[PATCH v2 2/4] dmaengine: at_xdmac: adapt perid for mem2mem operations

Eugen Hristev eugen.hristev at microchip.com
Fri Oct 16 05:37:25 EDT 2020


The PERID in the CC register for mem2mem operations must match an unused
PERID.
The PERID field is 7 bits, but the selected value is 0x3f.
On later products we can have more reserved PERIDs for actual peripherals,
thus this needs to be increased to maximum size.
Changing the value to 0x7f, which is the maximum for 7 bits field.

Signed-off-by: Eugen Hristev <eugen.hristev at microchip.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus at microchip.com>
---
Changes in v2:
- no changes

 drivers/dma/at_xdmac.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index fd92f048c491..94f7023472bb 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -867,7 +867,7 @@ at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
 	 * match the one of another channel. If not, it could lead to spurious
 	 * flag status.
 	 */
-	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
+	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
 					| AT_XDMAC_CC_DIF(0)
 					| AT_XDMAC_CC_SIF(0)
 					| AT_XDMAC_CC_MBSIZE_SIXTEEN
@@ -1049,7 +1049,7 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 	 * match the one of another channel. If not, it could lead to spurious
 	 * flag status.
 	 */
-	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
+	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
 					| AT_XDMAC_CC_DAM_INCREMENTED_AM
 					| AT_XDMAC_CC_SAM_INCREMENTED_AM
 					| AT_XDMAC_CC_DIF(0)
@@ -1155,7 +1155,7 @@ static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
 	 * match the one of another channel. If not, it could lead to spurious
 	 * flag status.
 	 */
-	u32			chan_cc = AT_XDMAC_CC_PERID(0x3f)
+	u32			chan_cc = AT_XDMAC_CC_PERID(0x7f)
 					| AT_XDMAC_CC_DAM_UBS_AM
 					| AT_XDMAC_CC_SAM_INCREMENTED_AM
 					| AT_XDMAC_CC_DIF(0)
-- 
2.25.1




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