1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Device driver for the SYMBIOS/LSILOGIC 53C8XX and 53C1010 family
4 * of PCI-SCSI IO processors.
5 *
6 * Copyright (C) 1999-2001  Gerard Roudier <groudier@free.fr>
7 *
8 * This driver is derived from the Linux sym53c8xx driver.
9 * Copyright (C) 1998-2000  Gerard Roudier
10 *
11 * The sym53c8xx driver is derived from the ncr53c8xx driver that had been
12 * a port of the FreeBSD ncr driver to Linux-1.2.13.
13 *
14 * The original ncr driver has been written for 386bsd and FreeBSD by
15 *         Wolfgang Stanglmeier        <wolf@cologne.de>
16 *         Stefan Esser                <se@mi.Uni-Koeln.de>
17 * Copyright (C) 1994  Wolfgang Stanglmeier
18 *
19 * Other major contributions:
20 *
21 * NVRAM detection and reading.
22 * Copyright (C) 1997 Richard Waltham <dormouse@farsrobt.demon.co.uk>
23 *
24 *-----------------------------------------------------------------------------
25 */
26
27#include "sym_glue.h"
28#include "sym_nvram.h"
29
30#ifdef	SYM_CONF_DEBUG_NVRAM
31static u_char Tekram_boot_delay[7] = {3, 5, 10, 20, 30, 60, 120};
32#endif
33
34/*
35 *  Get host setup from NVRAM.
36 */
37void sym_nvram_setup_host(struct Scsi_Host *shost, struct sym_hcb *np, struct sym_nvram *nvram)
38{
39	/*
40	 *  Get parity checking, host ID, verbose mode
41	 *  and miscellaneous host flags from NVRAM.
42	 */
43	switch (nvram->type) {
44	case SYM_SYMBIOS_NVRAM:
45		if (!(nvram->data.Symbios.flags & SYMBIOS_PARITY_ENABLE))
46			np->rv_scntl0  &= ~0x0a;
47		np->myaddr = nvram->data.Symbios.host_id & 0x0f;
48		if (nvram->data.Symbios.flags & SYMBIOS_VERBOSE_MSGS)
49			np->verbose += 1;
50		if (nvram->data.Symbios.flags1 & SYMBIOS_SCAN_HI_LO)
51			shost->reverse_ordering = 1;
52		if (nvram->data.Symbios.flags2 & SYMBIOS_AVOID_BUS_RESET)
53			np->usrflags |= SYM_AVOID_BUS_RESET;
54		break;
55	case SYM_TEKRAM_NVRAM:
56		np->myaddr = nvram->data.Tekram.host_id & 0x0f;
57		break;
58#ifdef CONFIG_PARISC
59	case SYM_PARISC_PDC:
60		if (nvram->data.parisc.host_id != -1)
61			np->myaddr = nvram->data.parisc.host_id;
62		if (nvram->data.parisc.factor != -1)
63			np->minsync = nvram->data.parisc.factor;
64		if (nvram->data.parisc.width != -1)
65			np->maxwide = nvram->data.parisc.width;
66		switch (nvram->data.parisc.mode) {
67			case 0: np->scsi_mode = SMODE_SE; break;
68			case 1: np->scsi_mode = SMODE_HVD; break;
69			case 2: np->scsi_mode = SMODE_LVD; break;
70			default: break;
71		}
72#endif
73	default:
74		break;
75	}
76}
77
78/*
79 *  Get target set-up from Symbios format NVRAM.
