diff options
Diffstat (limited to 'drivers/gpu/drm/rcar-du/rcar_du_kms.c')
| -rw-r--r-- | drivers/gpu/drm/rcar-du/rcar_du_kms.c | 349 |
1 files changed, 319 insertions, 30 deletions
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/rcar-du/rcar_du_kms.c index 68dab2601bf5..93117f159a3b 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c @@ -12,12 +12,15 @@ */ #include <drm/drmP.h> +#include <drm/drm_atomic.h> +#include <drm/drm_atomic_helper.h> #include <drm/drm_crtc.h> #include <drm/drm_crtc_helper.h> #include <drm/drm_fb_cma_helper.h> #include <drm/drm_gem_cma_helper.h> #include <linux/of_graph.h> +#include <linux/wait.h> #include "rcar_du_crtc.h" #include "rcar_du_drv.h" @@ -185,9 +188,309 @@ static void rcar_du_output_poll_changed(struct drm_device *dev) drm_fbdev_cma_hotplug_event(rcdu->fbdev); } +/* ----------------------------------------------------------------------------- + * Atomic Check and Update + */ + +/* + * Atomic hardware plane allocator + * + * The hardware plane allocator is solely based on the atomic plane states + * without keeping any external state to avoid races between .atomic_check() + * and .atomic_commit(). + * + * The core idea is to avoid using a free planes bitmask that would need to be + * shared between check and commit handlers with a collective knowledge based on + * the allocated hardware plane(s) for each KMS plane. The allocator then loops + * over all plane states to compute the free planes bitmask, allocates hardware + * planes based on that bitmask, and stores the result back in the plane states. + * + * For this to work we need to access the current state of planes not touched by + * the atomic update. To ensure that it won't be modified, we need to lock all + * planes using drm_atomic_get_plane_state(). This effectively serializes atomic + * updates from .atomic_check() up to completion (when swapping the states if + * the check step has succeeded) or rollback (when freeing the states if the + * check step has failed). + * + * Allocation is performed in the .atomic_check() handler and applied + * automatically when the core swaps the old and new states. + */ + +static bool rcar_du_plane_needs_realloc(struct rcar_du_plane *plane, + struct rcar_du_plane_state *state) +{ + const struct rcar_du_format_info *cur_format; + + cur_format = to_rcar_du_plane_state(plane->plane.state)->format; + + /* Lowering the number of planes doesn't strictly require reallocation + * as the extra hardware plane will be freed when committing, but doing + * so could lead to more fragmentation. + */ + return !cur_format || cur_format->planes != state->format->planes; +} + +static unsigned int rcar_du_plane_hwmask(struct rcar_du_plane_state *state) +{ + unsigned int mask; + + if (state->hwindex == -1) + return 0; + + mask = 1 << state->hwindex; + if (state->format->planes == 2) + mask |= 1 << ((state->hwindex + 1) % 8); + + return mask; +} + +static int rcar_du_plane_hwalloc(unsigned int num_planes, unsigned int free) +{ + unsigned int i; + + for (i = 0; i < RCAR_DU_NUM_HW_PLANES; ++i) { + if (!(free & (1 << i))) + continue; + + if (num_planes == 1 || free & (1 << ((i + 1) % 8))) + break; + } + + return i == RCAR_DU_NUM_HW_PLANES ? -EBUSY : i; +} + +static int rcar_du_atomic_check(struct drm_device *dev, + struct drm_atomic_state *state) +{ + struct rcar_du_device *rcdu = dev->dev_private; + unsigned int group_freed_planes[RCAR_DU_MAX_GROUPS] = { 0, }; + unsigned int group_free_planes[RCAR_DU_MAX_GROUPS] = { 0, }; + bool needs_realloc = false; + unsigned int groups = 0; + unsigned int i; + int ret; + + ret = drm_atomic_helper_check(dev, state); + if (ret < 0) + return ret; + + /* Check if hardware planes need to be reallocated. */ + for (i = 0; i < dev->mode_config.num_total_plane; ++i) { + struct rcar_du_plane_state *plane_state; + struct rcar_du_plane *plane; + unsigned int index; + + if (!state->planes[i]) + continue; + + plane = to_rcar_plane(state->planes[i]); + plane_state = to_rcar_du_plane_state(state->plane_states[i]); + + /* If