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
|
/*
*
* BRIEF MODULE DESCRIPTION
* A DMA channel allocator for Au1000. API is modeled loosely off of
* linux/kernel/dma.c.
*
* Copyright 2000 MontaVista Software Inc.
* Author: MontaVista Software, Inc.
* stevel@mvista.com or 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/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <asm/system.h>
#include <asm/mach-au1x00/au1000.h>
#include <asm/mach-au1x00/au1000_dma.h>
#if defined(CONFIG_SOC_AU1000) || defined(CONFIG_SOC_AU1500) || defined(CONFIG_SOC_AU1100)
/*
* 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.
*/
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] = {
{UART0_ADDR + UART_TX, 0},
{UART0_ADDR + UART_RX, 0},
{0, 0},
{0, 0},
{AC97C_DATA, DMA_DW16 }, // coherent
{AC97C_DATA, DMA_DR | DMA_DW16 }, // coherent
{UART3_ADDR + UART_TX, DMA_DW8 | DMA_NC},
{UART3_ADDR + UART_RX, DMA_DR | DMA_DW8 | DMA_NC},
{USBD_EP0RD, DMA_DR | DMA_DW8 | DMA_NC},
{USBD_EP0WR, DMA_DW8 | DMA_NC},
{USBD_EP2WR, DMA_DW8 | DMA_NC},
{USBD_EP3WR, DMA_DW8 | DMA_NC},
{USBD_EP4RD, DMA_DR | DMA_DW8 | DMA_NC},
{USBD_EP5RD, DMA_DR | DMA_DW8 | DMA_NC},
{I2S_DATA, DMA_DW32 | DMA_NC},
{I2S_DATA, DMA_DR | DMA_DW32 | DMA_NC}
};
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++) {
if ((chan = get_dma_chan(i)) != NULL) {
len += sprintf(buf + len, "%2d: %s\n",
i, chan->dev_str);
}
}
if (fpos >= len) {
*start = buf;
*eof = 1;
return 0;
}
*start = buf + fpos;
if ((len -= fpos) > 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] = {
{SD0_XMIT_FIFO, DMA_DS | DMA_DW8}, // coherent
{SD0_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8}, // coherent
{SD1_XMIT_FIFO, DMA_DS | DMA_DW8}, // coherent
{SD1_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8} // 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,
irqreturn_t (*irqhandler)(int, void *, struct pt_regs *),
unsigned long irqflags,
void *irq_dev_id)
{
struct dma_chan *chan;
const struct dma_dev *dev;
int i, ret;
#if defined(CONFIG_SOC_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;
#endif
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 = AU1000_DMA_INT_BASE + i;
chan->irq_dev = irq_dev_id;
if ((ret = request_irq(chan->irq, irqhandler, irqflags,
dev_str, chan->irq_dev))) {
chan->irq = 0;
chan->irq_dev = NULL;
return ret;
}
} else {
chan->irq = 0;
chan->irq_dev = NULL;
}
// fill it in
chan->io = DMA_CHANNEL_BASE + 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("Trying to free DMA%d\n", dmanr);
return;
}
disable_dma(dmanr);
if (chan->irq)
free_irq(chan->irq, chan->irq_dev);
chan->irq = 0;
chan->irq_dev = NULL;
chan->dev_id = -1;
}
EXPORT_SYMBOL(free_au1000_dma);
#endif // AU1000 AU1500 AU1100
|