80 */
81static void
82sym_Symbios_setup_target(struct sym_tcb *tp, int target, Symbios_nvram *nvram)
83{
84	Symbios_target *tn = &nvram->target[target];
85
86	if (!(tn->flags & SYMBIOS_QUEUE_TAGS_ENABLED))
87		tp->usrtags = 0;
88	if (!(tn->flags & SYMBIOS_DISCONNECT_ENABLE))
89		tp->usrflags &= ~SYM_DISC_ENABLED;
90	if (!(tn->flags & SYMBIOS_SCAN_AT_BOOT_TIME))
91		tp->usrflags |= SYM_SCAN_BOOT_DISABLED;
92	if (!(tn->flags & SYMBIOS_SCAN_LUNS))
93		tp->usrflags |= SYM_SCAN_LUNS_DISABLED;
94	tp->usr_period = (tn->sync_period + 3) / 4;
95	tp->usr_width = (tn->bus_width == 0x8) ? 0 : 1;
96}
97
98static const unsigned char Tekram_sync[16] = {
99	25, 31, 37, 43, 50, 62, 75, 125, 12, 15, 18, 21, 6, 7, 9, 10
100};
101
102/*
103 *  Get target set-up from Tekram format NVRAM.
104 */
105static void
106sym_Tekram_setup_target(struct sym_tcb *tp, int target, Tekram_nvram *nvram)
107{
108	struct Tekram_target *tn = &nvram->target[target];
109
110	if (tn->flags & TEKRAM_TAGGED_COMMANDS) {
111		tp->usrtags = 2 << nvram->max_tags_index;
112	}
113
114	if (tn->flags & TEKRAM_DISCONNECT_ENABLE)
115		tp->usrflags |= SYM_DISC_ENABLED;
116
117	if (tn->flags & TEKRAM_SYNC_NEGO)
118		tp->usr_period = Tekram_sync[tn->sync_index & 0xf];
119	tp->usr_width = (tn->flags & TEKRAM_WIDE_NEGO) ? 1 : 0;
120}
121
122/*
123 *  Get target setup from NVRAM.
124 */
125void sym_nvram_setup_target(struct sym_tcb *tp, int target, struct sym_nvram *nvp)
126{
127	switch (nvp->type) {
128	case SYM_SYMBIOS_NVRAM:
129		sym_Symbios_setup_target(tp, target, &nvp->data.Symbios);
130		break;
131	case SYM_TEKRAM_NVRAM:
132		sym_Tekram_setup_target(tp, target, &nvp->data.Tekram);
133		break;
134	default:
135		break;
136	}
137}
138
139#ifdef	SYM_CONF_DEBUG_NVRAM
140/*
141 *  Dump Symbios format NVRAM for debugging purpose.
142 */
143static void sym_display_Symbios_nvram(struct sym_device *np, Symbios_nvram *nvram)
144{
145	int i;
146
147	/* display Symbios nvram host data */
148	printf("%s: HOST ID=%d%s%s%s%s%s%s\n",
149		sym_name(np), nvram->host_id & 0x0f,
150		(nvram->flags  & SYMBIOS_SCAM_ENABLE)	? " SCAM"	:"",
151		(nvram->flags  & SYMBIOS_PARITY_ENABLE)	? " PARITY"	:"",
152		(nvram->flags  & SYMBIOS_VERBOSE_MSGS)	? " VERBOSE"	:"",
153		(nvram->flags  & SYMBIOS_CHS_MAPPING)	? " CHS_ALT"	:"",
154		(nvram->flags2 & SYMBIOS_AVOID_BUS_RESET)?" NO_RESET"	:"",
155		(nvram->flags1 & SYMBIOS_SCAN_HI_LO)	? " HI_LO"	:"");
156
157	/* display Symbios nvram drive data */
158	for (i = 0 ; i < 15 ; i++) {
159		struct Symbios_target *tn = &nvram->target[i];
160		printf("%s-%d:%s%s%s%s WIDTH=%d SYNC=%d TMO=%d\n",
161		sym_name(np), i,
162		(tn->flags & SYMBIOS_DISCONNECT_ENABLE)	? " DISC"	: "",
163		(tn->flags & SYMBIOS_SCAN_AT_BOOT_TIME)	? " SCAN_BOOT"	: "",
164		(tn->flags & SYMBIOS_SCAN_LUNS)		? " SCAN_LUNS"	: "",
165		(tn->flags & SYMBIOS_QUEUE_TAGS_ENABLED)? " TCQ"	: "",
166		tn->bus_width,
167		tn->sync_period / 4,
168		tn->timeout);
169	}
170}
171
172/*
173 *  Dump TEKRAM format NVRAM for debugging purpose.
