summaryrefslogtreecommitdiff
path: root/drivers/scsi/mca_53c9x.c
blob: 998a8bbc1a4b748962f9787967bfebb647212883 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
/* mca_53c9x.c: Driver for the SCSI adapter found on NCR 35xx
 *  (and maybe some other) Microchannel machines
 *
 * Code taken mostly from Cyberstorm SCSI drivers
 *   Copyright (C) 1996 Jesper Skov (jskov@cygnus.co.uk)
 *
 * Hacked to work with the NCR MCA stuff by Tymm Twillman (tymm@computer.org)
 *
 * The CyberStorm SCSI driver (and this driver) is based on David S. Miller's
 *   ESP driver  * for the Sparc computers. 
 * 
 * Special thanks to Ken Stewart at Symbios (LSI) for helping with info on
 *  the 86C01.  I was on the brink of going ga-ga...
 *
 * Also thanks to Jesper Skov for helping me with info on how the Amiga
 *  does things...
 */

/*
 * This is currently only set up to use one 53c9x card at a time; it could be 
 *  changed fairly easily to detect/use more than one, but I'm not too sure how
 *  many cards that use the 53c9x on MCA systems there are (if, in fact, there
 *  are cards that use them, other than the one built into some NCR systems)...
 *  If anyone requests this, I'll throw it in, otherwise it's not worth the
 *  effort.
 */

/*
 * Info on the 86C01 MCA interface chip at the bottom, if you care enough to
 *  look.
 */

#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mca.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/mca-legacy.h>

#include "scsi.h"
#include <scsi/scsi_host.h>
#include "NCR53C9x.h"

#include <asm/dma.h>
#include <asm/irq.h>
#include <asm/mca_dma.h>
#include <asm/pgtable.h>

/*
 * From ibmmca.c (IBM scsi controller card driver) -- used for turning PS2 disk
 *  activity LED on and off
 */

#define PS2_SYS_CTR	0x92

/* Ports the ncr's 53c94 can be put at; indexed by pos register value */

#define MCA_53C9X_IO_PORTS {                             \
                         0x0000, 0x0240, 0x0340, 0x0400, \
	                 0x0420, 0x3240, 0x8240, 0xA240, \
	                }
			
/*
 * Supposedly there were some cards put together with the 'c9x and 86c01.  If
 *   they have different ID's from the ones on the 3500 series machines, 
 *   you can add them here and hopefully things will work out.
 */
			
#define MCA_53C9X_IDS {          \
                         0x7F4C, \
			 0x0000, \
                        }

static int  dma_bytes_sent(struct NCR_ESP *, int);
static int  dma_can_transfer(struct NCR_ESP *, Scsi_Cmnd *);
static void dma_dump_state(struct NCR_ESP *);
static void dma_init_read(struct NCR_ESP *, __u32, int);
static void dma_init_write(struct NCR_ESP *, __u32, int);
static void dma_ints_off(struct NCR_ESP *);
static void dma_ints_on(struct NCR_ESP *);
static int  dma_irq_p(struct NCR_ESP *);
static int  dma_ports_p(struct NCR_ESP *);
static void dma_setup(struct NCR_ESP *, __u32, int, int);
static void dma_led_on(struct NCR_ESP *);
static void dma_led_off(struct NCR_ESP *);

/* This is where all commands are put before they are trasfered to the 
 *  53c9x via PIO.
 */

static volatile unsigned char cmd_buffer[16];

/*
 * We keep the structure that is used to access the registers on the 53c9x
 *  here.
 */

static struct ESP_regs eregs;

/***************************************************************** Detection */
static int mca_esp_detect(struct scsi_host_template *tpnt)
{
	struct NCR_ESP *esp;
	static int io_port_by_pos[] = MCA_53C9X_IO_PORTS;
	int mca_53c9x_ids[] = MCA_53C9X_IDS;
	int *id_to_check = mca_53c9x_ids;
	int slot;
	int pos[3];
	unsigned int tmp_io_addr;
	unsigned char tmp_byte;


	if (!MCA_bus)
		return 0;

	while (*id_to_check) { 
		if ((slot = mca_find_adapter(*id_to_check, 0)) !=
		  MCA_NOTFOUND) 
		{
			esp = esp_allocate(tpnt, (void *) NULL);

			pos[0] = mca_read_stored_pos(slot, 2);
			pos[1] = mca_read_stored_pos(slot, 3);
			pos[2] = mca_read_stored_pos(slot, 4);

			esp->eregs = &eregs;

