summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/dma/pl330.c17
1 files changed, 13 insertions, 4 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 4839bfa74a10..81505420bde4 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -2459,16 +2459,25 @@ pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
/* Select max possible burst size */
burst = pl330->pcfg.data_bus_width / 8;
- while (burst > 1) {
- if (!(len % burst))
- break;
+ /*
+ * Make sure we use a burst size that aligns with all the memcpy
+ * parameters because our DMA programming algorithm doesn't cope with
+ * transfers which straddle an entry in the DMA device's MFIFO.
+ */
+ while ((src | dst | len) & (burst - 1))
burst /= 2;
- }
desc->rqcfg.brst_size = 0;
while (burst != (1 << desc->rqcfg.brst_size))
desc->rqcfg.brst_size++;
+ /*
+ * If burst size is smaller than bus width then make sure we only
+ * transfer one at a time to avoid a burst stradling an MFIFO entry.
+ */
+ if (desc->rqcfg.brst_size * 8 < pl330->pcfg.data_bus_width)
+ desc->rqcfg.brst_len = 1;
+
desc->rqcfg.brst_len = get_burst_len(desc, len);
desc->txd.flags = flags;