summaryrefslogtreecommitdiffstats
path: root/arch/mips/alchemy/common/dma.c
blob: 9b624e2c0fcf8be6703debf45fa948e1d5e6eff0 (plain)
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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
/*
 *
 * BRIEF MODULE DESCRIPTION
 *      A DMA channel allocator for Au1x00. API is modeled loosely off of
 *      linux/kernel/dma.c.
 *
 * Copyright 2000, 2008 MontaVista Software Inc.
 * Author: MontaVista Software, Inc. <source@mvista.com>
 * Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
 *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
 *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  You should have received a copy of the  GNU General Public License along
 *  with this program; if not, write  to the Free Software Foundation, Inc.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>

#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/au1000_dma.h>

/*
 * A note on resource allocation:
 *
 * All drivers needing DMA channels, should allocate and release them
 * through the public routines `request_dma()' and `free_dma()'.
 *
 * In order to avoid problems, all processes should allocate resources in
 * the same sequence and release them in the reverse order.
 *
 * So, when allocating DMAs and IRQs, first allocate the DMA, then the IRQ.
 * When releasing them, first release the IRQ, then release the DMA. The
 * main reason for this order is that, if you are requesting the DMA buffer
 * done interrupt, you won't know the irq number until the DMA channel is
 * returned from request_dma.
 */

/* DMA Channel register block spacing */
#define DMA_CHANNEL_LEN		0x00000100

DEFINE_SPINLOCK(au1000_dma_spin_lock);

struct dma_chan au1000_dma_table[NUM_AU1000_DMA_CHANNELS] = {
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,},
      {.dev_id = -1,}
};
EXPORT_SYMBOL(au1000_dma_table);

/* Device FIFO addresses and default DMA modes */
static const struct dma_dev {
	unsigned int fifo_addr;
	unsigned int dma_mode;
} dma_dev_table[DMA_NUM_DEV] = {
	{ AU1000_UART0_PHYS_ADDR + 0x04, DMA_DW8 },		/* UART0_TX */
	{ AU1000_UART0_PHYS_ADDR + 0x00, DMA_DW8 | DMA_DR },	/* UART0_RX */
	{ 0, 0 },	/* DMA_REQ0 */
	{ 0, 0 },	/* DMA_REQ1 */
	{ AU1000_AC97_PHYS_ADDR + 0x08, DMA_DW16 },		/* AC97 TX c */
	{ AU1000_AC97_PHYS_ADDR + 0x08, DMA_DW16 | DMA_DR },	/* AC97 RX c */
	{ AU1000_UART3_PHYS_ADDR + 0x04, DMA_DW8 | DMA_NC },	/* UART3_TX */
	{ AU1000_UART3_PHYS_ADDR + 0x00, DMA_DW8 | DMA_NC | DMA_DR }, /* UART3_RX */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x00, DMA_DW8 | DMA_NC | DMA_DR }, /* EP0RD */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x04, DMA_DW8 | DMA_NC }, /* EP0WR */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x08, DMA_DW8 | DMA_NC }, /* EP2WR */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x0c, DMA_DW8 | DMA_NC }, /* EP3WR */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x10, DMA_DW8 | DMA_NC | DMA_DR }, /* EP4RD */
	{ AU1000_USB_UDC_PHYS_ADDR + 0x14, DMA_DW8 | DMA_NC | DMA_DR }, /* EP5RD */
	/* on Au1500, these 2 are DMA_REQ2/3 (GPIO208/209) instead! */
	{ AU1000_I2S_PHYS_ADDR + 0x00, DMA_DW32 | DMA_NC},	/* I2S TX */
	{ AU1000_I2S_PHYS_ADDR + 0x00, DMA_DW32 | DMA_NC | DMA_DR}, /* I2S RX */
};

int au1000_dma_read_proc(char *buf, char **start, off_t fpos,
			 int length, int *eof, void *data)
{
	int i, len = 0;
	struct dma_chan *chan;

	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
		chan = get_dma_chan(i);
		if (chan != NULL)
			len += sprintf(buf + len, "%2d: %s\n",
				       i, chan->dev_str);
	}

	if (fpos >= len) {
		*start = buf;
		*eof = 1;
		return 0;
	}
	*start = buf + fpos;
	len -= fpos;
	if (len > length)
		return length;
	*eof = 1;
	return len;
}

