mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-30 16:13:54 +08:00
d9de451989
This patch adds a cyclic DMA interface to the DW DMA driver. This is very useful if you want to use the DMA controller in combination with a sound device which uses cyclic buffers. Using a DMA channel for cyclic DMA will disable the possibility to use it as a normal DMA engine until the user calls the cyclic free function on the DMA channel. Also a cyclic DMA list can not be prepared if the channel is already active. Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
97 lines
3.0 KiB
C
97 lines
3.0 KiB
C
/*
|
|
* Driver for the Synopsys DesignWare DMA Controller (aka DMACA on
|
|
* AVR32 systems.)
|
|
*
|
|
* Copyright (C) 2007 Atmel Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef DW_DMAC_H
|
|
#define DW_DMAC_H
|
|
|
|
#include <linux/dmaengine.h>
|
|
|
|
/**
|
|
* struct dw_dma_platform_data - Controller configuration parameters
|
|
* @nr_channels: Number of channels supported by hardware (max 8)
|
|
*/
|
|
struct dw_dma_platform_data {
|
|
unsigned int nr_channels;
|
|
};
|
|
|
|
/**
|
|
* enum dw_dma_slave_width - DMA slave register access width.
|
|
* @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
|
|
* @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
|
|
* @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
|
|
*/
|
|
enum dw_dma_slave_width {
|
|
DW_DMA_SLAVE_WIDTH_8BIT,
|
|
DW_DMA_SLAVE_WIDTH_16BIT,
|
|
DW_DMA_SLAVE_WIDTH_32BIT,
|
|
};
|
|
|
|
/**
|
|
* struct dw_dma_slave - Controller-specific information about a slave
|
|
*
|
|
* @dma_dev: required DMA master device
|
|
* @tx_reg: physical address of data register used for
|
|
* memory-to-peripheral transfers
|
|
* @rx_reg: physical address of data register used for
|
|
* peripheral-to-memory transfers
|
|
* @reg_width: peripheral register width
|
|
* @cfg_hi: Platform-specific initializer for the CFG_HI register
|
|
* @cfg_lo: Platform-specific initializer for the CFG_LO register
|
|
*/
|
|
struct dw_dma_slave {
|
|
struct device *dma_dev;
|
|
dma_addr_t tx_reg;
|
|
dma_addr_t rx_reg;
|
|
enum dw_dma_slave_width reg_width;
|
|
u32 cfg_hi;
|
|
u32 cfg_lo;
|
|
};
|
|
|
|
/* Platform-configurable bits in CFG_HI */
|
|
#define DWC_CFGH_FCMODE (1 << 0)
|
|
#define DWC_CFGH_FIFO_MODE (1 << 1)
|
|
#define DWC_CFGH_PROTCTL(x) ((x) << 2)
|
|
#define DWC_CFGH_SRC_PER(x) ((x) << 7)
|
|
#define DWC_CFGH_DST_PER(x) ((x) << 11)
|
|
|
|
/* Platform-configurable bits in CFG_LO */
|
|
#define DWC_CFGL_PRIO(x) ((x) << 5) /* priority */
|
|
#define DWC_CFGL_LOCK_CH_XFER (0 << 12) /* scope of LOCK_CH */
|
|
#define DWC_CFGL_LOCK_CH_BLOCK (1 << 12)
|
|
#define DWC_CFGL_LOCK_CH_XACT (2 << 12)
|
|
#define DWC_CFGL_LOCK_BUS_XFER (0 << 14) /* scope of LOCK_BUS */
|
|
#define DWC_CFGL_LOCK_BUS_BLOCK (1 << 14)
|
|
#define DWC_CFGL_LOCK_BUS_XACT (2 << 14)
|
|
#define DWC_CFGL_LOCK_CH (1 << 15) /* channel lockout */
|
|
#define DWC_CFGL_LOCK_BUS (1 << 16) /* busmaster lockout */
|
|
#define DWC_CFGL_HS_DST_POL (1 << 18) /* dst handshake active low */
|
|
#define DWC_CFGL_HS_SRC_POL (1 << 19) /* src handshake active low */
|
|
|
|
/* DMA API extensions */
|
|
struct dw_cyclic_desc {
|
|
struct dw_desc **desc;
|
|
unsigned long periods;
|
|
void (*period_callback)(void *param);
|
|
void *period_callback_param;
|
|
};
|
|
|
|
struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
|
|
dma_addr_t buf_addr, size_t buf_len, size_t period_len,
|
|
enum dma_data_direction direction);
|
|
void dw_dma_cyclic_free(struct dma_chan *chan);
|
|
int dw_dma_cyclic_start(struct dma_chan *chan);
|
|
void dw_dma_cyclic_stop(struct dma_chan *chan);
|
|
|
|
dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan);
|
|
|
|
dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan);
|
|
|
|
#endif /* DW_DMAC_H */
|