On Fri, Feb 12, 2021 at 3:45 AM Kalyan Thota <kalyant@xxxxxxxxxxxxxx> wrote: > > 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 with v2 patch > > Signed-off-by: Kalyan Thota <kalyant@xxxxxxxxxxxxxx> > --- > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 80 +++++++++++++++++++++++++++++ > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 28 +++++++++- > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 11 ++++ > drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 5 ++ > 4 files changed, 123 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > index d4662e8..9a80981 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > @@ -65,6 +65,83 @@ 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) > { > @@ -1243,6 +1320,8 @@ 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 = { > @@ -1251,6 +1330,7 @@ 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 */ > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > index f7f5c25..fb6546c 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > @@ -425,6 +425,32 @@ 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 *phy_enc; > + > + dpu_enc = to_dpu_encoder_virt(drm_enc); > + phy_enc = dpu_enc ? dpu_enc->cur_master : NULL; > + > + return phy_enc ? atomic_read(&phy_enc->vsync_cnt) : 0; I don't think we should use a sw vsync_cntr.. or at least not use it for anything more than detecting that we are in this post-vblank limbo period But might as well keep the discussion on the v2 thread BR, -R > +} > + > +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) > { > @@ -1296,12 +1322,12 @@ static void dpu_encoder_vblank_callback(struct drm_encoder *drm_enc, > DPU_ATRACE_BEGIN("encoder_vblank_callback"); > dpu_enc = to_dpu_encoder_virt(drm_enc); > > + atomic_inc(&phy_enc->vsync_cnt); > spin_lock_irqsave(&dpu_enc->enc_spinlock, lock_flags); > if (dpu_enc->crtc) > dpu_crtc_vblank_callback(dpu_enc->crtc); > spin_unlock_irqrestore(&dpu_enc->enc_spinlock, lock_flags); > > - atomic_inc(&phy_enc->vsync_cnt); > DPU_ATRACE_END("encoder_vblank_callback"); > } > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > index b491346..99a5d73 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > @@ -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__ */ > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c > index 374b0e8..ed636f1 100644 > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c > @@ -14,6 +14,7 @@ > > #include <drm/drm_crtc.h> > #include <drm/drm_file.h> > +#include <drm/drm_vblank.h> > > #include "msm_drv.h" > #include "msm_mmu.h" > @@ -1020,6 +1021,10 @@ static int dpu_kms_hw_init(struct msm_kms *kms) > */ > dev->mode_config.allow_fb_modifiers = true; > > + dev->max_vblank_count = 0xffffffff; > + /* Disable vblank irqs aggressively for power-saving */ > + dev->vblank_disable_immediate = true; > + > /* > * _dpu_kms_drm_obj_init should create the DRM related objects > * i.e. CRTCs, planes, encoders, connectors and so forth > -- > 2.7.4 > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel