xref: /openbmc/linux/sound/isa/gus/gus_dma.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Routines for GF1 DMA control
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <asm/dma.h>
8 #include <linux/slab.h>
9 #include <sound/core.h>
10 #include <sound/gus.h>
11 
12 static void snd_gf1_dma_ack(struct snd_gus_card * gus)
13 {
14 	unsigned long flags;
15 
16 	spin_lock_irqsave(&gus->reg_lock, flags);
17 	snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL, 0x00);
18 	snd_gf1_look8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL);
19 	spin_unlock_irqrestore(&gus->reg_lock, flags);
20 }
21 
22 static void snd_gf1_dma_program(struct snd_gus_card * gus,
23 				unsigned int addr,
24 				unsigned long buf_addr,
25 				unsigned int count,
26 				unsigned int cmd)
27 {
28 	unsigned long flags;
29 	unsigned int address;
30 	unsigned char dma_cmd;
31 	unsigned int address_high;
32 
33 	snd_printdd("dma_transfer: addr=0x%x, buf=0x%lx, count=0x%x\n",
34 		    addr, buf_addr, count);
35 
36 	if (gus->gf1.dma1 > 3) {
37 		if (gus->gf1.enh_mode) {
38 			address = addr >> 1;
39 		} else {
40 			if (addr & 0x1f) {
41 				snd_printd("snd_gf1_dma_transfer: unaligned address (0x%x)?\n", addr);
42 				return;
43 			}
44 			address = (addr & 0x000c0000) | ((addr & 0x0003ffff) >> 1);
45 		}
46 	} else {
47 		address = addr;
48 	}
49 
50 	dma_cmd = SNDRV_GF1_DMA_ENABLE | (unsigned short) cmd;
51 #if 0
52 	dma_cmd |= 0x08;
53 #endif
54 	if (dma_cmd & SNDRV_GF1_DMA_16BIT) {
55 		count++;
56 		count &= ~1;	/* align */
57 	}
58 	if (gus->gf1.dma1 > 3) {
59 		dma_cmd |= SNDRV_GF1_DMA_WIDTH16;
60 		count++;
61 		count &= ~1;	/* align */
62 	}
63 	snd_gf1_dma_ack(gus);
64 	snd_dma_program(gus->gf1.dma1, buf_addr, count, dma_cmd & SNDRV_GF1_DMA_READ ? DMA_MODE_READ : DMA_MODE_WRITE);
65 #if 0
66 	snd_printk(KERN_DEBUG "address = 0x%x, count = 0x%x, dma_cmd = 0x%x\n",
67 		   address << 1, count, dma_cmd);
68 #endif
69 	spin_lock_irqsave(&gus->reg_lock, flags);
70 	if (gus->gf1.enh_mode) {
71 		address_high = ((address >> 16) & 0x000000f0) | (address & 0x0000000f);
72 		snd_gf1_write16(gus, SNDRV_GF1_GW_DRAM_DMA_LOW, (unsigned short) (address >> 4));
73 		snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_HIGH, (unsigned char) address_high);
74 	} else
75 		snd_gf1_write16(gus, SNDRV_GF1_GW_DRAM_DMA_LOW, (unsigned short) (address >> 4));
76 	snd_gf1_write8(gus, SNDRV_GF1_GB_DRAM_DMA_CONTROL, dma_cmd);
77 	spin_unlock_irqrestore(&gus->reg_lock, flags);
78 }
79 
80 static struct snd_gf1_dma_block *snd_gf1_dma_next_block(struct snd_gus_card * gus)
81 {
82 	struct snd_gf1_dma_block *block;
83 
84 	/* PCM block have bigger priority than synthesizer one */
85 	if (gus->gf1.dma_data_pcm) {
86 		block = gus->gf1.dma_data_pcm;
87 		if (gus->gf1.dma_data_pcm_last == block) {
88 			gus->gf1.dma_data_pcm =
89 			gus->gf1.dma_data_pcm_last = NULL;
90 		} else {
91 			gus->gf1.dma_data_pcm = block->next;
92 		}
93 	} else if (gus->gf1.dma_data_synth) {
94 		block = gus->gf1.dma_data_synth;
95 		if (gus->gf1.dma_data_synth_last == block) {
96 			gus->gf1.dma_data_synth =
97 			gus->gf1.dma_data_synth_last = NULL;
98 		} else {
99 			gus->gf1.dma_data_synth = block->next;
100 		}
101 	} else {
102 		block = NULL;
103 	}
104 	if (block) {
105 		gus->gf1.dma_ack = block->ack;
106 		gus->gf1.dma_private_data = block->private_data;
107 	}
108 	return block;
109 }
110 
111 
112 static void snd_gf1_dma_interrupt(struct snd_gus_card * gus)
113 {
114 	struct snd_gf1_dma_block *block;
115 
116 	snd_gf1_dma_ack(gus);
117 	if (gus->gf1.dma_ack)
118 		gus->gf1.dma_ack(gus, gus->gf1.dma_private_data);
