On Wed, Nov 14, 2018 at 02:43:51PM -0500, Sean Paul wrote: > On Wed, Nov 14, 2018 at 11:33:53AM -0800, Jeykumar Sankaran wrote: > > On 2018-11-14 07:13, Sean Paul wrote: > > > On Tue, Nov 13, 2018 at 04:47:22PM -0800, Jeykumar Sankaran wrote: > > > > On 2018-11-13 12:52, Sean Paul wrote: > > > > > From: Sean Paul <seanp...@chromium.org> > > > > > > > > > > The indirection of registering a callback and opaque pointer isn't > > > real > > > > > useful when there's only one callsite. So instead of having the > > > > > vblank_cb registration, just give encoder a crtc and let it directly > > > > > call the vblank handler. > > > > > > > > > > In a later patch, we'll make use of this further. > > > > > > > > > > Signed-off-by: Sean Paul <seanp...@chromium.org> > > > > > --- > > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 8 +++---- > > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h | 6 +++++ > > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 25 > > > +++++++++++---------- > > > > > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 10 ++++----- > > > > > 4 files changed, 26 insertions(+), 23 deletions(-) > > > > > > > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > > > > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > > > > > index adda0aa0cbaa..38119b4d4a80 100644 > > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c > > > > > @@ -291,9 +291,8 @@ enum dpu_intf_mode dpu_crtc_get_intf_mode(struct > > > > > drm_crtc *crtc) > > > > > return INTF_MODE_NONE; > > > > > } > > > > > > > > > > -static void dpu_crtc_vblank_cb(void *data) > > > > > +void dpu_crtc_vblank_callback(struct drm_crtc *crtc) > > > > > { > > > > > - struct drm_crtc *crtc = (struct drm_crtc *)data; > > > > > struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc); > > > > > > > > Since we are calling into a locally stored CRTC and not tracking > > > disable. > > > > Should > > > > we check for crtc->enable before processing the callback? > > > > > > > > I see vblank_on/off cant be called when CRTC is disabled with the rest > > > > of the patches in the series. But this callback is triggered by IRQ's > > > > context. > > > > > > Hmm, yeah, I had assumed that we wouldn't have any interrupts after irq > > > disable. > > > However it doesn't seem like that's the case. > > > > > > That said, I don't think checking crtc->enable is quite what we want. In > > > the > > > case of disable, the crtc is cleared from the encoder, so checking for > > > crtc != NULL would be better here. SGTY? > > That would still cause a race as crtc assignment will be protected by > > modeset > > locks and crtc != NULL check isn't. > > Right, we'd need to wrap the callback in the encoder spinlock.
Just went to do this, and it's already wrapped in the encoder spinlock. So AFAICT, no further changes needed. Sean > > > > > > > Now that I've dug into the vblank irq handling a bit in the encoder, it > > > seems > > > like that could be moved to the crtc and a bunch of the > > > encoder->crtc->encoder > > > bouncing around could be avoided. Off the top of your head, is there any > > > reason > > > we couldn't move the vblank irq handling into crtc from encoder? > > vblank irq handlers are only needed for video mode. As with all the other > > IRQ's, the handlers are implemented in phys_encoder level and the events > > are forwarded as and when needed. > > > > I took a look at how that might work, and it seems possible but probably not > worthwhile. > > Sean > > > BTW, the vblank irq flows from phys_enc->virtual_enc->crtc. > > > > Thanks, > > Jeykumar S. > > > > > > > > Sean > > > > > > > > > > > > > > > > > /* keep statistics on vblank callback - with auto reset via > > > > > debugfs */ > > > > > @@ -779,8 +778,7 @@ static void _dpu_crtc_vblank_enable_no_lock( > > > > > DRMID(enc), enable, > > > > > dpu_crtc); > > > > > > > > > > - dpu_encoder_register_vblank_callback(enc, > > > > > - dpu_crtc_vblank_cb, (void > > > > > *)crtc); > > > > > + dpu_encoder_assign_crtc(enc, crtc); > > > > > } > > > > > } else { > > > > > list_for_each_entry(enc, &dev->mode_config.encoder_list, > > > > > head) { > > > > > @@ -791,7 +789,7 @@ static void _dpu_crtc_vblank_enable_no_lock( > > > > > DRMID(enc), enable, > > > > > dpu_crtc); > > > > > > > > > > - dpu_encoder_register_vblank_callback(enc, NULL, > > > > > NULL); > > > > > + dpu_encoder_assign_crtc(enc, NULL); > > > > > } > > > > > } > > > > > } > > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h > > > > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h > > > > > index 93d21a61a040..54595cc29be5 100644 > > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h > > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h > > > > > @@ -270,6 +270,12 @@ static inline int dpu_crtc_frame_pending(struct > > > > > drm_crtc *crtc) > > > > > */ > > > > > int dpu_crtc_vblank(struct drm_crtc *crtc, bool en); > > > > > > > > > > +/** > > > > > + * dpu_crtc_vblank_callback - called on vblank irq, issues completion > > > > > events > > > > > + * @crtc: Pointer to drm crtc object > > > > > + */ > > > > > +void dpu_crtc_vblank_callback(struct drm_crtc *crtc); > > > > > + > > > > > /** > > > > > * dpu_crtc_commit_kickoff - trigger kickoff of the commit for this > > > > > crtc > > > > > * @crtc: Pointer to drm crtc object > > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > > > > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > > > > > index d89ac520f7e6..fd6514f681ae 100644 > > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c > > > > > @@ -142,9 +142,11 @@ enum dpu_enc_rc_states { > > > > > * @intfs_swapped Whether or not the phys_enc interfaces have been > > > > > swapped > > > > > * for partial update right-only cases, such as > > > > > pingpong > > > > > * split where virtual pingpong does not generate > > > > > IRQs > > > > > - * @crtc_vblank_cb: Callback into the upper layer / CRTC for > > > > > - * notification of the VBLANK > > > > > - * @crtc_vblank_cb_data: Data from upper layer for VBLANK > > > > > notification > > > > > + * @crtc: Pointer to the currently assigned crtc. Normally > > > > > you > > > > > + * would use crtc->state->encoder_mask to determine > > > > > the > > > > > + * link between encoder/crtc. However in this case > > > > > we > > > > > need > > > > > + * to track crtc in the disable() hook which is > > > > > called > > > > > + * _after_ encoder_mask is cleared. > > > > > * @crtc_kickoff_cb: Callback into CRTC that will flush > > > & start > > > > > * all CTL paths > > > > > * @crtc_kickoff_cb_data: Opaque user data given to > > > > > crtc_kickoff_cb > > > > > @@ -186,8 +188,7 @@ struct dpu_encoder_virt { > > > > > > > > > > bool intfs_swapped; > > > > > > > > > > - void (*crtc_vblank_cb)(void *); > > > > > - void *crtc_vblank_cb_data; > > > > > + struct drm_crtc *crtc; > > > > > > > > > > struct dentry *debugfs_root; > > > > > struct mutex enc_lock; > > > > > @@ -1241,8 +1242,8 @@ static void dpu_encoder_vblank_callback(struct > > > > > drm_encoder *drm_enc, > > > > > dpu_enc = to_dpu_encoder_virt(drm_enc); > > > > > > > > > > spin_lock_irqsave(&dpu_enc->enc_spinlock, lock_flags); > > > > > - if (dpu_enc->crtc_vblank_cb) > > > > > - dpu_enc->crtc_vblank_cb(dpu_enc->crtc_vblank_cb_data); > > > > > + 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); > > > > > @@ -1262,15 +1263,14 @@ static void > > > dpu_encoder_underrun_callback(struct > > > > > drm_encoder *drm_enc, > > > > > DPU_ATRACE_END("encoder_underrun_callback"); > > > > > } > > > > > > > > > > -void dpu_encoder_register_vblank_callback(struct drm_encoder > > > *drm_enc, > > > > > - void (*vbl_cb)(void *), void *vbl_data) > > > > > +void dpu_encoder_assign_crtc(struct drm_encoder *drm_enc, struct > > > > > drm_crtc > > > > > *crtc) > > > > > { > > > > > struct dpu_encoder_virt *dpu_enc = to_dpu_encoder_virt(drm_enc); > > > > > unsigned long lock_flags; > > > > > bool enable; > > > > > int i; > > > > > > > > > > - enable = vbl_cb ? true : false; > > > > > + enable = crtc ? true : false; > > > > > > > > > > if (!drm_enc) { > > > > > DPU_ERROR("invalid encoder\n"); > > > > > @@ -1279,8 +1279,9 @@ void dpu_encoder_register_vblank_callback(struct > > > > > drm_encoder *drm_enc, > > > > > trace_dpu_enc_vblank_cb(DRMID(drm_enc), enable); > > > > > > > > > > spin_lock_irqsave(&dpu_enc->enc_spinlock, lock_flags); > > > > > - dpu_enc->crtc_vblank_cb = vbl_cb; > > > > > - dpu_enc->crtc_vblank_cb_data = vbl_data; > > > > > + /* crtc should always be cleared before re-assigning */ > > > > > + WARN_ON(crtc && dpu_enc->crtc); > > > > > + dpu_enc->crtc = crtc; > > > > > spin_unlock_irqrestore(&dpu_enc->enc_spinlock, lock_flags); > > > > > > > > > > for (i = 0; i < dpu_enc->num_phys_encs; i++) { > > > > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > > > > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > > > > > index aa4f135218fa..be1d80867834 100644 > > > > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > > > > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h > > > > > @@ -55,14 +55,12 @@ void dpu_encoder_get_hw_resources(struct > > > drm_encoder > > > > > *encoder, > > > > > struct dpu_encoder_hw_resources > > > > > *hw_res); > > > > > > > > > > /** > > > > > - * dpu_encoder_register_vblank_callback - provide callback to encoder > > > > > that > > > > > - * will be called on the next vblank. > > > > > + * dpu_encoder_assign_crtc - Link the encoder to the crtc it's > > > assigned > > > > > to > > > > > * @encoder: encoder pointer > > > > > - * @cb: callback pointer, provide NULL to deregister and > > > > > disable IRQs > > > > > - * @data: user data provided to callback > > > > > + * @crtc: crtc pointer > > > > > */ > > > > > -void dpu_encoder_register_vblank_callback(struct drm_encoder > > > *encoder, > > > > > - void (*cb)(void *), void *data); > > > > > +void dpu_encoder_assign_crtc(struct drm_encoder *encoder, > > > > > + struct drm_crtc *crtc); > > > > > > > > > > /** > > > > > * dpu_encoder_register_frame_event_callback - provide callback to > > > > > encoder that > > > > > > > > -- > > > > Jeykumar S > > > > -- > > Jeykumar S > > -- > Sean Paul, Software Engineer, Google / Chromium OS -- Sean Paul, Software Engineer, Google / Chromium OS _______________________________________________ Freedreno mailing list Freedreno@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/freedreno