On Thu, 20 Nov 2025, Ville Syrjala <[email protected]> wrote: > From: Ville Syrjälä <[email protected]> > > Currently our crtcs are registered in pipe order, and thus > all the for_intel_crtc*() iterators walk the crtcs in pipe > order. There are a bunch of places that more or less depend > on that. Eg. during plane updates and such we want joined > pipes to be processed back-to-back to give a better chance > of an atomic update across the whole set. > > When we start to register crtcs in a different order we don't > want to change the order in which the pipes get handled. > Decouple the for_each_intel_crtc*() iterators from the crtc > registration order by using a separate list which will be > sorted by the pipe rather than the crtc index. > > We could priobably use a simple array or something, but that > would require some kind of extra iterator variable for the > macros, and thus would require a lot more changes. Using > a linked list keeps the fallout minimal. We can look at > using a more optimal data structure later.
I think the list works fine. > I also added this extra junk to the atomic state iterators: > "(__i) = drm_crtc_index(&(crtc)->base), (void)(__i)" > even though the macro itself no longer needs the "__i" iterator. > This in case the "__i" is used by the caller, and to > avoid compiler warnings if it's completely unused now. At a glance, I can't find any. Perhaps you could cook up some cocci to remove the parameter as follow-up? > Signed-off-by: Ville Syrjälä <[email protected]> > --- > drivers/gpu/drm/i915/display/intel_crtc.c | 20 +++++ > drivers/gpu/drm/i915/display/intel_display.h | 90 ++++++++----------- > .../gpu/drm/i915/display/intel_display_core.h | 3 + > .../drm/i915/display/intel_display_driver.c | 1 + > .../drm/i915/display/intel_display_types.h | 1 + > drivers/gpu/drm/xe/display/xe_display.c | 1 + > 6 files changed, 64 insertions(+), 52 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c > b/drivers/gpu/drm/i915/display/intel_crtc.c > index 153ff4b4b52c..7ebbde716238 100644 > --- a/drivers/gpu/drm/i915/display/intel_crtc.c > +++ b/drivers/gpu/drm/i915/display/intel_crtc.c > @@ -209,6 +209,8 @@ static struct intel_crtc *intel_crtc_alloc(void) > crtc->base.state = &crtc_state->uapi; > crtc->config = crtc_state; > > + INIT_LIST_HEAD(&crtc->pipe_head); > + > return crtc; > } > > @@ -222,6 +224,8 @@ static void intel_crtc_destroy(struct drm_crtc *_crtc) > { > struct intel_crtc *crtc = to_intel_crtc(_crtc); > > + list_del(&crtc->pipe_head); > + > cpu_latency_qos_remove_request(&crtc->vblank_pm_qos); > > drm_crtc_cleanup(&crtc->base); > @@ -308,6 +312,20 @@ static const struct drm_crtc_funcs i8xx_crtc_funcs = { > .get_vblank_timestamp = intel_crtc_get_vblank_timestamp, > }; > > +static void add_crtc_to_pipe_list(struct intel_display *display, struct > intel_crtc *crtc) > +{ > + struct intel_crtc *iter; > + > + list_for_each_entry(iter, &display->pipe_list, pipe_head) { > + if (iter->pipe > crtc->pipe) { Nitpick, somehow I found it easier to think of this in reverse order, "crtc->pipe < iter->pipe", but could be just me. *shrug*. > + list_add_tail(&crtc->pipe_head, &iter->pipe_head); > + return; > + } > + } > + > + list_add_tail(&crtc->pipe_head, &display->pipe_list); > +} > + > int intel_crtc_init(struct intel_display *display, enum pipe pipe) > { > struct intel_plane *primary, *cursor; > @@ -398,6 +416,8 @@ int intel_crtc_init(struct intel_display *display, enum > pipe pipe) > if (HAS_CASF(display)) > drm_crtc_create_sharpness_strength_property(&crtc->base); > > + add_crtc_to_pipe_list(display, crtc); > + > return 0; > > fail: > diff --git a/drivers/gpu/drm/i915/display/intel_display.h > b/drivers/gpu/drm/i915/display/intel_display.h > index bcc6ccb69d2b..ac83d4f09bb9 