1 /* dvma.c:  Routines that are used to access DMA on the Sparc SBus.
2  *
3  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
4  */
5 
6 #include <linux/config.h>
7 #include <linux/string.h>
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
10 #include <linux/init.h>
11 #include <linux/delay.h>
12 
13 #include <asm/oplib.h>
14 #include <asm/io.h>
15 #include <asm/dma.h>
16 #include <asm/sbus.h>
17 
18 struct sbus_dma *dma_chain;
19 
20 /* Print out the current values in the DMA control registers */
dump_dma_regs(unsigned long dregs)21 static inline void dump_dma_regs(unsigned long dregs)
22 {
23 	printk("DMA CONTROL<%08x> ADDR<%08x> CNT<%08x> TEST<%08x>\n",
24 	       sbus_readl(dregs + DMA_CSR), sbus_readl(dregs + DMA_ADDR),
25 	       sbus_readl(dregs + DMA_COUNT), sbus_readl(dregs + DMA_TEST));
26 }
27 
init_one_dvma(struct sbus_dma * dma,int num_dma)28 void __init init_one_dvma(struct sbus_dma *dma, int num_dma)
29 {
30 	printk("dma%d: ", num_dma);
31 
32 	dma->next = 0;
33 	dma->running = 0;      /* No transfers going on as of yet */
34 	dma->allocated = 0;    /* No one has allocated us yet */
35 	switch(sbus_readl(dma->regs + DMA_CSR)&DMA_DEVICE_ID) {
36 	case DMA_VERS0:
37 		dma->revision = dvmarev0;
38 		printk("Revision 0 ");
39 		break;
40 	case DMA_ESCV1:
41 		dma->revision = dvmaesc1;
42 		printk("ESC Revision 1 ");
43 		break;
44 	case DMA_VERS1:
45 		dma->revision = dvmarev1;
46 		printk("Revision 1 ");
47 		break;
48 	case DMA_VERS2:
49 		dma->revision = dvmarev2;
50 		printk("Revision 2 ");
51 		break;
52 	case DMA_VERHME:
53 		dma->revision = dvmahme;
54 		printk("HME DVMA gate array ");
55 		break;
56 	case DMA_VERSPLUS:
57 		dma->revision = dvmarevplus;
58 		printk("Revision 1 PLUS ");
59 		break;
60 	default:
61 		printk("unknown dma version %08x",
62 		       sbus_readl(dma->regs + DMA_CSR) & DMA_DEVICE_ID);
63 		dma->allocated = 1;
64 		break;
65 	}
66 	printk("\n");
67 #if 0 /* Clutters up the screen */
68 	dump_dma_regs(dma->regs);
69 #endif
70 }
71 
72 /* Probe this SBus DMA module(s) */
dvma_init(struct sbus_bus * sbus)73 void __init dvma_init(struct sbus_bus *sbus)
74 {
75 	struct sbus_dev *this_dev;
76 	struct sbus_dma *dma;
77 	struct sbus_dma *dchain;
78 	static int num_dma = 0;
79 
80 	for_each_sbusdev(this_dev, sbus) {
81 		char *name = this_dev->prom_name;
82 		int hme = 0;
83 
84 		if(!strcmp(name, "SUNW,fas"))
85 			hme = 1;
86 		else if(strcmp(name, "dma") &&
87 			strcmp(name, "ledma") &&
88 			strcmp(name, "espdma"))
89 			continue;
90 
91 		/* Found one... */
92 		dma = kmalloc(sizeof(struct sbus_dma), GFP_ATOMIC);
93 
94 		dma->sdev = this_dev;
95 
96 		/* Put at end of dma chain */
97 		dchain = dma_chain;
98 		if(dchain) {
99 			while(dchain->next)
100 				dchain = dchain->next;
101 			dchain->next = dma;
102 		} else {
103 			/* We're the first in line */
104 			dma_chain = dma;
105 		}
106 
107 		dma->regs = sbus_ioremap(&dma->sdev->resource[0], 0,
108 					 dma->sdev->resource[0].end - dma->sdev->resource[0].start + 1,
109 					 "dma");
110 
111 		dma->node = dma->sdev->prom_node;
112 
113 		init_one_dvma(dma, num_dma++);
114 	}
115 }
116 
117 #ifdef CONFIG_SUN4
118 
119 #include <asm/sun4paddr.h>
120 
sun4_dvma_init(void)121 void __init sun4_dvma_init(void)
122 {
123 	struct sbus_dma *dma;
124 	struct sbus_dma *dchain;
125 	struct resource r;
126 
127 	if(sun4_dma_physaddr) {
128 		dma = kmalloc(sizeof(struct sbus_dma), GFP_ATOMIC);
129 
130 		/* No SBUS */
131 		dma->sdev = NULL;
132 
133 		/* Only one DMA device */
134 		dma_chain = dma;
135 
136 		memset(&r, 0, sizeof(r));
137 		r.start = sun4_dma_physaddr;
138 		dma->regs = sbus_ioremap(&r, 0, PAGE_SIZE, "dma");
139 
140 		/* No prom node */
141 		dma->node = 0x0;
142 
143 		init_one_dvma(dma, 0);
144 	} else {
145 	  	dma_chain = NULL;
146 	}
147 }
148 
149 #endif
150