174 */
175static void sym_display_Tekram_nvram(struct sym_device *np, Tekram_nvram *nvram)
176{
177	int i, tags, boot_delay;
178	char *rem;
179
180	/* display Tekram nvram host data */
181	tags = 2 << nvram->max_tags_index;
182	boot_delay = 0;
183	if (nvram->boot_delay_index < 6)
184		boot_delay = Tekram_boot_delay[nvram->boot_delay_index];
185	switch ((nvram->flags & TEKRAM_REMOVABLE_FLAGS) >> 6) {
186	default:
187	case 0:	rem = "";			break;
188	case 1: rem = " REMOVABLE=boot device";	break;
189	case 2: rem = " REMOVABLE=all";		break;
190	}
191
192	printf("%s: HOST ID=%d%s%s%s%s%s%s%s%s%s BOOT DELAY=%d tags=%d\n",
193		sym_name(np), nvram->host_id & 0x0f,
194		(nvram->flags1 & SYMBIOS_SCAM_ENABLE)	? " SCAM"	:"",
195		(nvram->flags & TEKRAM_MORE_THAN_2_DRIVES) ? " >2DRIVES":"",
196		(nvram->flags & TEKRAM_DRIVES_SUP_1GB)	? " >1GB"	:"",
197		(nvram->flags & TEKRAM_RESET_ON_POWER_ON) ? " RESET"	:"",
198		(nvram->flags & TEKRAM_ACTIVE_NEGATION)	? " ACT_NEG"	:"",
199		(nvram->flags & TEKRAM_IMMEDIATE_SEEK)	? " IMM_SEEK"	:"",
200		(nvram->flags & TEKRAM_SCAN_LUNS)	? " SCAN_LUNS"	:"",
201		(nvram->flags1 & TEKRAM_F2_F6_ENABLED)	? " F2_F6"	:"",
202		rem, boot_delay, tags);
203
204	/* display Tekram nvram drive data */
205	for (i = 0; i <= 15; i++) {
206		int sync, j;
207		struct Tekram_target *tn = &nvram->target[i];
208		j = tn->sync_index & 0xf;
209		sync = Tekram_sync[j];
210		printf("%s-%d:%s%s%s%s%s%s PERIOD=%d\n",
211		sym_name(np), i,
212		(tn->flags & TEKRAM_PARITY_CHECK)	? " PARITY"	: "",
213		(tn->flags & TEKRAM_SYNC_NEGO)		? " SYNC"	: "",
214		(tn->flags & TEKRAM_DISCONNECT_ENABLE)	? " DISC"	: "",
215		(tn->flags & TEKRAM_START_CMD)		? " START"	: "",
216		(tn->flags & TEKRAM_TAGGED_COMMANDS)	? " TCQ"	: "",
217		(tn->flags & TEKRAM_WIDE_NEGO)		? " WIDE"	: "",
218		sync);
219	}
220}
221#else
222static void sym_display_Symbios_nvram(struct sym_device *np, Symbios_nvram *nvram) { (void)np; (void)nvram; }
223static void sym_display_Tekram_nvram(struct sym_device *np, Tekram_nvram *nvram) { (void)np; (void)nvram; }
224#endif	/* SYM_CONF_DEBUG_NVRAM */
225
226
227/*
228 *  24C16 EEPROM reading.
229 *
230 *  GPIO0 - data in/data out
231 *  GPIO1 - clock
232 *  Symbios NVRAM wiring now also used by Tekram.