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.h > +++ b/drivers/gpu/drm/i915/display/intel_display.h > @@ -238,22 +238,23 @@ enum phy_fia { > base.head) \ > for_each_if((intel_plane)->pipe == (intel_crtc)->pipe) > > -#define for_each_intel_crtc(dev, intel_crtc) \ > - list_for_each_entry(intel_crtc, \ > - &(dev)->mode_config.crtc_list, \ > - base.head) > +#define for_each_intel_crtc(dev, crtc) \ > + list_for_each_entry((crtc), \ > + &to_intel_display(dev)->pipe_list, \ > + pipe_head) > > -#define for_each_intel_crtc_in_pipe_mask(dev, intel_crtc, pipe_mask) \ > - list_for_each_entry(intel_crtc, \ > - &(dev)->mode_config.crtc_list, \ > - base.head) \ > - for_each_if((pipe_mask) & BIT(intel_crtc->pipe)) > +#define for_each_intel_crtc_reverse(dev, crtc) \ > + list_for_each_entry_reverse((crtc), \ > + &to_intel_display(dev)->pipe_list, \ > + pipe_head) > > -#define for_each_intel_crtc_in_pipe_mask_reverse(dev, intel_crtc, pipe_mask) > \ > - list_for_each_entry_reverse((intel_crtc), > \ > - &(dev)->mode_config.crtc_list, > \ > - base.head) > \ > - for_each_if((pipe_mask) & BIT((intel_crtc)->pipe)) > +#define for_each_intel_crtc_in_pipe_mask(dev, crtc, pipe_mask) \ > + for_each_intel_crtc((dev), (crtc)) \ > + for_each_if((pipe_mask) & BIT((crtc)->pipe)) > + > +#define for_each_intel_crtc_in_pipe_mask_reverse(dev, crtc, pipe_mask) \ > + for_each_intel_crtc_reverse((dev), (crtc)) \ > + for_each_if((pipe_mask) & BIT((crtc)->pipe)) > > #define for_each_intel_encoder(dev, intel_encoder) \ > list_for_each_entry(intel_encoder, \ > @@ -295,14 +296,6 @@ enum phy_fia { > (__i)++) \ > for_each_if(plane) > > -#define for_each_old_intel_crtc_in_state(__state, crtc, old_crtc_state, __i) > \ > - for ((__i) = 0; \ > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > - (old_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), 1); \ > - (__i)++) \ > - for_each_if(crtc) > - > #define for_each_new_intel_plane_in_state(__state, plane, new_plane_state, > __i) \ > for ((__i) = 0; \ > (__i) < (__state)->base.dev->mode_config.num_total_plane && \ > @@ -311,22 +304,6 @@ enum phy_fia { > (__i)++) \ > for_each_if(plane) > > -#define for_each_new_intel_crtc_in_state(__state, crtc, new_crtc_state, __i) > \ > - for ((__i) = 0; \ > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > - (new_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > - (__i)++) \ > - for_each_if(crtc) > - > -#define for_each_new_intel_crtc_in_state_reverse(__state, crtc, > new_crtc_state, __i) \ > - for ((__i) = (__state)->base.dev->mode_config.num_crtc - 1; \ > - (__i) >= 0 && \ > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > - (new_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > - (__i)--) \ > - for_each_if(crtc) > - > #define for_each_oldnew_intel_plane_in_state(__state, plane, > old_plane_state, new_plane_state, __i) \ > for ((__i) = 0; \ > (__i) < (__state)->base.dev->mode_config.num_total_plane && \ > @@ -336,23 +313,32 @@ enum phy_fia { > (__i)++) \ > for_each_if(plane) > > +#define for_each_old_intel_crtc_in_state(__state, crtc, old_crtc_state, __i) > \ > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > (void)(__i), \ > + (old_crtc_state) = > intel_atomic_get_old_crtc_state((__state), (crtc)))) > + > +#define for_each_new_intel_crtc_in_state(__state, crtc, new_crtc_state, __i) > \ > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > (void)(__i), \ > + (new_crtc_state) = > intel_atomic_get_new_crtc_state((__state), (crtc)))) > + > +#define for_each_new_intel_crtc_in_state_reverse(__state, crtc, > new_crtc_state, __i) \ > + for_each_intel_crtc_reverse((__state)->base.dev, (crtc)) \ > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > (void)(__i), \ > + (new_crtc_state) = > intel_atomic_get_new_crtc_state((__state), (crtc)))) > + > #define