rt-thread/components/drivers/virtio/virtio.c

325 lines
7.4 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2021-11-11 GuEe-GUI the first version
*/
#include <rtthread.h>
#include <cpuport.h>
#include <virtio.h>
rt_inline void _virtio_dev_check(struct virtio_device *dev)
{
RT_ASSERT(dev != RT_NULL);
RT_ASSERT(dev->mmio_config != RT_NULL);
}
void virtio_reset_device(struct virtio_device *dev)
{
_virtio_dev_check(dev);
dev->mmio_config->status = 0;
}
void virtio_status_acknowledge_driver(struct virtio_device *dev)
{
_virtio_dev_check(dev);
dev->mmio_config->status |= VIRTIO_STATUS_ACKNOWLEDGE | VIRTIO_STATUS_DRIVER;
}
void virtio_status_driver_ok(struct virtio_device *dev)
{
_virtio_dev_check(dev);
dev->mmio_config->status |= VIRTIO_STATUS_FEATURES_OK | VIRTIO_STATUS_DRIVER_OK;
}
void virtio_interrupt_ack(struct virtio_device *dev)
{
rt_uint32_t status;
_virtio_dev_check(dev);
status = dev->mmio_config->interrupt_status;
if (status != 0)
{
dev->mmio_config->interrupt_ack = status;
}
}
rt_bool_t virtio_has_feature(struct virtio_device *dev, rt_uint32_t feature_bit)
{
_virtio_dev_check(dev);
return !!(dev->mmio_config->device_features & (1UL << feature_bit));
}
rt_err_t virtio_queues_alloc(struct virtio_device *dev, rt_size_t queues_num)
{
_virtio_dev_check(dev);
dev->queues = rt_malloc(sizeof(struct virtq) * queues_num);
if (dev->queues != RT_NULL)
{
dev->queues_num = queues_num;
return RT_EOK;
}
return -RT_ENOMEM;
}
void virtio_queues_free(struct virtio_device *dev)
{
if (dev->queues != RT_NULL)
{
dev->queues_num = 0;
rt_free(dev->queues);
}
}
rt_err_t virtio_queue_init(struct virtio_device *dev, rt_uint32_t queue_index, rt_size_t ring_size)
{
int i;
void *pages;
rt_size_t pages_total_size;
struct virtq *queue;
_virtio_dev_check(dev);
RT_ASSERT(dev->mmio_config->queue_num_max > 0);
RT_ASSERT(dev->mmio_config->queue_num_max > queue_index);
/* ring_size is power of 2 */
RT_ASSERT(ring_size > 0);
RT_ASSERT(((ring_size - 1) & ring_size) == 0);
queue = &dev->queues[queue_index];
pages_total_size = VIRTIO_PAGE_ALIGN(
VIRTQ_DESC_TOTAL_SIZE(ring_size) + VIRTQ_AVAIL_TOTAL_SIZE(ring_size)) + VIRTQ_USED_TOTAL_SIZE(ring_size);
pages = rt_malloc_align(pages_total_size, VIRTIO_PAGE_SIZE);
if (pages == RT_NULL)
{
return -RT_ENOMEM;
}
queue->free = rt_malloc(sizeof(rt_bool_t) * ring_size);
if (queue->free == RT_NULL)
{
rt_free_align(pages);
return -RT_ENOMEM;
}
rt_memset(pages, 0, pages_total_size);
dev->mmio_config->guest_page_size = VIRTIO_PAGE_SIZE;
dev->mmio_config->queue_sel = queue_index;
dev->mmio_config->queue_num = ring_size;
dev->mmio_config->queue_align = VIRTIO_PAGE_SIZE;
dev->mmio_config->queue_pfn = VIRTIO_VA2PA(pages) >> VIRTIO_PAGE_SHIFT;
queue->num = ring_size;
queue->desc = (struct virtq_desc *)((rt_ubase_t)pages);
queue->avail = (struct virtq_avail *)(((rt_ubase_t)pages) + VIRTQ_DESC_TOTAL_SIZE(ring_size));
queue->used = (struct virtq_used *)VIRTIO_PAGE_ALIGN(
(rt_ubase_t)&queue->avail->ring[ring_size] + VIRTQ_AVAIL_RES_SIZE);
queue->used_idx = 0;
/* All descriptors start out unused */
for (i = 0; i < ring_size; ++i)
{
queue->free[i] = RT_TRUE;
}
queue->free_count = ring_size;
return RT_EOK;
}
void virtio_queue_destroy(struct virtio_device *dev, rt_uint32_t queue_index)
