xref: /openbmc/linux/arch/sh/include/asm/dma.h (revision e8e0929d)
1 /*
2  * include/asm-sh/dma.h
3  *
4  * Copyright (C) 2003, 2004  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #ifndef __ASM_SH_DMA_H
11 #define __ASM_SH_DMA_H
12 #ifdef __KERNEL__
13 
14 #include <linux/spinlock.h>
15 #include <linux/wait.h>
16 #include <linux/sched.h>
17 #include <linux/sysdev.h>
18 #include <cpu/dma.h>
19 #include <asm-generic/dma.h>
20 
21 #ifdef CONFIG_NR_DMA_CHANNELS
22 #  define MAX_DMA_CHANNELS   (CONFIG_NR_DMA_CHANNELS)
23 #else
24 #  define MAX_DMA_CHANNELS   (CONFIG_NR_ONCHIP_DMA_CHANNELS)
25 #endif
26 
27 /*
28  * Read and write modes can mean drastically different things depending on the
29  * channel configuration. Consult your DMAC documentation and module
30  * implementation for further clues.
31  */
32 #define DMA_MODE_READ		0x00
33 #define DMA_MODE_WRITE		0x01
34 #define DMA_MODE_MASK		0x01
35 
36 #define DMA_AUTOINIT		0x10
37 
38 /*
39  * DMAC (dma_info) flags
40  */
41 enum {
42 	DMAC_CHANNELS_CONFIGURED	= 0x01,
43 	DMAC_CHANNELS_TEI_CAPABLE	= 0x02,	/* Transfer end interrupt */
44 };
45 
46 /*
47  * DMA channel capabilities / flags
48  */
49 enum {
50 	DMA_CONFIGURED			= 0x01,
51 
52 	/*
53 	 * Transfer end interrupt, inherited from DMAC.
54 	 * wait_queue used in dma_wait_for_completion.
55 	 */
56 	DMA_TEI_CAPABLE			= 0x02,
57 };
58 
59 extern spinlock_t dma_spin_lock;
60 
61 struct dma_channel;
62 
63 struct dma_ops {
64 	int (*request)(struct dma_channel *chan);
65 	void (*free)(struct dma_channel *chan);
66 
67 	int (*get_residue)(struct dma_channel *chan);
68 	int (*xfer)(struct dma_channel *chan);
69 	int (*configure)(struct dma_channel *chan, unsigned long flags);
70 	int (*extend)(struct dma_channel *chan, unsigned long op, void *param);
71 };
72 
73 struct dma_channel {
74 	char dev_id[16];		/* unique name per DMAC of channel */
75 
76 	unsigned int chan;		/* DMAC channel number */
77 	unsigned int vchan;		/* Virtual channel number */
78 
79 	unsigned int mode;
80 	unsigned int count;
81 
82 	unsigned long sar;
83 	unsigned long dar;
84 
85 	const char **caps;
86 
87 	unsigned long flags;
88 	atomic_t busy;
89 
90 	wait_queue_head_t wait_queue;
91 
92 	struct sys_device dev;
93 	void *priv_data;
94 };
95 
96 struct dma_info {
97 	struct platform_device *pdev;
98 
99 	const char *name;
100 	unsigned int nr_channels;
101 	unsigned long flags;
102 
103 	struct dma_ops *ops;
104 	struct dma_channel *channels;
105 
106 	struct list_head list;
107 	int first_channel_nr;
108 	int first_vchannel_nr;
109 };
110 
111 struct dma_chan_caps {
112 	int ch_num;
113 	const char **caplist;
114 };
115 
116 #define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
117 
118 /* arch/sh/drivers/dma/dma-api.c */
119 extern int dma_xfer(unsigned int chan, unsigned long from,
120 		    unsigned long to, size_t size, unsigned int mode);
121 
122 #define dma_write(chan, from, to, size)	\
123 	dma_xfer(chan, from, to, size, DMA_MODE_WRITE)
124 #define dma_write_page(chan, from, to)	\
125 	dma_write(chan, from, to, PAGE_SIZE)
126 
127 #define dma_read(chan, from, to, size)	\
128 	dma_xfer(chan, from, to, size, DMA_MODE_READ)
129 #define dma_read_page(chan, from, to)	\
130 	dma_read(chan, from, to, PAGE_SIZE)
131 
132 extern int request_dma_bycap(const char **dmac, const char **caps,
133 			     const char *dev_id);
134 extern int get_dma_residue(unsigned int chan);
135 extern struct dma_info *get_dma_info(unsigned int chan);
136 extern struct dma_channel *get_dma_channel(unsigned int chan);
137 extern void dma_wait_for_completion(unsigned int chan);
138 extern void dma_configure_channel(unsigned int chan, unsigned long flags);
139 
140 extern int register_dmac(struct dma_info *info);
141 extern void unregister_dmac(struct dma_info *info);
142 extern struct dma_info *get_dma_info_by_name(const char *dmac_name);
143 
144 extern int dma_extend(unsigned int chan, unsigned long op, void *param);
145 extern int register_chan_caps(const char *dmac, struct dma_chan_caps *capslist);
146 
147 /* arch/sh/drivers/dma/dma-sysfs.c */
148 extern int dma_create_sysfs_files(struct dma_channel *, struct dma_info *);
149 extern void dma_remove_sysfs_files(struct dma_channel *, struct dma_info *);
150 
151 #ifdef CONFIG_PCI
152 extern int isa_dma_bridge_buggy;
153 #else
154 #define isa_dma_bridge_buggy	(0)
155 #endif
156 
157 #endif /* __KERNEL__ */
158 #endif /* __ASM_SH_DMA_H */
159