

	 * the end of VFP. Translate the porch values relative to the line

	 * counter positions.

	 */



	vactive_start = vsw + vbp + 1;

	vactive_end = vactive_start + mode->crtc_vdisplay;



	/* last scan line before VSYNC */

	vfp_end = mode->crtc_vtotal;



	if (stime)

		*stime = ktime_get();



	line = dpu_encoder_get_linecount(encoder);



	if (line < vactive_start)

		line -= vactive_start;

	else if (line > vactive_end)

		line = line - vfp_end - vactive_start;

	else

		line -= vactive_start;



	*vpos = line;

	*hpos = 0;



	if (etime)

		*etime = ktime_get();



	return true;

}



static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,

		struct dpu_plane_state *pstate, struct dpu_format *format)

{
@@ -1249,6 +1326,8 @@ static const struct drm_crtc_funcs dpu_crtc_funcs = { 
	.early_unregister = dpu_crtc_early_unregister,

	.enable_vblank  = msm_crtc_enable_vblank,

	.disable_vblank = msm_crtc_disable_vblank,

	.get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,

	.get_vblank_counter = dpu_crtc_get_vblank_counter,

};



static const struct drm_crtc_helper_funcs dpu_crtc_helper_funcs = {
@@ -1257,6 +1336,7 @@ static const struct drm_crtc_helper_funcs dpu_crtc_helper_funcs = { 
	.atomic_check = dpu_crtc_atomic_check,

	.atomic_begin = dpu_crtc_atomic_begin,

	.atomic_flush = dpu_crtc_atomic_flush,

	.get_scanout_position = dpu_crtc_get_scanout_position,

};



/* initialize crtc */

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c

+30 −0
Original line number Diff line number Diff line
@@ -426,6 +426,36 @@ int dpu_encoder_helper_unregister_irq(struct dpu_encoder_phys *phys_enc, 
	return 0;

}



int dpu_encoder_get_frame_count(struct drm_encoder *drm_enc)

{

	struct dpu_encoder_virt *dpu_enc;

	struct dpu_encoder_phys *phys;

	int framecount = 0;



	dpu_enc = to_dpu_encoder_virt(drm_enc);

	phys = dpu_enc ? dpu_enc->cur_master : NULL;



	if (phys && phys->ops.get_frame_count)

		framecount = phys->ops.get_frame_count(phys);



	return framecount;

}



int dpu_encoder_get_linecount(struct drm_encoder *drm_enc)

{

	struct dpu_encoder_virt *dpu_enc;

	struct dpu_encoder_phys *phys;

	int linecount = 0;



	dpu_enc = to_dpu_encoder_virt(drm_enc);

	phys = dpu_enc ? dpu_enc->cur_master : NULL;



	if (phys && phys->ops.get_line_count)

		linecount = phys->ops.get_line_count(phys);



	return linecount;

}



void dpu_encoder_get_hw_resources(struct drm_encoder *drm_enc,

				  struct dpu_encoder_hw_resources *hw_res)

{

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h

+11 −0
Original line number Diff line number Diff line
@@ -156,5 +156,16 @@ void dpu_encoder_prepare_commit(struct drm_encoder *drm_enc); 
 */

void dpu_encoder_set_idle_timeout(struct drm_encoder *drm_enc,

							u32 idle_timeout);

/**

 * dpu_encoder_get_linecount - get interface line count for the encoder.

 * @drm_enc:    Pointer to previously created drm encoder structure

 */

int dpu_encoder_get_linecount(struct drm_encoder *drm_enc);



/**

 * dpu_encoder_get_frame_count - get interface frame count for the encoder.

 * @drm_enc:    Pointer to previously created drm encoder structure

 */

int dpu_encoder_get_frame_count(struct drm_encoder *drm_enc);



#endif /* __DPU_ENCODER_H__ */

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h

+1 −0
Original line number Diff line number Diff line
@@ -143,6 +143,7 @@ struct dpu_encoder_phys_ops { 
	void (*prepare_idle_pc)(struct dpu_encoder_phys *phys_enc);

	void (*restore)(struct dpu_encoder_phys *phys);

	int (*get_line_count)(struct dpu_encoder_phys *phys);

	int (*get_frame_count)(struct dpu_encoder_phys *phys);

};



/**

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c

+26 −0
Original line number Diff line number Diff line
@@ -658,6 +658,31 @@ static int dpu_encoder_phys_vid_get_line_count( 
	return phys_enc->hw_intf->ops.get_line_count(phys_enc->hw_intf);

}



static int dpu_encoder_phys_vid_get_frame_count(

		struct dpu_encoder_phys *phys_enc)

{

	struct intf_status s = {0};

	u32 fetch_start = 0;

	struct drm_display_mode mode = phys_enc->cached_mode;



	if (!dpu_encoder_phys_vid_is_master(phys_enc))

		return -EINVAL;



	if (!phys_enc->hw_intf || !phys_enc->hw_intf->ops.get_status)

		return -EINVAL;



	phys_enc->hw_intf->ops.get_status(phys_enc->hw_intf, &s);



	if (s.is_prog_fetch_en && s.is_en) {

		fetch_start = mode.vtotal - (mode.vsync_start - mode.vdisplay);

		if ((s.line_count > fetch_start) &&

			(s.line_count <= mode.vtotal))

			return s.frame_count + 1;

	}



	return s.frame_count;

}



static void dpu_encoder_phys_vid_init_ops(struct dpu_encoder_phys_ops *ops)

{

	ops->is_master = dpu_encoder_phys_vid_is_master;
@@ -676,6 +701,7 @@ static void dpu_encoder_phys_vid_init_ops(struct dpu_encoder_phys_ops *ops) 
	ops->handle_post_kickoff = dpu_encoder_phys_vid_handle_post_kickoff;

	ops->needs_single_flush = dpu_encoder_phys_vid_needs_single_flush;

	ops->get_line_count = dpu_encoder_phys_vid_get_line_count;

	ops->get_frame_count = dpu_encoder_phys_vid_get_frame_count;

}



struct dpu_encoder_phys *dpu_encoder_phys_vid_init(