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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Michael Schmitz217bbd82010-11-01 19:54:00 +01002 * Functions for ST-RAM allocations
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * Copyright 1994-97 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive
8 * for more details.
9 */
10
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/types.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/kdev_t.h>
15#include <linux/major.h>
16#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/slab.h>
18#include <linux/vmalloc.h>
19#include <linux/pagemap.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/bootmem.h>
21#include <linux/mount.h>
22#include <linux/blkdev.h>
Adrian Bunka3b20042008-02-04 22:30:26 -080023#include <linux/module.h>
Geert Uytterhoeven9aa59ca2014-08-14 09:25:38 +020024#include <linux/ioport.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
26#include <asm/setup.h>
27#include <asm/machdep.h>
28#include <asm/page.h>
29#include <asm/pgtable.h>
30#include <asm/atarihw.h>
31#include <asm/atari_stram.h>
32#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Hugh Dickinsf9c98d02005-10-29 18:16:10 -070035/*
Michael Schmitz217bbd82010-11-01 19:54:00 +010036 * The ST-RAM allocator allocates memory from a pool of reserved ST-RAM of
37 * configurable size, set aside on ST-RAM init.
38 * As long as this pool is not exhausted, allocation of real ST-RAM can be
39 * guaranteed.
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 */
41
Linus Torvalds1da177e2005-04-16 15:20:36 -070042/* set if kernel is in ST-RAM */
43static int kernel_in_stram;
44
Michael Schmitz217bbd82010-11-01 19:54:00 +010045static struct resource stram_pool = {
46 .name = "ST-RAM Pool"
47};
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Michael Schmitz217bbd82010-11-01 19:54:00 +010049static unsigned long pool_size = 1024*1024;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Michael Schmitzfded3322014-03-31 21:06:05 +130051static unsigned long stram_virt_offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Michael Schmitz217bbd82010-11-01 19:54:00 +010053static int __init atari_stram_setup(char *arg)
54{
55 if (!MACH_IS_ATARI)
56 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Michael Schmitz217bbd82010-11-01 19:54:00 +010058 pool_size = memparse(arg, NULL);
59 return 0;
60}
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Michael Schmitz217bbd82010-11-01 19:54:00 +010062early_param("stram_pool", atari_stram_setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65/*
66 * This init function is called very early by atari/config.c
67 * It initializes some internal variables needed for stram_alloc()
68 */
69void __init atari_stram_init(void)
70{
71 int i;
72
Michael Schmitz217bbd82010-11-01 19:54:00 +010073 /*
74 * determine whether kernel code resides in ST-RAM
75 * (then ST-RAM is the first memory block at virtual 0x0)
76 */
Michael Schmitzfded3322014-03-31 21:06:05 +130077 kernel_in_stram = (m68k_memory[0].addr == 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
Michael Schmitz217bbd82010-11-01 19:54:00 +010079 for (i = 0; i < m68k_num_memory; ++i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 if (m68k_memory[i].addr == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 return;
82 }
83 }
Michael Schmitz217bbd82010-11-01 19:54:00 +010084
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 /* Should never come here! (There is always ST-Ram!) */
Michael Schmitz217bbd82010-11-01 19:54:00 +010086 panic("atari_stram_init: no ST-RAM found!");
Linus Torvalds1da177e2005-04-16 15:20:36 -070087}
88
89
90/*
91 * This function is called from setup_arch() to reserve the pages needed for
Michael Schmitzfded3322014-03-31 21:06:05 +130092 * ST-RAM management, if the kernel resides in ST-RAM.
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 */
94void __init atari_stram_reserve_pages(void *start_mem)
95{
Michael Schmitzfded3322014-03-31 21:06:05 +130096 if (kernel_in_stram) {
97 pr_debug("atari_stram pool: kernel in ST-RAM, using alloc_bootmem!\n");
98 stram_pool.start = (resource_size_t)alloc_bootmem_low_pages(pool_size);
99 stram_pool.end = stram_pool.start + pool_size - 1;
100 request_resource(&iomem_resource, &stram_pool);
101 stram_virt_offset = 0;
102 pr_debug("atari_stram pool: size = %lu bytes, resource = %pR\n",
103 pool_size, &stram_pool);
104 pr_debug("atari_stram pool: stram_virt_offset = %lx\n",
105 stram_virt_offset);
106 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107}
108
109
Michael Schmitzfded3322014-03-31 21:06:05 +1300110/*
111 * This function is called as arch initcall to reserve the pages needed for
112 * ST-RAM management, if the kernel does not reside in ST-RAM.
