dmaengine: mv_xor: Add support for scatter-gather DMA mode

This patch adds memory to memory scatter-gather support to the Marvell
mv_or DMA driver.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Marcin Wojtas <mw@semihalf.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Stefan Roese 2016-10-26 10:10:25 +02:00 committed by Vinod Koul
parent e9bb8a9df3
commit c5db858bdf
2 changed files with 180 additions and 4 deletions

View File

@ -68,6 +68,36 @@ static void mv_desc_init(struct mv_xor_desc_slot *desc,
hw_desc->byte_count = byte_count;
}
/* Populate the descriptor */
static void mv_xor_config_sg_ll_desc(struct mv_xor_desc_slot *desc,
dma_addr_t dma_src, dma_addr_t dma_dst,
u32 len, struct mv_xor_desc_slot *prev)
{
struct mv_xor_desc *hw_desc = desc->hw_desc;
hw_desc->status = XOR_DESC_DMA_OWNED;
hw_desc->phy_next_desc = 0;
/* Configure for XOR with only one src address -> MEMCPY */
hw_desc->desc_command = XOR_DESC_OPERATION_XOR | (0x1 << 0);
hw_desc->phy_dest_addr = dma_dst;
hw_desc->phy_src_addr[0] = dma_src;
hw_desc->byte_count = len;
if (prev) {
struct mv_xor_desc *hw_prev = prev->hw_desc;
hw_prev->phy_next_desc = desc->async_tx.phys;
}
}
static void mv_xor_desc_config_eod(struct mv_xor_desc_slot *desc)
{
struct mv_xor_desc *hw_desc = desc->hw_desc;
/* Enable end-of-descriptor interrupt */
hw_desc->desc_command |= XOR_DESC_EOD_INT_EN;
}
static void mv_desc_set_mode(struct mv_xor_desc_slot *desc)
{
struct mv_xor_desc *hw_desc = desc->hw_desc;
@ -228,8 +258,13 @@ mv_chan_clean_completed_slots(struct mv_xor_chan *mv_chan)
list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots,
node) {
if (async_tx_test_ack(&iter->async_tx))
if (async_tx_test_ack(&iter->async_tx)) {
list_move_tail(&iter->node, &mv_chan->free_slots);
if (!list_empty(&iter->sg_tx_list)) {
list_splice_tail_init(&iter->sg_tx_list,
&mv_chan->free_slots);
}
}
}
return 0;
}
@ -244,11 +279,20 @@ mv_desc_clean_slot(struct mv_xor_desc_slot *desc,
/* the client is allowed to attach dependent operations
* until 'ack' is set
*/
if (!async_tx_test_ack(&desc->async_tx))
if (!async_tx_test_ack(&desc->async_tx)) {
/* move this slot to the completed_slots */
list_move_tail(&desc->node, &mv_chan->completed_slots);
else
if (!list_empty(&desc->sg_tx_list)) {
list_splice_tail_init(&desc->sg_tx_list,
&mv_chan->completed_slots);
}
} else {
list_move_tail(&desc->node, &mv_chan->free_slots);
if (!list_empty(&desc->sg_tx_list)) {
list_splice_tail_init(&desc->sg_tx_list,
&mv_chan->free_slots);
}
}
return 0;
}
@ -450,6 +494,7 @@ static int mv_xor_alloc_chan_resources(struct dma_chan *chan)
dma_async_tx_descriptor_init(&slot->async_tx, chan);
slot->async_tx.tx_submit = mv_xor_tx_submit;
INIT_LIST_HEAD(&slot->node);
INIT_LIST_HEAD(&slot->sg_tx_list);
dma_desc = mv_chan->dma_desc_pool;
slot->async_tx.phys = dma_desc + idx * MV_XOR_SLOT_SIZE;
slot->idx = idx++;
@ -617,6 +662,132 @@ mv_xor_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags);
}
/**
* mv_xor_prep_dma_sg - prepare descriptors for a memory sg transaction
* @chan: DMA channel
* @dst_sg: Destination scatter list
* @dst_sg_len: Number of entries in destination scatter list
* @src_sg: Source scatter list
* @src_sg_len: Number of entries in source scatter list
* @flags: transfer ack flags
*
* Return: Async transaction descriptor on success and NULL on failure
*/
static struct dma_async_tx_descriptor *
mv_xor_prep_dma_sg(struct dma_chan *chan, struct scatterlist *dst_sg,
unsigned int dst_sg_len, struct scatterlist *src_sg,
unsigned int src_sg_len, unsigned long flags)
{
struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
struct mv_xor_desc_slot *new;