the plane is being disabled we don't need to go through + * the full reallocation procedure. Just mark the hardware + * plane(s) as freed. + */ + if (!plane_state->format) { + index = plane - plane->group->planes.planes; + group_freed_planes[plane->group->index] |= 1 << index; + plane_state->hwindex = -1; + continue; + } + + /* If the plane needs to be reallocated mark it as such, and + * mark the hardware plane(s) as free. + */ + if (rcar_du_plane_needs_realloc(plane, plane_state)) { + groups |= 1 << plane->group->index; + needs_realloc = true; + + index = plane - plane->group->planes.planes; + group_freed_planes[plane->group->index] |= 1 << index; + plane_state->hwindex = -1; + } + } + + if (!needs_realloc) + return 0; + + /* Grab all plane states for the groups that need reallocation to ensure + * locking and avoid racy updates. This serializes the update operation, + * but there's not much we can do about it as that's the hardware + * design. + * + * Compute the used planes mask for each group at the same time to avoid + * looping over the planes separately later. + */ + while (groups) { + unsigned int index = ffs(groups) - 1; + struct rcar_du_group *group = &rcdu->groups[index]; + unsigned int used_planes = 0; + + for (i = 0; i < RCAR_DU_NUM_KMS_PLANES; ++i) { + struct rcar_du_plane *plane = &group->planes.planes[i]; + struct rcar_du_plane_state *plane_state; + struct drm_plane_state *s; + + s = drm_atomic_get_plane_state(state, &plane->plane); + if (IS_ERR(s)) + return PTR_ERR(s); + + /* If the plane has been freed in the above loop its + * hardware planes must not be added to the used planes + * bitmask. However, the current state doesn't reflect + * the free state yet, as we've modified the new state + * above. Use the local freed planes list to check for + * that condition instead. + */ + if (group_freed_planes[index] & (1 << i)) + continue; + + plane_state = to_rcar_du_plane_state(plane->plane.state); + used_planes |= rcar_du_plane_hwmask(plane_state); + } + + group_free_planes[index] = 0xff & ~used_planes; + groups &= ~(1 << index); + } + + /* Reallocate hardware planes for each plane that needs it. */ + for (i = 0; i < dev->mode_config.num_total_plane; ++i) { + struct rcar_du_plane_state *plane_state; + struct rcar_du_plane *plane; + int idx; + + if (!state->planes[i]) + continue; + + plane = to_rcar_plane(state->planes[i]); + plane_state = to_rcar_du_plane_state(state->plane_states[i]); + + /* Skip planes that are being disabled or don't need to be + * reallocated. + */ + if (!plane_state->format || + !rcar_du_plane_needs_realloc(plane, plane_state)) + continue; + + idx = rcar_du_plane_hwalloc(plane_state->format->planes, + group_free_planes[plane->group->index]); + if (idx < 0) { + dev_dbg(rcdu->dev, "%s: no available hardware plane\n", + __func__); + return idx; + } + + plane_state->hwindex = idx; + + group_free_planes[plane->group->index] &= + ~rcar_du_plane_hwmask(plane_state); + } + + return 0; +} + +struct rcar_du_commit { + struct work_struct work; + struct drm_device *dev; + struct drm_atomic_state *state; + u32 crtcs; +}; + +static void rcar_du_atomic_complete(struct rcar_du_commit *commit) +{ + struct drm_device *dev = commit->dev; + struct rcar_du_device *rcdu = dev->dev_private; + struct drm_atomic_state *old_state = commit->state; + + /* Apply the atomic update. */ + drm_atomic_helper_commit_modeset_disables(dev, old_state); + drm_atomic_helper_commit_modeset_enables(dev, old_state); + drm_atomic_helper_commit_planes(dev, old_state); + + drm_atomic_helper_wait_for_vblanks(dev, old_state); + + drm_atomic_helper_cleanup_planes(dev, old_state); + + drm_atomic_state_free(old_state); + + /* Complete the commit, wake up any waiter. */ + spin_lock(&rcdu->commit.wait.lock); + rcdu->commit.pending &= ~commit->crtcs; + wake_up_all_locked(&rcdu->commit.wait); + spin_unlock(&rcdu->commit.wait.lock); + + kfree(commit); +} + +static void rcar_du_atomic_work(struct work_struct *work) +{ + struct rcar_du_commit *commit = + container_of(work, struct