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2 * Functions for ST-RAM allocations
4 * Copyright 1994-97 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
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
11 #include <linux/types.h>
12 #include <linux/kernel.h>
14 #include <linux/kdev_t.h>
15 #include <linux/major.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
19 #include <linux/pagemap.h>
20 #include <linux/bootmem.h>
21 #include <linux/mount.h>
22 #include <linux/blkdev.h>
23 #include <linux/module.h>
24 #include <linux/ioport.h>
26 #include <asm/setup.h>
27 #include <asm/machdep.h>
29 #include <asm/pgtable.h>
30 #include <asm/atarihw.h>
31 #include <asm/atari_stram.h>
36 * 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
42 /* set if kernel is in ST-RAM */
43 static int kernel_in_stram
;
45 static struct resource stram_pool
= {
49 static unsigned long pool_size
= 1024*1024;
51 static unsigned long stram_virt_offset
;
53 static int __init
atari_stram_setup(char *arg
)
58 pool_size
= memparse(arg
, NULL
);
62 early_param("stram_pool", atari_stram_setup
);
66 * This init function is called very early by atari/config.c
67 * It initializes some internal variables needed for stram_alloc()
69 void __init
atari_stram_init(void)
74 * determine whether kernel code resides in ST-RAM
75 * (then ST-RAM is the first memory block at virtual 0x0)
77 kernel_in_stram
= (m68k_memory
[0].addr
== 0);
79 for (i
= 0; i
< m68k_num_memory
; ++i
) {
80 if (m68k_memory
[i
].addr
== 0) {
85 /* Should never come here! (There is always ST-Ram!) */
86 panic("atari_stram_init: no ST-RAM found!");
91 * This function is called from setup_arch() to reserve the pages needed for
92 * ST-RAM management, if the kernel resides in ST-RAM.
94 void __init
atari_stram_reserve_pages(void *start_mem
)
96 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",
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.
114 int __init
atari_stram_map_pages(void)
116 if (!kernel_in_stram
) {
118 * Skip page 0, as the fhe first 2 KiB are supervisor-only!
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",
133 arch_initcall(atari_stram_map_pages
);
136 void *atari_stram_to_virt(unsigned long phys
)
138 return (void *)(phys
+ stram_virt_offset
);
140 EXPORT_SYMBOL(atari_stram_to_virt
);
143 unsigned long atari_stram_to_phys(void *virt
)
145 return (unsigned long)(virt
- stram_virt_offset
);
147 EXPORT_SYMBOL(atari_stram_to_phys
);
150 void *atari_stram_alloc(unsigned long size
, const char *owner
)
152 struct resource
*res
;
155 pr_debug("atari_stram_alloc: allocate %lu bytes\n", size
);
158 size
= PAGE_ALIGN(size
);
160 res
= kzalloc(sizeof(struct resource
), GFP_KERNEL
);
165 error
= allocate_resource(&stram_pool
, res
, size
, 0, UINT_MAX
,
166 PAGE_SIZE
, NULL
, NULL
);
168 pr_err("atari_stram_alloc: allocate_resource() failed %d!\n",
174 pr_debug("atari_stram_alloc: returning %pR\n", res
);
175 return atari_stram_to_virt(res
->start
);
177 EXPORT_SYMBOL(atari_stram_alloc
);
180 void atari_stram_free(void *addr
)
182 unsigned long start
= atari_stram_to_phys(addr
);
183 struct resource
*res
;
186 res
= lookup_resource(&stram_pool
, start
);
188 pr_err("atari_stram_free: trying to free nonexistent region "
193 size
= resource_size(res
);
194 pr_debug("atari_stram_free: free %lu bytes at %p\n", size
, addr
);
195 release_resource(res
);
198 EXPORT_SYMBOL(atari_stram_free
);