From: Matthias Fend <matthias.fend@xxxxxxxxxxxxxx> [ Upstream commit cc88525ebffc757e00cc5a5d61da6271646c7f5f ] 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@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200115102249.24398-1-matthias.fend@xxxxxxxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/dma/xilinx/zynqmp_dma.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c index 73de6a6179fcd..e002ff8413e2a 100644 --- a/drivers/dma/xilinx/zynqmp_dma.c +++ b/drivers/dma/xilinx/zynqmp_dma.c @@ -127,10 +127,12 @@ /* 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 @@ -536,17 +538,19 @@ 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); } @@ -562,8 +566,10 @@ 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; } @@ -884,8 +890,8 @@ 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"); -- 2.25.1
