[PATCH v2 01/10] dmaengine: omap-dma: port_window support correction for both direction

From: Peter Ujfalusi
Date: Wed May 10 2017 - 04:43:05 EST


When the port_window support was verified it was done on setup where only
the MEM_TO_DEV direction was enabled. This got un-noticed and thus only
this direction worked.

Now that I have managed to get a setup to verify both direction it turned
out that the setup was incorrect:
omap_desc members are settings for the slave port while the omap_sg members
apply to the memory side of the sDMA setup.

Fixes: 527a27591312 ("dmaengine: omap-dma: Fix the port_window support")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: dan.j.williams@xxxxxxxxx
Cc: vinod.koul@xxxxxxxxx
---
drivers/dma/omap-dma.c | 39 +++++++++++++++------------------------
1 file changed, 15 insertions(+), 24 deletions(-)

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index eed745a598fa..4fc86d40b50c 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -948,12 +948,6 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
return NULL;
}

- /* When the port_window is used, one frame must cover the window */
- if (port_window) {
- burst = port_window;
- port_window_bytes = port_window * es_bytes[es];
- }
-
/* Now allocate and setup the descriptor. */
d = kzalloc(sizeof(*d) + sglen * sizeof(d->sg[0]), GFP_ATOMIC);
if (!d)
@@ -963,6 +957,21 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
d->dev_addr = dev_addr;
d->es = es;

+ /* When the port_window is used, one frame must cover the window */
+ if (port_window) {
+ burst = port_window;
+ port_window_bytes = port_window * es_bytes[es];
+
+ d->ei = 1;
+ /*
+ * One frame covers the port_window and by configure
+ * the source frame index to be -1 * (port_window - 1)
+ * we instruct the sDMA that after a frame is processed
+ * it should move back to the start of the window.
+ */
+ d->fi = -(port_window_bytes - 1);
+ }
+
d->ccr = c->ccr | CCR_SYNC_FRAME;
if (dir == DMA_DEV_TO_MEM) {
d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
@@ -987,14 +996,6 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
d->ccr |= CCR_SRC_AMODE_POSTINC;
if (port_window) {
d->ccr |= CCR_DST_AMODE_DBLIDX;
- d->ei = 1;
- /*
- * One frame covers the port_window and by configure
- * the source frame index to be -1 * (port_window - 1)
- * we instruct the sDMA that after a frame is processed
- * it should move back to the start of the window.
- */
- d->fi = -(port_window_bytes - 1);

if (port_window_bytes >= 64)
d->csdp |= CSDP_DST_BURST_64;
@@ -1050,16 +1051,6 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
osg->addr = sg_dma_address(sgent);
osg->en = en;
osg->fn = sg_dma_len(sgent) / frame_bytes;
- if (port_window && dir == DMA_DEV_TO_MEM) {
- osg->ei = 1;
- /*
- * One frame covers the port_window and by configure
- * the source frame index to be -1 * (port_window - 1)
- * we instruct the sDMA that after a frame is processed
- * it should move back to the start of the window.
- */
- osg->fi = -(port_window_bytes - 1);
- }

if (d->using_ll) {
osg->t2_desc = dma_pool_alloc(od->desc_pool, GFP_ATOMIC,
--
2.12.2