aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-s3c24xx/include/mach/dma.h
blob: ee99fd56c0439f5bdc22152fa2c530282424fd70 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
/* 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 <linux/device.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_DT_PROP = -1,	/* not yet supported, do not use */
	DMACH_XD0 = 0,
	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_SPI0_TX,		/* s3c2443/2416/2450 hsspi0 */
	DMACH_SPI0_RX,		/* s3c2443/2416/2450 hsspi0 */
	DMACH_SPI1_TX,		/* s3c2443/2450 hsspi1 */
	DMACH_SPI1_RX,		/* s3c2443/2450 hsspi1 */
	DMACH_MAX,		/* the end entry */
};

static inline bool samsung_dma_has_circular(void)
{
	return false;
}

static inline bool samsung_dma_is_dmadev(void)
{
	return false;
}

#include <plat/dma.h>

#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 dma_data_direction	 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 device	dev;
};

typedef unsigned long dma_device_t;

#endif /* __ASM_ARCH_DMA_H */