[PATCH v1 04/23] ata: sata_dwc_460ex: burst size must be in items not bytes

Andy Shevchenko andriy.shevchenko at linux.intel.com
Fri Apr 22 04:15:25 AEST 2016


The burst size as defined by DMAengine API is in items of address width. Derive
burst size from AHB_DMA_BRST_DFLT (64 bytes) by dividing it to
DMA_SLAVE_BUSWIDTH_4_BYTES (4 bytes) that gives us 16 items.

Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
---
 drivers/ata/sata_dwc_460ex.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c
index aee8873..4cac27d 100644
--- a/drivers/ata/sata_dwc_460ex.c
+++ b/drivers/ata/sata_dwc_460ex.c
@@ -65,7 +65,7 @@
 #define NO_IRQ		0
 #endif
 
-#define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length*/
+#define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length */
 
 enum {
 	SATA_DWC_MAX_PORTS = 1,
@@ -318,8 +318,8 @@ static struct dma_async_tx_descriptor *dma_dwc_xfer_setup(struct ata_queued_cmd
 	}
 
 	sconf.direction = qc->dma_dir;
-	sconf.src_maxburst = AHB_DMA_BRST_DFLT;
-	sconf.dst_maxburst = AHB_DMA_BRST_DFLT;
+	sconf.src_maxburst = AHB_DMA_BRST_DFLT / 4;	/* in items */
+	sconf.dst_maxburst = AHB_DMA_BRST_DFLT / 4;	/* in items */
 	sconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 	sconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 
-- 
2.8.0.rc3



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