aboutsummaryrefslogtreecommitdiffstats
path: root/arch/m68k/atari
diff options
context:
space:
mode:
Diffstat (limited to 'arch/m68k/atari')
-rw-r--r--arch/m68k/atari/stram.c354
1 files changed, 69 insertions, 285 deletions
diff --git a/arch/m68k/atari/stram.c b/arch/m68k/atari/stram.c
index 6ec3b7f3377..0810c8d56e5 100644
--- a/arch/m68k/atari/stram.c
+++ b/arch/m68k/atari/stram.c
@@ -1,5 +1,5 @@
1/* 1/*
2 * arch/m68k/atari/stram.c: Functions for ST-RAM allocations 2 * Functions for ST-RAM allocations
3 * 3 *
4 * Copyright 1994-97 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de> 4 * Copyright 1994-97 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
5 * 5 *
@@ -30,91 +30,35 @@
30#include <asm/atari_stram.h> 30#include <asm/atari_stram.h>
31#include <asm/io.h> 31#include <asm/io.h>
32 32
33#undef DEBUG
34
35#ifdef DEBUG
36#define DPRINTK(fmt,args...) printk( fmt, ##args )
37#else
38#define DPRINTK(fmt,args...)
39#endif
40
41#if defined(CONFIG_PROC_FS) && defined(CONFIG_STRAM_PROC)
42/* abbrev for the && above... */
43#define DO_PROC
44#include <linux/proc_fs.h>
45#include <linux/seq_file.h>
46#endif
47 33
48/* 34/*
49 * ++roman: 35 * The ST-RAM allocator allocates memory from a pool of reserved ST-RAM of
50 * 36 * configurable size, set aside on ST-RAM init.
51 * New version of ST-Ram buffer allocation. Instead of using the 37 * As long as this pool is not exhausted, allocation of real ST-RAM can be
52 * 1 MB - 4 KB that remain when the ST-Ram chunk starts at $1000 38 * guaranteed.
53 * (1 MB granularity!), such buffers are reserved like this:
54 *
55 * - If the kernel resides in ST-Ram anyway, we can take the buffer
56 * from behind the current kernel data space the normal way
57 * (incrementing start_mem).
58 *
59 * - If the kernel is in TT-Ram, stram_init() initializes start and
60 * end of the available region. Buffers are allocated from there
61 * and mem_init() later marks the such used pages as reserved.
62 * Since each TT-Ram chunk is at least 4 MB in size, I hope there
63 * won't be an overrun of the ST-Ram region by normal kernel data
64 * space.
65 *
66 * For that, ST-Ram may only be allocated while kernel initialization
67 * is going on, or exactly: before mem_init() is called. There is also
68 * no provision now for freeing ST-Ram buffers. It seems that isn't
69 * really needed.
70 *
71 */ 39 */
72 40
73/* Start and end (virtual) of ST-RAM */
74static void *stram_start, *stram_end;
75
76/* set after memory_init() executed and allocations via start_mem aren't
77 * possible anymore */
78static int mem_init_done;
79
80/* set if kernel is in ST-RAM */ 41/* set if kernel is in ST-RAM */
81static int kernel_in_stram; 42static int kernel_in_stram;
82 43
83typedef struct stram_block { 44static struct resource stram_pool = {
84 struct stram_block *next; 45 .name = "ST-RAM Pool"
85 void *start; 46};
86 unsigned long size;
87 unsigned flags;
88 const char *owner;
89} BLOCK;
90
91/* values for flags field */
92#define BLOCK_FREE 0x01 /* free structure in the BLOCKs pool */
93#define BLOCK_KMALLOCED 0x02 /* structure allocated by kmalloc() */
94#define BLOCK_GFP 0x08 /* block allocated with __get_dma_pages() */
95 47
96/* list of allocated blocks */ 48static unsigned long pool_size = 1024*1024;
97static BLOCK *alloc_list;
98 49
99/* We can't always use kmalloc() to allocate BLOCK structures, since
100 * stram_alloc() can be called rather early. So we need some pool of
101 * statically allocated structures. 20 of them is more than enough, so in most
102 * cases we never should need to call kmalloc(). */
103#define N_STATIC_BLOCKS 20
