1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | ** linux/amiga/chipram.c |
4 | ** |
5 | ** Modified 03-May-94 by Geert Uytterhoeven <geert@linux-m68k.org> |
6 | ** - 64-bit aligned allocations for full AGA compatibility |
7 | ** |
8 | ** Rewritten 15/9/2000 by Geert to use resource management |
9 | */ |
10 | |
11 | #include <linux/types.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/mm.h> |
14 | #include <linux/init.h> |
15 | #include <linux/ioport.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/string.h> |
18 | #include <linux/module.h> |
19 | |
20 | #include <asm/atomic.h> |
21 | #include <asm/page.h> |
22 | #include <asm/amigahw.h> |
23 | |
24 | unsigned long amiga_chip_size; |
25 | EXPORT_SYMBOL(amiga_chip_size); |
26 | |
27 | static struct resource chipram_res = { |
28 | .name = "Chip RAM" , .start = CHIP_PHYSADDR |
29 | }; |
30 | static atomic_t chipavail; |
31 | |
32 | |
33 | void __init amiga_chip_init(void) |
34 | { |
35 | if (!AMIGAHW_PRESENT(CHIP_RAM)) |
36 | return; |
37 | |
38 | chipram_res.end = CHIP_PHYSADDR + amiga_chip_size - 1; |
39 | request_resource(root: &iomem_resource, new: &chipram_res); |
40 | |
41 | atomic_set(v: &chipavail, i: amiga_chip_size); |
42 | } |
43 | |
44 | |
45 | void *amiga_chip_alloc(unsigned long size, const char *name) |
46 | { |
47 | struct resource *res; |
48 | void *p; |
49 | |
50 | res = kzalloc(size: sizeof(struct resource), GFP_KERNEL); |
51 | if (!res) |
52 | return NULL; |
53 | |
54 | res->name = name; |
55 | p = amiga_chip_alloc_res(size, res); |
56 | if (!p) { |
57 | kfree(objp: res); |
58 | return NULL; |
59 | } |
60 | |
61 | return p; |
62 | } |
63 | EXPORT_SYMBOL(amiga_chip_alloc); |
64 | |
65 | |
66 | /* |
67 | * Warning: |
68 | * amiga_chip_alloc_res is meant only for drivers that need to |
69 | * allocate Chip RAM before kmalloc() is functional. As a consequence, |
70 | * those drivers must not free that Chip RAM afterwards. |
71 | */ |
72 | |
73 | void *amiga_chip_alloc_res(unsigned long size, struct resource *res) |
74 | { |
75 | int error; |
76 | |
77 | /* round up */ |
78 | size = PAGE_ALIGN(size); |
79 | |
80 | pr_debug("amiga_chip_alloc_res: allocate %lu bytes\n" , size); |
81 | error = allocate_resource(root: &chipram_res, new: res, size, min: 0, UINT_MAX, |
82 | PAGE_SIZE, NULL, NULL); |
83 | if (error < 0) { |
84 | pr_err("amiga_chip_alloc_res: allocate_resource() failed %d!\n" , |
85 | error); |
86 | return NULL; |
87 | } |
88 | |
89 | atomic_sub(i: size, v: &chipavail); |
90 | pr_debug("amiga_chip_alloc_res: returning %pR\n" , res); |
91 | return ZTWO_VADDR(res->start); |
92 | } |
93 | |
94 | void amiga_chip_free(void *ptr) |
95 | { |
96 | unsigned long start = ZTWO_PADDR(ptr); |
97 | struct resource *res; |
98 | unsigned long size; |
99 | |
100 | res = lookup_resource(root: &chipram_res, start); |
101 | if (!res) { |
102 | pr_err("amiga_chip_free: trying to free nonexistent region at " |
103 | "%p\n" , ptr); |
104 | return; |
105 | } |
106 | |
107 | size = resource_size(res); |
108 | pr_debug("amiga_chip_free: free %lu bytes at %p\n" , size, ptr); |
109 | atomic_add(i: size, v: &chipavail); |
110 | release_resource(new: res); |
111 | kfree(objp: res); |
112 | } |
113 | EXPORT_SYMBOL(amiga_chip_free); |
114 | |
115 | |
116 | unsigned long amiga_chip_avail(void) |
117 | { |
118 | unsigned long n = atomic_read(v: &chipavail); |
119 | |
120 | pr_debug("amiga_chip_avail : %lu bytes\n" , n); |
121 | return n; |
122 | } |
123 | EXPORT_SYMBOL(amiga_chip_avail); |
124 | |
125 | |