Op 29-06-17 om 13:00 schreef Daniel Vetter:
On Thu, Jun 29, 2017 at 12:58 PM, Maarten Lankhorst maarten.lankhorst@linux.intel.com wrote:
Op 29-06-17 om 12:31 schreef Daniel Vetter:
On Thu, Jun 29, 2017 at 12:22 PM, Maarten Lankhorst maarten.lankhorst@linux.intel.com wrote:
+static void dpms_atomic(struct drm_fb_helper *fb_helper, int dpms_mode) +{
struct drm_device *dev = fb_helper->dev;struct drm_atomic_state *state;int i, ret;struct drm_modeset_acquire_ctx ctx;drm_modeset_acquire_init(&ctx, 0);state = drm_atomic_state_alloc(dev);if (!state) {ret = -ENOMEM;goto out_ctx;}state->acquire_ctx = &ctx;+retry:
for (i = 0; i < fb_helper->crtc_count; i++) {struct drm_crtc_state *crtc_state;struct drm_crtc *crtc;if (!fb_helper->crtc_info[i].mode_set.mode)continue;crtc = fb_helper->crtc_info[i].mode_set.crtc;crtc_state = drm_atomic_get_crtc_state(state, crtc);if (IS_ERR(crtc_state)) {ret = PTR_ERR(crtc_state);goto out_state;}Hm, maybe remove the early continue, and change this to if (crtc_state->enable) crtc_state->active = ...; ?
I don't know if it matters in practice, but it might be more resilient when crtc state does not match our expected state, similar to how DPMS on is ignored without CRTC.
I just blindly smashed the old fbdev code in with the helper and moved the locking out. Not sure what would be better here, since the continue is in a way just part of a non-existent drm_fb_helper_for_each_active_crtc loop iterator. Not sure it's worth it to overpolish this code to such an extent :-) -Daniel
Well checking for crtc_state->enable instead of mode_set.mode probably means we're at least bug for bug compatible vs legacy. It might be better to add a bool active to restore_fbdev_mode_atomic.
What about something like this? The less atomic commits the better. :)
Hm yeah, that sounds like a useful simplification. I don't think we should do too much into extremes in fbdev and only have 1 atomic commit, because fbdev fundamentally isn't atomic. But merging them where it makes sense is reasonable. -Daniel
Agreed, perhaps with pan_display_atomic too, if we no longer use modeset locks, then it becomes very simple.. What about getting rid of that one too, in favor of this?
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 0cd2035ac1d1..b4356fdf5e6d 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1557,70 +1557,36 @@ int drm_fb_helper_set_par(struct fb_info *info) } EXPORT_SYMBOL(drm_fb_helper_set_par);
-static int pan_display_atomic(struct fb_var_screeninfo *var, - struct fb_info *info) +static void pan_set(struct drm_fb_helper *fb_helper, int x, int y) { - struct drm_fb_helper *fb_helper = info->par; - struct drm_device *dev = fb_helper->dev; - struct drm_atomic_state *state; - struct drm_plane *plane; - int i, ret; - unsigned int plane_mask; - struct drm_modeset_acquire_ctx ctx; - - drm_modeset_acquire_init(&ctx, 0); - - state = drm_atomic_state_alloc(dev); - if (!state) { - ret = -ENOMEM; - goto out_ctx; - } + int i;
- state->acquire_ctx = &ctx; -retry: - plane_mask = 0; for (i = 0; i < fb_helper->crtc_count; i++) { struct drm_mode_set *mode_set;
mode_set = &fb_helper->crtc_info[i].mode_set;
- mode_set->x = var->xoffset; - mode_set->y = var->yoffset; - - ret = __drm_atomic_helper_set_config(mode_set, state); - if (ret != 0) - goto out_state; - - plane = mode_set->crtc->primary; - plane_mask |= (1 << drm_plane_index(plane)); - plane->old_fb = plane->fb; + mode_set->x = x; + mode_set->y = y; } +}
- ret = drm_atomic_commit(state); - if (ret != 0) - goto out_state; - - info->var.xoffset = var->xoffset; - info->var.yoffset = var->yoffset; +static int pan_display_atomic(struct fb_var_screeninfo *var, + struct fb_info *info) +{ + struct drm_fb_helper *fb_helper = info->par; + int ret;
-out_state: - drm_atomic_clean_old_fb(dev, plane_mask, ret); + pan_set(fb_helper, var->xoffset, var->yoffset);
- if (ret == -EDEADLK) - goto backoff; - - drm_atomic_state_put(state); -out_ctx: - drm_modeset_drop_locks(&ctx); - drm_modeset_acquire_fini(&ctx); + ret = restore_fbdev_mode(fb_helper); + if (!ret) { + info->var.xoffset = var->xoffset; + info->var.yoffset = var->yoffset; + } else + pan_set(fb_helper, info->var.xoffset, info->var.yoffset);
return ret; - -backoff: - drm_atomic_state_clear(state); - drm_modeset_backoff(&ctx); - - goto retry; }
static int pan_display_legacy(struct fb_var_screeninfo *var,