104static BLOCK static_blocks[N_STATIC_BLOCKS];
105 50
106/***************************** Prototypes *****************************/ 51static int __init atari_stram_setup(char *arg)
52{
53 if (!MACH_IS_ATARI)
54 return 0;
107 55
108static BLOCK *add_region( void *addr, unsigned long size ); 56 pool_size = memparse(arg, NULL);
109static BLOCK *find_region( void *addr ); 57 return 0;
110static int remove_region( BLOCK *block ); 58}
111 59
112/************************* End of Prototypes **************************/ 60early_param("stram_pool", atari_stram_setup);
113 61
114
115/* ------------------------------------------------------------------------ */
116/* Public Interface */
117/* ------------------------------------------------------------------------ */
118 62
119/* 63/*
120 * This init function is called very early by atari/config.c 64 * This init function is called very early by atari/config.c
@@ -123,25 +67,23 @@ static int remove_region( BLOCK *block );
123void __init atari_stram_init(void) 67void __init atari_stram_init(void)
124{ 68{
125 int i; 69 int i;
70 void *stram_start;
126 71
127 /* initialize static blocks */ 72 /*
128 for( i = 0; i < N_STATIC_BLOCKS; ++i ) 73 * determine whether kernel code resides in ST-RAM
129 static_blocks[i].flags = BLOCK_FREE; 74 * (then ST-RAM is the first memory block at virtual 0x0)
130 75 */
131 /* determine whether kernel code resides in ST-RAM (then ST-RAM is the
132 * first memory block at virtual 0x0) */
133 stram_start = phys_to_virt(0); 76 stram_start = phys_to_virt(0);
134 kernel_in_stram = (stram_start == 0); 77 kernel_in_stram = (stram_start == 0);
135 78
136 for( i = 0; i < m68k_num_memory; ++i ) { 79 for (i = 0; i < m68k_num_memory; ++i) {
137 if (m68k_memory[i].addr == 0) { 80 if (m68k_memory[i].addr == 0) {
138 /* skip first 2kB or page (supervisor-only!) */
139 stram_end = stram_start + m68k_memory[i].size;
140 return; 81 return;
141 } 82 }
142 } 83 }
84
143 /* Should never come here! (There is always ST-Ram!) */ 85 /* Should never come here! (There is always ST-Ram!) */
144 panic( "atari_stram_init: no ST-RAM found!" ); 86 panic("atari_stram_init: no ST-RAM found!");
145} 87}
146 88
147 89
@@ -151,226 +93,68 @@ void __init atari_stram_init(void)
151 */ 93 */
152void __init atari_stram_reserve_pages(void *start_mem) 94void __init atari_stram_reserve_pages(void *start_mem)
153{ 95{
154 /* always reserve first page of ST-RAM, the first 2 kB are 96 /*
155 * supervisor-only! */ 97 * always reserve first page of ST-RAM, the first 2 KiB are
98 * supervisor-only!
99 */
156 if (!kernel_in_stram) 100 if (!kernel_in_stram)
157 reserve_bootmem(0, PAGE_SIZE, BOOTMEM_DEFAULT); 101 reserve_bootmem(0, PAGE_SIZE, BOOTMEM_DEFAULT);
158 102
159} 103 stram_pool.start = (resource_size_t)alloc_bootmem_low_pages(pool_size);
104 stram_pool.end = stram_pool.start + pool_size - 1;
105 request_resource(&iomem_resource, &stram_pool);
160 106
161void atari_stram_mem_init_hook (void) 107 pr_debug("atari_stram pool: size = %lu bytes, resource = %pR\n",
162{ 108 pool_size, &stram_pool);
163 mem_init_done = 1;
164} 109}
165 110
166 111
167/* 112void *atari_stram_alloc(unsigned long size, const char *owner)
168 * This is main public interface: somehow allocate a ST-RAM block
169 *
170 * - If we're before mem_init(), we have to make a static allocation. The
171 * region is taken in the kernel data area (if the kernel is in ST-RAM) or
172 * from the start of ST-RAM (if the kernel is in TT-RAM) and added to the
173 * rsvd_stram_* region. The ST-RAM is somewhere in the middle of kernel
174 * address space in the latter case.