			/*
			 * IO port base is given in the first (non-ID) pos
			 *  register, like so:
			 *
			 *  Bits 3  2  1       IO base
			 * ----------------------------
			 *       0  0  0       <disabled>
			 *       0  0  1       0x0240
			 *       0  1  0       0x0340
			 *       0  1  1       0x0400
			 *       1  0  0       0x0420
			 *       1  0  1       0x3240
			 *       1  1  0       0x8240
			 *       1  1  1       0xA240
			 */

			tmp_io_addr =
			  io_port_by_pos[(pos[0] & 0x0E) >> 1];

			esp->eregs->io_addr = tmp_io_addr + 0x10;

      			if (esp->eregs->io_addr == 0x0000) { 
        			printk("Adapter is disabled.\n");
				break;
			}

			/*
			 * IRQ is specified in bits 4 and 5:
			 *
			 *  Bits  4  5        IRQ
			 * -----------------------
			 *        0  0         3
			 *        0  1         5
			 *        1  0         7
			 *        1  1         9
			 */

      			esp->irq = ((pos[0] & 0x30) >> 3) + 3;

			/*
			 * DMA channel is in the low 3 bits of the second
			 *  POS register
			 */

			esp->dma = pos[1] & 7;
			esp->slot = slot;

			if (request_irq(esp->irq, esp_intr, 0,
			 "NCR 53c9x SCSI", esp->ehost))
			{
				printk("Unable to request IRQ %d.\n", esp->irq);
				esp_deallocate(esp);
				scsi_unregister(esp->ehost);
				return 0;
			}

 			if (request_dma(esp->dma, "NCR 53c9x SCSI")) {
				printk("Unable to request DMA channel %d.\n",
				 esp->dma);
				free_irq(esp->irq, esp_intr);
				esp_deallocate(esp);
				scsi_unregister(esp->ehost);
				return 0;
			}

			request_region(tmp_io_addr, 32, "NCR 53c9x SCSI");

			/*
			 * 86C01 handles DMA, IO mode, from address
			 *  (base + 0x0a)
			 */

			mca_disable_dma(esp->dma);
			mca_set_dma_io(esp->dma, tmp_io_addr + 0x0a);
			mca_enable_dma(esp->dma);
 
			/* Tell the 86C01 to give us interrupts */

			tmp_byte = inb(tmp_io_addr + 0x02) | 0x40;
			outb(tmp_byte, tmp_io_addr + 0x02); 

			/*
			 * Scsi ID -- general purpose register, hi
			 *  2 bits; add 4 to this number to get the
			 *  ID
			 */

			esp->scsi_id = ((pos[2] & 0xC0) >> 6) + 4;

			/* Do command transfer with programmed I/O */

			esp->do_pio_cmds = 1;

			/* Required functions */

			esp->dma_bytes_sent = &dma_bytes_sent;
			esp->dma_can_transfer = &dma_can_transfer;
			esp->dma_dump_state = &dma_dump_state;
			esp->dma_init_read = &dma_init_read;
			esp->dma_init_write = &dma_init_write;
			esp->dma_ints_off = &dma_ints_off;
			esp->dma_ints_on = &dma_ints_on;
			esp->dma_irq_p = &dma_irq_p;
			esp->dma_ports_p = &dma_ports_p;
			esp->dma_setup = &dma_setup;

			/* Optional functions */

			esp->dma_barrier = NULL;
			esp->dma_drain = NULL;
			esp->dma_invalidate = NULL;
			esp->dma_irq_entry = NULL;
			esp->dma_irq_exit = NULL;
			esp->dma_led_on = dma_led_on;
			esp->dma_led_off = dma_led_off;
			esp->dma_poll = NULL;
			esp->dma_reset = NULL;

			/* Set the command buffer */

			esp->esp_command = (volatile unsigned char*)
			  cmd_buffer;
	 		esp->esp_command_dvma = isa_virt_to_bus(cmd_buffer);

			/* SCSI chip speed */

			esp->cfreq = 25000000;

