[PATCH v2 2/5] dmaengine: vdma: Add support for mulit-channel dma mode
Kedareswara rao Appana
appana.durga.rao at xilinx.com
Thu Jun 23 22:21:23 PDT 2016
This patch adds support for AXI DMA multi-channel dma mode
Multichannel mode enables DMA to connect to multiple masters
and slaves on the streaming side.
In Multichannel mode AXI DMA supports 2D transfers.
Signed-off-by: Kedareswara rao Appana <appanad at xilinx.com>
---
Changes for v2:
---> Removed mcdma_config as suggested by vinod
drivers/dma/xilinx/xilinx_vdma.c | 213 +++++++++++++++++++++++++++++++++----
1 files changed, 190 insertions(+), 23 deletions(-)
diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c
index 40f754b..0768d9f 100644
--- a/drivers/dma/xilinx/xilinx_vdma.c
+++ b/drivers/dma/xilinx/xilinx_vdma.c
@@ -114,7 +114,7 @@
#define XILINX_VDMA_REG_START_ADDRESS_64(n) (0x000c + 8 * (n))
/* HW specific definitions */
-#define XILINX_DMA_MAX_CHANS_PER_DEVICE 0x2
+#define XILINX_DMA_MAX_CHANS_PER_DEVICE 0x20
#define XILINX_DMA_DMAXR_ALL_IRQ_MASK \
(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
@@ -165,6 +165,18 @@
#define XILINX_DMA_COALESCE_MAX 255
#define XILINX_DMA_NUM_APP_WORDS 5
+/* Multi-Channel DMA Descriptor offsets*/
+#define XILINX_DMA_MCRX_CDESC(x) (0x40 + (x-1) * 0x20)
+#define XILINX_DMA_MCRX_TDESC(x) (0x48 + (x-1) * 0x20)
+
+/* Multi-Channel DMA Masks/Shifts */
+#define XILINX_DMA_BD_HSIZE_MASK GENMASK(15, 0)
+#define XILINX_DMA_BD_STRIDE_MASK GENMASK(15, 0)
+#define XILINX_DMA_BD_VSIZE_MASK GENMASK(31, 19)
+#define XILINX_DMA_BD_TDEST_MASK GENMASK(4, 0)
+#define XILINX_DMA_BD_STRIDE_SHIFT 0
+#define XILINX_DMA_BD_VSIZE_SHIFT 19
+
/* AXI CDMA Specific Registers/Offsets */
#define XILINX_CDMA_REG_SRCADDR 0x18
#define XILINX_CDMA_REG_DSTADDR 0x20
@@ -210,8 +222,8 @@ struct xilinx_axidma_desc_hw {
u32 next_desc_msb;
u32 buf_addr;
u32 buf_addr_msb;
- u32 pad1;
- u32 pad2;
+ u32 mcdma_control;
+ u32 vsize_stride;
u32 control;
u32 status;
u32 app[XILINX_DMA_NUM_APP_WORDS];
@@ -349,6 +361,7 @@ struct xilinx_dma_chan {
struct xilinx_axidma_tx_segment *seg_v;
struct xilinx_axidma_tx_segment *cyclic_seg_v;
void (*start_transfer)(struct xilinx_dma_chan *chan);
+ u16 tdest;
};
struct xilinx_dma_config {
@@ -365,6 +378,7 @@ struct xilinx_dma_config {
* @common: DMA device structure
* @chan: Driver specific DMA channel
* @has_sg: Specifies whether Scatter-Gather is present or not
+ * @mcdma: Specifies whether Multi-Channel is present or not
* @flush_on_fsync: Flush on frame sync
* @ext_addr: Indicates 64 bit addressing is supported by dma device
* @pdev: Platform device structure pointer
@@ -374,6 +388,8 @@ struct xilinx_dma_config {
* @txs_clk: DMA mm2s stream clock
* @rx_clk: DMA s2mm clock
* @rxs_clk: DMA s2mm stream clock
+ * @nr_channels: Number of channels DMA device supports
+ * @chan_id: DMA channel identifier
*/
struct xilinx_dma_device {
void __iomem *regs;
@@ -381,6 +397,7 @@ struct xilinx_dma_device {
struct dma_device common;
struct xilinx_dma_chan *chan[XILINX_DMA_MAX_CHANS_PER_DEVICE];
bool has_sg;
+ bool mcdma;
u32 flush_on_fsync;
bool ext_addr;
