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#include <linux/mutex.h>
37#include <linux/slab.h>
38
39#include <asm/setup.h>
40#include <asm/amigahw.h>
41#include <asm/pgtable.h>
42
43#include <linux/zorro.h>
44
45
46#define Z2MINOR_COMBINED      (0)
47#define Z2MINOR_Z2ONLY        (1)
48#define Z2MINOR_CHIPONLY      (2)
49#define Z2MINOR_MEMLIST1      (4)
50#define Z2MINOR_MEMLIST2      (5)
51#define Z2MINOR_MEMLIST3      (6)
52#define Z2MINOR_MEMLIST4      (7)
53#define Z2MINOR_COUNT         (8) /* Move this down when adding a new minor */
54
55#define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
56
57static DEFINE_MUTEX(z2ram_mutex);
58static u_long *z2ram_map    = NULL;
59static u_long z2ram_size    = 0;
60static int z2_count         = 0;
61static int chip_count       = 0;
62static int list_count       = 0;
63static int current_device   = -1;
64
65static DEFINE_SPINLOCK(z2ram_lock);
66
67static struct gendisk *z2ram_gendisk;
68
69static void do_z2_request(struct request_queue *q)
70{
71	struct request *req;
72
73	req = blk_fetch_request(q);
74	while (req) {
75		unsigned long start = blk_rq_pos(req) << 9;
76		unsigned long len  = blk_rq_cur_bytes(req);
77		int err = 0;
78
79		if (start + len > z2ram_size) {
80			pr_err(DEVICE_NAME ": bad access: block=%llu, "
81			       "count=%u\n",
82			       (unsigned long long)blk_rq_pos(req),
83			       blk_rq_cur_sectors(req));
84			err = -EIO;
85			goto done;
86		}
87		while (len) {
88			unsigned long addr = start & Z2RAM_CHUNKMASK;
89			unsigned long size = Z2RAM_CHUNKSIZE - addr;
90			void *buffer = bio_data(req->bio);
91
92			if (len < size)
93				size = len;
94			addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
95			if (rq_data_dir(req) == READ)
96				memcpy(buffer, (char *)addr, size);
97			else
98				memcpy((char *)addr, buffer, size);
99			start += size;
100			len -= size;
101		}
102	done:
103		if (!__blk_end_request_cur(req, err))
104			req = blk_fetch_request(q);
105	}
106}
107
108static void
109get_z2ram( void )
110{
111    int i;
112
113    for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
114    {
115	if ( test_bit( i, zorro_unused_z2ram ) )
116	{
117	    z2_count++;
118	    z2ram_map[z2ram_size++] = (unsigned long)ZTWO_VADDR(Z2RAM_START) +
119				      (i << Z2RAM_CHUNKSHIFT);
120	    clear_bit( i, zorro_unused_z2ram );
121	}
122    }
123
124    return;
125}
126
127static void
128get_chipram( void )
129{
130
131    while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
132    {
133	chip_count++;
134	z2ram_map[ z2ram_size ] =
135	    (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
136
137	if ( z2ram_map[ z2ram_size ] == 0 )
138	{
139	    break;
140	}
141
142	z2ram_size++;
143    }
144
145    return;
146}
147
148static int z2_open(struct block_device *bdev, fmode_t mode)
149{
150    int device;
151    int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
152	sizeof( z2ram_map[0] );
153    int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
154	sizeof( z2ram_map[0] );
155    int rc = -ENOMEM;
156
157    device = MINOR(bdev->bd_dev);
158
159    mutex_lock(&z2ram_mutex);
160    if ( current_device != -1 && current_device != device )
161    {
162	rc = -EBUSY;
163	goto err_out;
164    }
165
166    if ( current_device == -1 )
167    {
168	z2_count   = 0;
169	chip_count = 0;
170	list_count = 0;
171	z2ram_size = 0;
172
173	/* Use a specific list entry. */
174	if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
175		int index = device - Z2MINOR_MEMLIST1 + 1;
176		unsigned long size, paddr, vaddr;
177
178		if (index >= m68k_realnum_memory) {
179			printk( KERN_ERR DEVICE_NAME
180				": no such entry in z2ram_map\n" );
181		        goto err_out;
182		}
183
184		paddr = m68k_memory[index].addr;
185		size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
186
187#ifdef __powerpc__
188		/* FIXME: ioremap doesn't build correct memory tables. */
189		{
190			vfree(vmalloc (size));
191		}
192
193		vaddr = (unsigned long) __ioremap (paddr, size,
194						   _PAGE_WRITETHRU);
195
196#else
197		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
198#endif
199		z2ram_map =
200			kmalloc((size/Z2RAM_CHUNKSIZE)*sizeof(z2ram_map[0]),
201				GFP_KERNEL);
202		if ( z2ram_map == NULL )
203		{
204		    printk( KERN_ERR DEVICE_NAME
205			": cannot get mem for z2ram_map\n" );
206		    goto err_out;
207		}
208
209		while (size) {
210			z2ram_map[ z2ram_size++ ] = vaddr;
211			size -= Z2RAM_CHUNKSIZE;
212			vaddr += Z2RAM_CHUNKSIZE;
213			list_count++;
214		}
215
