diff options
Diffstat (limited to 'drivers/gpu/arm/midgard/mali_kbase_dma_fence.c')
| -rwxr-xr-x | drivers/gpu/arm/midgard/mali_kbase_dma_fence.c | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/drivers/gpu/arm/midgard/mali_kbase_dma_fence.c b/drivers/gpu/arm/midgard/mali_kbase_dma_fence.c new file mode 100755 index 000000000000..29f3324a9ddd --- /dev/null +++ b/drivers/gpu/arm/midgard/mali_kbase_dma_fence.c @@ -0,0 +1,524 @@ +/* + * + * (C) COPYRIGHT 2011-2016 ARM Limited. All rights reserved. + * + * This program is free software and is provided to you under the terms of the + * GNU General Public License version 2 as published by the Free Software + * Foundation, and any use by you of this program is subject to the terms + * of such GNU licence. + * + * A copy of the licence is included with the program, and can also be obtained + * from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + * Boston, MA 02110-1301, USA. + * + */ + + + + +/* Include mali_kbase_dma_fence.h before checking for CONFIG_MALI_DMA_FENCE as + * it will be set there. + */ +#include "mali_kbase_dma_fence.h" + +#include <linux/atomic.h> +#include <linux/fence.h> +#include <linux/list.h> +#include <linux/lockdep.h> +#include <linux/mutex.h> +#include <linux/reservation.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/workqueue.h> +#include <linux/ww_mutex.h> + +#include <mali_kbase.h> + + +/* Spin lock protecting all Mali fences as fence->lock. */ +static DEFINE_SPINLOCK(kbase_dma_fence_lock); + + +static void +kbase_dma_fence_waiters_add(struct kbase_jd_atom *katom) +{ + struct kbase_context *kctx = katom->kctx; + + list_add_tail(&katom->queue, &kctx->dma_fence.waiting_resource); +} + +void +kbase_dma_fence_waiters_remove(struct kbase_jd_atom *katom) +{ + list_del(&katom->queue); +} + +static const char * +kbase_dma_fence_get_driver_name(struct fence *fence) +{ + return kbase_drv_name; +} + +static const char * +kbase_dma_fence_get_timeline_name(struct fence *fence) +{ + return kbase_timeline_name; +} + +static bool +kbase_dma_fence_enable_signaling(struct fence *fence) +{ + /* If in the future we need to add code here remember to + * to get a reference to the fence and release it when signaling + * as stated in fence.h + */ + return true; +} + +static void +kbase_dma_fence_fence_value_str(struct fence *fence, char *str, int size) +{ + snprintf(str, size, "%u", fence->seqno); +} + +static const struct fence_ops kbase_dma_fence_ops = { + .get_driver_name = kbase_dma_fence_get_driver_name, + .get_timeline_name = kbase_dma_fence_get_timeline_name, + .enable_signaling = kbase_dma_fence_enable_signaling, + /* Use the default wait */ + .wait = fence_default_wait, + .fence_value_str = kbase_dma_fence_fence_value_str, +}; + +static struct fence * +kbase_dma_fence_new(unsigned int context, unsigned int seqno) +{ + struct fence *fence; + + fence = kzalloc(sizeof(*fence), GFP_KERNEL); + if (!fence) + return NULL; + + fence_init(fence, + &kbase_dma_fence_ops, + &kbase_dma_fence_lock, + context, + seqno); + + return fence; +} + +static int +kbase_dma_fence_lock_reservations(struct kbase_dma_fence_resv_info *info, + struct ww_acquire_ctx *ctx) +{ + struct reservation_object *content_res = NULL; + unsigned int content_res_idx = 0; + unsigned int r; + int err; + + ww_acquire_init(ctx, &reservation_ww_class); + +retry: + for (r = 0; r < info->dma_fence_resv_count; r++) { + if (info->resv_objs[r] == content_res) { + content_res = NULL; + continue; + } + + err = ww_mutex_lock(&info->resv_objs[r]->lock, ctx); + if (err) + goto error; + } + + ww_acquire_done(ctx); + return err; + +error: + content_res_idx = r; + + /* Unlock the locked one ones */ + for (r--; r >= 0; r--) + ww_mutex_unlock(&info->resv_objs[r]->lock); + + if (content_res) + ww_mutex_unlock(&content_res->lock); + + /* If we deadlock try with lock_slow and retry */ + if (err == -EDEADLK) { + content_res = info->resv_objs[content_res_idx]; + ww_mutex_lock_slow(&content_res->lock, ctx); + goto retry; + } + + /* If we are here the function failed */ + ww_acquire_fini(ctx); + return err; +} + +static void +kbase_dma_fence_unlock_reservations(struct kbase_dma_fence_resv_info *info, + struct ww_acquire_ctx *ctx) +{ + unsigned int r; + + for (r = 0; r < info->dma_fence_resv_count; r++) + ww_mutex_unlock(&info->resv_objs[r]->lock); + ww_acquire_fini(ctx); +} + +/** + * kbase_dma_fence_free_callbacks - Free dma-fence callbacks on a katom + * @katom: Pointer to katom + * + * This function will free all fence callbacks on the katom's list of + * callbacks. Callbacks that have not yet been called, because their fence + * hasn't yet signaled, will first be removed from the fence. + * + * Locking: katom->dma_fence.callbacks list assumes jctx.lock is held. + */ +static void +kbase_dma_fence_free_callbacks(struct kbase_jd_atom *katom) +{ + struct kbase_dma_fence_cb *cb, *tmp; + + lockdep_assert_held(&katom->kctx->jctx.lock); + + /* Clean up and free callbacks. */ + list_for_each_entry_safe(cb, tmp, &katom->dma_fence.callbacks, node) { + bool ret; + + /* Cancel callbacks that hasn't been called yet. */ + ret = fence_remove_callback(cb->fence, &cb->fence_cb); + if (ret) { + /* Fence had not signaled, clean up after + * canceling. + */ + atomic_dec(&katom->dma_fence.dep_count); + } + + fence_put(cb->fence); + list_del(&cb->node); + kfree(cb); + } +} + +/** + * kbase_dma_fence_cancel_atom() - Cancels waiting on an atom + * @katom: Katom to cancel + * + * Locking: katom->dma_fence.callbacks list assumes jctx.lock is held. + */ +static void +kbase_dma_fence_cancel_atom(struct kbase_jd_atom *katom) +{ + lockdep_assert_held(&katom->kctx->jctx.lock); + + /* Cancel callbacks and clean up. */ + kbase_dma_fence_free_callbacks(katom); + + KBASE_DEBUG_ASSERT(atomic_read(&katom->dma_fence.dep_count) == 0); + + /* Mark the atom as handled in case all fences signaled just before + * canceling the callbacks and the worker was queued. + */ + atomic_set(&katom->dma_fence.dep_count, -1); + + /* Prevent job_done_nolock from being called twice on an atom when + * there is a race between job completion and cancellation. + */ + + if (katom->status == KBASE_JD_ATOM_STATE_QUEUED) { + /* Wait was cancelled - zap the atom */ + katom->event_code = BASE_JD_EVENT_JOB_CANCELLED; + if (jd_done_nolock(katom, NULL)) + kbase_js_sched_all(katom->kctx->kbdev); + } +} + +/** + * kbase_dma_fence_work() - Worker thread called when a fence is signaled + * @pwork: work_struct containing a pointer to a katom + * + * This function will clean and mark all dependencies as satisfied + */ +static void +kbase_dma_fence_work(struct work_struct *pwork) +{ + struct kbase_jd_atom *katom; + struct kbase_jd_context *ctx; + + katom = container_of(pwork, struct