struct platform_device *pdev;
@@ -390,6 +407,8 @@ struct xilinx_dma_device {
struct clk *txs_clk;
struct clk *rx_clk;
struct clk *rxs_clk;
+ u32 nr_channels;
+ u32 chan_id;
};
/* Macros */
@@ -1196,18 +1215,20 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
tail_segment = list_last_entry(&tail_desc->segments,
struct xilinx_axidma_tx_segment, node);
- old_head = list_first_entry(&head_desc->segments,
- struct xilinx_axidma_tx_segment, node);
- new_head = chan->seg_v;
- /* Copy Buffer Descriptor fields. */
- new_head->hw = old_head->hw;
+ if (chan->has_sg && !chan->xdev->mcdma) {
+ old_head = list_first_entry(&head_desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+ new_head = chan->seg_v;
+ /* Copy Buffer Descriptor fields. */
+ new_head->hw = old_head->hw;
- /* Swap and save new reserve */
- list_replace_init(&old_head->node, &new_head->node);
- chan->seg_v = old_head;
+ /* Swap and save new reserve */
+ list_replace_init(&old_head->node, &new_head->node);
+ chan->seg_v = old_head;
- tail_segment->hw.next_desc = chan->seg_v->phys;
- head_desc->async_tx.phys = new_head->phys;
+ tail_segment->hw.next_desc = chan->seg_v->phys;
+ head_desc->async_tx.phys = new_head->phys;
+ }
reg = dma_ctrl_read(chan, XILINX_DMA_REG_DMACR);
@@ -1218,23 +1239,53 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan)
dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg);
}
- if (chan->has_sg)
+ if (chan->has_sg && !chan->xdev->mcdma)
xilinx_write(chan, XILINX_DMA_REG_CURDESC,
head_desc->async_tx.phys);
+ if (chan->has_sg && chan->xdev->mcdma) {
+ if (chan->direction == DMA_MEM_TO_DEV) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_CURDESC,
+ head_desc->async_tx.phys);
+ } else {
+ if (!chan->tdest) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_CURDESC,
+ head_desc->async_tx.phys);
+ } else {
+ dma_ctrl_write(chan,
+ XILINX_DMA_MCRX_CDESC(chan->tdest),
+ head_desc->async_tx.phys);
+ }
+ }
+ }
+
xilinx_dma_start(chan);
if (chan->err)
return;
/* Start the transfer */
- if (chan->has_sg) {
+ if (chan->has_sg && !chan->xdev->mcdma) {
if (chan->cyclic)
xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
chan->cyclic_seg_v->phys);
else
xilinx_write(chan, XILINX_DMA_REG_TAILDESC,
tail_segment->phys);
+ } else if (chan->has_sg && chan->xdev->mcdma) {
+ if (chan->direction == DMA_MEM_TO_DEV) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_TAILDESC,
+ tail_segment->phys);
+ } else {
+ if (!chan->tdest) {
+ dma_ctrl_write(chan, XILINX_DMA_REG_TAILDESC,
+ tail_segment->phys);
+ } else {
+ dma_ctrl_write(chan,
+ XILINX_DMA_MCRX_TDESC(chan->tdest),
+ tail_segment->phys);
+ }
+ }
} else {
struct xilinx_axidma_tx_segment *segment;
struct xilinx_axidma_desc_hw *hw;
@@ -1862,6 +1913,90 @@ error:
}
/**
+ * xilinx_dma_prep_interleaved - prepare a descriptor for a
+ * DMA_SLAVE transaction
+ * @dchan: DMA channel
+ * @xt: Interleaved template pointer
+ * @flags: transfer ack flags
+ *
+ * Return: Async transaction descriptor on success and NULL on failure
+ */
+static struct dma_async_tx_descriptor *
+xilinx_dma_prep_interleaved(struct dma_chan *dchan,
