mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-05 02:51:00 +00:00
a0594cefb7
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>
86 lines
2.1 KiB
C
86 lines
2.1 KiB
C
/*
|
|
* (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_ */
|