1/*
2 *  Routines for GF1 DMA control
3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 *   This program is free software; you can redistribute it and/or modify
7 *   it under the terms of the GNU General Public License as published by
8 *   the Free Software Foundation; either version 2 of the License, or
9 *   (at your option) any later version.
10 *
11 *   This program is distributed in the hope that it will be useful,
12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *   GNU General Public License for more details.
15 *
16 *   You should have received a copy of the GNU General Public License
17 *   along with this program; if not, write to the Free Software
18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19 *
20 */
21
22#include <asm/dma.h>
23#include <linux/slab.h>
24#include <sound/core.h>
25#include <sound/gus.h>
26
27static void snd_gf1_dma_ack(struct snd_gus_card * gus)
28{
29	unsigned long flags;
30
31	spin_lock_irqsave(&gus->reg_lock, flags);
32	snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL, 0x00);
33	snd_gf1_look8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL);
34	spin_unlock_irqrestore(&gus->reg_lock, flags);
35}
36
37static void snd_gf1_dma_program(struct snd_gus_card * gus,
38				unsigned int addr,
39				unsigned long buf_addr,
40				unsigned int count,
41				unsigned int cmd)
42{
43	unsigned long flags;
44	unsigned int address;
45	unsigned char dma_cmd;
46	unsigned int address_high;
47
48	snd_printdd("dma_transfer: addr=0x%x, buf=0x%lx, count=0x%x\n",
49		    addr, buf_addr, count);
50
51	if (gus->gf1.dma1 > 3) {
52		if (gus->gf1.enh_mode) {
53			address = addr >> 1;
54		} else {
55			if (addr & 0x1f) {
56				snd_printd("snd_gf1_dma_transfer: unaligned address (0x%x)?\n", addr);
57				return;
58			}
59			address = (addr & 0x000c0000) | ((addr & 0x0003ffff) >> 1);
60		}
61	} else {
62		address = addr;
63	}
64
65	dma_cmd = SNDRV_GF1_DMA_ENABLE | (unsigned short) cmd;
66#if 0
67	dma_cmd |= 0x08;
68#endif
69	if (dma_cmd & SNDRV_GF1_DMA_16BIT) {
70		count++;
71		count &= ~1;	/* align */
72	}
73	if (gus->gf1.dma1 > 3) {
74		dma_cmd |= SNDRV_GF1_DMA_WIDTH16;
75		count++;
76		count &= ~1;	/* align */
77	}
78	snd_gf1_dma_ack(gus);
79	snd_dma_program(gus->gf1.dma1, buf_addr, count, dma_cmd & SNDRV_GF1_DMA_READ ? DMA_MODE_READ : DMA_MODE_WRITE);
80#if 0
81	snd_printk(KERN_DEBUG "address = 0x%x, count = 0x%x, dma_cmd = 0x%x\n",
82		   address << 1, count, dma_cmd);
83#endif
84	spin_lock_irqsave(&gus->reg_lock, flags);
85	if (gus->gf1.enh_mode) {
86		address_high = ((address >> 16) & 0x000000f0) | (address & 0x0000000f);
87		snd_gf1_write16(gus, SNDRV_GF1_GW_DRAM_DMA_LOW, (unsigned short) (address >> 4));
88		snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_HIGH, (unsigned char) address_high);
89	} else
90		snd_gf1_write16(gus, SNDRV_GF1_GW_DRAM_DMA_LOW, (unsigned short) (address >> 4));
91	snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL, dma_cmd);
92	spin_unlock_irqrestore(&gus->reg_lock, flags);
93}
94
95static struct snd_gf1_dma_block *snd_gf1_dma_next_block(struct snd_gus_card * gus)
96{
97	struct snd_gf1_dma_block *block;
98
99	/* PCM block have bigger priority than synthesizer one */
100	if (gus->gf1.dma_data_pcm) {
101		block = gus->gf1.dma_data_pcm;
102		if (gus->gf1.dma_data_pcm_last == block) {
103			gus->gf1.dma_data_pcm =
104			gus->gf1.dma_data_pcm_last = NULL;
105		} else {
106			gus->gf1.dma_data_pcm = block->next;
107		}
108	} else if (gus->gf1.dma_data_synth) {
109		block = gus->gf1.dma_data_synth;
110		if (gus->gf1.dma_data_synth_last == block) {
111			gus->gf1.dma_data_synth =
112			gus->gf1.dma_data_synth_last = NULL;
113		} else {
114			gus->gf1.dma_data_synth = block->next;
115		}
116	} else {
117		block = NULL;
118	}
119	if (block) {
120		gus->gf1.dma_ack = block->ack;
121		gus->gf1.dma_private_data = block->private_data;
