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
12static 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
22static 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
80static 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
112static 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	if (!block)
130		return;
131	snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
132	kfree(block);
133#if 0
134	snd_printd(KERN_DEBUG "program dma (IRQ) - "
135		   "addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
136		   block->addr, block->buf_addr, block->count, block->cmd);
137#endif
138}
139
140int snd_gf1_dma_init(struct snd_gus_card * gus)
141{
142	mutex_lock(&gus->dma_mutex);
143	gus->gf1.dma_shared++;
144	if (gus->gf1.dma_shared > 1) {
145		mutex_unlock(&gus->dma_mutex);
146		return 0;
147	}
148	gus->gf1.interrupt_handler_dma_write = snd_gf1_dma_interrupt;
149	gus->gf1.dma_data_pcm =
150	gus->gf1.dma_data_pcm_last =
151	gus->gf1.dma_data_synth =
152	gus->gf1.dma_data_synth_last = NULL;
153	mutex_unlock(&gus->dma_mutex);
154	return 0;
155}
156
157int snd_gf1_dma_done(struct snd_gus_card * gus)
158{
159	struct snd_gf1_dma_block *block;
160
161	mutex_lock(&gus->dma_mutex);
162	gus->gf1.dma_shared--;
163	if (!gus->gf1.dma_shared) {
164		snd_dma_disable(gus->gf1.dma1);
165		snd_gf1_set_default_handlers(gus, SNDRV_GF1_HANDLER_DMA_WRITE);
166		snd_gf1_dma_ack(gus);
167		while ((block = gus->gf1.dma_data_pcm)) {
168			gus->gf1.dma_data_pcm = block->next;
169			kfree(block);
170		}
171		while ((block = gus->gf1.dma_data_synth)) {
172			gus->gf1.dma_data_synth = block->next;
173			kfree(block);
174		}
175		gus->gf1.dma_data_pcm_last =
176		gus->gf1.dma_data_synth_last = NULL;
177	}
178	mutex_unlock(&gus->dma_mutex);
179	return 0;
180}
181
182int snd_gf1_dma_transfer_block(struct snd_gus_card * gus,
183			       struct snd_gf1_dma_block * __block,
184			       int atomic,
185			       int synth)
186{
187	unsigned long flags;
188	struct snd_gf1_dma_block *block;
189
190	block = kmalloc(sizeof(*block), atomic ? GFP_ATOMIC : GFP_KERNEL);
191	if (!block)
192		return -ENOMEM;
193
194	*block = *__block;
195	block->next = NULL;
196
197	snd_printdd("addr = 0x%x, buffer = 0x%lx, count = 0x%x, cmd = 0x%x\n",
198		    block->addr, (long) block->buffer, block->count,
199		    block->cmd);
200
201	snd_printdd("gus->gf1.dma_data_pcm_last = 0x%lx\n",
202		    (long)gus->gf1.dma_data_pcm_last);
203	snd_printdd("gus->gf1.dma_data_pcm = 0x%lx\n",
204		    (long)gus->gf1.dma_data_pcm);
205
206	spin_lock_irqsave(&gus->dma_lock, flags);
207	if (synth) {
208		if (gus->gf1.dma_data_synth_last) {
209			gus->gf1.dma_data_synth_last->next = block;
210			gus->gf1.dma_data_synth_last = block;
211		} else {
212			gus->gf1.dma_data_synth =
213			gus->gf1.dma_data_synth_last = block;
214		}
215	} else {
216		if (gus->gf1.dma_data_pcm_last) {
217			gus->gf1.dma_data_pcm_last->next = block;
218			gus->gf1.dma_data_pcm_last = block;
219		} else {
220			gus->gf1.dma_data_pcm =
221			gus->gf1.dma_data_pcm_last = block;
222		}
223	}
224	if (!(gus->gf1.dma_flags & SNDRV_GF1_DMA_TRIGGER)) {
225		gus->gf1.dma_flags |= SNDRV_GF1_DMA_TRIGGER;
226		block = snd_gf1_dma_next_block(gus);
227		spin_unlock_irqrestore(&gus->dma_lock, flags);
228		if (block == NULL)
229			return 0;
230		snd_gf1_dma_program(gus, block->addr, block->buf_addr, block->count, (unsigned short) block->cmd);
231		kfree(block);
232		return 0;
233	}
234	spin_unlock_irqrestore(&gus->dma_lock, flags);
235	return 0;
236}
237