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/atomic.h>
20 #include <asm/page.h>
21 #include <asm/amigahw.h>
22
23 unsigned long amiga_chip_size;
24 EXPORT_SYMBOL(amiga_chip_size);
25
26 static struct resource chipram_res = {
27 .name = "Chip RAM", .start = CHIP_PHYSADDR
28 };
29 static atomic_t chipavail;
30
31
amiga_chip_init(void)32 void __init amiga_chip_init(void)
33 {
34 if (!AMIGAHW_PRESENT(CHIP_RAM))
35 return;
36
37 chipram_res.end = CHIP_PHYSADDR + amiga_chip_size - 1;
38 request_resource(&iomem_resource, &chipram_res);
39
40 atomic_set(&chipavail, amiga_chip_size);
41 }
42
43
amiga_chip_alloc(unsigned long size,const char * name)44 void *amiga_chip_alloc(unsigned long size, const char *name)
45 {
46 struct resource *res;
47 void *p;
48
49 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
50 if (!res)
51 return NULL;
52
53 res->name = name;
54 p = amiga_chip_alloc_res(size, res);
55 if (!p) {
56 kfree(res);
57 return NULL;
58 }
59
60 return p;
61 }
62 EXPORT_SYMBOL(amiga_chip_alloc);
63
64
65 /*
66 * Warning:
67 * amiga_chip_alloc_res is meant only for drivers that need to
68 * allocate Chip RAM before kmalloc() is functional. As a consequence,
69 * those drivers must not free that Chip RAM afterwards.
70 */
71
amiga_chip_alloc_res(unsigned long size,struct resource * res)72 void *amiga_chip_alloc_res(unsigned long size, struct resource *res)
73 {
74 int error;
75
76 /* round up */
77 size = PAGE_ALIGN(size);
78
79 pr_debug("amiga_chip_alloc_res: allocate %lu bytes\n", size);
80 error = allocate_resource(&chipram_res, res, size, 0, UINT_MAX,
81 PAGE_SIZE, NULL, NULL);
82 if (error < 0) {
83 pr_err("amiga_chip_alloc_res: allocate_resource() failed %d!\n",
84 error);
85 return NULL;
86 }
87
88 atomic_sub(size, &chipavail);
89 pr_debug("amiga_chip_alloc_res: returning %pR\n", res);
90 return (void *)ZTWO_VADDR(res->start);
91 }
92
amiga_chip_free(void * ptr)93 void amiga_chip_free(void *ptr)
94 {
95 unsigned long start = ZTWO_PADDR(ptr);
96 struct resource *res;
97 unsigned long size;
98
99 res = lookup_resource(&chipram_res, start);
100 if (!res) {
101 pr_err("amiga_chip_free: trying to free nonexistent region at "
102 "%p\n", ptr);
103 return;
104 }
105
106 size = resource_size(res);
107 pr_debug("amiga_chip_free: free %lu bytes at %p\n", size, ptr);
108 atomic_add(size, &chipavail);
109 release_resource(res);
110 kfree(res);
111 }
112 EXPORT_SYMBOL(amiga_chip_free);
113
114
amiga_chip_avail(void)115 unsigned long amiga_chip_avail(void)
116 {
117 unsigned long n = atomic_read(&chipavail);
118
119 pr_debug("amiga_chip_avail : %lu bytes\n", n);
120 return n;
121 }
122 EXPORT_SYMBOL(amiga_chip_avail);
123
124