[PATCH v2 2/6] DMA: PL330: Infer transfer direction from transfer request instead of platform data
Thomas Abraham
thomas.abraham at linaro.org
Thu Sep 1 05:04:38 EDT 2011
The transfer direction for a channel can be inferred from the transfer
request and the need for specifying transfer direction in platfrom data
can be eliminated. So the structure definition 'struct dma_pl330_peri'
is no longer required.
The channel's private data is set to point to a channel id specified in
the platform data (instead of an instance of type 'struct dma_pl330_peri').
The filter function is correspondingly modified to match the channel id.
With the 'struct dma_pl330_peri' removed from platform data, the dma
controller transfer capabilities cannot be inferred any more. Hence,
the dma controller capabilities is specified using platform data.
Cc: Jassi Brar <jassisinghbrar at gmail.com>
Cc: Boojin Kim <boojin.kim at samsung.com>
Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
Acked-by: Jassi Brar <jassisinghbrar at gmail.com>
---
drivers/dma/pl330.c | 65 +++++++++++---------------------------------
include/linux/amba/pl330.h | 13 ++-------
2 files changed, 19 insertions(+), 59 deletions(-)
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 7df2516..9732995 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -272,13 +272,13 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err)
bool pl330_filter(struct dma_chan *chan, void *param)
{
- struct dma_pl330_peri *peri;
+ u8 *peri_id;
if (chan->device->dev->driver != &pl330_driver.drv)
return false;
- peri = chan->private;
- return peri->peri_id == (unsigned)param;
+ peri_id = chan->private;
+ return *peri_id == (unsigned)param;
}
EXPORT_SYMBOL(pl330_filter);
@@ -514,7 +514,7 @@ pluck_desc(struct dma_pl330_dmac *pdmac)
static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
{
struct dma_pl330_dmac *pdmac = pch->dmac;
- struct dma_pl330_peri *peri = pch->chan.private;
+ u8 *peri_id = pch->chan.private;
struct dma_pl330_desc *desc;
/* Pluck one desc from the pool of DMAC */
@@ -539,13 +539,7 @@ static struct dma_pl330_desc *pl330_get_desc(struct dma_pl330_chan *pch)
desc->txd.cookie = 0;
async_tx_ack(&desc->txd);
- if (peri) {
- desc->req.rqtype = peri->rqtype;
- desc->req.peri = pch->chan.chan_id;
- } else {
- desc->req.rqtype = MEMTOMEM;
- desc->req.peri = 0;
- }
+ desc->req.peri = peri_id ? pch->chan.chan_id : 0;
dma_async_tx_descriptor_init(&desc->txd, &pch->chan);
@@ -632,12 +626,14 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic(
case DMA_TO_DEVICE:
desc->rqcfg.src_inc = 1;
desc->rqcfg.dst_inc = 0;
+ desc->req.rqtype = MEMTODEV;
src = dma_addr;
dst = pch->fifo_addr;
break;
case DMA_FROM_DEVICE:
desc->rqcfg.src_inc = 0;
desc->rqcfg.dst_inc = 1;
+ desc->req.rqtype = DEVTOMEM;
src = pch->fifo_addr;
dst = dma_addr;
break;
@@ -663,16 +659,12 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
{
struct dma_pl330_desc *desc;
struct dma_pl330_chan *pch = to_pchan(chan);
- struct dma_pl330_peri *peri = chan->private;
struct pl330_info *pi;
int burst;
if (unlikely(!pch || !len))
return NULL;
- if (peri && peri->rqtype != MEMTOMEM)
- return NULL;
-
pi = &pch->dmac->pif;
desc = __pl330_prep_dma_memcpy(pch, dst, src, len);