122	}
123	return block;
124}
125
126
127static void snd_gf1_dma_interrupt(struct snd_gus_card * gus)
128{
129	struct snd_gf1_dma_block *block;
130
131	snd_gf1_dma_ack(gus);
132	if (gus->gf1.dma_ack)
133		gus->gf1.dma_ack(gus, gus->gf1.dma_private_data);
134	spin_lock(&gus->dma_lock);
135	if (gus->gf1.dma_data_pcm == NULL &&
136	    gus->gf1.dma_data_synth == NULL) {
137	    	gus->gf1.dma_ack = NULL;
138		gus->gf1.dma_flags &= ~SNDRV_GF1_DMA_TRIGGER;
139		spin_unlock(&gus->dma_lock);
140		return;
141	}
142	block = snd_gf1_dma_next_block(gus);
143	spin_unlock(&gus->dma_lock);
144	snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
145	kfree(block);
146#if 0
147	snd_printd(KERN_DEBUG "program dma (IRQ) - "
148		   "addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
149		   block->addr, block->buf_addr, block->count, block->cmd);
150#endif
151}
152
153int snd_gf1_dma_init(struct snd_gus_card * gus)
154{
155	mutex_lock(&gus->dma_mutex);
156	gus->gf1.dma_shared++;
157	if (gus->gf1.dma_shared > 1) {
158		mutex_unlock(&gus->dma_mutex);
159		return 0;
160	}
161	gus->gf1.interrupt_handler_dma_write = snd_gf1_dma_interrupt;
162	gus->gf1.dma_data_pcm =
163	gus->gf1.dma_data_pcm_last =
164	gus->gf1.dma_data_synth =
165	gus->gf1.dma_data_synth_last = NULL;
166	mutex_unlock(&gus->dma_mutex);
167	return 0;
168}
169
170int snd_gf1_dma_done(struct snd_gus_card * gus)
171{
172	struct snd_gf1_dma_block *block;
173
174	mutex_lock(&gus->dma_mutex);
175	gus->gf1.dma_shared--;
176	if (!gus->gf1.dma_shared) {
177		snd_dma_disable(gus->gf1.dma1);
178		snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_DMA_WRITE);
179		snd_gf1_dma_ack(gus);
180		while ((block = gus->gf1.dma_data_pcm)) {
181			gus->gf1.dma_data_pcm = block->next;
182			kfree(block);
183		}
184		while ((block = gus->gf1.dma_data_synth)) {
185			gus->gf1.dma_data_synth = block->next;
186			kfree(block);
187		}
188		gus->gf1.dma_data_pcm_last =
189		gus->gf1.dma_data_synth_last = NULL;
190	}
191	mutex_unlock(&gus->dma_mutex);
192	return 0;
193}
194
195int snd_gf1_dma_transfer_block(struct snd_gus_card * gus,
196			       struct snd_gf1_dma_block * __block,
197			       int atomic,
198			       int synth)
199{
200	unsigned long flags;
201	struct snd_gf1_dma_block *block;
202
203	block = kmalloc(sizeof(*block), atomic ? GFP_ATOMIC : GFP_KERNEL);
204	if (block == NULL) {
205		snd_printk(KERN_ERR "gf1: DMA transfer failure; not enough memory\n");
206		return -ENOMEM;
207	}
208	*block = *__block;
209	block->next = NULL;
210
211	snd_printdd("addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
212		    block->addr, (long) block->buffer, block->count,
213		    block->cmd);
214
215	snd_printdd("gus->gf1.dma_data_pcm_last = 0x%lx\n",
216		    (long)gus->gf1.dma_data_pcm_last);
217	snd_printdd("gus->gf1.dma_data_pcm = 0x%lx\n",
218		    (long)gus->gf1.dma_data_pcm);
219
220	spin_lock_irqsave(&gus->dma_lock, flags);
221	if (synth) {
222		if (gus->gf1.dma_data_synth_last) {
223			gus->gf1.dma_data_synth_last->next = block;
224			gus->gf1.dma_data_synth_last = block;
225		} else {
226			gus->gf1.dma_data_synth =
227			gus->gf1.dma_data_synth_last = block;
228		}
229	} else {
230		if (gus->gf1.dma_data_pcm_last) {
231			gus->gf1.dma_data_pcm_last->next = block;
232			gus->gf1.dma_data_pcm_last = block;
233		} else {
234			gus->gf1.dma_data_pcm =
235			gus->gf1.dma_data_pcm_last = block;
236		}
237	}
238	if (!(gus->gf1.dma_flags & SNDRV_GF1_DMA_TRIGGER)) {
239		gus->gf1.dma_flags |= SNDRV_GF1_DMA_TRIGGER;
240		block = snd_gf1_dma_next_block(gus);
241		spin_unlock_irqrestore(&gus->dma_lock, flags);
242		if (block == NULL)
243			return 0;
244		snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
245		kfree(block);
246		return 0;
247	}
248	spin_unlock_irqrestore(&gus->dma_lock, flags);
249	return 0;
250}
251