[PATCH v4 11/18] dmaengine: dma-jz4780: Add missing residue DTC mask

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Daniel Silsby <dansilsby@xxxxxxxxx>

The 'dtc' word in jz DMA descriptors contains two fields: The
lowest 24 bits are the transfer count, and upper 8 bits are the DOA
offset to next descriptor. The upper 8 bits are now correctly masked
off when computing residue in jz4780_dma_desc_residue(). Note that
reads of the DTCn hardware reg are automatically masked this way.

Signed-off-by: Daniel Silsby <dansilsby@xxxxxxxxx>
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Tested-by: Mathieu Malaterre <malat@xxxxxxxxxx>
---
 drivers/dma/dma-jz4780.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

 v2: No change

 v3: No change

 v4: Add my Signed-off-by

diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c
index 3a4d0a4b550d..a4292ac4c686 100644
--- a/drivers/dma/dma-jz4780.c
+++ b/drivers/dma/dma-jz4780.c
@@ -616,7 +616,8 @@ static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan,
 	residue = 0;
 
 	for (i = next_sg; i < desc->count; i++)
-		residue += desc->desc[i].dtc << jzchan->transfer_shift;
+		residue += (desc->desc[i].dtc & 0xffffff) <<
+			jzchan->transfer_shift;
 
 	if (next_sg != 0) {
 		count = jz4780_dma_chn_readl(jzdma, jzchan->id,
-- 
2.11.0

--
To unsubscribe from this list: send the line "unsubscribe dmaengine" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux PCI]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux