xref: /linux/drivers/block/z2ram.c (revision 040932cdcfca9b0ac55a4f74f194c2e2c8a2527b)
1 /*
2 ** z2ram - Amiga pseudo-driver to access 16bit-RAM in ZorroII space
3 **         as a block device, to be used as a RAM disk or swap space
4 **
5 ** Copyright (C) 1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
6 **
7 ** ++Geert: support for zorro_unused_z2ram, better range checking
8 ** ++roman: translate accesses via an array
9 ** ++Milan: support for ChipRAM usage
10 ** ++yambo: converted to 2.0 kernel
11 ** ++yambo: modularized and support added for 3 minor devices including:
12 **          MAJOR  MINOR  DESCRIPTION
13 **          -----  -----  ----------------------------------------------
14 **          37     0       Use Zorro II and Chip ram
15 **          37     1       Use only Zorro II ram
16 **          37     2       Use only Chip ram
17 **          37     4-7     Use memory list entry 1-4 (first is 0)
18 ** ++jskov: support for 1-4th memory list entry.
19 **
20 ** Permission to use, copy, modify, and distribute this software and its
21 ** documentation for any purpose and without fee is hereby granted, provided
22 ** that the above copyright notice appear in all copies and that both that
23 ** copyright notice and this permission notice appear in supporting
24 ** documentation.  This software is provided "as is" without express or
25 ** implied warranty.
26 */
27 
28 #define DEVICE_NAME "Z2RAM"
29 
30 #include <linux/major.h>
31 #include <linux/vmalloc.h>
32 #include <linux/init.h>
33 #include <linux/module.h>
34 #include <linux/blkdev.h>
35 #include <linux/bitops.h>
36 
37 #include <asm/setup.h>
38 #include <asm/amigahw.h>
39 #include <asm/pgtable.h>
40 
41 #include <linux/zorro.h>
42 
43 
44 extern int m68k_realnum_memory;
45 extern struct mem_info m68k_memory[NUM_MEMINFO];
46 
47 #define Z2MINOR_COMBINED      (0)
48 #define Z2MINOR_Z2ONLY        (1)
49 #define Z2MINOR_CHIPONLY      (2)
50 #define Z2MINOR_MEMLIST1      (4)
51 #define Z2MINOR_MEMLIST2      (5)
52 #define Z2MINOR_MEMLIST3      (6)
53 #define Z2MINOR_MEMLIST4      (7)
54 #define Z2MINOR_COUNT         (8) /* Move this down when adding a new minor */
55 
56 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
57 
58 static u_long *z2ram_map    = NULL;
59 static u_long z2ram_size    = 0;
60 static int z2_count         = 0;
61 static int chip_count       = 0;
62 static int list_count       = 0;
63 static int current_device   = -1;
64 
65 static DEFINE_SPINLOCK(z2ram_lock);
66 
67 static struct block_device_operations z2_fops;
68 static struct gendisk *z2ram_gendisk;
69 
70 static void do_z2_request(struct request_queue *q)
71 {
72 	struct request *req;
73 
74 	req = blk_fetch_request(q);
75 	while (req) {
76 		unsigned long start = blk_rq_pos(req) << 9;
77 		unsigned long len  = blk_rq_cur_bytes(req);
78 		int err = 0;
79 
80 		if (start + len > z2ram_size) {
81 			printk( KERN_ERR DEVICE_NAME ": bad access: block=%lu, count=%u\n",
82 				blk_rq_pos(req), blk_rq_cur_sectors(req));
83 			err = -EIO;
84 			goto done;
85 		}
86 		while (len) {
87 			unsigned long addr = start & Z2RAM_CHUNKMASK;
88 			unsigned long size = Z2RAM_CHUNKSIZE - addr;
89 			if (len < size)
90 				size = len;
91 			addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
92 			if (rq_data_dir(req) == READ)
93 				memcpy(req->buffer, (char *)addr, size);
94 			else
95 				memcpy((char *)addr, req->buffer, size);
96 			start += size;
97 			len -= size;
98 		}
99 	done:
100 		if (!__blk_end_request_cur(req, err))
101 			req = blk_fetch_request(q);
102 	}
103 }
104 
105 static void
106 get_z2ram( void )
107 {
108     int i;
109 
110     for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
111     {
112 	if ( test_bit( i, zorro_unused_z2ram ) )
113 	{
114 	    z2_count++;
115 	    z2ram_map[ z2ram_size++ ] =
116 		ZTWO_VADDR( Z2RAM_START ) + ( i << Z2RAM_CHUNKSHIFT );
117 	    clear_bit( i, zorro_unused_z2ram );
118 	}
119     }
120 
121     return;
122 }
123 
124 static void
125 get_chipram( void )
126 {
127 
128     while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
129     {
130 	chip_count++;
131 	z2ram_map[ z2ram_size ] =
132 	    (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
133 
134 	if ( z2ram_map[ z2ram_size ] == 0 )
135 	{
136 	    break;
137 	}
138 
139 	z2ram_size++;
140     }
141 
142     return;
143 }
144 
145 static int z2_open(struct block_device *bdev, fmode_t mode)
146 {
147     int device;
148     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
149 	sizeof( z2ram_map[0] );
150     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
151 	sizeof( z2ram_map[0] );
152     int rc = -ENOMEM;
153 
154     device = MINOR(bdev->bd_dev);
155 
156     if ( current_device != -1 && current_device != device )
157     {
158 	rc = -EBUSY;
159 	goto err_out;
160     }
161 
162     if ( current_device == -1 )
163     {
164 	z2_count   = 0;
165 	chip_count = 0;
166 	list_count = 0;
167 	z2ram_size = 0;
168 
169 	/* Use a specific list entry. */
170 	if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
171 		int index = device - Z2MINOR_MEMLIST1 + 1;
172 		unsigned long size, paddr, vaddr;
173 
174 		if (index >= m68k_realnum_memory) {
175 			printk( KERN_ERR DEVICE_NAME
176 				": no such entry in z2ram_map\n" );
177 		        goto err_out;
178 		}
179 
180 		paddr = m68k_memory[index].addr;
181 		size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
182 
183 #ifdef __powerpc__
184 		/* FIXME: ioremap doesn't build correct memory tables. */
185 		{
186 			vfree(vmalloc (size));
187 		}
188 
189 		vaddr = (unsigned long) __ioremap (paddr, size,
190 						   _PAGE_WRITETHRU);
191 
192 #else
193 		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
194 #endif
195 		z2ram_map =
196 			kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
197 				GFP_KERNEL);
198 		if ( z2ram_map == NULL )
199 		{
200 		    printk( KERN_ERR DEVICE_NAME
201 			": cannot get mem for z2ram_map\n" );
202 		    goto err_out;
203 		}
204 
205 		while (size) {
206 			z2ram_map[ z2ram_size++ ] = vaddr;
207 			size -= Z2RAM_CHUNKSIZE;
208 			vaddr += Z2RAM_CHUNKSIZE;
209 			list_count++;
210 		}
211 
212 		if ( z2ram_size != 0 )
213 		    printk( KERN_INFO DEVICE_NAME
214 			": using %iK List Entry %d Memory\n",
215 			list_count * Z2RAM_CHUNK1024, index );
216 	} else
217 
218 	switch ( device )
219 	{
220 	    case Z2MINOR_COMBINED:
221 
222 		z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
223 		if ( z2ram_map == NULL )
224 		{
225 		    printk( KERN_ERR DEVICE_NAME
226 			": cannot get mem for z2ram_map\n" );
227 		    goto err_out;
228 		}
229 
230 		get_z2ram();
231 		get_chipram();
232 
233 		if ( z2ram_size != 0 )
234 		    printk( KERN_INFO DEVICE_NAME
235 			": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
236 			z2_count * Z2RAM_CHUNK1024,
237 			chip_count * Z2RAM_CHUNK1024,
238 			( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
239 
240 	    break;
241 
242     	    case Z2MINOR_Z2ONLY:
243 		z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
244 		if ( z2ram_map == NULL )
245 		{
246 		    printk( KERN_ERR DEVICE_NAME