			/* Differential SCSI? I think not. */

			esp->diff = 0;

			esp_initialize(esp);

      			printk(" Adapter found in slot %2d: io port 0x%x "
			  "irq %d dma channel %d\n", slot + 1, tmp_io_addr,
			   esp->irq, esp->dma);

			mca_set_adapter_name(slot, "NCR 53C9X SCSI Adapter");
			mca_mark_as_used(slot);

			break;
		}
    
		id_to_check++;
	}

	return esps_in_use;
}


/******************************************************************* Release */

static int mca_esp_release(struct Scsi_Host *host)
{
	struct NCR_ESP *esp = (struct NCR_ESP *)host->hostdata;
	unsigned char tmp_byte;

	esp_deallocate(esp);
	/*
	 * Tell the 86C01 to stop sending interrupts
	 */

	tmp_byte = inb(esp->eregs->io_addr - 0x0E);
	tmp_byte &= ~0x40;
	outb(tmp_byte, esp->eregs->io_addr - 0x0E);

	free_irq(esp->irq, esp_intr);
	free_dma(esp->dma);

	mca_mark_as_unused(esp->slot);

	return 0;
}

/************************************************************* DMA Functions */
static int dma_bytes_sent(struct NCR_ESP *esp, int fifo_count)
{
	/* Ask the 53c9x.  It knows. */

	return fifo_count;
}

static int dma_can_transfer(struct NCR_ESP *esp, Scsi_Cmnd *sp)
{
	/* 
	 * The MCA dma channels can only do up to 128K bytes at a time.
         *  (16 bit mode)
	 */

	unsigned long sz = sp->SCp.this_residual;
	if(sz > 0x20000)
		sz = 0x20000;
	return sz;
}

static void dma_dump_state(struct NCR_ESP *esp)
{
	/*
	 * Doesn't quite match up to the other drivers, but we do what we
	 *  can.
	 */

	ESPLOG(("esp%d: dma channel <%d>\n", esp->esp_id, esp->dma));
	ESPLOG(("bytes left to dma: %d\n", mca_get_dma_residue(esp->dma)));
}

static void dma_init_read(struct NCR_ESP *esp, __u32 addr, int length)
{
	unsigned long flags;


	save_flags(flags);
	cli();

	mca_disable_dma(esp->dma);
	mca_set_dma_mode(esp->dma, MCA_DMA_MODE_XFER | MCA_DMA_MODE_16 |
	  MCA_DMA_MODE_IO);
	mca_set_dma_addr(esp->dma, addr);
	mca_set_dma_count(esp->dma, length / 2); /* !!! */
	mca_enable_dma(esp->dma);

	restore_flags(flags);
}

static void dma_init_write(struct NCR_ESP *esp, __u32 addr, int length)
{
	unsigned long flags;


	save_flags(flags);
	cli();

	mca_disable_dma(esp->dma);
	mca_set_dma_mode(esp->dma, MCA_DMA_MODE_XFER | MCA_DMA_MODE_WRITE |
	  MCA_DMA_MODE_16 | MCA_DMA_MODE_IO);
	mca_set_dma_addr(esp->dma, addr);
	mca_set_dma_count(esp->dma, length / 2); /* !!! */
	mca_enable_dma(esp->dma);

	restore_flags(flags);
}

static void dma_ints_off(struct NCR_ESP *esp)
{
	/*
	 * Tell the 'C01 to shut up.  All interrupts are routed through it.
	 */

	outb(inb(esp->eregs->io_addr - 0x0E) & ~0x40,
	 esp->eregs->io_addr - 0x0E);
}

static void dma_ints_on(struct NCR_ESP *esp)
{
	/*
	 * Ok.  You can speak again.
	 */

	outb(inb(esp->eregs->io_addr - 0x0E) | 0x40,
	 esp->eregs->io_addr - 0x0E);
}

static int dma_irq_p(struct NCR_ESP *esp)
{
	/*
	 * DaveM says that this should return a "yes" if there is an interrupt
	 *  or a DMA error occurred.  I copied the Amiga driver's semantics,
	 *  though, because it seems to work and we can't really tell if
	 *  a DMA error happened.  This gives the "yes" if the scsi chip
	 *  is sending an interrupt and no DMA activity is taking place
	 */

	return (!(inb(esp->eregs->io_addr - 0x04) & 1) &&
	 !(inb(esp->eregs->io_addr - 0x04) & 2) ); 
}

static int dma_ports_p(struct NCR_ESP *esp)
{
	/*
	 * Check to see if interrupts are enabled on the 'C01 (in case abort
	 *  is entered multiple times, so we only do the abort once)
	 */

	return (inb(esp->eregs->io_addr - 0x0E) & 0x40) ? 1:0;
}

static void dma_setup(struct NCR_ESP *esp, __u32 addr, int count, int write)
{
	if(write){
		dma_init_write(esp, addr, count);
	} else {
		dma_init_read(esp, addr, count);
	}
}

/*
 * These will not play nicely with other disk controllers that try to use the
 *  disk active LED... but what can you do?  Don't answer that.
 *
 * Stolen shamelessly from ibmmca.c -- IBM Microchannel SCSI adapter driver
 *
 */

static void dma_led_on(struct NCR_ESP *esp)
{
	outb(inb(PS2_SYS_CTR) | 0xc0, PS2_SYS_CTR);
}

static void dma_led_off(struct NCR_ESP *esp)
{
	outb(inb(PS2_SYS_CTR) & 0x3f, PS2_SYS_CTR);
}

static struct scsi_host_template driver_template = {
	.proc_name		= "mca_53c9x",
	.name			= "NCR 53c9x SCSI",
	.detect			= mca_esp_detect,
	.slave_alloc		= esp_slave_alloc,
	.slave_destroy		= esp_slave_destroy,
	.release		= mca_esp_release,
	.queuecommand		= esp_queue,
	.eh_abort_handler	= esp_abort,
	.eh_bus_reset_handler	= esp_reset,
	.can_queue		= 7,
	.sg_tablesize		= SG_ALL,
	.cmd_per_lun		= 1,
	.unchecked_isa_dma	= 1,
	.use_clustering		= DISABLE_CLUSTERING
};


#include "scsi_module.c"

/*
 * OK, here's the goods I promised.  The NCR 86C01 is an MCA interface chip 
 *  that handles enabling/diabling IRQ, dma interfacing, IO port selection
 *  and other fun stuff.  It takes up 16 addresses, and the chip it is
 *  connnected to gets the following 16.  Registers are as follows:
 *
 * Offsets 0-1 : Card ID
 *
 * Offset    2 : Mode enable register --
 *                Bit    7 : Data Word width (1 = 16, 0 = 8)
 *		  Bit    6 : IRQ enable (1 = enabled)
 *                Bits 5,4 : IRQ select
 *                              0  0 : IRQ 3
 *			        0  1 : IRQ 5
 * 				1  0 : IRQ 7
 *  				1  1 : IRQ 9
 *                Bits 3-1 : Base Address
 *                           0  0  0 : <disabled>
 * 			     0  0  1 : 0x0240
 *    			     0  1  0 : 0x0340
 *     			     0  1  1 : 0x0400
 * 			     1  0  0 : 0x0420
 * 			     1  0  1 : 0x3240
 * 			     1  1  0 : 0x8240
 * 			     1  1  1 : 0xA240
 *		  Bit    0 : Card enable (1 = enabled)
 *
 * Offset    3 : DMA control register --
 *                Bit    7 : DMA enable (1 = enabled)
 *                Bits 6,5 : Preemt Count Select (transfers to complete after
 *                            'C01 has been preempted on MCA bus)
 *                              0  0 : 0
 *                              0  1 : 1
 *                              1  0 : 3
 *                              1  1 : 7
 *  (all these wacky numbers; I'm sure there's a reason somewhere)
 *                Bit    4 : Fairness enable (1 = fair bus priority)
 *                Bits 3-0 : Arbitration level (0-15 consecutive)
 * 
 * Offset    4 : General purpose register
 *                Bits 7-3 : User definable (here, 7,6 are SCSI ID)
 *                Bits 2-0 : reserved
 *
 * Offset   10 : DMA decode register (used for IO based DMA; also can do
 *                PIO through this port)
 *
 * Offset   12 : Status
 *                Bits 7-2 : reserved
 *                Bit    1 : DMA pending (1 = pending)
 *                Bit    0 : IRQ pending (0 = pending)
 *
 * Exciting, huh?  
 *
 */