> -----Original Message----- > From: Ander Conselvan De Oliveira [mailto:conselvan2@xxxxxxxxx] > Sent: Friday, May 6, 2016 6:38 PM > To: R, Durgadoss <durgadoss.r@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCHv4 1/3] drm/i915: Make finding unused crtc as > a generic function > > On Mon, 2016-04-18 at 19:01 +0530, Durgadoss R wrote: > > Looping over the crtc list and finding an unused crtc has other users > > like upfront link training. Hence move it to > > "will have", since this patch precedes the upfront link training one. > > > a common function to re-use the logic. > > > > v4: > > * Added ERR_PTR as a return value in kernel Doc comment (Ander) > > v3: > > * Added kernel Doc and removed an invalid comment (Ander) > > * Rebased on top of latest code which includes locking > > for state->enable usage. > > v2: > > * Made this as a separate function instead of having it > > inside upfront link train code. > > > > Signed-off-by: Durgadoss R <durgadoss.r@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_display.c | 74 > > +++++++++++++++++++++------------ > > --- > > drivers/gpu/drm/i915/intel_drv.h | 2 + > > 2 files changed, 45 insertions(+), 31 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_display.c > > b/drivers/gpu/drm/i915/intel_display.c > > index 4cca155..a6df48b 100644 > > --- a/drivers/gpu/drm/i915/intel_display.c > > +++ b/drivers/gpu/drm/i915/intel_display.c > > @@ -10404,6 +10404,43 @@ static int > > intel_modeset_setup_plane_state(struct > > drm_atomic_state *state, > > return 0; > > } > > > > +/** > > + * intel_get_unused_crtc - Find an unused crtc for the given encoder > > + * @encoder: drm_encoder structure > > + * @ctx: ctx pointer to use with locking > > + * > > + * This function tries to find an unused crtc that can drive > > + * the given encoder. Returns NULL or ERR_PTR on failure. > > This NULL or ERR_PTR makes for an awkward interface. I wonder if it should > just return ERR_PTR(-EBUSY) or even ERR_PTR(-EINVAL) if there is no free > crtc. It's no big deal though. > > Also, in the success case crtc->mutex is kept locked. That should be added to > the documentation above. > Ok, Will make the failure case as return (-EINVAL). > > + */ > > +struct drm_crtc *intel_get_unused_crtc(struct drm_encoder *encoder, > > + struct drm_modeset_acquire_ctx *ctx) { > > + struct drm_crtc *possible_crtc; > > + struct drm_crtc *crtc = NULL; > > + struct drm_device *dev = encoder->dev; > > + int ret, i = -1; > > + > > + for_each_crtc(dev, possible_crtc) { > > + i++; > > + if (!(encoder->possible_crtcs & (1 << i))) > > + continue; > > + > > + ret = drm_modeset_lock(&possible_crtc->mutex, ctx); > > + if (ret) > > + return ERR_PTR(ret); > > + > > + if (possible_crtc->state->enable) { > > + drm_modeset_unlock(&possible_crtc->mutex); > > + continue; > > + } > > + > > + crtc = possible_crtc; > > + break; > > This could be replaced with "return possible_crtc;". No need for the extra > assignment and break. > > I see that in patch 3 you have a debug message for when this returns NULL. It > would make sense to move that debug here. Sure, will add it here.. Thanks, Durga > > Ander > > > + } > > + > > + return crtc; > > +} > > + > > bool intel_get_load_detect_pipe(struct drm_connector *connector, > > struct drm_display_mode *mode, > > struct intel_load_detect_pipe *old, @@ - > 10412,7 +10449,6 @@ bool > > intel_get_load_detect_pipe(struct drm_connector *connector, > > struct intel_crtc *intel_crtc; > > struct intel_encoder *intel_encoder = > > intel_attached_encoder(connector); > > - struct drm_crtc *possible_crtc; > > struct drm_encoder *encoder = &intel_encoder->base; > > struct drm_crtc *crtc = NULL; > > struct drm_device *dev = encoder->dev; @@ -10421,7 +10457,7 @@ > bool > > intel_get_load_detect_pipe(struct drm_connector *connector, > > struct drm_atomic_state *state = NULL, *restore_state = NULL; > > struct drm_connector_state *connector_state; > > struct intel_crtc_state *crtc_state; > > - int ret, i = -1; > > + int ret; > > > > DRM_DEBUG_KMS("[CONNECTOR:%d:%s], [ENCODER:%d:%s]\n", > > connector->base.id, connector->name, @@ -10451,39 > +10487,15 > > @@ retry: > > ret = drm_modeset_lock(&crtc->mutex, ctx); > > if (ret) > > goto fail; > > - > > - /* Make sure the crtc and connector are running */ > > - goto found; > > - } > > - > > - /* Find an unused one (if possible) */ > > - for_each_crtc(dev, possible_crtc) { > > - i++; > > - if (!(encoder->possible_crtcs & (1 << i))) > > - continue; > > - > > - ret = drm_modeset_lock(&possible_crtc->mutex, ctx); > > - if (ret) > > + } else { > > + crtc = intel_get_unused_crtc(encoder, ctx); > > + if (IS_ERR_OR_NULL(crtc)) { > > + ret = PTR_ERR_OR_ZERO(crtc); > > + DRM_DEBUG_KMS("no pipe available for load- > detect\n"); > > goto fail; > > - > > - if (possible_crtc->state->enable) { > > - drm_modeset_unlock(&possible_crtc->mutex); > > - continue; > > } > > - > > - crtc = possible_crtc; > > - break; > > - } > > - > > - /* > > - * If we didn't find an unused CRTC, don't use any. > > - */ > > - if (!crtc) { > > - DRM_DEBUG_KMS("no pipe available for load-detect\n"); > > - goto fail; > > } > > > > -found: > > intel_crtc = to_intel_crtc(crtc); > > > > ret = drm_modeset_lock(&crtc->primary->mutex, ctx); diff --git > > a/drivers/gpu/drm/i915/intel_drv.h > > b/drivers/gpu/drm/i915/intel_drv.h > > index e13ce22..27b5dcd 100644 > > --- a/drivers/gpu/drm/i915/intel_drv.h > > +++ b/drivers/gpu/drm/i915/intel_drv.h > > @@ -1159,6 +1159,8 @@ bool intel_get_load_detect_pipe(struct > > drm_connector *connector, > > void intel_release_load_detect_pipe(struct drm_connector *connector, > > struct intel_load_detect_pipe *old, > > struct drm_modeset_acquire_ctx *ctx); > > +struct drm_crtc *intel_get_unused_crtc(struct drm_encoder *encoder, > > + struct drm_modeset_acquire_ctx *ctx); > > int intel_pin_and_fence_fb_obj(struct drm_framebuffer *fb, > > unsigned int rotation); > > struct drm_framebuffer * _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