119 	spin_lock(&gus->dma_lock);
120 	if (gus->gf1.dma_data_pcm == NULL &&
121 	    gus->gf1.dma_data_synth == NULL) {
122 	    	gus->gf1.dma_ack = NULL;
123 		gus->gf1.dma_flags &= ~SNDRV_GF1_DMA_TRIGGER;
124 		spin_unlock(&gus->dma_lock);
125 		return;
126 	}
127 	block = snd_gf1_dma_next_block(gus);
128 	spin_unlock(&gus->dma_lock);
129 	snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
130 	kfree(block);
131 #if 0
132 	snd_printd(KERN_DEBUG "program dma (IRQ) - "
133 		   "addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
134 		   block->addr, block->buf_addr, block->count, block->cmd);
135 #endif
136 }
137 
138 int snd_gf1_dma_init(struct snd_gus_card * gus)
139 {
140 	mutex_lock(&gus->dma_mutex);
141 	gus->gf1.dma_shared++;
142 	if (gus->gf1.dma_shared > 1) {
143 		mutex_unlock(&gus->dma_mutex);
144 		return 0;
145 	}
146 	gus->gf1.interrupt_handler_dma_write = snd_gf1_dma_interrupt;
147 	gus->gf1.dma_data_pcm =
148 	gus->gf1.dma_data_pcm_last =
149 	gus->gf1.dma_data_synth =
150 	gus->gf1.dma_data_synth_last = NULL;
151 	mutex_unlock(&gus->dma_mutex);
152 	return 0;
153 }
154 
155 int snd_gf1_dma_done(struct snd_gus_card * gus)
156 {
157 	struct snd_gf1_dma_block *block;
158 
159 	mutex_lock(&gus->dma_mutex);
160 	gus->gf1.dma_shared--;
161 	if (!gus->gf1.dma_shared) {
162 		snd_dma_disable(gus->gf1.dma1);
163 		snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_DMA_WRITE);
164 		snd_gf1_dma_ack(gus);
165 		while ((block = gus->gf1.dma_data_pcm)) {
166 			gus->gf1.dma_data_pcm = block->next;
167 			kfree(block);
168 		}
169 		while ((block = gus->gf1.dma_data_synth)) {
170 			gus->gf1.dma_data_synth = block->next;
171 			kfree(block);
172 		}
173 		gus->gf1.dma_data_pcm_last =
174 		gus->gf1.dma_data_synth_last = NULL;
175 	}
176 	mutex_unlock(&gus->dma_mutex);
177 	return 0;
178 }
179 
180 int snd_gf1_dma_transfer_block(struct snd_gus_card * gus,
181 			       struct snd_gf1_dma_block * __block,
182 			       int atomic,
183 			       int synth)
184 {
185 	unsigned long flags;
186 	struct snd_gf1_dma_block *block;
187 
188 	block = kmalloc(sizeof(*block), atomic ? GFP_ATOMIC : GFP_KERNEL);
189 	if (!block)
190 		return -ENOMEM;
191 
192 	*block = *__block;
193 	block->next = NULL;
194 
195 	snd_printdd("addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
196 		    block->addr, (long) block->buffer, block->count,
197 		    block->cmd);
198 
199 	snd_printdd("gus->gf1.dma_data_pcm_last = 0x%lx\n",
200 		    (long)gus->gf1.dma_data_pcm_last);
201 	snd_printdd("gus->gf1.dma_data_pcm = 0x%lx\n",
202 		    (long)gus->gf1.dma_data_pcm);
203 
204 	spin_lock_irqsave(&gus->dma_lock, flags);
205 	if (synth) {
206 		if (gus->gf1.dma_data_synth_last) {
207 			gus->gf1.dma_data_synth_last->next = block;
208 			gus->gf1.dma_data_synth_last = block;
209 		} else {
210 			gus->gf1.dma_data_synth =
211 			gus->gf1.dma_data_synth_last = block;
212 		}
213 	} else {
214 		if (gus->gf1.dma_data_pcm_last) {
215 			gus->gf1.dma_data_pcm_last->next = block;
216 			gus->gf1.dma_data_pcm_last = block;
217 		} else {
218 			gus->gf1.dma_data_pcm =
219 			gus->gf1.dma_data_pcm_last = block;
220 		}
221 	}
222 	if (!(gus->gf1.dma_flags & SNDRV_GF1_DMA_TRIGGER)) {
223 		gus->gf1.dma_flags |= SNDRV_GF1_DMA_TRIGGER;
224 		block = snd_gf1_dma_next_block(gus);
225 		spin_unlock_irqrestore(&gus->dma_lock, flags);
226 		if (block == NULL)
227 			return 0;
228 		snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
229 		kfree(block);
230 		return 0;
231 	}
232 	spin_unlock_irqrestore(&gus->dma_lock, flags);
233 	return 0;
234 }
235