247 			": cannot get mem for z2ram_map\n" );
248 		    goto err_out;
249 		}
250 
251 		get_z2ram();
252 
253 		if ( z2ram_size != 0 )
254 		    printk( KERN_INFO DEVICE_NAME
255 			": using %iK of Zorro II RAM\n",
256 			z2_count * Z2RAM_CHUNK1024 );
257 
258 	    break;
259 
260 	    case Z2MINOR_CHIPONLY:
261 		z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
262 		if ( z2ram_map == NULL )
263 		{
264 		    printk( KERN_ERR DEVICE_NAME
265 			": cannot get mem for z2ram_map\n" );
266 		    goto err_out;
267 		}
268 
269 		get_chipram();
270 
271 		if ( z2ram_size != 0 )
272 		    printk( KERN_INFO DEVICE_NAME
273 			": using %iK Chip RAM\n",
274 			chip_count * Z2RAM_CHUNK1024 );
275 
276 	    break;
277 
278 	    default:
279 		rc = -ENODEV;
280 		goto err_out;
281 
282 	    break;
283 	}
284 
285 	if ( z2ram_size == 0 )
286 	{
287 	    printk( KERN_NOTICE DEVICE_NAME
288 		": no unused ZII/Chip RAM found\n" );
289 	    goto err_out_kfree;
290 	}
291 
292 	current_device = device;
293 	z2ram_size <<= Z2RAM_CHUNKSHIFT;
294 	set_capacity(z2ram_gendisk, z2ram_size >> 9);
295     }
296 
297     return 0;
298 
299 err_out_kfree:
300     kfree(z2ram_map);
301 err_out:
302     return rc;
303 }
304 
305 static int
306 z2_release(struct gendisk *disk, fmode_t mode)
307 {
308     if ( current_device == -1 )
309 	return 0;
310 
311     /*
312      * FIXME: unmap memory
313      */
314 
315     return 0;
316 }
317 
318 static struct block_device_operations z2_fops =
319 {
320 	.owner		= THIS_MODULE,
321 	.open		= z2_open,
322 	.release	= z2_release,
323 };
324 
325 static struct kobject *z2_find(dev_t dev, int *part, void *data)
326 {
327 	*part = 0;
328 	return get_disk(z2ram_gendisk);
329 }
330 
331 static struct request_queue *z2_queue;
332 
333 static int __init
334 z2_init(void)
335 {
336     int ret;
337 
338     if (!MACH_IS_AMIGA)
339 	return -ENODEV;
340 
341     ret = -EBUSY;
342     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
343 	goto err;
344 
345     ret = -ENOMEM;
346     z2ram_gendisk = alloc_disk(1);
347     if (!z2ram_gendisk)
348 	goto out_disk;
349 
350     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
351     if (!z2_queue)
352 	goto out_queue;
353 
354     z2ram_gendisk->major = Z2RAM_MAJOR;
355     z2ram_gendisk->first_minor = 0;
356     z2ram_gendisk->fops = &z2_fops;
357     sprintf(z2ram_gendisk->disk_name, "z2ram");
358 
359     z2ram_gendisk->queue = z2_queue;
360     add_disk(z2ram_gendisk);
361     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
362 				z2_find, NULL, NULL);
363 
364     return 0;
365 
366 out_queue:
367     put_disk(z2ram_gendisk);
368 out_disk:
369     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
370 err:
371     return ret;
372 }
373 
374 static void __exit z2_exit(void)
375 {
376     int i, j;
377     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT);
378     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
379     del_gendisk(z2ram_gendisk);
380     put_disk(z2ram_gendisk);
381     blk_cleanup_queue(z2_queue);
382 
383     if ( current_device != -1 )
384     {
385 	i = 0;
386 
387 	for ( j = 0 ; j < z2_count; j++ )
388 	{
389 	    set_bit( i++, zorro_unused_z2ram );
390 	}
391 
392 	for ( j = 0 ; j < chip_count; j++ )
393 	{
394 	    if ( z2ram_map[ i ] )
395 	    {
396 		amiga_chip_free( (void *) z2ram_map[ i++ ] );
397 	    }
398 	}
399 
400 	if ( z2ram_map != NULL )
401 	{
402 	    kfree( z2ram_map );
403 	}
404     }
405 
406     return;
407 }
408 
409 module_init(z2_init);
410 module_exit(z2_exit);
411 MODULE_LICENSE("GPL");
412