diff options
author | Mugunthan V N <mugunthanvnm@ti.com> | 2016-02-15 15:31:37 +0530 |
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committer | Jagan Teki <jteki@openedev.com> | 2016-02-23 16:14:45 +0530 |
commit | a0594cefb7682dc0c32084d088b3ac0a85ed7395 (patch) | |
tree | fa70110c909901dc0c8258168e982d5b03c5beb0 /include | |
parent | 18c61e95714f4a18f1a206369fc187639d9845e1 (diff) | |
download | u-boot-imx-a0594cefb7682dc0c32084d088b3ac0a85ed7395.zip u-boot-imx-a0594cefb7682dc0c32084d088b3ac0a85ed7395.tar.gz u-boot-imx-a0594cefb7682dc0c32084d088b3ac0a85ed7395.tar.bz2 |
dm: implement a DMA uclass
Implement a DMA uclass so that the devices like ethernet, spi,
mmc etc can offload the data transfers from/to the device and
memory.
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagan Teki <jteki@openedev.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/dm/uclass-id.h | 1 | ||||
-rw-r--r-- | include/dma.h | 86 |
2 files changed, 87 insertions, 0 deletions
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 73cd3ac..3bea308 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -31,6 +31,7 @@ enum uclass_id { UCLASS_CROS_EC, /* Chrome OS EC */ UCLASS_DISK, /* Disk controller, e.g. SATA */ UCLASS_DISPLAY, /* Display (e.g. DisplayPort, HDMI) */ + UCLASS_DMA, /* Direct Memory Access */ UCLASS_RAM, /* RAM controller */ UCLASS_ETH, /* Ethernet device */ UCLASS_GPIO, /* Bank of general-purpose I/O pins */ diff --git a/include/dma.h b/include/dma.h new file mode 100644 index 0000000..71fa77f --- /dev/null +++ b/include/dma.h @@ -0,0 +1,86 @@ +/* + * (C) Copyright 2015 + * Texas Instruments Incorporated, <www.ti.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _DMA_H_ +#define _DMA_H_ + +/* + * enum dma_direction - dma transfer direction indicator + * @DMA_MEM_TO_MEM: Memcpy mode + * @DMA_MEM_TO_DEV: From Memory to Device + * @DMA_DEV_TO_MEM: From Device to Memory + * @DMA_DEV_TO_DEV: From Device to Device + */ +enum dma_direction { + DMA_MEM_TO_MEM, + DMA_MEM_TO_DEV, + DMA_DEV_TO_MEM, + DMA_DEV_TO_DEV, +}; + +#define DMA_SUPPORTS_MEM_TO_MEM BIT(0) +#define DMA_SUPPORTS_MEM_TO_DEV BIT(1) +#define DMA_SUPPORTS_DEV_TO_MEM BIT(2) +#define DMA_SUPPORTS_DEV_TO_DEV BIT(3) + +/* + * struct dma_ops - Driver model DMA operations + * + * The uclass interface is implemented by all DMA devices which use + * driver model. + */ +struct dma_ops { + /* + * Get the current timer count + * + * @dev: The DMA device + * @direction: direction of data transfer should be one from + enum dma_direction + * @dst: Destination pointer + * @src: Source pointer + * @len: Length of the data to be copied. + * @return: 0 if OK, -ve on error + */ + int (*transfer)(struct udevice *dev, int direction, void *dst, + void *src, size_t len); +}; + +/* + * struct dma_dev_priv - information about a device used by the uclass + * + * @supported: mode of transfers that DMA can support, should be + * one/multiple of DMA_SUPPORTS_* + */ +struct dma_dev_priv { + u32 supported; +}; + +/* + * dma_get_device - get a DMA device which supports transfer + * type of transfer_type + * + * @transfer_type - transfer type should be one/multiple of + * DMA_SUPPORTS_* + * @devp - udevice pointer to return the found device + * @return - will return on success and devp will hold the + * pointer to the device + */ +int dma_get_device(u32 transfer_type, struct udevice **devp); + +/* + * dma_memcpy - try to use DMA to do a mem copy which will be + * much faster than CPU mem copy + * + * @dst - destination pointer + * @src - souce pointer + * @len - data length to be copied + * @return - on successful transfer returns no of bytes + transferred and on failure return error code. + */ +int dma_memcpy(void *dst, void *src, size_t len); + +#endif /* _DMA_H_ */ |