Am 30.11.22 um 20:26 schrieb Noralf Trønnes via B4 Submission Endpoint: > From: Noralf Trønnes > > Use the shadow plane helper to take care of mapping the framebuffer for > CPU access. The synchronous flushing is now done inline without the use of > a worker. The async path now uses a shadow buffer to hold framebuffer > changes and it doesn't read the framebuffer behind userspace's back > anymore. > > v2: > - Use src as variable name for iosys_map (Thomas) > - Prepare imported buffer for CPU access in the driver (Thomas) > > Signed-off-by: Noralf Trønnes Reviewed-by: Thomas Zimmermann > --- > drivers/gpu/drm/gud/gud_drv.c | 1 + > drivers/gpu/drm/gud/gud_internal.h | 1 + > drivers/gpu/drm/gud/gud_pipe.c | 81 ++++++++++++++++++++++++++------------ > 3 files changed, 57 insertions(+), 26 deletions(-) > > diff --git a/drivers/gpu/drm/gud/gud_drv.c b/drivers/gpu/drm/gud/gud_drv.c > index d57dab104358..5aac7cda0505 100644 > --- a/drivers/gpu/drm/gud/gud_drv.c > +++ b/drivers/gpu/drm/gud/gud_drv.c > @@ -365,6 +365,7 @@ static void gud_debugfs_init(struct drm_minor *minor) > static const struct drm_simple_display_pipe_funcs gud_pipe_funcs = { > .check = gud_pipe_check, > .update = gud_pipe_update, > + DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS > }; > > static const struct drm_mode_config_funcs gud_mode_config_funcs = { > diff --git a/drivers/gpu/drm/gud/gud_internal.h b/drivers/gpu/drm/gud/gud_internal.h > index e351a1f1420d..0d148a6f27aa 100644 > --- a/drivers/gpu/drm/gud/gud_internal.h > +++ b/drivers/gpu/drm/gud/gud_internal.h > @@ -43,6 +43,7 @@ struct gud_device { > struct drm_framebuffer *fb; > struct drm_rect damage; > bool prev_flush_failed; > + void *shadow_buf; > }; > > static inline struct gud_device *to_gud_device(struct drm_device *drm) > diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c > index 98fe8efda4a9..92189474a7ed 100644 > --- a/drivers/gpu/drm/gud/gud_pipe.c > +++ b/drivers/gpu/drm/gud/gud_pipe.c > @@ -358,10 +358,10 @@ static void gud_flush_damage(struct gud_device *gdrm, struct drm_framebuffer *fb > void gud_flush_work(struct work_struct *work) > { > struct gud_device *gdrm = container_of(work, struct gud_device, work); > - struct iosys_map gem_map = { }, fb_map = { }; > + struct iosys_map shadow_map; > struct drm_framebuffer *fb; > struct drm_rect damage; > - int idx, ret; > + int idx; > > if (!drm_dev_enter(&gdrm->drm, &idx)) > return; > @@ -369,6 +369,7 @@ void gud_flush_work(struct work_struct *work) > mutex_lock(&gdrm->damage_lock); > fb = gdrm->fb; > gdrm->fb = NULL; > + iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf); > damage = gdrm->damage; > gud_clear_damage(gdrm); > mutex_unlock(&gdrm->damage_lock); > @@ -376,33 +377,33 @@ void gud_flush_work(struct work_struct *work) > if (!fb) > goto out; > > - ret = drm_gem_fb_vmap(fb, &gem_map, &fb_map); > - if (ret) > - goto fb_put; > + gud_flush_damage(gdrm, fb, &shadow_map, true, &damage); > > - ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); > - if (ret) > - goto vunmap; > - > - /* Imported buffers are assumed to be WriteCombined with uncached reads */ > - gud_flush_damage(gdrm, fb, &fb_map, !fb->obj[0]->import_attach, &damage); > - > - drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); > -vunmap: > - drm_gem_fb_vunmap(fb, &gem_map); > -fb_put: > drm_framebuffer_put(fb); > out: > drm_dev_exit(idx); > } > > -static void gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer *fb, > - struct drm_rect *damage) > +static int gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer *fb, > + const struct iosys_map *src, struct drm_rect *damage) > { > struct drm_framebuffer *old_fb = NULL; > + struct iosys_map shadow_map; > > mutex_lock(&gdrm->damage_lock); > > + if (!gdrm->shadow_buf) { > + gdrm->shadow_buf = vzalloc(fb->pitches[0] * fb->height); > + if (!gdrm->shadow_buf) { > + mutex_unlock(&gdrm->damage_lock); > + return -ENOMEM; > + } > + } > + > + iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf); > + iosys_map_incr(&shadow_map, drm_fb_clip_offset(fb->pitches[0], fb->format, damage)); > + drm_fb_memcpy(&shadow_map, fb->pitches, src, fb, damage); > + > if (fb != gdrm->fb) { > old_fb = gdrm->fb; > drm_framebuffer_get(fb); > @@ -420,6 +421,26 @@ static void gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer > > if (old_fb) > drm_framebuffer_put(old_fb); > + > + return 0; > +} > + > +static void gud_fb_handle_damage(struct gud_device *gdrm, struct drm_framebuffer *fb, > + const struct iosys_map *src, struct drm_rect *damage) > +{ > + int ret; > + > + if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE) > + drm_rect_init(damage, 0, 0, fb->width, fb->height); > + > + if (gud_async_flush) { > + ret = gud_fb_queue_damage(gdrm, fb, src, damage); > + if (ret != -ENOMEM) > + return; > + } > + > + /* Imported buffers are assumed to be WriteCombined with uncached reads */ > + gud_flush_damage(gdrm, fb, src, !fb->obj[0]->import_attach, damage); > } > > int gud_pipe_check(struct drm_simple_display_pipe *pipe, > @@ -544,10 +565,11 @@ void gud_pipe_update(struct drm_simple_display_pipe *pipe, > struct drm_device *drm = pipe->crtc.dev; > struct gud_device *gdrm = to_gud_device(drm); > struct drm_plane_state *state = pipe->plane.state; > + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state); > struct drm_framebuffer *fb = state->fb; > struct drm_crtc *crtc = &pipe->crtc; > struct drm_rect damage; > - int idx; > + int ret, idx; > > if (crtc->state->mode_changed || !crtc->state->enable) { > cancel_work_sync(&gdrm->work); > @@ -557,6 +579,8 @@ void gud_pipe_update(struct drm_simple_display_pipe *pipe, > gdrm->fb = NULL; > } > gud_clear_damage(gdrm); > + vfree(gdrm->shadow_buf); > + gdrm->shadow_buf = NULL; > mutex_unlock(&gdrm->damage_lock); > } > > @@ -572,14 +596,19 @@ void gud_pipe_update(struct drm_simple_display_pipe *pipe, > if (crtc->state->active_changed) > gud_usb_set_u8(gdrm, GUD_REQ_SET_DISPLAY_ENABLE, crtc->state->active); > > - if (drm_atomic_helper_damage_merged(old_state, state, &damage)) { > - if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE) > - drm_rect_init(&damage, 0, 0, fb->width, fb->height); > - gud_fb_queue_damage(gdrm, fb, &damage); > - if (!gud_async_flush) > - flush_work(&gdrm->work); > - } > + if (!fb) > + goto ctrl_disable; > > + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); > + if (ret) > + goto ctrl_disable; > + > + if (drm_atomic_helper_damage_merged(old_state, state, &damage)) > + gud_fb_handle_damage(gdrm, fb, &shadow_plane_state->data[0], &damage); > + > + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); > + > +ctrl_disable: > if (!crtc->state->enable) > gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 0); > > -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev