[PATCH 4.19 071/125] dmaengine: xilinx_dma: Fix control reg update in vdma_channel_set_config

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:44:11 EST


From: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>

[ Upstream commit 6c6de1ddb1be3840f2ed5cc9d009a622720940c9 ]

In vdma_channel_set_config clear the delay, frame count and master mask
before updating their new values. It avoids programming incorrect state
when input parameters are different from default.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
Acked-by: Appana Durga Kedareswara rao <appana.durga.rao@xxxxxxxxxx>
Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1569495060-18117-3-git-send-email-radhey.shyam.pandey@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/xilinx/xilinx_dma.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index c124423125951..8aec137b4fcaa 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -72,6 +72,9 @@
#define XILINX_DMA_DMACR_CIRC_EN BIT(1)
#define XILINX_DMA_DMACR_RUNSTOP BIT(0)
#define XILINX_DMA_DMACR_FSYNCSRC_MASK GENMASK(6, 5)
+#define XILINX_DMA_DMACR_DELAY_MASK GENMASK(31, 24)
+#define XILINX_DMA_DMACR_FRAME_COUNT_MASK GENMASK(23, 16)
+#define XILINX_DMA_DMACR_MASTER_MASK GENMASK(11, 8)

#define XILINX_DMA_REG_DMASR 0x0004
#define XILINX_DMA_DMASR_EOL_LATE_ERR BIT(15)
@@ -2112,8 +2115,10 @@ int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
chan->config.gen_lock = cfg->gen_lock;
chan->config.master = cfg->master;

+ dmacr &= ~XILINX_DMA_DMACR_GENLOCK_EN;
if (cfg->gen_lock && chan->genlock) {
dmacr |= XILINX_DMA_DMACR_GENLOCK_EN;
+ dmacr &= ~XILINX_DMA_DMACR_MASTER_MASK;
dmacr |= cfg->master << XILINX_DMA_DMACR_MASTER_SHIFT;
}

@@ -2129,11 +2134,13 @@ int xilinx_vdma_channel_set_config(struct dma_chan *dchan,
chan->config.delay = cfg->delay;

if (cfg->coalesc <= XILINX_DMA_DMACR_FRAME_COUNT_MAX) {
+ dmacr &= ~XILINX_DMA_DMACR_FRAME_COUNT_MASK;
dmacr |= cfg->coalesc << XILINX_DMA_DMACR_FRAME_COUNT_SHIFT;
chan->config.coalesc = cfg->coalesc;
}

if (cfg->delay <= XILINX_DMA_DMACR_DELAY_MAX) {
+ dmacr &= ~XILINX_DMA_DMACR_DELAY_MASK;
dmacr |= cfg->delay << XILINX_DMA_DMACR_DELAY_SHIFT;
chan->config.delay = cfg->delay;
}
--
2.20.1