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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
parent38a829a389e33d571a3c599fa762d88b3d1f72c4 (diff)
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 Use this information as it is more reliably than the information specified in the devicetree which might be outdated if the HDL project got changed.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>
-rw-r--r--Documentation/devicetree/bindings/dma/adi,axi-dmac.txt4
-rw-r--r--drivers/dma/dma-axi-dmac.c32
2 files changed, 22 insertions, 14 deletions
diff --git a/Documentation/devicetree/bindings/dma/adi,axi-dmac.txt b/Documentation/devicetree/bindings/dma/adi,axi-dmac.txt
index 47cb1d14b690..b38ee732efa9 100644
--- a/Documentation/devicetree/bindings/dma/adi,axi-dmac.txt
+++ b/Documentation/devicetree/bindings/dma/adi,axi-dmac.txt
@@ -18,7 +18,6 @@ Required properties for adi,channels sub-node:
Required channel sub-node properties:
- reg: Which channel this node refers to.
- - adi,length-width: Width of the DMA transfer length register.
- adi,source-bus-width,
adi,destination-bus-width: Width of the source or destination bus in bits.
- adi,source-bus-type,
@@ -28,7 +27,8 @@ Required channel sub-node properties:
1 (AXI_DMAC_TYPE_AXI_STREAM): Streaming AXI interface
2 (AXI_DMAC_TYPE_AXI_FIFO): FIFO interface
-Optional channel properties:
+Deprecated optional channel properties:
+ - adi,length-width: Width of the DMA transfer length register.
- adi,cyclic: Must be set if the channel supports hardware cyclic DMA
transfers.
- adi,2d: Must be set if the channel supports hardware 2D DMA transfers.
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);