113 */
114int __init atari_stram_map_pages(void)
115{
116 if (!kernel_in_stram) {
117 /*
118 * Skip page 0, as the fhe first 2 KiB are supervisor-only!
119 */
120 pr_debug("atari_stram pool: kernel not in ST-RAM, using ioremap!\n");
121 stram_pool.start = PAGE_SIZE;
122 stram_pool.end = stram_pool.start + pool_size - 1;
123 request_resource(&iomem_resource, &stram_pool);
124 stram_virt_offset = (unsigned long) ioremap(stram_pool.start,
125 resource_size(&stram_pool)) - stram_pool.start;
126 pr_debug("atari_stram pool: size = %lu bytes, resource = %pR\n",
127 pool_size, &stram_pool);
128 pr_debug("atari_stram pool: stram_virt_offset = %lx\n",
129 stram_virt_offset);
130 }
131 return 0;
132}
133arch_initcall(atari_stram_map_pages);
134
135
136void *atari_stram_to_virt(unsigned long phys)
137{
138 return (void *)(phys + stram_virt_offset);
139}
140EXPORT_SYMBOL(atari_stram_to_virt);
141
142
143unsigned long atari_stram_to_phys(void *virt)
144{
145 return (unsigned long)(virt - stram_virt_offset);
146}
147EXPORT_SYMBOL(atari_stram_to_phys);
148
149
Michael Schmitz217bbd82010-11-01 19:54:00 +0100150void *atari_stram_alloc(unsigned long size, const char *owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151{
Michael Schmitz217bbd82010-11-01 19:54:00 +0100152 struct resource *res;
153 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
Michael Schmitz217bbd82010-11-01 19:54:00 +0100155 pr_debug("atari_stram_alloc: allocate %lu bytes\n", size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
Michael Schmitz217bbd82010-11-01 19:54:00 +0100157 /* round up */
158 size = PAGE_ALIGN(size);
159
160 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
161 if (!res)
162 return NULL;
163
164 res->name = owner;
165 error = allocate_resource(&stram_pool, res, size, 0, UINT_MAX,
166 PAGE_SIZE, NULL, NULL);
167 if (error < 0) {
168 pr_err("atari_stram_alloc: allocate_resource() failed %d!\n",
169 error);
170 kfree(res);
171 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 }
173
Michael Schmitz217bbd82010-11-01 19:54:00 +0100174 pr_debug("atari_stram_alloc: returning %pR\n", res);
Michael Schmitzfded3322014-03-31 21:06:05 +1300175 return atari_stram_to_virt(res->start);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176}
Adrian Bunka3b20042008-02-04 22:30:26 -0800177EXPORT_SYMBOL(atari_stram_alloc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179
Michael Schmitz217bbd82010-11-01 19:54:00 +0100180void atari_stram_free(void *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181{
Michael Schmitzfded3322014-03-31 21:06:05 +1300182 unsigned long start = atari_stram_to_phys(addr);
Michael Schmitz217bbd82010-11-01 19:54:00 +0100183 struct resource *res;
184 unsigned long size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185
Michael Schmitz217bbd82010-11-01 19:54:00 +0100186 res = lookup_resource(&stram_pool, start);
187 if (!res) {
188 pr_err("atari_stram_free: trying to free nonexistent region "
189 "at %p\n", addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 return;
191 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192
Michael Schmitz217bbd82010-11-01 19:54:00 +0100193 size = resource_size(res);
194 pr_debug("atari_stram_free: free %lu bytes at %p\n", size, addr);
195 release_resource(res);
196 kfree(res);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197}
Adrian Bunka3b20042008-02-04 22:30:26 -0800198EXPORT_SYMBOL(atari_stram_free);