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> --- 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 5834f8614a58..6a8bb977fc7a 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 @@ -867,7 +868,8 @@ 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); @@ -1090,7 +1092,8 @@ 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, -- Regards, Laurent Pinchart
