From 56009f0d2f54e4ce4305d65ce589eee6c22ac25f Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 26 Mar 2019 15:06:28 +0200 Subject: [PATCH] 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 Use this information as it is more reliably than the information specified in the devicetree which might be outdated if the HDL project got changed.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 Signed-off-by: Alexandru Ardelean Signed-off-by: Vinod Koul --- .../devicetree/bindings/dma/adi,axi-dmac.txt | 4 +-- drivers/dma/dma-axi-dmac.c | 32 ++++++++++++------- 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 47cb1d14b690f0..b38ee732efa9fd 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 0fe3a931d8d539..eecb367b4f3e42 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);