diff options
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_drv.c | 1 | ||||
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_drv.h | 11 | ||||
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_kms.c | 103 | ||||
| -rw-r--r-- | drivers/gpu/drm/vc4/vc4_plane.c | 57 |
4 files changed, 171 insertions, 1 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 52576dee809e..3227706700f9 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -311,6 +311,7 @@ static void vc4_drm_unbind(struct device *dev) drm_mode_config_cleanup(drm); + drm_atomic_private_obj_fini(&vc4->load_tracker); drm_atomic_private_obj_fini(&vc4->ctm_manager); drm_dev_put(drm); diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h index 6f86af1b3212..bbab084911f3 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -207,6 +207,7 @@ struct vc4_dev { struct drm_modeset_lock ctm_state_lock; struct drm_private_obj ctm_manager; + struct drm_private_obj load_tracker; }; static inline struct vc4_dev * @@ -378,6 +379,16 @@ struct vc4_plane_state { * when async update is not possible. */ bool dlist_initialized; + + /* Load of this plane on the HVS block. The load is expressed in HVS + * cycles/sec. + */ + u64 hvs_load; + + /* Memory bandwidth needed for this plane. This is expressed in + * bytes/sec. + */ + u64 membus_load; }; static inline struct vc4_plane_state * diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c index b971258dcfd4..6e20604573de 100644 --- a/drivers/gpu/drm/vc4/vc4_kms.c +++ b/drivers/gpu/drm/vc4/vc4_kms.c @@ -34,6 +34,18 @@ static struct vc4_ctm_state *to_vc4_ctm_state(struct drm_private_state *priv) return container_of(priv, struct vc4_ctm_state, base); } +struct vc4_load_tracker_state { + struct drm_private_state base; + u64 hvs_load; + u64 membus_load; +}; + +static struct vc4_load_tracker_state * +to_vc4_load_tracker_state(struct drm_private_state *priv) +{ + return container_of(priv, struct vc4_load_tracker_state, base); +} + static struct vc4_ctm_state *vc4_get_ctm_state(struct drm_atomic_state *state, struct drm_private_obj *manager) { @@ -395,6 +407,81 @@ vc4_ctm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state) return 0; } +static int vc4_load_tracker_atomic_check(struct drm_atomic_state *state) +{ + struct drm_plane_state *old_plane_state, *new_plane_state; + struct vc4_dev *vc4 = to_vc4_dev(state->dev); + struct vc4_load_tracker_state *load_state; + struct drm_private_state *priv_state; + struct drm_plane *plane; + int i; + + priv_state = drm_atomic_get_private_obj_state(state, + &vc4->load_tracker); + if (IS_ERR(priv_state)) + return PTR_ERR(priv_state); + + load_state = to_vc4_load_tracker_state(priv_state); + for_each_oldnew_plane_in_state(state, plane, old_plane_state, + new_plane_state, i) { + struct vc4_plane_state *vc4_plane_state; + + if (old_plane_state->fb && old_plane_state->crtc) { + vc4_plane_state = to_vc4_plane_state(old_plane_state); + load_state->membus_load -= vc4_plane_state->membus_load; + load_state->hvs_load -= vc4_plane_state->hvs_load; + } + + if (new_plane_state->fb && new_plane_state->crtc) { + vc4_plane_state = to_vc4_plane_state(new_plane_state); + load_state->membus_load += vc4_plane_state->membus_load; + load_state->hvs_load += vc4_plane_state->hvs_load; + } + } + + /* The absolute limit is 2Gbyte/sec, but let's take a margin to let + * the system work when other blocks are accessing the memory. + */ + if (load_state->membus_load > SZ_1G + SZ_512M) + return -ENOSPC; + + /* HVS clock is supposed to run @ 250Mhz, let's take a margin and + * consider the maximum number of cycles is 240M. + */ + if (load_state->hvs_load > 240000000ULL) + return -ENOSPC; + + return 0; +} + +static struct drm_private_state * +vc4_load_tracker_duplicate_state(struct drm_private_obj *obj) +{ + struct vc4_load_tracker_state *state; + + state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL); + if (!state) + return NULL; + + __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base); + + return &state->base; +} + +static void vc4_load_tracker_destroy_state(struct