1 /*
2  * arch/sh/kernel/dma.c
3  *
4  * Copyright (C) 2000 Takashi YOSHII
5  *
6  * PC like DMA API for SuperH's DMAC.
7  */
8 
9 #include <linux/config.h>
10 #include <linux/init.h>
11 #include <linux/irq.h>
12 #include <linux/interrupt.h>
13 #include <linux/module.h>
14 
15 #include <asm/signal.h>
16 #include <asm/dma.h>
17 
18 static struct dma_info_t *dma_info[MAX_DMA_CHANNELS];
19 static struct dma_info_t *autoinit_info[SH_MAX_DMA_CHANNELS] = {0};
20 static spinlock_t  dma_spin_lock;
21 
calc_chcr(struct dma_info_t * info)22 static unsigned int calc_chcr(struct dma_info_t *info)
23 {
24 	unsigned int chcr;
25 
26 	chcr = ( info->mode & DMA_MODE_WRITE )? info->mode_write : info->mode_read;
27 	if( info->mode & DMA_AUTOINIT )
28 		chcr |= CHCR_IE;
29 	return chcr;
30 }
31 
ts_shift(unsigned long chcr)32 static __inline__ int ts_shift(unsigned long chcr)
33 {
34 	return ((int[]){3,0,1,2,5,0,0,0})[(chcr>>4)&0x000007];
35 }
36 
dma_tei(int irq,void * dev_id,struct pt_regs * regs)37 static void dma_tei(int irq, void *dev_id, struct pt_regs *regs)
38 {
39 	int chan = irq - DMTE_IRQ[0];
40 	struct dma_info_t *info = autoinit_info[chan];
41 
42 	if( info->mode & DMA_MODE_WRITE )
43 		ctrl_outl(info->mem_addr, SAR[info->chan]);
44 	else
45 		ctrl_outl(info->mem_addr, DAR[info->chan]);
46 
47 	ctrl_outl(info->count>>ts_shift(calc_chcr(info)), DMATCR[info->chan]);
48 	ctrl_outl(ctrl_inl(CHCR[info->chan])&~CHCR_TE, CHCR[info->chan]);
49 }
50 
51 static struct irqaction irq_tei = { dma_tei, SA_INTERRUPT, 0, "dma_tei", NULL, NULL};
52 
setup_dma(unsigned int dmanr,struct dma_info_t * info)53 void setup_dma(unsigned int dmanr, struct dma_info_t *info)
54 {
55 	make_ipr_irq(DMTE_IRQ[info->chan], DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
56 	setup_irq(DMTE_IRQ[info->chan], &irq_tei);
57 	dma_info[dmanr] = info;
58 }
59 
claim_dma_lock(void)60 unsigned long claim_dma_lock(void)
61 {
62 	unsigned long flags;
63 	spin_lock_irqsave(&dma_spin_lock, flags);
64 	return flags;
65 }
66 
release_dma_lock(unsigned long flags)67 void release_dma_lock(unsigned long flags)
68 {
69 	spin_unlock_irqrestore(&dma_spin_lock, flags);
70 }
71 
enable_dma(unsigned int dmanr)72 void enable_dma(unsigned int dmanr)
73 {
74 	struct dma_info_t *info = dma_info[dmanr];
75 	ctrl_outl(calc_chcr(info)|CHCR_DE, CHCR[info->chan]);
76 }
77 
disable_dma(unsigned int dmanr)78 void disable_dma(unsigned int dmanr)
79 {
80 	struct dma_info_t *info = dma_info[dmanr];
81 	ctrl_outl(calc_chcr(info)&~CHCR_DE, CHCR[info->chan]);
82 }
83 
set_dma_mode(unsigned int dmanr,char mode)84 void set_dma_mode(unsigned int dmanr, char mode)
85 {
86 	struct dma_info_t *info = dma_info[dmanr];
87 
88 	info->mode = mode;
89 	set_dma_addr(dmanr, info->mem_addr);
90 	set_dma_count(dmanr, info->count);
91 	autoinit_info[info->chan] = info;
92 }
93 
set_dma_addr(unsigned int dmanr,unsigned int a)94 void set_dma_addr(unsigned int dmanr, unsigned int a)
95 {
96 	struct dma_info_t *info = dma_info[dmanr];
97 	unsigned long sar, dar;
98 
99 	info->mem_addr = a;
100 	sar = (info->mode & DMA_MODE_WRITE)? info->mem_addr: info->dev_addr;
101 	dar = (info->mode & DMA_MODE_WRITE)? info->dev_addr: info->mem_addr;
102 	ctrl_outl(sar, SAR[info->chan]);
103 	ctrl_outl(dar, DAR[info->chan]);
104 }
105 
set_dma_count(unsigned int dmanr,unsigned int count)106 void set_dma_count(unsigned int dmanr, unsigned int count)
107 {
108 	struct dma_info_t *info = dma_info[dmanr];
109 	info->count = count;
110 	ctrl_outl(count>>ts_shift(calc_chcr(info)), DMATCR[info->chan]);
111 }
112 
get_dma_residue(unsigned int dmanr)113 int get_dma_residue(unsigned int dmanr)
114 {
115 	struct dma_info_t *info = dma_info[dmanr];
116 	return ctrl_inl(DMATCR[info->chan])<<ts_shift(calc_chcr(info));
117 }
118 
119 #if defined(__SH4__)
dma_err(int irq,void * dev_id,struct pt_regs * regs)120 static void dma_err(int irq, void *dev_id, struct pt_regs *regs)
121 {
122 	printk(KERN_WARNING "DMAE: DMAOR=%lx\n",ctrl_inl(DMAOR));
123 	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_NMIF, DMAOR);
124 	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_AE, DMAOR);
125 	ctrl_outl(ctrl_inl(DMAOR)|DMAOR_DME, DMAOR);
126 }
127 static struct irqaction irq_err = { dma_err, SA_INTERRUPT, 0, "dma_err", NULL, NULL};
128 #endif
129 
init_dma(void)130 int __init init_dma(void)
131 {
132 #if defined(__SH4__)
133 	make_ipr_irq(DMAE_IRQ, DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
134 	setup_irq(DMAE_IRQ, &irq_err);
135 #endif
136 
137 	ctrl_outl(DMAOR_DME, DMAOR);
138 	return 0;
139 }
140 
exit_dma(void)141 static void __exit exit_dma(void)
142 {
143 #ifdef CONFIG_CPU_SH4
144 	free_irq(DMAE_IRQ);
145 #endif
146 }
147 
148 module_init(init_dma);
149 module_exit(exit_dma);
150 
151 MODULE_LICENSE("GPL");
152 
153 EXPORT_SYMBOL(setup_dma);
154 EXPORT_SYMBOL(claim_dma_lock);
155 EXPORT_SYMBOL(release_dma_lock);
156 EXPORT_SYMBOL(enable_dma);
157 EXPORT_SYMBOL(disable_dma);
158 EXPORT_SYMBOL(set_dma_mode);
159 EXPORT_SYMBOL(set_dma_addr);
160 EXPORT_SYMBOL(set_dma_count);
161 EXPORT_SYMBOL(get_dma_residue);
162 
163