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authorIngo Molnar <mingo@elte.hu>2008-10-12 09:05:39 -0400
committerIngo Molnar <mingo@elte.hu>2008-10-12 09:05:39 -0400
commita9b9e81c915e4a57ac3b21d1a7fa7ff184639780 (patch)
tree98304395fbb5b9c74fca35b196cd414c1949f280 /arch/mips/alchemy/common/dma.c
parenta8b71a2810386a5ac8f43d2095fe3355f0d8db37 (diff)
parentfd048088306656824958e7783ffcee27e241b361 (diff)
Merge branch 'linus' into x86/memory-corruption-check
Diffstat (limited to 'arch/mips/alchemy/common/dma.c')
-rw-r--r--arch/mips/alchemy/common/dma.c238
1 files changed, 238 insertions, 0 deletions
diff --git a/arch/mips/alchemy/common/dma.c b/arch/mips/alchemy/common/dma.c
new file mode 100644
index 000000000000..d6fbda232e6a
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1/*
2 *
3 * BRIEF MODULE DESCRIPTION
4 * A DMA channel allocator for Au1x00. API is modeled loosely off of
5 * linux/kernel/dma.c.
6 *
7 * Copyright 2000, 2008 MontaVista Software Inc.
8 * Author: MontaVista Software, Inc. <source@mvista.com>
9 * Copyright (C) 2005 Ralf Baechle (ralf@linux-mips.org)
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the
13 * Free Software Foundation; either version 2 of the License, or (at your
14 * option) any later version.
15 *
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
19 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
22 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
23 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * You should have received a copy of the GNU General Public License along
28 * with this program; if not, write to the Free Software Foundation, Inc.,
29 * 675 Mass Ave, Cambridge, MA 02139, USA.
30 *
31 */
32#include <linux/module.h>
33#include <linux/kernel.h>
34#include <linux/errno.h>
35#include <linux/spinlock.h>
36#include <linux/interrupt.h>
37
38#include <asm/mach-au1x00/au1000.h>
39#include <asm/mach-au1x00/au1000_dma.h>
40
41#if defined(CONFIG_SOC_AU1000) || defined(CONFIG_SOC_AU1500) || \
42 defined(CONFIG_SOC_AU1100)
43/*
44 * A note on resource allocation:
45 *
46 * All drivers needing DMA channels, should allocate and release them
47 * through the public routines `request_dma()' and `free_dma()'.
48 *
49 * In order to avoid problems, all processes should allocate resources in
50 * the same sequence and release them in the reverse order.
51 *
52 * So, when allocating DMAs and IRQs, first allocate the DMA, then the IRQ.
53 * When releasing them, first release the IRQ, then release the DMA. The
54 * main reason for this order is that, if you are requesting the DMA buffer
55 * done interrupt, you won't know the irq number until the DMA channel is
56 * returned from request_dma.
57 */
58
59DEFINE_SPINLOCK(au1000_dma_spin_lock);
60
61struct dma_chan au1000_dma_table[NUM_AU1000_DMA_CHANNELS] = {
62 {.dev_id = -1,},
63 {.dev_id = -1,},
64 {.dev_id = -1,},
65 {.dev_id = -1,},
66 {.dev_id = -1,},
67 {.dev_id = -1,},
68 {.dev_id = -1,},
69 {.dev_id = -1,}
70};
71EXPORT_SYMBOL(au1000_dma_table);
72
73/* Device FIFO addresses and default DMA modes */
74static const struct dma_dev {
75 unsigned int fifo_addr;
76 unsigned int dma_mode;
77} dma_dev_table[DMA_NUM_DEV] = {
78 {UART0_ADDR + UART_TX, 0},
79 {UART0_ADDR + UART_RX, 0},
80 {0, 0},
81 {0, 0},
82 {AC97C_DATA, DMA_DW16 }, /* coherent */
83 {AC97C_DATA, DMA_DR | DMA_DW16 }, /* coherent */
84 {UART3_ADDR + UART_TX, DMA_DW8 | DMA_NC},
85 {UART3_ADDR + UART_RX, DMA_DR | DMA_DW8 | DMA_NC},
86 {USBD_EP0RD, DMA_DR | DMA_DW8 | DMA_NC},
87 {USBD_EP0WR, DMA_DW8 | DMA_NC},
88 {USBD_EP2WR, DMA_DW8 | DMA_NC},
89 {USBD_EP3WR, DMA_DW8 | DMA_NC},
90 {USBD_EP4RD, DMA_DR | DMA_DW8 | DMA_NC},
91 {USBD_EP5RD, DMA_DR | DMA_DW8 | DMA_NC},
92 {I2S_DATA, DMA_DW32 | DMA_NC},
93 {I2S_DATA, DMA_DR | DMA_DW32 | DMA_NC}
94};
95
