xref: /openbmc/linux/drivers/block/z2ram.c (revision 93dc544c)
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 	while ((req = elv_next_request(q)) != NULL) {
74 		unsigned long start = req->sector << 9;
75 		unsigned long len  = req->current_nr_sectors << 9;
76 
77 		if (start + len > z2ram_size) {
78 			printk( KERN_ERR DEVICE_NAME ": bad access: block=%lu, count=%u\n",
79 				req->sector, req->current_nr_sectors);
80 			end_request(req, 0);
81 			continue;
82 		}
83 		while (len) {
84 			unsigned long addr = start & Z2RAM_CHUNKMASK;
85 			unsigned long size = Z2RAM_CHUNKSIZE - addr;
86 			if (len < size)
87 				size = len;
88 			addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
89 			if (rq_data_dir(req) == READ)
90 				memcpy(req->buffer, (char *)addr, size);
91 			else
92 				memcpy((char *)addr, req->buffer, size);
93 			start += size;
94 			len -= size;
95 		}
96 		end_request(req, 1);
97 	}
98 }
99 
100 static void
101 get_z2ram( void )
102 {
103     int i;
104 
105     for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
106     {
107 	if ( test_bit( i, zorro_unused_z2ram ) )
108 	{
109 	    z2_count++;
110 	    z2ram_map[ z2ram_size++ ] =
111 		ZTWO_VADDR( Z2RAM_START ) + ( i << Z2RAM_CHUNKSHIFT );
112 	    clear_bit( i, zorro_unused_z2ram );
113 	}
114     }
115 
116     return;
117 }
118 
119 static void
120 get_chipram( void )
121 {
122 
123     while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
124     {
125 	chip_count++;
126 	z2ram_map[ z2ram_size ] =
127 	    (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
128 
129 	if ( z2ram_map[ z2ram_size ] == 0 )
130 	{
131 	    break;
132 	}
133 
134 	z2ram_size++;
135     }
136 
137     return;
138 }
139 
140 static int
141 z2_open( struct inode *inode, struct file *filp )
142 {
143     int device;
144     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
145 	sizeof( z2ram_map[0] );
146     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
147 	sizeof( z2ram_map[0] );
148     int rc = -ENOMEM;
149 
150     device = iminor(inode);
151 
152     if ( current_device != -1 && current_device != device )
153     {
154 	rc = -EBUSY;
155 	goto err_out;
156     }
157 
158     if ( current_device == -1 )
159     {
160 	z2_count   = 0;
161 	chip_count = 0;
162 	list_count = 0;
163 	z2ram_size = 0;
164 
165 	/* Use a specific list entry. */
166 	if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
167 		int index = device - Z2MINOR_MEMLIST1 + 1;
168 		unsigned long size, paddr, vaddr;
169 
170 		if (index >= m68k_realnum_memory) {
171 			printk( KERN_ERR DEVICE_NAME
172 				": no such entry in z2ram_map\n" );
173 		        goto err_out;
174 		}
175 
176 		paddr = m68k_memory[index].addr;
177 		size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
178 
179 #ifdef __powerpc__
180 		/* FIXME: ioremap doesn't build correct memory tables. */
181 		{
182 			vfree(vmalloc (size));
183 		}
184 
185 		vaddr = (unsigned long) __ioremap (paddr, size,
186 						   _PAGE_WRITETHRU);
187 
188 #else
189 		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
190 #endif
191 		z2ram_map =
192 			kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
193 				GFP_KERNEL);
194 		if ( z2ram_map == NULL )
195 		{
196 		    printk( KERN_ERR DEVICE_NAME
197 			": cannot get mem for z2ram_map\n" );
198 		    goto err_out;
199 		}
200 
201 		while (size) {
202 			z2ram_map[ z2ram_size++ ] = vaddr;
203 			size -= Z2RAM_CHUNKSIZE;
204 			vaddr += Z2RAM_CHUNKSIZE;
205 			list_count++;
206 		}
207 
208 		if ( z2ram_size != 0 )
209 		    printk( KERN_INFO DEVICE_NAME
210 			": using %iK List Entry %d Memory\n",
211 			list_count * Z2RAM_CHUNK1024, index );
212 	} else
213 
214 	switch ( device )
215 	{
216 	    case Z2MINOR_COMBINED:
217 
218 		z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
219 		if ( z2ram_map == NULL )
220 		{
221 		    printk( KERN_ERR DEVICE_NAME
222 			": cannot get mem for z2ram_map\n" );
223 		    goto err_out;
224 		}
225 
226 		get_z2ram();
227 		get_chipram();
228 
229 		if ( z2ram_size != 0 )