+ struct dma_interleaved_template *xt,
+ unsigned long flags)
+{
+ struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
+ struct xilinx_dma_tx_descriptor *desc;
+ struct xilinx_axidma_tx_segment *segment;
+ struct xilinx_axidma_desc_hw *hw;
+
+ if (!is_slave_direction(xt->dir))
+ return NULL;
+
+ if (!xt->numf || !xt->sgl[0].size)
+ return NULL;
+
+ if (xt->frame_size != 1)
+ return NULL;
+
+ /* Allocate a transaction descriptor. */
+ desc = xilinx_dma_alloc_tx_descriptor(chan);
+ if (!desc)
+ return NULL;
+
+ chan->direction = xt->dir;
+ dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
+ desc->async_tx.tx_submit = xilinx_dma_tx_submit;
+
+ /* Get a free segment */
+ segment = xilinx_axidma_alloc_tx_segment(chan);
+ if (!segment)
+ goto error;
+
+ hw = &segment->hw;
+
+ /* Fill in the descriptor */
+ if (xt->dir != DMA_MEM_TO_DEV)
+ hw->buf_addr = xt->dst_start;
+ else
+ hw->buf_addr = xt->src_start;
+
+ hw->mcdma_control = chan->tdest & XILINX_DMA_BD_TDEST_MASK;
+ hw->vsize_stride = (xt->numf << XILINX_DMA_BD_VSIZE_SHIFT) &
+ XILINX_DMA_BD_VSIZE_MASK;
+ hw->vsize_stride |= (xt->sgl[0].icg + xt->sgl[0].size) &
+ XILINX_DMA_BD_STRIDE_MASK;
+ hw->control = xt->sgl[0].size & XILINX_DMA_BD_HSIZE_MASK;
+
+ /*
+ * Insert the segment into the descriptor segments
+ * list.
+ */
+ list_add_tail(&segment->node, &desc->segments);
+
+
+ segment = list_first_entry(&desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+ desc->async_tx.phys = segment->phys;
+
+ /* For the last DMA_MEM_TO_DEV transfer, set EOP */
+ if (xt->dir == DMA_MEM_TO_DEV) {
+ segment->hw.control |= XILINX_DMA_BD_SOP;
+ segment = list_last_entry(&desc->segments,
+ struct xilinx_axidma_tx_segment,
+ node);
+ segment->hw.control |= XILINX_DMA_BD_EOP;
+ }
+
+ return &desc->async_tx;
+
+error:
+ xilinx_dma_free_tx_descriptor(chan, desc);
+ return NULL;
+}
+
+/**
* xilinx_dma_terminate_all - Halt the channel and free descriptors
* @chan: Driver specific DMA Channel pointer
*/
@@ -2176,7 +2311,7 @@ static void xdma_disable_allclks(struct xilinx_dma_device *xdev)
* Return: '0' on success and failure value on error
*/
static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
- struct device_node *node)
+ struct device_node *node, int chan_id)
{
struct xilinx_dma_chan *chan;
bool has_dre = false;
@@ -2220,7 +2355,8 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel")) {
chan->direction = DMA_MEM_TO_DEV;
- chan->id = 0;
+ chan->id = chan_id;
+ chan->tdest = chan_id;
chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
@@ -2233,7 +2369,8 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
} else if (of_device_is_compatible(node,
"xlnx,axi-vdma-s2mm-channel")) {
chan->direction = DMA_DEV_TO_MEM;
- chan->id = 1;
+ chan->id = chan_id;
+ chan->tdest = chan_id - xdev->nr_channels;
chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
@@ -2288,6 +2425,32 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
}
/**
+ * xilinx_dma_child_probe - Per child node probe
+ * It get number of dma-channels per child node from
+ * device-tree and initializes all the channels.
