From: Andrea Merello <andrea.merello@xxxxxxxxx>
[ Upstream commit 616f0f81d857e248a72b5af45ab185196556ae2e ]
This patch removes a bit of duplicated code by introducing a new
function that implements calculations for DMA copy size, and
prepares for changes to the copy size calculation that will
happen in following patches.
Suggested-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Andrea Merello <andrea.merello@xxxxxxxxx>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Stable-dep-of: 596b53ccc36a ("dmaengine: xilinx_dma: call of_node_put() when breaking out of for_each_child_of_node()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/xilinx/xilinx_dma.c | 39 ++++++++++++++++++++++++++-------
1 file changed, 31 insertions(+), 8 deletions(-)
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index 0ba70be4ea85..e4ea94b93400 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -428,6 +428,7 @@ struct xilinx_dma_config {
* @rxs_clk: DMA s2mm stream clock
* @nr_channels: Number of channels DMA device supports
* @chan_id: DMA channel identifier
+ * @max_buffer_len: Max buffer length
*/
struct xilinx_dma_device {
void __iomem *regs;
@@ -447,6 +448,7 @@ struct xilinx_dma_device {
struct clk *rxs_clk;
u32 nr_channels;
u32 chan_id;
+ u32 max_buffer_len;
};
/* Macros */
@@ -969,6 +971,25 @@ static int xilinx_dma_alloc_chan_resources(struct dma_chan *dchan)
return 0;
}
+/**
+ * xilinx_dma_calc_copysize - Calculate the amount of data to copy
+ * @chan: Driver specific DMA channel
+ * @size: Total data that needs to be copied
+ * @done: Amount of data that has been already copied
+ *
+ * Return: Amount of data that has to be copied
+ */
+static int xilinx_dma_calc_copysize(struct xilinx_dma_chan *chan,
+ int size, int done)
+{
+ size_t copy;
+
+ copy = min_t(size_t, size - done,
+ chan->xdev->max_buffer_len);
+
+ return copy;
+}
+
/**
* xilinx_dma_tx_status - Get DMA transaction status
* @dchan: DMA channel
@@ -1002,7 +1023,7 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan,
list_for_each_entry(segment, &desc->segments, node) {
hw = &segment->hw;
residue += (hw->control - hw->status) &
- XILINX_DMA_MAX_TRANS_LEN;
+ chan->xdev->max_buffer_len;
}
}
spin_unlock_irqrestore(&chan->lock, flags);
@@ -1262,7 +1283,7 @@ static void xilinx_cdma_start_transfer(struct xilinx_dma_chan *chan)
/* Start the transfer */
dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
- hw->control & XILINX_DMA_MAX_TRANS_LEN);
+ hw->control & chan->xdev->max_buffer_len);
}
list_splice_tail_init(&chan->pending_list, &chan->active_list);
@@ -1365,7 +1386,7 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
/* Start the transfer */
dma_ctrl_write(chan, XILINX_DMA_REG_BTT,
- hw->control & XILINX_DMA_MAX_TRANS_LEN);
+ hw->control & chan->xdev->max_buffer_len);
}
list_splice_tail_init(&chan->pending_list, &chan->active_list);
@@ -1729,7 +1750,7 @@ xilinx_cdma_prep_memcpy(struct dma_chan *dchan, dma_addr_t dma_dst,
struct xilinx_cdma_tx_segment *segment;
struct xilinx_cdma_desc_hw *hw;
- if (!len || len > XILINX_DMA_MAX_TRANS_LEN)
+ if (!len || len > chan->xdev->max_buffer_len)
return NULL;
desc = xilinx_dma_alloc_tx_descriptor(chan);
@@ -1819,8 +1840,8 @@ static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
* Calculate the maximum number of bytes to transfer,
* making sure it is less than the hw limit
*/
- copy = min_t(size_t, sg_dma_len(sg) - sg_used,
- XILINX_DMA_MAX_TRANS_LEN);
+ copy = xilinx_dma_calc_copysize(chan, sg_dma_len(sg),
+ sg_used);
hw = &segment->hw;
/* Fill in the descriptor */
@@ -1924,8 +1945,8 @@ static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic(
* Calculate the maximum number of bytes to transfer,
* making sure it is less than the hw limit
*/
- copy = min_t(size_t, period_len - sg_used,
- XILINX_DMA_MAX_TRANS_LEN);
+ copy = xilinx_dma_calc_copysize(chan, period_len,
+ sg_used);
hw = &segment->hw;
xilinx_axidma_buf(chan, hw, buf_addr, sg_used,
period_len * i);
@@ -2645,6 +2666,8 @@ static int xilinx_dma_probe(struct platform_device *pdev)
/* Retrieve the DMA engine properties from the device tree */
xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg");
+ xdev->max_buffer_len = XILINX_DMA_MAX_TRANS_LEN;
+
if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
xdev->mcdma = of_property_read_bool(node, "xlnx,mcdma");
--
2.39.0
