diff options
| author | Mathias Tausen <mta@satlab.com> | 2022-07-26 16:02:12 +0200 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2022-07-26 22:05:20 +0530 |
| commit | 9327c7e7539371c6f202303d5539afbae006ec72 (patch) | |
| tree | 431f1fbeffc3554b998c0f743da39ba8a3adaea2 /drivers/dma | |
| parent | 7d3a3aaaa9cc8ec53e9ef4f3e1711827107f76c5 (diff) | |
dmaengine: axi-dmac: check cache coherency register
Marking the DMA as cache coherent (dma-coherent in devicetree) is only
safe with versions of axi_dmac that have this feature enabled.
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Vinod Koul <vkoul@kernel.org>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Mathias Tausen <mta@satlab.com>
Link: https://lore.kernel.org/r/20220726140213.786939-1-mta@satlab.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/dma-axi-dmac.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c index 5161b73c30c4..f30dabc99795 100644 --- a/drivers/dma/dma-axi-dmac.c +++ b/drivers/dma/dma-axi-dmac.c @@ -18,6 +18,7 @@ #include <linux/module.h> #include <linux/of.h> #include <linux/of_dma.h> +#include <linux/of_address.h> #include <linux/platform_device.h> #include <linux/regmap.h> #include <linux/slab.h> @@ -55,6 +56,9 @@ #define AXI_DMAC_DMA_DST_TYPE_GET(x) FIELD_GET(AXI_DMAC_DMA_DST_TYPE_MSK, x) #define AXI_DMAC_DMA_DST_WIDTH_MSK GENMASK(3, 0) #define AXI_DMAC_DMA_DST_WIDTH_GET(x) FIELD_GET(AXI_DMAC_DMA_DST_WIDTH_MSK, x) +#define AXI_DMAC_REG_COHERENCY_DESC 0x14 +#define AXI_DMAC_DST_COHERENT_MSK BIT(0) +#define AXI_DMAC_DST_COHERENT_GET(x) FIELD_GET(AXI_DMAC_DST_COHERENT_MSK, x) #define AXI_DMAC_REG_IRQ_MASK 0x80 #define AXI_DMAC_REG_IRQ_PENDING 0x84 @@ -979,6 +983,18 @@ static int axi_dmac_probe(struct platform_device *pdev) axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00); + if (of_dma_is_coherent(pdev->dev.of_node)) { + ret = axi_dmac_read(dmac, AXI_DMAC_REG_COHERENCY_DESC); + + if (version < ADI_AXI_PCORE_VER(4, 4, 'a') || + !AXI_DMAC_DST_COHERENT_GET(ret)) { + dev_err(dmac->dma_dev.dev, + "Coherent DMA not supported in hardware"); + ret = -EINVAL; + goto err_clk_disable; + } + } + ret = dma_async_device_register(dma_dev); if (ret) goto err_clk_disable; |