+ *
+ * @xdev: Driver specific device structure
+ * @node: Device node
+ *
+ * Return: 0 always.
+ */
+static int xilinx_dma_child_probe(struct xilinx_dma_device *xdev,
+ struct device_node *node) {
+ int ret, i, nr_channels = 1;
+
+ ret = of_property_read_u32(node, "dma-channels", &nr_channels);
+ if ((ret < 0) && xdev->mcdma)
+ dev_warn(xdev->dev, "missing dma-channels property\n");
+
+ for (i = 0; i < nr_channels; i++)
+ xilinx_dma_chan_probe(xdev, node, xdev->chan_id++);
+
+ xdev->nr_channels += nr_channels;
+
+ return 0;
+}
+
+/**
* of_dma_xilinx_xlate - Translation function
* @dma_spec: Pointer to DMA specifier as found in the device tree
* @ofdma: Pointer to DMA controller data
@@ -2300,7 +2463,7 @@ static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec,
struct xilinx_dma_device *xdev = ofdma->of_dma_data;
int chan_id = dma_spec->args[0];
- if (chan_id >= XILINX_DMA_MAX_CHANS_PER_DEVICE || !xdev->chan[chan_id])
+ if (chan_id >= xdev->nr_channels || !xdev->chan[chan_id])
return NULL;
return dma_get_slave_channel(&xdev->chan[chan_id]->common);
@@ -2376,6 +2539,8 @@ 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");
+ if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA)
+ xdev->mcdma = of_property_read_bool(node, "xlnx,mcdma");
if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
err = of_property_read_u32(node, "xlnx,num-fstores",
@@ -2426,6 +2591,8 @@ static int xilinx_dma_probe(struct platform_device *pdev)
xdev->common.device_prep_slave_sg = xilinx_dma_prep_slave_sg;
xdev->common.device_prep_dma_cyclic =
xilinx_dma_prep_dma_cyclic;
+ xdev->common.device_prep_interleaved_dma =
+ xilinx_dma_prep_interleaved;
/* Residue calculation is supported by only AXI DMA */
xdev->common.residue_granularity =
DMA_RESIDUE_GRANULARITY_SEGMENT;
@@ -2441,13 +2608,13 @@ static int xilinx_dma_probe(struct platform_device *pdev)
/* Initialize the channels */
for_each_child_of_node(node, child) {
- err = xilinx_dma_chan_probe(xdev, child);
+ err = xilinx_dma_child_probe(xdev, child);
if (err < 0)
goto disable_clks;
}
if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
- for (i = 0; i < XILINX_DMA_MAX_CHANS_PER_DEVICE; i++)
+ for (i = 0; i < xdev->nr_channels; i++)
if (xdev->chan[i])
xdev->chan[i]->num_frms = num_frames;
}
@@ -2470,7 +2637,7 @@ static int xilinx_dma_probe(struct platform_device *pdev)
disable_clks:
xdma_disable_allclks(xdev);
error:
- for (i = 0; i < XILINX_DMA_MAX_CHANS_PER_DEVICE; i++)
+ for (i = 0; i < xdev->nr_channels; i++)
if (xdev->chan[i])
xilinx_dma_chan_remove(xdev->chan[i]);
@@ -2492,7 +2659,7 @@ static int xilinx_dma_remove(struct platform_device *pdev)
dma_async_device_unregister(&xdev->common);
- for (i = 0; i < XILINX_DMA_MAX_CHANS_PER_DEVICE; i++)
+ for (i = 0; i < xdev->nr_channels; i++)
if (xdev->chan[i])
xilinx_dma_chan_remove(xdev->chan[i]);
--
1.7.1
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