[PATCH AUTOSEL 5.12 04/39] dmaengine: xilinx: dpdma: Limit descriptor IDs to 16 bits
From: Sasha Levin <sashal@kernel.org>
Date: 2021-06-21 17:52:20
Also in:
dmaengine, linux-arm-kernel, lkml
Subsystem:
dma generic offload engine subsystem, the rest, xilinx zynqmp dpdma driver · Maintainers:
Vinod Koul, Linus Torvalds, Laurent Pinchart
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com> [ 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@ideasonboard.com> Tested-by: Jianqiang Chen <redacted> Reviewed-by: Jianqiang Chen <redacted> Link: https://lore.kernel.org/r/20210520152420.23986-5-laurent.pinchart@ideasonboard.com (local) Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- 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