/* arch/arm/mach-s3c2410/include/mach/dma.h
*
* Copyright (C) 2003-2006 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* Samsung S3C24XX DMA support
*
* 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 __ASM_ARCH_DMA_H
#define __ASM_ARCH_DMA_H __FILE__
#include <plat/dma.h>
#include <linux/sysdev.h>
#define MAX_DMA_TRANSFER_SIZE 0x100000 /* Data Unit is half word */
/* We use `virtual` dma channels to hide the fact we have only a limited
* number of DMA channels, and not of all of them (dependent on the device)
* can be attached to any DMA source. We therefore let the DMA core handle
* the allocation of hardware channels to clients.
*/
enum dma_ch {
DMACH_XD0,
DMACH_XD1,
DMACH_SDI,
DMACH_SPI0,
DMACH_SPI1,
DMACH_UART0,
DMACH_UART1,
DMACH_UART2,
DMACH_TIMER,
DMACH_I2S_IN,
DMACH_I2S_OUT,
DMACH_PCM_IN,
DMACH_PCM_OUT,
DMACH_MIC_IN,
DMACH_USB_EP1,
DMACH_USB_EP2,
DMACH_USB_EP3,
DMACH_USB_EP4,
DMACH_UART0_SRC2, /* s3c2412 second uart sources */
DMACH_UART1_SRC2,
DMACH_UART2_SRC2,
DMACH_UART3, /* s3c2443 has extra uart */
DMACH_UART3_SRC2,
DMACH_MAX, /* the end entry */
};
#define DMACH_LOW_LEVEL (1<<28) /* use this to specifiy hardware ch no */
/* we have 4 dma channels */
#if !defined(CONFIG_CPU_S3C2443) && !defined(CONFIG_CPU_S3C2416)
#define S3C_DMA_CHANNELS (4)
#else
#define S3C_DMA_CHANNELS (6)
#endif
/* types */
enum s3c2410_dma_state {
S3C2410_DMA_IDLE,
S3C2410_DMA_RUNNING,
S3C2410_DMA_PAUSED
};
/* enum s3c2410_dma_loadst
*
* This represents the state of the DMA engine, wrt to the loaded / running
* transfers. Since we don't have any way of knowing exactly the state of
* the DMA transfers, we need to know the state to make decisions on wether
* we can
*
* S3C2410_DMA_NONE
*
* There are no buffers loaded (the channel should be inactive)
*
* S3C2410_DMA_1LOADED
*
* There is one buffer loaded, however it has not been confirmed to be
* loaded by the DMA engine. This may be because the channel is not
* yet running, or the DMA driver decided that it was too costly to
* sit and wait for it to happen.
*
* S3C2410_DMA_1RUNNING
*
* The buffer has been confirmed running, and not finisged
*
* S3C2410_DMA_1LOADED_1RUNNING
*
* There is a buffer waiting to be loaded by the DMA engine, and one
* currently running.
*/
enum s3c2410_dma_loadst {
S3C2410_DMALOAD_NONE,
S3C2410_DMALOAD_1LOADED,
S3C2410_DMALOAD_1RUNNING,
S3C2410_DMALOAD_1LOADED_1RUNNING,
};
/* flags */
#define S3C2410_DMAF_SLOW (1<<0) /* slow, so don't worry about
* waiting for reloads */
#define S3C2410_DMAF_AUTOSTART (1<<1) /* auto-start if buffer queued */
#define S3C2410_DMAF_CIRCULAR (1 << 2) /* no circular dma support */
/* dma buffer */
struct s3c2410_dma_buf;
/* s3c2410_dma_buf
*
* internally used buffer structure to describe a queued or running
* buffer.
*/
struct s3c2410_dma_buf {
struct s3c2410_dma_buf *next;
int magic; /* magic */
int size; /* buffer size in bytes */
dma_addr_t data; /* start of DMA data */
dma_addr_t ptr; /* where the DMA got to [1] */
void *id; /* client's id */
};
/* [1] is this updated for both recv/send modes? */
struct s3c2410_dma_stats {
unsigned long loads;
unsigned long timeout_longest;
unsigned long timeout_shortest;
unsigned long timeout_avg;
unsigned long timeout_failed;
};
struct s3c2410_dma_map;
/* struct s3c2410_dma_chan
*
* full state information for each DMA channel
*/
struct s3c2410_dma_chan {
/* channel state flags and information */
unsigned char number; /* number of this dma channel */
unsigned char in_use; /* channel allocated */
unsigned char irq_claimed; /* irq claimed for channel */
unsigned char irq_enabled; /* irq enabled for channel */
unsigned char xfer_unit; /* size of an transfer */
/* channel state */
enum s3c2410_dma_state state;
enum s3c2410_dma_loadst load_state;
struct s3c2410_dma_client *client;
/* channel configuration */
enum s3c2410_dmasrc source;
enum dma_ch req_ch;
unsigned long dev_addr;
unsigned long load_timeout;
unsigned int flags; /* channel flags */
struct s3c24xx_dma_map *map; /* channel hw maps */
/* channel's hardware position and configuration */
void __iomem *regs; /* channels registers */
void __iomem *addr_reg; /* data address register */
unsigned int irq; /* channel irq */
unsigned long dcon; /* default value of DCON */
/* driver handles */
s3c2410_dma_cbfn_t callback_fn; /* buffer done callback */
s3c2410_dma_opfn_t op_fn; /* channel op callback */
/* stats gathering */
struct s3c2410_dma_stats *stats;
struct s3c2410_dma_stats stats_store;
/* buffer list and information */
struct s3c2410_dma_buf *curr; /* current dma buffer */
struct s3c2410_dma_buf *next; /* next buffer to load */
struct s3c2410_dma_buf *end; /* end of queue */
/* system device */
struct sys_device dev;
};
typedef unsigned long dma_device_t;
static inline bool s3c_dma_has_circular(void)
{
return false;
}
#endif /* __ASM_ARCH_DMA_H */
