xref: /openbmc/linux/drivers/block/z2ram.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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 z2_open(struct block_device *bdev, fmode_t mode)
141 {
142     int device;
143     int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
144 	sizeof( z2ram_map[0] );
145     int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
146 	sizeof( z2ram_map[0] );
147     int rc = -ENOMEM;
148 
149     device = MINOR(bdev->bd_dev);
150 
151     if ( current_device != -1 && current_device != device )
152     {
153 	rc = -EBUSY;
154 	goto err_out;
155     }
156 
157     if ( current_device == -1 )
158     {
159 	z2_count   = 0;
160 	chip_count = 0;
161 	list_count = 0;
162 	z2ram_size = 0;
163 
164 	/* Use a specific list entry. */
165 	if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
166 		int index = device - Z2MINOR_MEMLIST1 + 1;
167 		unsigned long size, paddr, vaddr;
168 
169 		if (index >= m68k_realnum_memory) {
170 			printk( KERN_ERR DEVICE_NAME
171 				": no such entry in z2ram_map\n" );
172 		        goto err_out;
173 		}
174 
175 		paddr = m68k_memory[index].addr;
176 		size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
177 
178 #ifdef __powerpc__
179 		/* FIXME: ioremap doesn't build correct memory tables. */
180 		{
181 			vfree(vmalloc (size));
182 		}
183 
184 		vaddr = (unsigned long) __ioremap (paddr, size,
185 						   _PAGE_WRITETHRU);
186 
187 #else
188 		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
189 #endif
190 		z2ram_map =
191 			kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
192 				GFP_KERNEL);
193 		if ( z2ram_map == NULL )
194 		{
195 		    printk( KERN_ERR DEVICE_NAME
196 			": cannot get mem for z2ram_map\n" );
197 		    goto err_out;
198 		}
199 
200 		while (size) {
201 			z2ram_map[ z2ram_size++ ] = vaddr;
202 			size -= Z2RAM_CHUNKSIZE;
203 			vaddr += Z2RAM_CHUNKSIZE;
204 			list_count++;
205 		}
206 
207 		if ( z2ram_size != 0 )
208 		    printk( KERN_INFO DEVICE_NAME
209 			": using %iK List Entry %d Memory\n",
210 			list_count * Z2RAM_CHUNK1024, index );
211 	} else
212 
213 	switch ( device )
214 	{
215 	    case Z2MINOR_COMBINED:
216 
217 		z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
218 		if ( z2ram_map == NULL )
219 		{
220 		    printk( KERN_ERR DEVICE_NAME
221 			": cannot get mem for z2ram_map\n" );
222 		    goto err_out;
223 		}
224 
225 		get_z2ram();
226 		get_chipram();
227 
228 		if ( z2ram_size != 0 )
229 		    printk( KERN_INFO DEVICE_NAME
230 			": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
231 			z2_count * Z2RAM_CHUNK1024,
232 			chip_count * Z2RAM_CHUNK1024,
233 			( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
234 
235 	    break;
236 
237     	    case Z2MINOR_Z2ONLY:
238 		z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
239 		if ( z2ram_map == NULL )
240 		{
241 		    printk( KERN_ERR DEVICE_NAME
242 			": cannot get mem for z2ram_map\n" );
243 		    goto err_out;
244 		}
245 
246 		get_z2ram();
247 
248 		if ( z2ram_size != 0 )
249 		    printk( KERN_INFO DEVICE_NAME
250 			": using %iK of Zorro II RAM\n",
251 			z2_count * Z2RAM_CHUNK1024 );
252 
253 	    break;
254 
255 	    case Z2MINOR_CHIPONLY:
256 		z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
257 		if ( z2ram_map == NULL )
258 		{
259 		    printk( KERN_ERR DEVICE_NAME
260 			": cannot get mem for z2ram_map\n" );
261 		    goto err_out;
262 		}
263 
264 		get_chipram();
265 
266 		if ( z2ram_size != 0 )
267 		    printk( KERN_INFO DEVICE_NAME
268 			": using %iK Chip RAM\n",
269 			chip_count * Z2RAM_CHUNK1024 );
270 
271 	    break;
272 
273 	    default:
274 		rc = -ENODEV;
275 		goto err_out;
276 
277 	    break;
278 	}
279 
280 	if ( z2ram_size == 0 )
281 	{
282 	    printk( KERN_NOTICE DEVICE_NAME
283 		": no unused ZII/Chip RAM found\n" );
284 	    goto err_out_kfree;
285 	}
286 
287 	current_device = device;
288 	z2ram_size <<= Z2RAM_CHUNKSHIFT;
289 	set_capacity(z2ram_gendisk, z2ram_size >> 9);
290     }
291 
292     return 0;
293 
294 err_out_kfree:
295     kfree(z2ram_map);
296 err_out:
297     return rc;
298 }
299 
300 static int
301 z2_release(struct gendisk *disk, fmode_t mode)
302 {
303     if ( current_device == -1 )
304 	return 0;
305 
306     /*
307      * FIXME: unmap memory
308      */
309 
310     return 0;
311 }
312 
313 static struct block_device_operations z2_fops =
314 {
315 	.owner		= THIS_MODULE,
316 	.open		= z2_open,
317 	.release	= z2_release,
318 };
319 
320 static struct kobject *z2_find(dev_t dev, int *part, void *data)
321 {
322 	*part = 0;
323 	return get_disk(z2ram_gendisk);
324 }
325 
326 static struct request_queue *z2_queue;
327 
328 static int __init
329 z2_init(void)
330 {
331     int ret;
332 
333     if (!MACH_IS_AMIGA)
334 	return -ENODEV;
335 
336     ret = -EBUSY;
337     if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
338 	goto err;
339 
340     ret = -ENOMEM;
341     z2ram_gendisk = alloc_disk(1);
342     if (!z2ram_gendisk)
343 	goto out_disk;
344 
345     z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
346     if (!z2_queue)
347 	goto out_queue;
348 
349     z2ram_gendisk->major = Z2RAM_MAJOR;
350     z2ram_gendisk->first_minor = 0;
351     z2ram_gendisk->fops = &z2_fops;
352     sprintf(z2ram_gendisk->disk_name, "z2ram");
353 
354     z2ram_gendisk->queue = z2_queue;
355     add_disk(z2ram_gendisk);
356     blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
357 				z2_find, NULL, NULL);
358 
359     return 0;
360 
361 out_queue:
362     put_disk(z2ram_gendisk);
363 out_disk:
364     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
365 err:
366     return ret;
367 }
368 
369 static void __exit z2_exit(void)
370 {
371     int i, j;
372     blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), 256);
373     unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
374     del_gendisk(z2ram_gendisk);
375     put_disk(z2ram_gendisk);
376     blk_cleanup_queue(z2_queue);
377 
378     if ( current_device != -1 )
379     {
380 	i = 0;
381 
382 	for ( j = 0 ; j < z2_count; j++ )
383 	{
384 	    set_bit( i++, zorro_unused_z2ram );
385 	}
386 
387 	for ( j = 0 ; j < chip_count; j++ )
388 	{
389 	    if ( z2ram_map[ i ] )
390 	    {
391 		amiga_chip_free( (void *) z2ram_map[ i++ ] );
392 	    }
393 	}
394 
395 	if ( z2ram_map != NULL )
396 	{
397 	    kfree( z2ram_map );
398 	}
399     }
400 
401     return;
402 }
403 
404 module_init(z2_init);
405 module_exit(z2_exit);
406 MODULE_LICENSE("GPL");
407