Signed-off-by: Jammy Zhou <Jammy.Zhou at amd.com>
Signed-off-by: Shaoyun Liu <Shaoyun.liu at amd.com>
Reviewed-by: Christian K?nig <christian.koenig at amd.com>
---
drivers/gpu/drm/Makefile | 3 +-
drivers/gpu/drm/drm_queue.c | 208 ++++++++++++++++++++++++++++++++++++++++++++
include/drm/drm_queue.h | 47 ++++++++++
3 files changed, 257 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/drm_queue.c
create mode 100644 include/drm/drm_queue.h
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 20f81fd..173d2b6 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -14,7 +14,8 @@ drm-y := drm_auth.o drm_bufs.o drm_cache.o \
drm_info.o drm_debugfs.o drm_encoder_slave.o \
drm_trace_points.o drm_global.o drm_prime.o \
drm_rect.o drm_vma_manager.o drm_flip_work.o \
- drm_modeset_lock.o drm_atomic.o drm_bridge.o
+ drm_modeset_lock.o drm_atomic.o drm_bridge.o \
+ drm_queue.o
drm-$(CONFIG_COMPAT) += drm_ioc32.o
drm-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_gem_cma_helper.o
diff --git a/drivers/gpu/drm/drm_queue.c b/drivers/gpu/drm/drm_queue.c
new file mode 100644
index 0000000..00cd649
--- /dev/null
+++ b/drivers/gpu/drm/drm_queue.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ *
+ * This file implement a generic circular array queue.
+ * It's lock free for single producer and single consumer.
+ *
+ */
+
+#include <linux/atomic.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <drm/drm_queue.h>
+
+#define QUEUE_IDX(_X_) ((_X_)&(queue->size-1))
+
+/**
+ * drm_queue_create - create the queue
+ *
+ * @size total number of elements for this queue
+ * @element_size the memory size of each element entry
+ *
+ * return pointer to the drm_queue structure if succeed, NULL if failed
+ */
+struct drm_queue * drm_queue_create(uint32_t size, uint32_t element_size)
+{
+ struct drm_queue *queue;
+
+ /* check whether the size is power of 2*/
+ BUG_ON(size & (size - 1));
+
+ queue = kzalloc(sizeof(struct drm_queue), GFP_KERNEL);
+ if (!queue)
+ return NULL;
+
+ queue->size = size;
+ queue->element_size = element_size;
+ atomic_set(&queue->count, 0);
+ mutex_init(&queue->lock);
+ queue->data = kzalloc(size * element_size, GFP_KERNEL);
+ if (!queue->data) {
+ kfree(queue);
+ return NULL;
+ }
+
+ return queue;
+}
+
+EXPORT_SYMBOL(drm_queue_create);
+
+/**
+ * drm_queue_free - free the queue storage
+ *
+ * @queue pointer to the queue need to be destroied
+ *
+ * return 0 if succeed. -1 if failed.
+ */
+int drm_queue_free(struct drm_queue *queue)
+{
+ BUG_ON(queue == NULL);
+
+ kfree(queue->data);
+ kfree(queue);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(drm_queue_free);
+
+/**
+ * drm_queue_get_count - Get active count of elements in the queue
+ *
+ * @queue pointer to the queue.
+ *
+ * return current occuptied count of the queue.
+ *
+ */
+int drm_queue_get_count(struct drm_queue *queue)
+{
+ BUG_ON(queue == NULL);
+ return atomic_read(&queue->count);
+}
+
+EXPORT_SYMBOL(drm_queue_get_count);
+
+/**
+ * drm_queue_push - push one element into the queue
+ *
+ * @queue pointer to the queue
+ * @data pointer to the element.
+ *
+ * return 0 if succeed.
+ * -EINVAL if the queue is not valid
+ * -ENOSPC if the queue is full.
+ *
+ * Only one producer is allowed.
+ */
+int drm_queue_push(struct drm_queue *queue, void *data)
+{
+ uint32_t index;
+
+ if (!(queue && queue->data))
+ return -EINVAL;
+
+ if (atomic_read(&queue->count) >= queue->size)
+ return -ENOSPC;
+
+ index = QUEUE_IDX(queue->w_idx++);
+ memcpy(queue->data + index * queue->element_size,
+ data, queue->element_size);
+ barrier();
+ atomic_inc(&queue->count);
+ return 0;
+}
+
+EXPORT_SYMBOL(drm_queue_push);
+
+int drm_queue_push_safe(struct drm_queue *queue, void *data)
+{
+ int r;
+ mutex_lock(&queue->lock);
+ r = drm_queue_push(queue, data);
+ mutex_unlock(&queue->lock);
+ return r;
+}
+
+EXPORT_SYMBOL(drm_queue_push_safe);
+
+/**
+ * drm_queue_pop - pop one element from the queue
+ *
+ * @queue pointer to the queue.
+ * @data pointer to place the element.
+ *
+ * return queue index if succeed.
+ * -EINVAL if the queue is not valid
+ * -ENOSPC if the queue is empty.
+ *
+ * Only one comsummer is allowed
+ */
+
+int drm_queue_pop(struct drm_queue *queue, void *data)
+{
+ uint32_t index;
+
+ if (!(queue && queue->data))
+ return -EINVAL;
+
+ if (atomic_read(&queue->count) == 0)
+ return -ENOSPC;
+
+ index = QUEUE_IDX(queue->r_idx++);
+ memcpy(data, queue->data + index * queue->element_size,
+ queue->element_size);
+ barrier();
+ atomic_dec(&queue->count);
+ return queue->r_idx;
+}
+
+EXPORT_SYMBOL(drm_queue_pop);
+
+/**
+ * drm_queue_peek - Get next element from the queue without removing it
+ *
+ * @queue pointer to the queue.
+ * @data pointer to place the element.
+ *
+ * return 0 if succeed.
+ * -EINVAL if the queue is not valid
+ * -ENOSPC if the queue is empty.
+ */
+
+int drm_queue_peek(struct drm_queue *queue, void *data)
+{
+ uint32_t index;
+
+ if (!(queue && queue->data))
+ return -EINVAL;
+
+ if (atomic_read(&queue->count) == 0)
+ return -ENOSPC;
+
+ index = QUEUE_IDX(queue->r_idx);
+ memcpy(data, queue->data + index * queue->element_size,
+ queue->element_size);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(drm_queue_peek);
diff --git a/include/drm/drm_queue.h b/include/drm/drm_queue.h
new file mode 100644
index 0000000..b8161b4
--- /dev/null
+++ b/include/drm/drm_queue.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ *
+ * Header file for the generic lock free queue
+ *
+ */
+
+struct drm_queue {
+ /* Need to be power of 2*/
+ uint32_t size;
+ /* Current occupied count */
+ atomic_t count;
+ /* Where a new element will be inserted to*/
+ uint32_t w_idx;
+ /* Where the next element will be extracted from */
+ uint32_t r_idx;
+ struct mutex lock;
+ char *data;
+ uint32_t element_size;
+};
+
+struct drm_queue *drm_queue_create(uint32_t size, uint32_t element_size);
+int drm_queue_free(struct drm_queue *queue);
+int drm_queue_push(struct drm_queue *queue, void *data);
+int drm_queue_push_safe(struct drm_queue *queue, void *data);
+int drm_queue_pop(struct drm_queue *queue, void *data);
+int drm_queue_peek(struct drm_queue *queue, void *data);
+int drm_queue_get_count(struct drm_queue *queue);
--
1.9.1
