From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> [ Upstream commit 9f007e7b6643799e2a6538a5fe04f51c371c6657 ] While the descriptor ID is stored in a 32-bit field in the hardware descriptor, only 16 bits are used by the hardware and are reported through the XILINX_DPDMA_CH_DESC_ID register. Failure to handle the wrap-around results in a descriptor ID mismatch after 65536 frames. Fix it. Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> Tested-by: Jianqiang Chen <jianqiang.chen@xxxxxxxxxx> Reviewed-by: Jianqiang Chen <jianqiang.chen@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210520152420.23986-5-laurent.pinchart@xxxxxxxxxxxxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/dma/xilinx/xilinx_dpdma.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/dma/xilinx/xilinx_dpdma.c b/drivers/dma/xilinx/xilinx_dpdma.c index 70b29bd079c9..249ce3988a59 100644 --- a/drivers/dma/xilinx/xilinx_dpdma.c +++ b/drivers/dma/xilinx/xilinx_dpdma.c @@ -113,6 +113,7 @@ #define XILINX_DPDMA_CH_VDO 0x020 #define XILINX_DPDMA_CH_PYLD_SZ 0x024 #define XILINX_DPDMA_CH_DESC_ID 0x028 +#define XILINX_DPDMA_CH_DESC_ID_MASK GENMASK(15, 0) /* DPDMA descriptor fields */ #define XILINX_DPDMA_DESC_CONTROL_PREEMBLE 0xa5 @@ -866,7 +867,8 @@ static void xilinx_dpdma_chan_queue_transfer(struct xilinx_dpdma_chan *chan) * will be used, but it should be enough. */ list_for_each_entry(sw_desc, &desc->descriptors, node) - sw_desc->hw.desc_id = desc->vdesc.tx.cookie; + sw_desc->hw.desc_id = desc->vdesc.tx.cookie + & XILINX_DPDMA_CH_DESC_ID_MASK; sw_desc = list_first_entry(&desc->descriptors, struct xilinx_dpdma_sw_desc, node); @@ -1086,7 +1088,8 @@ static void xilinx_dpdma_chan_vsync_irq(struct xilinx_dpdma_chan *chan) if (!chan->running || !pending) goto out; - desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID); + desc_id = dpdma_read(chan->reg, XILINX_DPDMA_CH_DESC_ID) + & XILINX_DPDMA_CH_DESC_ID_MASK; /* If the retrigger raced with vsync, retry at the next frame. */ sw_desc = list_first_entry(&pending->descriptors, -- 2.30.2