/* Device FIFO addresses and default DMA modes - 2nd bank */
static const struct dma_dev dma_dev_table_bank2[DMA_NUM_DEV_BANK2] = {
	{ AU1100_SD0_PHYS_ADDR + 0x00, DMA_DS | DMA_DW8 },		/* coherent */
	{ AU1100_SD0_PHYS_ADDR + 0x04, DMA_DS | DMA_DW8 | DMA_DR },	/* coherent */
	{ AU1100_SD1_PHYS_ADDR + 0x00, DMA_DS | DMA_DW8 },		/* coherent */
	{ AU1100_SD1_PHYS_ADDR + 0x04, DMA_DS | DMA_DW8 | DMA_DR }	/* coherent */
};

void dump_au1000_dma_channel(unsigned int dmanr)
{
	struct dma_chan *chan;

	if (dmanr >= NUM_AU1000_DMA_CHANNELS)
		return;
	chan = &au1000_dma_table[dmanr];

	printk(KERN_INFO "Au1000 DMA%d Register Dump:\n", dmanr);
	printk(KERN_INFO "  mode = 0x%08x\n",
	       au_readl(chan->io + DMA_MODE_SET));
	printk(KERN_INFO "  addr = 0x%08x\n",
	       au_readl(chan->io + DMA_PERIPHERAL_ADDR));
	printk(KERN_INFO "  start0 = 0x%08x\n",
	       au_readl(chan->io + DMA_BUFFER0_START));
	printk(KERN_INFO "  start1 = 0x%08x\n",
	       au_readl(chan->io + DMA_BUFFER1_START));
	printk(KERN_INFO "  count0 = 0x%08x\n",
	       au_readl(chan->io + DMA_BUFFER0_COUNT));
	printk(KERN_INFO "  count1 = 0x%08x\n",
	       au_readl(chan->io + DMA_BUFFER1_COUNT));
}

/*
 * Finds a free channel, and binds the requested device to it.
 * Returns the allocated channel number, or negative on error.
 * Requests the DMA done IRQ if irqhandler != NULL.
 */
int request_au1000_dma(int dev_id, const char *dev_str,
		       irq_handler_t irqhandler,
		       unsigned long irqflags,
		       void *irq_dev_id)
{
	struct dma_chan *chan;
	const struct dma_dev *dev;
	int i, ret;

	if (alchemy_get_cputype() == ALCHEMY_CPU_AU1100) {
		if (dev_id < 0 || dev_id >= (DMA_NUM_DEV + DMA_NUM_DEV_BANK2))
			return -EINVAL;
	} else {
		if (dev_id < 0 || dev_id >= DMA_NUM_DEV)
			return -EINVAL;
	}

	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++)
		if (au1000_dma_table[i].dev_id < 0)
			break;

	if (i == NUM_AU1000_DMA_CHANNELS)
		return -ENODEV;

	chan = &au1000_dma_table[i];

	if (dev_id >= DMA_NUM_DEV) {
		dev_id -= DMA_NUM_DEV;
		dev = &dma_dev_table_bank2[dev_id];
	} else
		dev = &dma_dev_table[dev_id];

	if (irqhandler) {
		chan->irq_dev = irq_dev_id;
		ret = request_irq(chan->irq, irqhandler, irqflags, dev_str,
				  chan->irq_dev);
		if (ret) {
			chan->irq_dev = NULL;
			return ret;
		}
	} else {
		chan->irq_dev = NULL;
	}

	/* fill it in */
	chan->io = KSEG1ADDR(AU1000_DMA_PHYS_ADDR) + i * DMA_CHANNEL_LEN;
	chan->dev_id = dev_id;
	chan->dev_str = dev_str;
	chan->fifo_addr = dev->fifo_addr;
	chan->mode = dev->dma_mode;

	/* initialize the channel before returning */
	init_dma(i);

	return i;
}
EXPORT_SYMBOL(request_au1000_dma);

void free_au1000_dma(unsigned int dmanr)
{
	struct dma_chan *chan = get_dma_chan(dmanr);

	if (!chan) {
		printk(KERN_ERR "Error trying to free DMA%d\n", dmanr);
		return;
	}

	disable_dma(dmanr);
	if (chan->irq_dev)
		free_irq(chan->irq, chan->irq_dev);

	chan->irq_dev = NULL;
	chan->dev_id = -1;
}
EXPORT_SYMBOL(free_au1000_dma);

static int __init au1000_dma_init(void)
{
	int base, i;

	switch (alchemy_get_cputype()) {
	case ALCHEMY_CPU_AU1000:
		base = AU1000_DMA_INT_BASE;
		break;
	case ALCHEMY_CPU_AU1500:
		base = AU1500_DMA_INT_BASE;
		break;
	case ALCHEMY_CPU_AU1100:
		base = AU1100_DMA_INT_BASE;
		break;
	default:
		goto out;
	}

	for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++)
		au1000_dma_table[i].irq = base + i;

	printk(KERN_INFO "Alchemy DMA initialized\n");

out:
	return 0;
}
arch_initcall(au1000_dma_init);
OpenPOWER on IntegriCloud