96int au1000_dma_read_proc(char *buf, char **start, off_t fpos,
97 int length, int *eof, void *data)
98{
99 int i, len = 0;
100 struct dma_chan *chan;
101
102 for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++) {
103 chan = get_dma_chan(i);
104 if (chan != NULL)
105 len += sprintf(buf + len, "%2d: %s\n",
106 i, chan->dev_str);
107 }
108
109 if (fpos >= len) {
110 *start = buf;
111 *eof = 1;
112 return 0;
113 }
114 *start = buf + fpos;
115 len -= fpos;
116 if (len > length)
117 return length;
118 *eof = 1;
119 return len;
120}
121
122/* Device FIFO addresses and default DMA modes - 2nd bank */
123static const struct dma_dev dma_dev_table_bank2[DMA_NUM_DEV_BANK2] = {
124 { SD0_XMIT_FIFO, DMA_DS | DMA_DW8 }, /* coherent */
125 { SD0_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8 }, /* coherent */
126 { SD1_XMIT_FIFO, DMA_DS | DMA_DW8 }, /* coherent */
127 { SD1_RECV_FIFO, DMA_DS | DMA_DR | DMA_DW8 } /* coherent */
128};
129
130void dump_au1000_dma_channel(unsigned int dmanr)
131{
132 struct dma_chan *chan;
133
134 if (dmanr >= NUM_AU1000_DMA_CHANNELS)
135 return;
136 chan = &au1000_dma_table[dmanr];
137
138 printk(KERN_INFO "Au1000 DMA%d Register Dump:\n", dmanr);
139 printk(KERN_INFO " mode = 0x%08x\n",
140 au_readl(chan->io + DMA_MODE_SET));
141 printk(KERN_INFO " addr = 0x%08x\n",
142 au_readl(chan->io + DMA_PERIPHERAL_ADDR));
143 printk(KERN_INFO " start0 = 0x%08x\n",
144 au_readl(chan->io + DMA_BUFFER0_START));
145 printk(KERN_INFO " start1 = 0x%08x\n",
146 au_readl(chan->io + DMA_BUFFER1_START));
147 printk(KERN_INFO " count0 = 0x%08x\n",
148 au_readl(chan->io + DMA_BUFFER0_COUNT));
149 printk(KERN_INFO " count1 = 0x%08x\n",
150 au_readl(chan->io + DMA_BUFFER1_COUNT));
151}
152
153/*
154 * Finds a free channel, and binds the requested device to it.
155 * Returns the allocated channel number, or negative on error.
156 * Requests the DMA done IRQ if irqhandler != NULL.
157 */
158int request_au1000_dma(int dev_id, const char *dev_str,
159 irq_handler_t irqhandler,
160 unsigned long irqflags,
161 void *irq_dev_id)
162{
163 struct dma_chan *chan;
164 const struct dma_dev *dev;
165 int i, ret;
166
167#if defined(CONFIG_SOC_AU1100)
168 if (dev_id < 0 || dev_id >= (DMA_NUM_DEV + DMA_NUM_DEV_BANK2))
169 return -EINVAL;
170#else
171 if (dev_id < 0 || dev_id >= DMA_NUM_DEV)
172 return -EINVAL;
173#endif
174
175 for (i = 0; i < NUM_AU1000_DMA_CHANNELS; i++)
176 if (au1000_dma_table[i].dev_id < 0)
177 break;
178
179 if (i == NUM_AU1000_DMA_CHANNELS)
180 return -ENODEV;
181
182 chan = &au1000_dma_table[i];
183
184 if (dev_id >= DMA_NUM_DEV) {
185 dev_id -= DMA_NUM_DEV;
186 dev = &dma_dev_table_bank2[dev_id];
187 } else
188 dev = &dma_dev_table[dev_id];
189
190 if (irqhandler) {
191 chan->irq = AU1000_DMA_INT_BASE + i;
192 chan->irq_dev = irq_dev_id;
193 ret = request_irq(chan->irq, irqhandler, irqflags, dev_str,
194 chan->irq_dev);
195 if (ret) {
196 chan->irq = 0;
197 chan->irq_dev = NULL;
198 return ret;
199 }
200 } else {
201 chan->irq = 0;
202 chan->irq_dev = NULL;
203 }
204
205 /* fill it in */
206 chan->io = DMA_CHANNEL_BASE + i * DMA_CHANNEL_LEN;
207 chan->dev_id = dev_id;
208 chan->dev_str = dev_str;
209 chan->fifo_addr = dev->fifo_addr;
210 chan->mode = dev->dma_mode;
211
212 /* initialize the channel before returning */
213 init_dma(i);
214
215 return i;
216}
217EXPORT_SYMBOL(request_au1000_dma);
218
219void free_au1000_dma(unsigned int dmanr)
220{
221 struct dma_chan *chan = get_dma_chan(dmanr);
222
223 if (!chan) {
224 printk(KERN_ERR "Error trying to free DMA%d\n", dmanr);
225 return;
226 }
227
228 disable_dma(dmanr);
229 if (chan->irq)
230 free_irq(chan->irq, chan->irq_dev);
231
232 chan->irq = 0;
233 chan->irq_dev = NULL;
234 chan->dev_id = -1;
235}
236EXPORT_SYMBOL(free_au1000_dma);
237
238#endif /* AU1000 AU1500 AU1100 */