216		if ( z2ram_size != 0 )
217		    printk( KERN_INFO DEVICE_NAME
218			": using %iK List Entry %d Memory\n",
219			list_count * Z2RAM_CHUNK1024, index );
220	} else
221
222	switch ( device )
223	{
224	    case Z2MINOR_COMBINED:
225
226		z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
227		if ( z2ram_map == NULL )
228		{
229		    printk( KERN_ERR DEVICE_NAME
230			": cannot get mem for z2ram_map\n" );
231		    goto err_out;
232		}
233
234		get_z2ram();
235		get_chipram();
236
237		if ( z2ram_size != 0 )
238		    printk( KERN_INFO DEVICE_NAME
239			": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
240			z2_count * Z2RAM_CHUNK1024,
241			chip_count * Z2RAM_CHUNK1024,
242			( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
243
244	    break;
245
246    	    case Z2MINOR_Z2ONLY:
247		z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
248		if ( z2ram_map == NULL )
249		{
250		    printk( KERN_ERR DEVICE_NAME
251			": cannot get mem for z2ram_map\n" );
252		    goto err_out;
253		}
254
255		get_z2ram();
256
257		if ( z2ram_size != 0 )
258		    printk( KERN_INFO DEVICE_NAME
259			": using %iK of Zorro II RAM\n",
260			z2_count * Z2RAM_CHUNK1024 );
261
262	    break;
263
264	    case Z2MINOR_CHIPONLY:
265		z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
266		if ( z2ram_map == NULL )
267		{
268		    printk( KERN_ERR DEVICE_NAME
269			": cannot get mem for z2ram_map\n" );
270		    goto err_out;
271		}
272
273		get_chipram();
274
275		if ( z2ram_size != 0 )
276		    printk( KERN_INFO DEVICE_NAME
277			": using %iK Chip RAM\n",
278			chip_count * Z2RAM_CHUNK1024 );
279
280	    break;
281
282	    default:
283		rc = -ENODEV;
284		goto err_out;
285
286	    break;
287	}
288
289	if ( z2ram_size == 0 )
290	{
291	    printk( KERN_NOTICE DEVICE_NAME
292		": no unused ZII/Chip RAM found\n" );
293	    goto err_out_kfree;
294	}
295
296	current_device = device;
297	z2ram_size <<= Z2RAM_CHUNKSHIFT;
298	set_capacity(z2ram_gendisk, z2ram_size >> 9);
299    }
300
301    mutex_unlock(&z2ram_mutex);
302    return 0;
303
304err_out_kfree:
305    kfree(z2ram_map);
306err_out:
307    mutex_unlock(&z2ram_mutex);
308    return rc;
309}
310
311static void
312z2_release(struct gendisk *disk, fmode_t mode)
313{
314    mutex_lock(&z2ram_mutex);
315    if ( current_device == -1 ) {
316    	mutex_unlock(&z2ram_mutex);
317    	return;
318    }
319    mutex_unlock(&z2ram_mutex);
320    /*
321     * FIXME: unmap memory
322     */
323}
324
325static const struct block_device_operations z2_fops =
326{
327	.owner		= THIS_MODULE,
328	.open		= z2_open,
329	.release	= z2_release,
330};
331
332static struct kobject *z2_find(dev_t dev, int *part, void *data)
333{
334	*part = 0;
335	return get_disk(z2ram_gendisk);
336}
337
338static struct request_queue *z2_queue;
339
340static int __init
341z2_init(void)
342{
343    int ret;
344
345    if (!MACH_IS_AMIGA)
346	return -ENODEV;
347
348    ret = -EBUSY;
349    if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
350	goto err;
351
352    ret = -ENOMEM;
353    z2ram_gendisk = alloc_disk(1);
354    if (!z2ram_gendisk)
355	goto out_disk;
356
357    z2_queue = blk_init_queue(do_z2_request, &z2ram_lock);
358    if (!z2_queue)
359	goto out_queue;
360
361    z2ram_gendisk->major = Z2RAM_MAJOR;
362    z2ram_gendisk->first_minor = 0;
363    z2ram_gendisk->fops = &z2_fops;
364    sprintf(z2ram_gendisk->disk_name, "z2ram");
365
366    z2ram_gendisk->queue = z2_queue;
367    add_disk(z2ram_gendisk);
368    blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
369				z2_find, NULL, NULL);
370
371    return 0;
372
373out_queue:
374    put_disk(z2ram_gendisk);
375out_disk:
376    unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
377err:
378    return ret;
379}
380
381static void __exit z2_exit(void)
382{
383    int i, j;
384    blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT);
385    unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
386    del_gendisk(z2ram_gendisk);
387    put_disk(z2ram_gendisk);
388    blk_cleanup_queue(z2_queue);
389
390    if ( current_device != -1 )
391    {
392	i = 0;
393
394	for ( j = 0 ; j < z2_count; j++ )
395	{
396	    set_bit( i++, zorro_unused_z2ram );
397	}
398
399	for ( j = 0 ; j < chip_count; j++ )
400	{
401	    if ( z2ram_map[ i ] )
402	    {
403		amiga_chip_free( (void *) z2ram_map[ i++ ] );
404	    }
405	}
406
407	if ( z2ram_map != NULL )
408	{
409	    kfree( z2ram_map );
410	}
411    }
412
413    return;
414}
415
416module_init(z2_init);
417module_exit(z2_exit);
418MODULE_LICENSE("GPL");
419