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authorLars-Peter Clausen <lars@metafoo.de>2019-03-26 15:06:28 +0200
committerVinod Koul <vkoul@kernel.org>2019-04-24 11:04:09 +0530
commit56009f0d2f54e4ce4305d65ce589eee6c22ac25f (patch)
tree55cdf9644bc0d9ea4045d16514f4cec4e9f5208c /drivers/dma
parent38a829a389e33d571a3c599fa762d88b3d1f72c4 (diff)
downloadlinux-56009f0d2f54e4ce4305d65ce589eee6c22ac25f.tar.gz
dmaengine: axi-dmac: Infer synthesis configuration parameters hardware
Some synthesis time configuration parameters of the DMA controller can be inferred from the hardware itself. Use this information as it is more reliably than the information specified in the devicetree which might be outdated if the HDL project got changed. Deprecate the devicetree properties that can be inferred from the hardware itself. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/dma-axi-dmac.c32
1 files changed, 20 insertions, 12 deletions
diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c
index 0fe3a931d8d5..eecb367b4f3e 100644
--- a/drivers/dma/dma-axi-dmac.c
+++ b/drivers/dma/dma-axi-dmac.c
@@ -618,15 +618,6 @@ static int axi_dmac_parse_chan_dt(struct device_node *of_chan,
return ret;
chan->dest_width = val / 8;
- ret = of_property_read_u32(of_chan, "adi,length-width", &val);
- if (ret)
- return ret;
-
- if (val >= 32)
- chan->max_length = UINT_MAX;
- else
- chan->max_length = (1ULL << val) - 1;
-
chan->align_mask = max(chan->dest_width, chan->src_width) - 1;
if (axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
@@ -638,12 +629,27 @@ static int axi_dmac_parse_chan_dt(struct device_node *of_chan,
else
chan->direction = DMA_DEV_TO_DEV;
- chan->hw_cyclic = of_property_read_bool(of_chan, "adi,cyclic");
- chan->hw_2d = of_property_read_bool(of_chan, "adi,2d");
-
return 0;
}
+static void axi_dmac_detect_caps(struct axi_dmac *dmac)
+{
+ struct axi_dmac_chan *chan = &dmac->chan;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_FLAGS, AXI_DMAC_FLAG_CYCLIC);
+ if (axi_dmac_read(dmac, AXI_DMAC_REG_FLAGS) == AXI_DMAC_FLAG_CYCLIC)
+ chan->hw_cyclic = true;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_Y_LENGTH, 1);
+ if (axi_dmac_read(dmac, AXI_DMAC_REG_Y_LENGTH) == 1)
+ chan->hw_2d = true;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, 0xffffffff);
+ chan->max_length = axi_dmac_read(dmac, AXI_DMAC_REG_X_LENGTH);
+ if (chan->max_length != UINT_MAX)
+ chan->max_length++;
+}
+
static int axi_dmac_probe(struct platform_device *pdev)
{
struct device_node *of_channels, *of_chan;
@@ -716,6 +722,8 @@ static int axi_dmac_probe(struct platform_device *pdev)
if (ret < 0)
return ret;
+ axi_dmac_detect_caps(dmac);
+
axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00);
ret = dma_async_device_register(dma_dev);