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authorMatthias Fend <matthias.fend@wolfvision.net>2020-01-15 13:22:49 +0300
committerVinod Koul <vkoul@kernel.org>2020-01-21 12:19:30 +0300
commitcc88525ebffc757e00cc5a5d61da6271646c7f5f (patch)
treea0a1cd3df6b3fc5280d45cf104a965d0a6fbe7f7 /drivers/dma/xilinx
parentffc079a4accc2bd02758eb93cb8efcb3bfee1891 (diff)
downloadlinux-cc88525ebffc757e00cc5a5d61da6271646c7f5f.tar.xz
dmaengine: zynqmp_dma: fix burst length configuration
Since the dma engine expects the burst length register content as power of 2 value, the burst length needs to be converted first. Additionally add a burst length range check to avoid corrupting unrelated register bits. Signed-off-by: Matthias Fend <matthias.fend@wolfvision.net> Link: https://lore.kernel.org/r/20200115102249.24398-1-matthias.fend@wolfvision.net Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/xilinx')
-rw-r--r--drivers/dma/xilinx/zynqmp_dma.c24
1 files changed, 15 insertions, 9 deletions
diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index 9c845c07b107..d47749a35863 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -123,10 +123,12 @@
/* Max transfer size per descriptor */
#define ZYNQMP_DMA_MAX_TRANS_LEN 0x40000000
+/* Max burst lengths */
+#define ZYNQMP_DMA_MAX_DST_BURST_LEN 32768U
+#define ZYNQMP_DMA_MAX_SRC_BURST_LEN 32768U
+
/* Reset values for data attributes */
#define ZYNQMP_DMA_AXCACHE_VAL 0xF
-#define ZYNQMP_DMA_ARLEN_RST_VAL 0xF
-#define ZYNQMP_DMA_AWLEN_RST_VAL 0xF
#define ZYNQMP_DMA_SRC_ISSUE_RST_VAL 0x1F
@@ -534,17 +536,19 @@ static void zynqmp_dma_handle_ovfl_int(struct zynqmp_dma_chan *chan, u32 status)
static void zynqmp_dma_config(struct zynqmp_dma_chan *chan)
{
- u32 val;
+ u32 val, burst_val;
val = readl(chan->regs + ZYNQMP_DMA_CTRL0);
val |= ZYNQMP_DMA_POINT_TYPE_SG;
writel(val, chan->regs + ZYNQMP_DMA_CTRL0);
val = readl(chan->regs + ZYNQMP_DMA_DATA_ATTR);
+ burst_val = __ilog2_u32(chan->src_burst_len);
val = (val & ~ZYNQMP_DMA_ARLEN) |
- (chan->src_burst_len << ZYNQMP_DMA_ARLEN_OFST);
+ ((burst_val << ZYNQMP_DMA_ARLEN_OFST) & ZYNQMP_DMA_ARLEN);
+ burst_val = __ilog2_u32(chan->dst_burst_len);
val = (val & ~ZYNQMP_DMA_AWLEN) |
- (chan->dst_burst_len << ZYNQMP_DMA_AWLEN_OFST);
+ ((burst_val << ZYNQMP_DMA_AWLEN_OFST) & ZYNQMP_DMA_AWLEN);
writel(val, chan->regs + ZYNQMP_DMA_DATA_ATTR);
}
@@ -560,8 +564,10 @@ static int zynqmp_dma_device_config(struct dma_chan *dchan,
{
struct zynqmp_dma_chan *chan = to_chan(dchan);
- chan->src_burst_len = config->src_maxburst;
- chan->dst_burst_len = config->dst_maxburst;
+ chan->src_burst_len = clamp(config->src_maxburst, 1U,
+ ZYNQMP_DMA_MAX_SRC_BURST_LEN);
+ chan->dst_burst_len = clamp(config->dst_maxburst, 1U,
+ ZYNQMP_DMA_MAX_DST_BURST_LEN);
return 0;
}
@@ -887,8 +893,8 @@ static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
return PTR_ERR(chan->regs);
chan->bus_width = ZYNQMP_DMA_BUS_WIDTH_64;
- chan->dst_burst_len = ZYNQMP_DMA_AWLEN_RST_VAL;
- chan->src_burst_len = ZYNQMP_DMA_ARLEN_RST_VAL;
+ chan->dst_burst_len = ZYNQMP_DMA_MAX_DST_BURST_LEN;
+ chan->src_burst_len = ZYNQMP_DMA_MAX_SRC_BURST_LEN;
err = of_property_read_u32(node, "xlnx,bus-width", &chan->bus_width);
if (err < 0) {
dev_err(&pdev->dev, "missing xlnx,bus-width property\n");