175 *
176 * - If mem_init() already has been called, try with __get_dma_pages().
177 * This has the disadvantage that it's very hard to get more than 1 page,
178 * and it is likely to fail :-(
179 *
180 */
181void *atari_stram_alloc(long size, const char *owner)
182{ 113{
183 void *addr = NULL; 114 struct resource *res;
184 BLOCK *block; 115 int error;
185 int flags; 116
186 117 pr_debug("atari_stram_alloc: allocate %lu bytes\n", size);
187 DPRINTK("atari_stram_alloc(size=%08lx,owner=%s)\n", size, owner); 118
188 119 /* round up */
189 if (!mem_init_done) 120 size = PAGE_ALIGN(size);
190 return alloc_bootmem_low(size); 121
191 else { 122 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
192 /* After mem_init(): can only resort to __get_dma_pages() */ 123 if (!res)
193 addr = (void *)__get_dma_pages(GFP_KERNEL, get_order(size)); 124 return NULL;
194 flags = BLOCK_GFP; 125
195 DPRINTK( "atari_stram_alloc: after mem_init, " 126 res->name = owner;
196 "get_pages=%p\n", addr ); 127 error = allocate_resource(&stram_pool, res, size, 0, UINT_MAX,
128 PAGE_SIZE, NULL, NULL);
129 if (error < 0) {
130 pr_err("atari_stram_alloc: allocate_resource() failed %d!\n",
131 error);
132 kfree(res);
133 return NULL;
197 } 134 }
198 135
199 if (addr) { 136 pr_debug("atari_stram_alloc: returning %pR\n", res);
200 if (!(block = add_region( addr, size ))) { 137 return (void *)res->start;
201 /* out of memory for BLOCK structure :-( */
202 DPRINTK( "atari_stram_alloc: out of mem for BLOCK -- "
203 "freeing again\n" );
204 free_pages((unsigned long)addr, get_order(size));
205 return( NULL );
206 }
207 block->owner = owner;
208 block->flags |= flags;
209 }
210 return( addr );
211} 138}
212EXPORT_SYMBOL(atari_stram_alloc); 139EXPORT_SYMBOL(atari_stram_alloc);
213 140
214void atari_stram_free( void *addr )
215 141
142void atari_stram_free(void *addr)
216{ 143{
217 BLOCK *block; 144 unsigned long start = (unsigned long)addr;
218 145 struct resource *res;
219 DPRINTK( "atari_stram_free(addr=%p)\n", addr ); 146 unsigned long size;
220 147
221 if (!(block = find_region( addr ))) { 148 res = lookup_resource(&stram_pool, start);
222 printk( KERN_ERR "Attempt to free non-allocated ST-RAM block at %p " 149 if (!res) {
223 "from %p\n", addr, __builtin_return_address(0) ); 150 pr_err("atari_stram_free: trying to free nonexistent region "
151 "at %p\n", addr);
224 return; 152 return;
225 } 153 }
226 DPRINTK( "atari_stram_free: found block (%p): size=%08lx, owner=%s, "
227 "flags=%02x\n", block, block->size, block->owner, block->flags );
228
229 if (!(block->flags & BLOCK_GFP))
230 goto fail;
231 154
232 DPRINTK("atari_stram_free: is kmalloced, order_size=%d\n", 155 size = resource_size(res);
233 get_order(block->size)); 156 pr_debug("atari_stram_free: free %lu bytes at %p\n", size, addr);
234 free_pages((unsigned long)addr, get_order(block->size)); 157 release_resource(res);
235 remove_region( block ); 158 kfree(res);
236 return;
237
238 fail:
239 printk( KERN_ERR "atari_stram_free: cannot free block at %p "
240 "(called from %p)\n", addr, __builtin_return_address(0) );
241} 159}
242EXPORT_SYMBOL(atari_stram_free); 160EXPORT_SYMBOL(atari_stram_free);