drm_private_obj *obj, + struct drm_private_state *state) +{ + struct vc4_load_tracker_state *load_state; + + load_state = to_vc4_load_tracker_state(state); + kfree(load_state); +} + +static const struct drm_private_state_funcs vc4_load_tracker_state_funcs = { + .atomic_duplicate_state = vc4_load_tracker_duplicate_state, + .atomic_destroy_state = vc4_load_tracker_destroy_state, +}; + static int vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state) { @@ -404,7 +491,11 @@ vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state) if (ret < 0) return ret; - return drm_atomic_helper_check(dev, state); + ret = drm_atomic_helper_check(dev, state); + if (ret) + return ret; + + return vc4_load_tracker_atomic_check(state); } static const struct drm_mode_config_funcs vc4_mode_funcs = { @@ -417,6 +508,7 @@ int vc4_kms_load(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev); struct vc4_ctm_state *ctm_state; + struct vc4_load_tracker_state *load_state; int ret; sema_init(&vc4->async_modeset, 1); @@ -446,6 +538,15 @@ int vc4_kms_load(struct drm_device *dev) drm_atomic_private_obj_init(dev, &vc4->ctm_manager, &ctm_state->base, &vc4_ctm_state_funcs); + load_state = kzalloc(sizeof(*load_state), GFP_KERNEL); + if (!load_state) { + drm_atomic_private_obj_fini(&vc4->ctm_manager); + return -ENOMEM; + } + + drm_atomic_private_obj_init(dev, &vc4->load_tracker, &load_state->base, + &vc4_load_tracker_state_funcs); + drm_mode_config_reset(dev); drm_kms_helper_poll_init(dev); diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c index 1babfeca0c92..4d918d3e4858 100644 --- a/drivers/gpu/drm/vc4/vc4_plane.c +++ b/drivers/gpu/drm/vc4/vc4_plane.c @@ -488,6 +488,61 @@ static void vc4_write_scaling_parameters(struct drm_plane_state *state, } } +static void vc4_plane_calc_load(struct drm_plane_state *state) +{ + unsigned int hvs_load_shift, vrefresh, i; + struct drm_framebuffer *fb = state->fb; + struct vc4_plane_state *vc4_state; + struct drm_crtc_state *crtc_state; + unsigned int vscale_factor; + + vc4_state = to_vc4_plane_state(state); + crtc_state = drm_atomic_get_existing_crtc_state(state->state, + state->crtc); + vrefresh = drm_mode_vrefresh(&crtc_state->adjusted_mode); + + /* The HVS is able to process 2 pixels/cycle when scaling the source, + * 4 pixels/cycle otherwise. + * Alpha blending step seems to be pipelined and it's always operating + * at 4 pixels/cycle, so the limiting aspect here seems to be the + * scaler block. + * HVS load is expressed in clk-cycles/sec (AKA Hz). + */ + if (vc4_state->x_scaling[0] != VC4_SCALING_NONE || + vc4_state->x_scaling[1] != VC4_SCALING_NONE || + vc4_state->y_scaling[0] != VC4_SCALING_NONE || + vc4_state->y_scaling[1] != VC4_SCALING_NONE) + hvs_load_shift = 1; + else + hvs_load_shift = 2; + + vc4_state->membus_load = 0; + vc4_state->hvs_load = 0; + for (i = 0; i < fb->format->num_planes; i++) { + /* Even if the bandwidth/plane required for a single frame is + * + * vc4_state->src_w[i] * vc4_state->src_h[i] * cpp * vrefresh + * + * when downscaling, we have to read more pixels per line in + * the time frame reserved for a single line, so the bandwidth + * demand can be punctually higher. To account for that, we + * calculate the down-scaling factor and multiply the plane + * load by this number. We're likely over-estimating the read + * demand, but that's better than under-estimating it. + */ + vscale_factor = DIV_ROUND_UP(vc4_state->src_h[i], + vc4_state->crtc_h); + vc4_state->membus_load += vc4_state->src_w[i] * + vc4_state->src_h[i] * vscale_factor * + fb->format->cpp[i]; + vc4_state->hvs_load += vc4_state->crtc_h * vc4_state->crtc_w; + } + + vc4_state->hvs_load *= vrefresh; + vc4_state->hvs_load >>= hvs_load_shift; + vc4_state->membus_load *= vrefresh; +} + static int vc4_plane_allocate_lbm(struct drm_plane_state *state) { struct vc4_dev *vc4 = to_vc4_dev(state->plane->dev); @@ -875,6 +930,8 @@ static int vc4_plane_mode_set(struct drm_plane *plane, */ vc4_state->dlist_initialized = 1; + vc4_plane_calc_load(state); + return 0; } |