diff options
| author | Andrea Merello <andrea.merello@gmail.com> | 2018-11-20 16:31:49 +0100 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2019-01-07 09:53:12 +0530 |
| commit | 05f7ea7f6ef611a077fcbb983fb8d6a99e91e1f6 (patch) | |
| tree | d2e03103101f54b9161f01d839953dfcad229048 /drivers/dma | |
| parent | ae809690b46a71dc56cda5b3b8884c8c41a0df15 (diff) | |
dmaengine: xilinx_dma: autodetect whether the HW supports scatter-gather
The AXIDMA and CDMA HW can be either direct-access or scatter-gather
version. These are SW incompatible.
The driver can handle both versions: a DT property was used to
tell the driver whether to assume the HW is in scatter-gather mode.
This patch makes the driver to autodetect this information. The DT
property is not required anymore.
No changes for VDMA.
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/xilinx/xilinx_dma.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index d59af2b33a99..b559efe06adb 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -86,6 +86,7 @@ #define XILINX_DMA_DMASR_DMA_DEC_ERR BIT(6) #define XILINX_DMA_DMASR_DMA_SLAVE_ERR BIT(5) #define XILINX_DMA_DMASR_DMA_INT_ERR BIT(4) +#define XILINX_DMA_DMASR_SG_MASK BIT(3) #define XILINX_DMA_DMASR_IDLE BIT(1) #define XILINX_DMA_DMASR_HALTED BIT(0) #define XILINX_DMA_DMASR_DELAY_MASK GENMASK(31, 24) @@ -414,7 +415,6 @@ struct xilinx_dma_config { * @dev: Device Structure * @common: DMA device structure * @chan: Driver specific DMA channel - * @has_sg: Specifies whether Scatter-Gather is present or not * @mcdma: Specifies whether Multi-Channel is present or not * @flush_on_fsync: Flush on frame sync * @ext_addr: Indicates 64 bit addressing is supported by dma device @@ -434,7 +434,6 @@ struct xilinx_dma_device { struct device *dev; struct dma_device common; struct xilinx_dma_chan *chan[XILINX_DMA_MAX_CHANS_PER_DEVICE]; - bool has_sg; bool mcdma; u32 flush_on_fsync; bool ext_addr; @@ -2421,7 +2420,6 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev, chan->dev = xdev->dev; chan->xdev = xdev; - chan->has_sg = xdev->has_sg; chan->desc_pendingcount = 0x0; chan->ext_addr = xdev->ext_addr; /* This variable ensures that descriptors are not @@ -2521,6 +2519,15 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev, chan->stop_transfer = xilinx_dma_stop_transfer; } + /* check if SG is enabled (only for AXIDMA and CDMA) */ + if (xdev->dma_config->dmatype != XDMA_TYPE_VDMA) { + if (dma_ctrl_read(chan, XILINX_DMA_REG_DMASR) & + XILINX_DMA_DMASR_SG_MASK) + chan->has_sg = true; + dev_dbg(chan->dev, "ch %d: SG %s\n", chan->id, + chan->has_sg ? "enabled" : "disabled"); + } + /* Initialize the tasklet */ tasklet_init(&chan->tasklet, xilinx_dma_do_tasklet, (unsigned long)chan); @@ -2659,7 +2666,6 @@ static int xilinx_dma_probe(struct platform_device *pdev) return PTR_ERR(xdev->regs); /* Retrieve the DMA engine properties from the device tree */ - xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg"); xdev->max_buffer_len = GENMASK(XILINX_DMA_MAX_TRANS_LEN_MAX - 1, 0); if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) { |