243
244
245/* ------------------------------------------------------------------------ */
246/* Region Management */
247/* ------------------------------------------------------------------------ */
248
249
250/* insert a region into the alloced list (sorted) */
251static BLOCK *add_region( void *addr, unsigned long size )
252{
253 BLOCK **p, *n = NULL;
254 int i;
255
256 for( i = 0; i < N_STATIC_BLOCKS; ++i ) {
257 if (static_blocks[i].flags & BLOCK_FREE) {
258 n = &static_blocks[i];
259 n->flags = 0;
260 break;
261 }
262 }
263 if (!n && mem_init_done) {
264 /* if statics block pool exhausted and we can call kmalloc() already
265 * (after mem_init()), try that */
266 n = kmalloc( sizeof(BLOCK), GFP_KERNEL );
267 if (n)
268 n->flags = BLOCK_KMALLOCED;
269 }
270 if (!n) {
271 printk( KERN_ERR "Out of memory for ST-RAM descriptor blocks\n" );
272 return( NULL );
273 }
274 n->start = addr;
275 n->size = size;
276
277 for( p = &alloc_list; *p; p = &((*p)->next) )
278 if ((*p)->start > addr) break;
279 n->next = *p;
280 *p = n;
281
282 return( n );
283}
284
285
286/* find a region (by start addr) in the alloced list */
287static BLOCK *find_region( void *addr )
288{
289 BLOCK *p;
290
291 for( p = alloc_list; p; p = p->next ) {
292 if (p->start == addr)
293 return( p );
294 if (p->start > addr)
295 break;
296 }
297 return( NULL );
298}
299
300
301/* remove a block from the alloced list */
302static int remove_region( BLOCK *block )
303{
304 BLOCK **p;
305
306 for( p = &alloc_list; *p; p = &((*p)->next) )
307 if (*p == block) break;
308 if (!*p)
309 return( 0 );
310
311 *p = block->next;
312 if (block->flags & BLOCK_KMALLOCED)
313 kfree( block );
314 else
315 block->flags |= BLOCK_FREE;
316 return( 1 );
317}
318
319
320
321/* ------------------------------------------------------------------------ */
322/* /proc statistics file stuff */
323/* ------------------------------------------------------------------------ */
324
325#ifdef DO_PROC
326
327#define PRINT_PROC(fmt,args...) seq_printf( m, fmt, ##args )
328
329static int stram_proc_show(struct seq_file *m, void *v)
330{
331 BLOCK *p;
332
333 PRINT_PROC("Total ST-RAM: %8u kB\n",
334 (stram_end - stram_start) >> 10);
335 PRINT_PROC( "Allocated regions:\n" );
336 for( p = alloc_list; p; p = p->next ) {
337 PRINT_PROC("0x%08lx-0x%08lx: %s (",
338 virt_to_phys(p->start),
339 virt_to_phys(p->start+p->size-1),
340 p->owner);
341 if (p->flags & BLOCK_GFP)
342 PRINT_PROC( "page-alloced)\n" );
343 else
344 PRINT_PROC( "??)\n" );
345 }
346
347 return 0;
348}
349
350static int stram_proc_open(struct inode *inode, struct file *file)
351{
352 return single_open(file, stram_proc_show, NULL);
353}
354
355static const struct file_operations stram_proc_fops = {
356 .open = stram_proc_open,
357 .read = seq_read,
358 .llseek = seq_lseek,
359 .release = single_release,
360};
361
362static int __init proc_stram_init(void)
363{
364 proc_create("stram", 0, NULL, &stram_proc_fops);
365 return 0;
366}
367module_init(proc_stram_init);
368#endif
369
370
371/*
372 * Local variables:
373 * c-indent-level: 4
374 * tab-width: 4
375 * End:
376 */