[PATCH v2 1/2] dmaengine: Add support for MEMCPY for imx-dma.
Javier Martin
javier.martin at vista-silicon.com
Tue Feb 28 11:08:17 EST 2012
MEMCPY transfers allow DMA copies from memory to
memory. This patch has been tested with dmatest
device driver.
Signed-off-by: Javier Martin <javier.martin at vista-silicon.com>
---
drivers/dma/imx-dma.c | 36 +++++++++++++++++++++++++++++++++++-
1 files changed, 35 insertions(+), 1 deletions(-)
diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c
index 3296a73..9aa6e85 100644
--- a/drivers/dma/imx-dma.c
+++ b/drivers/dma/imx-dma.c
@@ -196,7 +196,8 @@ static int imxdma_alloc_chan_resources(struct dma_chan *chan)
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imx_dma_data *data = chan->private;
- imxdmac->dma_request = data->dma_request;
+ if (data != NULL)
+ imxdmac->dma_request = data->dma_request;
dma_async_tx_descriptor_init(&imxdmac->desc, chan);
imxdmac->desc.tx_submit = imxdma_tx_submit;
@@ -328,6 +329,36 @@ static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
return &imxdmac->desc;
}
+static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
+ struct dma_chan *chan, dma_addr_t dest,
+ dma_addr_t src, size_t len, unsigned long flags)
+{
+ struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
+ struct imxdma_engine *imxdma = imxdmac->imxdma;
+ int ret;
+
+ dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
+ __func__, imxdmac->channel, src, dest, len);
+
+ if (imxdmac->status == DMA_IN_PROGRESS)
+ return NULL;
+ imxdmac->status = DMA_IN_PROGRESS;
+
+ ret = imx_dma_config_channel(imxdmac->imxdma_channel,
+ IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
+ IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
+ 0, 0);
+ if (ret)
+ return NULL;
+
+ ret = imx_dma_setup_single(imxdmac->imxdma_channel, src, len,
+ dest, DMA_MODE_WRITE);
+ if (ret)
+ return NULL;
+
+ return &imxdmac->desc;
+}
+
static void imxdma_issue_pending(struct dma_chan *chan)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
@@ -349,6 +380,7 @@ static int __init imxdma_probe(struct platform_device *pdev)
dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
+ dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
/* Initialize channel parameters */
for (i = 0; i < MAX_DMA_CHANNELS; i++) {
@@ -382,11 +414,13 @@ static int __init imxdma_probe(struct platform_device *pdev)
imxdma->dma_device.device_tx_status = imxdma_tx_status;
imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
+ imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
imxdma->dma_device.device_control = imxdma_control;
imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
platform_set_drvdata(pdev, imxdma);
+ imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
--
1.7.0.4
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