{
struct virtq *queue;
_virtio_dev_check(dev);
RT_ASSERT(dev->mmio_config->queue_num_max > 0);
RT_ASSERT(dev->mmio_config->queue_num_max > queue_index);
queue = &dev->queues[queue_index];
RT_ASSERT(queue->num > 0);
rt_free(queue->free);
rt_free_align((void *)queue->desc);
dev->mmio_config->queue_sel = queue_index;
dev->mmio_config->queue_pfn = RT_NULL;
queue->num = 0;
queue->desc = RT_NULL;
queue->avail = RT_NULL;
queue->used = RT_NULL;
}
void virtio_queue_notify(struct virtio_device *dev, rt_uint32_t queue_index)
{
_virtio_dev_check(dev);
dev->mmio_config->queue_notify = queue_index;
}
void virtio_submit_chain(struct virtio_device *dev, rt_uint32_t queue_index, rt_uint16_t desc_index)
{
rt_size_t ring_size;
struct virtq *queue;
_virtio_dev_check(dev);
queue = &dev->queues[queue_index];
ring_size = queue->num;
/* Tell the device the first index in our chain of descriptors */
queue->avail->ring[queue->avail->idx % ring_size] = desc_index;
rt_hw_dsb();
/* Tell the device another avail ring entry is available */
queue->avail->idx++;
rt_hw_dsb();
}
rt_uint16_t virtio_alloc_desc(struct virtio_device *dev, rt_uint32_t queue_index)
{
int i;
struct virtq *queue;
_virtio_dev_check(dev);
RT_ASSERT(queue_index < dev->queues_num);
queue = &dev->queues[queue_index];
if (queue->free_count > 0)
{
rt_size_t ring_size = queue->num;
for (i = 0; i < ring_size; ++i)
{
if (queue->free[i])
{
queue->free[i] = RT_FALSE;
queue->free_count--;
return (rt_uint16_t)i;
}
}
}
return VIRTQ_INVALID_DESC_ID;
}
void virtio_free_desc(struct virtio_device *dev, rt_uint32_t queue_index, rt_uint16_t desc_index)
{
struct virtq *queue;
_virtio_dev_check(dev);
queue = &dev->queues[queue_index];
RT_ASSERT(queue_index < dev->queues_num);
RT_ASSERT(!queue->free[desc_index]);
queue->desc[desc_index].addr = 0;
queue->desc[desc_index].len = 0;
queue->desc[desc_index].flags = 0;
queue->desc[desc_index].next = 0;
queue->free[desc_index] = RT_TRUE;
queue->free_count++;
}
rt_err_t virtio_alloc_desc_chain(struct virtio_device *dev, rt_uint32_t queue_index, rt_size_t count,
rt_uint16_t *indexs)
{
int i, j;
_virtio_dev_check(dev);
RT_ASSERT(indexs != RT_NULL);
if (dev->queues[queue_index].free_count < count)
{
return -RT_ERROR;
}
for (i = 0; i < count; ++i)
{
indexs[i] = virtio_alloc_desc(dev, queue_index);
if (indexs[i] == VIRTQ_INVALID_DESC_ID)
{
for (j = 0; j < i; ++j)
{
virtio_free_desc(dev, queue_index, indexs[j]);
}
return -RT_ERROR;
}
}
return RT_EOK;
}
void virtio_free_desc_chain(struct virtio_device *dev, rt_uint32_t queue_index, rt_uint16_t desc_index)
{
rt_uint16_t flags, next;
struct virtq_desc *desc;
_virtio_dev_check(dev);
desc = &dev->queues[queue_index].desc[0];
for (;;)
{
flags = desc[desc_index].flags;
next = desc[desc_index].next;
virtio_free_desc(dev, queue_index, desc_index);
if (flags & VIRTQ_DESC_F_NEXT)
{
desc_index = next;
}
else
{
break;
}
}
}
void virtio_fill_desc(struct virtio_device *dev, rt_uint32_t queue_index, rt_uint16_t desc_index,
rt_uint64_t addr, rt_uint32_t len, rt_uint16_t flags, rt_uint16_t next)
{
struct virtq_desc *desc;
_virtio_dev_check(dev);
desc = &dev->queues[queue_index].desc[desc_index];
desc->addr = addr;
desc->len = len;
desc->flags = flags;
desc->next = next;
}