230 		    printk( KERN_INFO DEVICE_NAME
231 			": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
232 			z2_count * Z2RAM_CHUNK1024,
233 			chip_count * Z2RAM_CHUNK1024,
234 			( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
235 
236 	    break;
237 
238     	    case Z2MINOR_Z2ONLY:
239 		z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
240 		if ( z2ram_map == NULL )
241 		{
242 		    printk( KERN_ERR DEVICE_NAME
243 			": cannot get mem for z2ram_map\n" );
244 		    goto err_out;
245 		}
246 
247 		get_z2ram();
248 
249 		if ( z2ram_size != 0 )
250 		    printk( KERN_INFO DEVICE_NAME
251 			": using %iK of Zorro II RAM\n",
252 			z2_count * Z2RAM_CHUNK1024 );
253 
254 	    break;
255 
256 	    case Z2MINOR_CHIPONLY:
257 		z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
258 		if ( z2ram_map == NULL )
259 		{
260 		    printk( KERN_ERR DEVICE_NAME
261 			": cannot get mem for z2ram_map\n" );
262 		    goto err_out;
263 		}
264 
265 		get_chipram();
266 
267 		if ( z2ram_size != 0 )
268 		    printk( KERN_INFO DEVICE_NAME
269 			": using %iK Chip RAM\n",
270 			chip_count * Z2RAM_CHUNK1024 );
271 
272 	    break;
273 
274 	    default:
275 		rc = -ENODEV;
276 		goto err_out;
277 
278 	    break;
279 	}
280 
281 	if ( z2ram_size == 0 )
282 	{
283 	    printk( KERN_NOTICE DEVICE_NAME
284 		": no unused ZII/Chip RAM found\n" );
285 	    goto err_out_kfree;
286 	}
287 
288 	current_device = device;
289 	z2ram_size <<= Z2RAM_CHUNKSHIFT;
290 	set_capacity(z2ram_gendisk, z2ram_size >> 9);
291     }
292 
293     return 0;
294 
295 err_out_kfree:
296     kfree(z2ram_map);
297 err_out:
298     return rc;
299 }
300 
301 static int
302 z2_release( struct inode *inode, struct file *filp )
303 {
304     if ( current_device == -1 )
305 	return 0;
306 
307     /*
308      * FIXME: unmap memory
309      */
310 
311     return 0;
312 }
313 
314 static struct block_device_operations z2_fops =
315 {
316 	.owner		= THIS_MODULE,
317 	.open		= z2_open,
318 	.release	= z2_release,
319 };
320 
321 static struct kobject *z2_find(dev_t dev, int *part, void *data)
322 {
323 	*part = 0;
324 	return get_disk(z2ram_gendisk);
325 }
326 
327 static struct request_queue *z2_queue;
328 
329 static int __init
330 z2_init(void)
331 {
332     int ret;
333 
334     if (!MACH_IS_AMIGA)
335 	return -ENODEV;
336 
337     ret = -EBUSY;
338     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
339 	goto err;
340 
341     ret = -ENOMEM;
342     z2ram_gendisk = alloc_disk(1);
343     if (!z2ram_gendisk)
344 	goto out_disk;
345 
346     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
347     if (!z2_queue)
348 	goto out_queue;
349 
350     z2ram_gendisk->major = Z2RAM_MAJOR;
351     z2ram_gendisk->first_minor = 0;
352     z2ram_gendisk->fops = &z2_fops;
353     sprintf(z2ram_gendisk->disk_name, "z2ram");
354 
355     z2ram_gendisk->queue = z2_queue;
356     add_disk(z2ram_gendisk);
357     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
358 				z2_find, NULL, NULL);
359 
360     return 0;
361 
362 out_queue:
363     put_disk(z2ram_gendisk);
364 out_disk:
365     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
366 err:
367     return ret;
368 }
369 
370 static void __exit z2_exit(void)
371 {
372     int i, j;
373     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), 256);
374     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
375     del_gendisk(z2ram_gendisk);
376     put_disk(z2ram_gendisk);
377     blk_cleanup_queue(z2_queue);
378 
379     if ( current_device != -1 )
380     {
381 	i = 0;
382 
383 	for ( j = 0 ; j < z2_count; j++ )
384 	{
385 	    set_bit( i++, zorro_unused_z2ram );
386 	}
387 
388 	for ( j = 0 ; j < chip_count; j++ )
389 	{
390 	    if ( z2ram_map[ i ] )
391 	    {
392 		amiga_chip_free( (void *) z2ram_map[ i++ ] );
393 	    }
394 	}
395 
396 	if ( z2ram_map != NULL )
397 	{
398 	    kfree( z2ram_map );
399 	}
400     }
401 
402     return;
403 }
404 
405 module_init(z2_init);
406 module_exit(z2_exit);
407 MODULE_LICENSE("GPL");
408