@@ -681,6 +673,7 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
desc->rqcfg.src_inc = 1;
desc->rqcfg.dst_inc = 1;
+ desc->req.rqtype = MEMTOMEM;
/* Select max possible burst size */
burst = pi->pcfg.data_bus_width / 8;
@@ -709,24 +702,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
{
struct dma_pl330_desc *first, *desc = NULL;
struct dma_pl330_chan *pch = to_pchan(chan);
- struct dma_pl330_peri *peri = chan->private;
struct scatterlist *sg;
unsigned long flags;
int i;
dma_addr_t addr;
- if (unlikely(!pch || !sgl || !sg_len || !peri))
- return NULL;
-
- /* Make sure the direction is consistent */
- if ((direction == DMA_TO_DEVICE &&
- peri->rqtype != MEMTODEV) ||
- (direction == DMA_FROM_DEVICE &&
- peri->rqtype != DEVTOMEM)) {
- dev_err(pch->dmac->pif.dev, "%s:%d Invalid Direction\n",
- __func__, __LINE__);
+ if (unlikely(!pch || !sgl || !sg_len))
return NULL;
- }
addr = pch->fifo_addr;
@@ -767,11 +749,13 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
if (direction == DMA_TO_DEVICE) {
desc->rqcfg.src_inc = 1;
desc->rqcfg.dst_inc = 0;
+ desc->req.rqtype = MEMTODEV;
fill_px(&desc->px,
addr, sg_dma_address(sg), sg_dma_len(sg));
} else {
desc->rqcfg.src_inc = 0;
desc->rqcfg.dst_inc = 1;
+ desc->req.rqtype = DEVTOMEM;
fill_px(&desc->px,
sg_dma_address(sg), addr, sg_dma_len(sg));
}
@@ -878,28 +862,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
for (i = 0; i < num_chan; i++) {
pch = &pdmac->peripherals[i];
- if (pdat) {
- struct dma_pl330_peri *peri = &pdat->peri[i];
-
- switch (peri->rqtype) {
- case MEMTOMEM:
- dma_cap_set(DMA_MEMCPY, pd->cap_mask);
- break;
- case MEMTODEV:
- case DEVTOMEM:
- dma_cap_set(DMA_SLAVE, pd->cap_mask);
- dma_cap_set(DMA_CYCLIC, pd->cap_mask);
- break;
- default:
- dev_err(&adev->dev, "DEVTODEV Not Supported\n");
- continue;
- }
- pch->chan.private = peri;
- } else {
- dma_cap_set(DMA_MEMCPY, pd->cap_mask);
- pch->chan.private = NULL;
- }
-
+ pch->chan.private = pdat ? &pdat->peri_id[i] : NULL;
INIT_LIST_HEAD(&pch->work_list);
spin_lock_init(&pch->lock);
pch->pl330_chid = NULL;
@@ -913,6 +876,10 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
}
pd->dev = &adev->dev;
+ if (pdat)
+ pd->cap_mask = pdat->cap_mask;
+ else
+ dma_cap_set(DMA_MEMCPY, pd->cap_mask);
pd->device_alloc_chan_resources = pl330_alloc_chan_resources;
pd->device_free_chan_resources = pl330_free_chan_resources;
diff --git a/include/linux/amba/pl330.h b/include/linux/amba/pl330.h
index 6db72da..12e023c 100644
--- a/include/linux/amba/pl330.h
+++ b/include/linux/amba/pl330.h
@@ -15,15 +15,6 @@
#include <linux/dmaengine.h>
#include <asm/hardware/pl330.h>
-struct dma_pl330_peri {
- /*
- * Peri_Req i/f of the DMAC that is
- * peripheral could be reached from.
- */
- u8 peri_id; /* specific dma id */
- enum pl330_reqtype rqtype;
-};
-
struct dma_pl330_platdata {
/*
* Number of valid peripherals connected to DMAC.
@@ -34,7 +25,9 @@ struct dma_pl330_platdata {
*/
u8 nr_valid_peri;
/* Array of valid peripherals */
- struct dma_pl330_peri *peri;
+ u8 *peri_id;
+ /* Operational capabilities */
+ dma_cap_mask_t cap_mask;
/* Bytes to allocate for MC buffer */
unsigned mcbuf_sz;
};
--
1.6.6.rc2
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