[PATCH 1/2] dmaengine: fsl-edma: add dma memcpy support
Jingchang Lu
jingchang.lu at freescale.com
Tue Dec 30 00:41:46 PST 2014
This adds the memory copy capability support, the memcpy
functionality needs to configure the DMAMUX of the channel
with the always on slave id.
Signed-off-by: Jingchang Lu <jingchang.lu at freescale.com>
---
drivers/dma/fsl-edma.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 61 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
index 09e2842..e0bd517 100644
--- a/drivers/dma/fsl-edma.c
+++ b/drivers/dma/fsl-edma.c
@@ -110,6 +110,8 @@
#define EDMAMUX_CHCFG_ENBL 0x80
#define EDMAMUX_CHCFG_SOURCE(n) ((n) & 0x3F)
+#define SLAVE_ID_ALWAYSON 63 /* the always on slave id */
+
#define DMAMUX_NR 2
#define FSL_EDMA_BUSWIDTHS BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
@@ -147,6 +149,7 @@ struct fsl_edma_slave_config {
struct fsl_edma_chan {
struct virt_dma_chan vchan;
enum dma_status status;
+ u32 slave_id;
struct fsl_edma_engine *edma;
struct fsl_edma_desc *edesc;
struct fsl_edma_slave_config fsc;
@@ -637,6 +640,45 @@ static struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg(
return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
}
+static struct dma_async_tx_descriptor *
+fsl_edma_prep_memcpy(struct dma_chan *chan, dma_addr_t dst,
+ dma_addr_t src, size_t len, unsigned long tx_flags)
+{
+ struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
+ struct fsl_edma_desc *fsl_desc;
+ u16 soff, doff, attr;
+
+ /*
+ * use 4-bytes data transfer size if all is 4-bytes aligned,
+ * else 2-bytes data transfer size of all is 2-bytes aligned,
+ * otherwise 1-byte tranfer size.
+ */
+ if (src & 0x1 || dst & 0x1 || len & 0x1) {
+ attr = EDMA_TCD_ATTR_SSIZE_8BIT | EDMA_TCD_ATTR_DSIZE_8BIT;
+ soff = 0x1;
+ doff = 0x1;
+ } else if (src & 0x2 || dst & 0x2 || len & 0x2) {
+ attr = EDMA_TCD_ATTR_SSIZE_16BIT | EDMA_TCD_ATTR_DSIZE_16BIT;
+ soff = 0x2;
+ doff = 0x2;
+ } else {
+ attr = EDMA_TCD_ATTR_SSIZE_32BIT | EDMA_TCD_ATTR_DSIZE_32BIT;
+ soff = 0x4;
+ doff = 0x4;
+ }
+
+ fsl_desc = fsl_edma_alloc_desc(fsl_chan, 1);
+ if (!fsl_desc)
+ return NULL;
+ fsl_desc->iscyclic = false;
+
+ fsl_edma_fill_tcd(fsl_desc->tcd[0].vtcd, src, dst, attr, soff, len,
+ 0, 1, 1, doff, 0, true, true, false);
+
+ return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, tx_flags);
+
+}
+
static void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan)
{
struct virt_dma_desc *vdesc;
@@ -735,6 +777,7 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
{
struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
struct dma_chan *chan, *_chan;
+ struct fsl_edma_chan *fsl_chan;
unsigned long chans_per_mux = fsl_edma->n_chans / DMAMUX_NR;
if (dma_spec->args_count != 2)
@@ -748,8 +791,10 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
chan = dma_get_slave_channel(chan);
if (chan) {
chan->device->privatecnt++;
- fsl_edma_chan_mux(to_fsl_edma_chan(chan),
- dma_spec->args[1], true);
+ fsl_chan = to_fsl_edma_chan(chan);
+ fsl_chan->slave_id = dma_spec->args[1];
+ fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id,
+ true);
mutex_unlock(&fsl_edma->fsl_edma_mutex);
return chan;
}
@@ -763,6 +808,17 @@ static int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
{
struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
+ /*
+ * If the slave id of the channel DMAMUX is not set yet,
+ * this could happy when the channel is requested by the
+ * dma_request_channel() for memory copy purpose instead
+ * of by dts binding, then configure the DMAMUX with the
+ * always on slave id.
+ */
+ if (fsl_chan->slave_id == 0) {
+ fsl_chan->slave_id = SLAVE_ID_ALWAYSON;
+ fsl_edma_chan_mux(fsl_chan, fsl_chan->slave_id, true);
+ }
fsl_chan->tcd_pool = dma_pool_create("tcd_pool", chan->device->dev,
sizeof(struct fsl_edma_hw_tcd),
32, 0);
@@ -778,6 +834,7 @@ static void fsl_edma_free_chan_resources(struct dma_chan *chan)
spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
fsl_edma_disable_request(fsl_chan);
fsl_edma_chan_mux(fsl_chan, 0, false);
+ fsl_chan->slave_id = 0;
fsl_chan->edesc = NULL;
vchan_get_all_descriptors(&fsl_chan->vchan, &head);
spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
@@ -903,6 +960,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
+ dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
fsl_edma->dma_dev.dev = &pdev->dev;
fsl_edma->dma_dev.device_alloc_chan_resources
@@ -912,6 +970,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
+ fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
fsl_edma->dma_dev.device_pause = fsl_edma_pause;
fsl_edma->dma_dev.device_resume = fsl_edma_resume;
--
1.8.0
More information about the linux-arm-kernel
mailing list