for_each_oldnew_intel_crtc_in_state(__state, crtc, old_crtc_state, > new_crtc_state, __i) \ > - for ((__i) = 0; \ > - (__i) < (__state)->base.dev->mode_config.num_crtc && \ > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > - (old_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), \ > - (new_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > - (__i)++) \ > - for_each_if(crtc) > + for_each_intel_crtc((__state)->base.dev, (crtc)) \ > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > (void)(__i), \ > + (old_crtc_state) = > intel_atomic_get_old_crtc_state((__state), (crtc)), \ > + (new_crtc_state) = > intel_atomic_get_new_crtc_state((__state), (crtc)))) > > #define for_each_oldnew_intel_crtc_in_state_reverse(__state, crtc, > old_crtc_state, new_crtc_state, __i) \ > - for ((__i) = (__state)->base.dev->mode_config.num_crtc - 1; \ > - (__i) >= 0 && \ > - ((crtc) = to_intel_crtc((__state)->base.crtcs[__i].ptr), \ > - (old_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].old_state), \ > - (new_crtc_state) = > to_intel_crtc_state((__state)->base.crtcs[__i].new_state), 1); \ > - (__i)--) \ > - for_each_if(crtc) > + for_each_intel_crtc_reverse((__state)->base.dev, (crtc)) \ > + for_each_if(((__i) = drm_crtc_index(&(crtc)->base), > (void)(__i), \ > + (old_crtc_state) = > intel_atomic_get_old_crtc_state((__state), (crtc)), \ > + (new_crtc_state) = > intel_atomic_get_new_crtc_state((__state), (crtc)))) These were a PITA to go through, but I think it's fine. Knocks wood. Thanks for doing this. Reviewed-by: Jani Nikula <[email protected]> > > #define intel_atomic_crtc_state_for_each_plane_state( \ > plane, plane_state, \ > diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h > b/drivers/gpu/drm/i915/display/intel_display_core.h > index 9b8414b77c15..4f4d5c314394 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_core.h > +++ b/drivers/gpu/drm/i915/display/intel_display_core.h > @@ -294,6 +294,9 @@ struct intel_display { > /* Parent, or core, driver functions exposed to display */ > const struct intel_display_parent_interface *parent; > > + /* list of all intel_crtcs sorted by pipe */ > + struct list_head pipe_list; > + > /* Display functions */ > struct { > /* Top level crtc-ish functions */ > diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c > b/drivers/gpu/drm/i915/display/intel_display_driver.c > index 7e000ba3e08b..32726906e550 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_driver.c > +++ b/drivers/gpu/drm/i915/display/intel_display_driver.c > @@ -119,6 +119,7 @@ static void intel_mode_config_init(struct intel_display > *display) > > drm_mode_config_init(display->drm); > INIT_LIST_HEAD(&display->global.obj_list); > + INIT_LIST_HEAD(&display->pipe_list); > > mode_config->min_width = 0; > mode_config->min_height = 0; > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h > b/drivers/gpu/drm/i915/display/intel_display_types.h > index 38702a9e0f50..1c2bd9445795 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > @@ -1441,6 +1441,7 @@ struct intel_flipq { > > struct intel_crtc { > struct drm_crtc base; > + struct list_head pipe_head; > enum pipe pipe; > /* > * Whether the crtc and the connected output pipeline is active. Implies > diff --git a/drivers/gpu/drm/xe/display/xe_display.c > b/drivers/gpu/drm/xe/display/xe_display.c > index e3320d9e6314..cfcbc7dd8638 100644 > --- a/drivers/gpu/drm/xe/display/xe_display.c > +++ b/drivers/gpu/drm/xe/display/xe_display.c > @@ -22,6 +22,7 @@ > #include "intel_audio.h" > #include "intel_bw.h" > #include "intel_display.h" > +#include "intel_display_core.h" > #include "intel_display_device.h" > #include "intel_display_driver.h" > #include "intel_display_irq.h" -- Jani Nikula, Intel
