1 /*
2 ** linux/amiga/chipram.c
3 **
4 ** Modified 03-May-94 by Geert Uytterhoeven <geert@linux-m68k.org>
5 ** - 64-bit aligned allocations for full AGA compatibility
6 **
7 ** Rewritten 15/9/2000 by Geert to use resource management
8 */
9
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/module.h>
18
19 #include <asm/page.h>
20 #include <asm/amigahw.h>
21
22 unsigned long amiga_chip_size;
23 EXPORT_SYMBOL(amiga_chip_size);
24
25 static struct resource chipram_res = {
26 .name = "Chip RAM", .start = CHIP_PHYSADDR
27 };
28 static unsigned long chipavail;
29
30
amiga_chip_init(void)31 void __init amiga_chip_init(void)
32 {
33 if (!AMIGAHW_PRESENT(CHIP_RAM))
34 return;
35
36 /*
37 * Remove the first 4 pages where PPC exception handlers will be located
38 */
39 amiga_chip_size -= 0x4000;
40 chipram_res.end = amiga_chip_size-1;
41 request_resource(&iomem_resource, &chipram_res);
42
43 chipavail = amiga_chip_size;
44 }
45
46
amiga_chip_alloc(unsigned long size,const char * name)47 void *amiga_chip_alloc(unsigned long size, const char *name)
48 {
49 struct resource *res;
50
51 /* round up */
52 size = PAGE_ALIGN(size);
53
54 #ifdef DEBUG
55 printk("amiga_chip_alloc: allocate %ld bytes\n", size);
56 #endif
57 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
58 if (!res)
59 return NULL;
60 res->name = name;
61
62 if (allocate_resource(&chipram_res, res, size, 0, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0) {
63 kfree(res);
64 return NULL;
65 }
66 chipavail -= size;
67 #ifdef DEBUG
68 printk("amiga_chip_alloc: returning %lx\n", res->start);
69 #endif
70 return (void *)ZTWO_VADDR(res->start);
71 }
72 EXPORT_SYMBOL(amiga_chip_alloc);
73
74
75 /*
76 * Warning:
77 * amiga_chip_alloc_res is meant only for drivers that need to allocate
78 * Chip RAM before kmalloc() is functional. As a consequence, those
79 * drivers must not free that Chip RAM afterwards.
80 */
81
amiga_chip_alloc_res(unsigned long size,struct resource * res)82 void * __init amiga_chip_alloc_res(unsigned long size, struct resource *res)
83 {
84 unsigned long start;
85
86 /* round up */
87 size = PAGE_ALIGN(size);
88 /* dmesg into chipmem prefers memory at the safe end */
89 start = CHIP_PHYSADDR + chipavail - size;
90
91 #ifdef DEBUG
92 printk("amiga_chip_alloc_res: allocate %ld bytes\n", size);
93 #endif
94 if (allocate_resource(&chipram_res, res, size, start, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0) {
95 printk("amiga_chip_alloc_res: first alloc failed!\n");
96 if (allocate_resource(&chipram_res, res, size, 0, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0)
97 return NULL;
98 }
99 chipavail -= size;
100 #ifdef DEBUG
101 printk("amiga_chip_alloc_res: returning %lx\n", res->start);
102 #endif
103 return (void *)ZTWO_VADDR(res->start);
104 }
105
amiga_chip_free(void * ptr)106 void amiga_chip_free(void *ptr)
107 {
108 unsigned long start = ZTWO_PADDR(ptr);
109 struct resource **p, *res;
110 unsigned long size;
111
112 for (p = &chipram_res.child; (res = *p); p = &res->sibling) {
113 if (res->start != start)
114 continue;
115 *p = res->sibling;
116 size = res->end-start;
117 #ifdef DEBUG
118 printk("amiga_chip_free: free %ld bytes at %p\n", size, ptr);
119 #endif
120 chipavail += size;
121 kfree(res);
122 return;
123 }
124 printk("amiga_chip_free: trying to free nonexistent region at %p\n", ptr);
125 }
126 EXPORT_SYMBOL(amiga_chip_free);
127
128
amiga_chip_avail(void)129 unsigned long amiga_chip_avail(void)
130 {
131 #ifdef DEBUG
132 printk("amiga_chip_avail : %ld bytes\n", chipavail);
133 #endif
134 return chipavail;
135 }
136 EXPORT_SYMBOL(amiga_chip_avail);
137
138