rcar_du_commit, work); + + rcar_du_atomic_complete(commit); +} + +static int rcar_du_atomic_commit(struct drm_device *dev, + struct drm_atomic_state *state, bool async) +{ + struct rcar_du_device *rcdu = dev->dev_private; + struct rcar_du_commit *commit; + unsigned int i; + int ret; + + ret = drm_atomic_helper_prepare_planes(dev, state); + if (ret) + return ret; + + /* Allocate the commit object. */ + commit = kzalloc(sizeof(*commit), GFP_KERNEL); + if (commit == NULL) + return -ENOMEM; + + INIT_WORK(&commit->work, rcar_du_atomic_work); + commit->dev = dev; + commit->state = state; + + /* Wait until all affected CRTCs have completed previous commits and + * mark them as pending. + */ + for (i = 0; i < dev->mode_config.num_crtc; ++i) { + if (state->crtcs[i]) + commit->crtcs |= 1 << drm_crtc_index(state->crtcs[i]); + } + + spin_lock(&rcdu->commit.wait.lock); + ret = wait_event_interruptible_locked(rcdu->commit.wait, + !(rcdu->commit.pending & commit->crtcs)); + if (ret == 0) + rcdu->commit.pending |= commit->crtcs; + spin_unlock(&rcdu->commit.wait.lock); + + if (ret) { + kfree(commit); + return ret; + } + + /* Swap the state, this is the point of no return. */ + drm_atomic_helper_swap_state(dev, state); + + if (async) + schedule_work(&commit->work); + else + rcar_du_atomic_complete(commit); + + return 0; +} + +/* ----------------------------------------------------------------------------- + * Initialization + */ + static const struct drm_mode_config_funcs rcar_du_mode_config_funcs = { .fb_create = rcar_du_fb_create, .output_poll_changed = rcar_du_output_poll_changed, + .atomic_check = rcar_du_atomic_check, + .atomic_commit = rcar_du_atomic_commit, }; static int rcar_du_encoders_init_one(struct rcar_du_device *rcdu, @@ -224,12 +527,7 @@ static int rcar_du_encoders_init_one(struct rcar_du_device *rcdu, entity_ep_node = of_parse_phandle(ep->local_node, "remote-endpoint", 0); - while (1) { - ep_node = of_graph_get_next_endpoint(entity, ep_node); - - if (!ep_node) - break; - + for_each_endpoint_of_node(entity, ep_node) { if (ep_node == entity_ep_node) continue; @@ -296,24 +594,19 @@ static int rcar_du_encoders_init_one(struct rcar_du_device *rcdu, static int rcar_du_encoders_init(struct rcar_du_device *rcdu) { struct device_node *np = rcdu->dev->of_node; - struct device_node *ep_node = NULL; + struct device_node *ep_node; unsigned int num_encoders = 0; /* * Iterate over the endpoints and create one encoder for each output * pipeline. */ - while (1) { + for_each_endpoint_of_node(np, ep_node) { enum rcar_du_output output; struct of_endpoint ep; unsigned int i; int ret; - ep_node = of_graph_get_next_endpoint(np, ep_node); - - if (ep_node == NULL) - break; - ret = of_graph_parse_endpoint(ep_node, &ep); if (ret < 0) { of_node_put(ep_node); @@ -385,6 +678,8 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu) for (i = 0; i < num_groups; ++i) { struct rcar_du_group *rgrp = &rcdu->groups[i]; + mutex_init(&rgrp->lock); + rgrp->dev = rcdu; rgrp->mmio_offset = mmio_offsets[i]; rgrp->index = i; @@ -432,27 +727,21 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu) encoder->possible_clones = (1 << num_encoders) - 1; } - /* Now that the CRTCs have been initialized register the planes. */ - for (i = 0; i < num_groups; ++i) { - ret = rcar_du_planes_register(&rcdu->groups[i]); - if (ret < 0) - return ret; - } + drm_mode_config_reset(dev); drm_kms_helper_poll_init(dev); - drm_helper_disable_unused_functions(dev); + if (dev->mode_config.num_connector) { + fbdev = drm_fbdev_cma_init(dev, 32, dev->mode_config.num_crtc, + dev->mode_config.num_connector); + if (IS_ERR(fbdev)) + return PTR_ERR(fbdev); - fbdev = drm_fbdev_cma_init(dev, 32, dev->mode_config.num_crtc, - dev->mode_config.num_connector); - if (IS_ERR(fbdev)) - return PTR_ERR(fbdev); - -#ifndef CONFIG_FRAMEBUFFER_CONSOLE - drm_fbdev_cma_restore_mode(fbdev); -#endif - - rcdu->fbdev = fbdev; + rcdu->fbdev = fbdev; + } else { + dev_info(rcdu->dev, + "no connector found, disabling fbdev emulation\n"); + } return 0; } |