kbase_jd_atom, work); + ctx = &katom->kctx->jctx; + + mutex_lock(&ctx->lock); + if (atomic_read(&katom->dma_fence.dep_count) != 0) + goto out; + + atomic_set(&katom->dma_fence.dep_count, -1); + + /* Remove atom from list of dma-fence waiting atoms. */ + kbase_dma_fence_waiters_remove(katom); + /* Cleanup callbacks. */ + kbase_dma_fence_free_callbacks(katom); + /* Queue atom on GPU. */ + kbase_jd_dep_clear_locked(katom); + +out: + mutex_unlock(&ctx->lock); +} + +static int +kbase_dma_fence_add_callback(struct kbase_jd_atom *katom, + struct fence *fence, + fence_func_t callback) +{ + int err = 0; + struct kbase_dma_fence_cb *kbase_fence_cb; + + kbase_fence_cb = kmalloc(sizeof(*kbase_fence_cb), GFP_KERNEL); + if (!kbase_fence_cb) + return -ENOMEM; + + fence_get(fence); + + kbase_fence_cb->fence = fence; + kbase_fence_cb->katom = katom; + INIT_LIST_HEAD(&kbase_fence_cb->node); + + err = fence_add_callback(fence, &kbase_fence_cb->fence_cb, callback); + if (err == -ENOENT) { + /* Fence signaled, clear the error and return */ + err = 0; + kbase_fence_cb->fence = NULL; + fence_put(fence); + kfree(kbase_fence_cb); + } else if (err) { + /* Do nothing, just return the error */ + fence_put(fence); + kfree(kbase_fence_cb); + } else { + atomic_inc(&katom->dma_fence.dep_count); + /* Add callback to katom's list of callbacks */ + list_add(&katom->dma_fence.callbacks, &kbase_fence_cb->node); + } + + return err; +} + +static void +kbase_dma_fence_cb(struct fence *fence, struct fence_cb *cb) +{ + struct kbase_dma_fence_cb *kcb = container_of(cb, + struct kbase_dma_fence_cb, + fence_cb); + struct kbase_jd_atom *katom = kcb->katom; + struct kbase_context *kctx = katom->kctx; + + /* If the atom is zapped dep_count will be forced to a negative number + * preventing this callback from ever scheduling work. Which in turn + * would reschedule the atom. + */ + if (atomic_dec_and_test(&katom->dma_fence.dep_count)) { + bool ret; + + INIT_WORK(&katom->work, kbase_dma_fence_work); + ret = queue_work(kctx->dma_fence.wq, &katom->work); + /* Warn if work was already queued, that should not happen. */ + WARN_ON(!ret); + } +} + +static int +kbase_dma_fence_add_reservation_callback(struct kbase_jd_atom *katom, + struct reservation_object *resv, + bool exclusive) +{ + struct fence *excl_fence = NULL; + struct fence **shared_fences = NULL; + unsigned int shared_count = 0; + int err, i; + + err = reservation_object_get_fences_rcu(resv, + &excl_fence, + &shared_count, + &shared_fences); + if (err) + return err; + + if (excl_fence) { + err = kbase_dma_fence_add_callback(katom, + excl_fence, + kbase_dma_fence_cb); + if (err) + goto error; + } + + if (exclusive) { + for (i = 0; i < shared_count; i++) { + err = kbase_dma_fence_add_callback(katom, + shared_fences[i], + kbase_dma_fence_cb); + if (err) + goto error; + } + } + kfree(shared_fences); + + return err; + +error: + /* Cancel and clean up all callbacks that was set up before the error. + */ + kbase_dma_fence_free_callbacks(katom); + kfree(shared_fences); + + return err; +} + +void kbase_dma_fence_add_reservation(struct reservation_object *resv, + struct kbase_dma_fence_resv_info *info, + bool exclusive) +{ + unsigned int i; + + for (i = 0; i < info->dma_fence_resv_count; i++) { + /* Duplicate resource, ignore */ + if (info->resv_objs[i] == resv) + return; + } + + info->resv_objs[info->dma_fence_resv_count] = resv; + if (exclusive) + set_bit(info->dma_fence_resv_count, + info->dma_fence_excl_bitmap); + (info->dma_fence_resv_count)++; +} + +int kbase_dma_fence_wait(struct kbase_jd_atom *katom, + struct kbase_dma_fence_resv_info *info) +{ + int err, i; + struct fence *fence; + struct ww_acquire_ctx ww_ctx; + + lockdep_assert_held(&katom->kctx->jctx.lock); + + atomic_set(&katom->dma_fence.dep_count, 1); + fence = kbase_dma_fence_new(katom->dma_fence.context, + atomic_inc_return(&katom->dma_fence.seqno)); + if (!fence) { + err = -ENOMEM; + dev_err(katom->kctx->kbdev->dev, + "Error %d creating fence.\n", err); + return err; + } + + katom->dma_fence.fence = fence; + + err = kbase_dma_fence_lock_reservations(info, &ww_ctx); + if (err) { + dev_err(katom->kctx->kbdev->dev, + "Error %d locking reservations.\n", err); + return err; + } + + for (i = 0; i < info->dma_fence_resv_count; i++) { + struct reservation_object *obj = info->resv_objs[i]; + + if (!test_bit(i, info->dma_fence_excl_bitmap)) { + err = reservation_object_reserve_shared(obj); + if (err) { + dev_err(katom->kctx->kbdev->dev, + "Error %d reserving space for shared fence.\n", err); + goto end; + } + + err = kbase_dma_fence_add_reservation_callback(katom, obj, false); + if (err) { + dev_err(katom->kctx->kbdev->dev, + "Error %d adding reservation to callback.\n", err); + goto end; + } + + reservation_object_add_shared_fence(obj, katom->dma_fence.fence); + } else { + err = kbase_dma_fence_add_reservation_callback(katom, obj, true); + if (err) { + dev_err(katom->kctx->kbdev->dev, + "Error %d adding reservation to callback.\n", err); + goto end; + } + + reservation_object_add_excl_fence(obj, katom->dma_fence.fence); + } + } + +end: + kbase_dma_fence_unlock_reservations(info, &ww_ctx); + + if (!err) { + /* Test if the callbacks are already triggered */ + if (atomic_dec_and_test(&katom->dma_fence.dep_count)) { + atomic_set(&katom->dma_fence.dep_count, -1); + kbase_dma_fence_free_callbacks(katom); + } else { + /* Add katom to the list of dma-buf fence waiting atoms + * only if it is still waiting. + */ + kbase_dma_fence_waiters_add(katom); + } + } + + return err; +} + +void kbase_dma_fence_cancel_all_atoms(struct kbase_context *kctx) +{ + struct kbase_jd_atom *katom, *katom_tmp; + + list_for_each_entry_safe(katom, katom_tmp, + &kctx->dma_fence.waiting_resource, queue) { + kbase_dma_fence_waiters_remove(katom); + kbase_dma_fence_cancel_atom(katom); + } +} + +void kbase_dma_fence_cancel_callbacks(struct kbase_jd_atom *katom) +{ + /* Cancel callbacks and clean up. */ + kbase_dma_fence_free_callbacks(katom); +} + +void kbase_dma_fence_signal(struct kbase_jd_atom *katom) +{ + if (!katom->dma_fence.fence) + return; + + KBASE_DEBUG_ASSERT(atomic_read(&katom->dma_fence.dep_count) == -1); + + /* Signal the atom's fence. */ + fence_signal(katom->dma_fence.fence); + fence_put(katom->dma_fence.fence); + katom->dma_fence.fence = NULL; + + kbase_dma_fence_free_callbacks(katom); +} + +void kbase_dma_fence_term(struct kbase_context *kctx) +{ + destroy_workqueue(kctx->dma_fence.wq); + kctx->dma_fence.wq = NULL; +} + +int kbase_dma_fence_init(struct kbase_context *kctx) +{ + INIT_LIST_HEAD(&kctx->dma_fence.waiting_resource); + + kctx->dma_fence.wq = alloc_workqueue("mali-fence-%d", + WQ_UNBOUND, 1, kctx->pid); + if (!kctx->dma_fence.wq) + return -ENOMEM; + + return 0; +} |