struct mv_xor_desc_slot *first = NULL;
struct mv_xor_desc_slot *prev = NULL;
size_t len, dst_avail, src_avail;
dma_addr_t dma_dst, dma_src;
int desc_cnt = 0;
int ret;
dev_dbg(mv_chan_to_devp(mv_chan),
"%s dst_sg_len: %d src_sg_len: %d flags: %ld\n",
__func__, dst_sg_len, src_sg_len, flags);
dst_avail = sg_dma_len(dst_sg);
src_avail = sg_dma_len(src_sg);
/* Run until we are out of scatterlist entries */
while (true) {
/* Allocate and populate the descriptor */
desc_cnt++;
new = mv_chan_alloc_slot(mv_chan);
if (!new) {
dev_err(mv_chan_to_devp(mv_chan),
"Out of descriptors (desc_cnt=%d)!\n",
desc_cnt);
goto err;
}
len = min_t(size_t, src_avail, dst_avail);
len = min_t(size_t, len, MV_XOR_MAX_BYTE_COUNT);
if (len == 0)
goto fetch;
if (len < MV_XOR_MIN_BYTE_COUNT) {
dev_err(mv_chan_to_devp(mv_chan),
"Transfer size of %zu too small!\n", len);
goto err;
}
dma_dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) -
dst_avail;
dma_src = sg_dma_address(src_sg) + sg_dma_len(src_sg) -
src_avail;
/* Check if a new window needs to get added for 'dst' */
ret = mv_xor_add_io_win(mv_chan, dma_dst);
if (ret)
goto err;
/* Check if a new window needs to get added for 'src' */
ret = mv_xor_add_io_win(mv_chan, dma_src);
if (ret)
goto err;
/* Populate the descriptor */
mv_xor_config_sg_ll_desc(new, dma_src, dma_dst, len, prev);
prev = new;
dst_avail -= len;
src_avail -= len;
if (!first)
first = new;
else
list_move_tail(&new->node, &first->sg_tx_list);
fetch:
/* Fetch the next dst scatterlist entry */
if (dst_avail == 0) {
if (dst_sg_len == 0)
break;
/* Fetch the next entry: if there are no more: done */
dst_sg = sg_next(dst_sg);
if (dst_sg == NULL)
break;
dst_sg_len--;
dst_avail = sg_dma_len(dst_sg);
}
/* Fetch the next src scatterlist entry */
if (src_avail == 0) {
if (src_sg_len == 0)
break;
/* Fetch the next entry: if there are no more: done */
src_sg = sg_next(src_sg);
if (src_sg == NULL)
break;
src_sg_len--;
src_avail = sg_dma_len(src_sg);
}
}
/* Set the EOD flag in the last descriptor */
mv_xor_desc_config_eod(new);
first->async_tx.flags = flags;
return &first->async_tx;
err:
/* Cleanup: Move all descriptors back into the free list */
spin_lock_bh(&mv_chan->lock);
mv_desc_clean_slot(first, mv_chan);
spin_unlock_bh(&mv_chan->lock);
return NULL;
}
static void mv_xor_free_chan_resources(struct dma_chan *chan)
{
struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
@ -1083,6 +1254,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
dma_dev->device_prep_dma_interrupt = mv_xor_prep_dma_interrupt;
if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy;
if (dma_has_cap(DMA_SG, dma_dev->cap_mask))
dma_dev->device_prep_dma_sg = mv_xor_prep_dma_sg;
if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
dma_dev->max_xor = 8;
dma_dev->device_prep_dma_xor = mv_xor_prep_dma_xor;
@ -1132,10 +1305,11 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
goto err_free_irq;
}
dev_info(&pdev->dev, "Marvell XOR (%s): ( %s%s%s)\n",
dev_info(&pdev->dev, "Marvell XOR (%s): ( %s%s%s%s)\n",
mv_chan->op_in_desc ? "Descriptor Mode" : "Registers Mode",
dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "sg " : "",
dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : "");
dma_async_device_register(dma_dev);
@ -1378,6 +1552,7 @@ static int mv_xor_probe(struct platform_device *pdev)
dma_cap_zero(cap_mask);
dma_cap_set(DMA_MEMCPY, cap_mask);
dma_cap_set(DMA_SG, cap_mask);
dma_cap_set(DMA_XOR, cap_mask);
dma_cap_set(DMA_INTERRUPT, cap_mask);

View File

@ -148,6 +148,7 @@ struct mv_xor_chan {
*/
struct mv_xor_desc_slot {
struct list_head node;
struct list_head sg_tx_list;
enum dma_transaction_type type;
void *hw_desc;
u16 idx;