233 */
234
235#define SET_BIT 0
236#define CLR_BIT 1
237#define SET_CLK 2
238#define CLR_CLK 3
239
240/*
241 *  Set/clear data/clock bit in GPIO0
242 */
243static void S24C16_set_bit(struct sym_device *np, u_char write_bit, u_char *gpreg,
244			  int bit_mode)
245{
246	udelay(5);
247	switch (bit_mode) {
248	case SET_BIT:
249		*gpreg |= write_bit;
250		break;
251	case CLR_BIT:
252		*gpreg &= 0xfe;
253		break;
254	case SET_CLK:
255		*gpreg |= 0x02;
256		break;
257	case CLR_CLK:
258		*gpreg &= 0xfd;
259		break;
260
261	}
262	OUTB(np, nc_gpreg, *gpreg);
263	INB(np, nc_mbox1);
264	udelay(5);
265}
266
267/*
268 *  Send START condition to NVRAM to wake it up.
269 */
270static void S24C16_start(struct sym_device *np, u_char *gpreg)
271{
272	S24C16_set_bit(np, 1, gpreg, SET_BIT);
273	S24C16_set_bit(np, 0, gpreg, SET_CLK);
274	S24C16_set_bit(np, 0, gpreg, CLR_BIT);
275	S24C16_set_bit(np, 0, gpreg, CLR_CLK);
276}
277
278/*
279 *  Send STOP condition to NVRAM - puts NVRAM to sleep... ZZzzzz!!
280 */
281static void S24C16_stop(struct sym_device *np, u_char *gpreg)
282{
283	S24C16_set_bit(np, 0, gpreg, SET_CLK);
284	S24C16_set_bit(np, 1, gpreg, SET_BIT);
285}
286
287/*
288 *  Read or write a bit to the NVRAM,
289 *  read if GPIO0 input else write if GPIO0 output
290 */
291static void S24C16_do_bit(struct sym_device *np, u_char *read_bit, u_char write_bit,
292			 u_char *gpreg)
293{
294	S24C16_set_bit(np, write_bit, gpreg, SET_BIT);
295	S24C16_set_bit(np, 0, gpreg, SET_CLK);
296	if (read_bit)
297		*read_bit = INB(np, nc_gpreg);
298	S24C16_set_bit(np, 0, gpreg, CLR_CLK);
299	S24C16_set_bit(np, 0, gpreg, CLR_BIT);
300}
301
302/*
303 *  Output an ACK to the NVRAM after reading,
304 *  change GPIO0 to output and when done back to an input
305 */
306static void S24C16_write_ack(struct sym_device *np, u_char write_bit, u_char *gpreg,
307			    u_char *gpcntl)
308{
309	OUTB(np, nc_gpcntl, *gpcntl & 0xfe);
310	S24C16_do_bit(np, NULL, write_bit, gpreg);
311	OUTB(np, nc_gpcntl, *gpcntl);
312}
313
314/*
315 *  Input an ACK from NVRAM after writing,
316 *  change GPIO0 to input and when done back to an output
317 */
318static void S24C16_read_ack(struct sym_device *np, u_char *read_bit, u_char *gpreg,
319			   u_char *gpcntl)
320{
321	OUTB(np, nc_gpcntl, *gpcntl | 0x01);
322	S24C16_do_bit(np, read_bit, 1, gpreg);
323	OUTB(np, nc_gpcntl, *gpcntl);
324}
325
326/*
327 *  WRITE a byte to the NVRAM and then get an ACK to see it was accepted OK,
328 *  GPIO0 must already be set as an output
329 */
330static void S24C16_write_byte(struct sym_device *np, u_char *ack_data, u_char write_data,
331			     u_char *gpreg, u_char *gpcntl)
332{
333	int x;
334
335	for (x = 0; x < 8; x++)
336		S24C16_do_bit(np, NULL, (write_data >> (7 - x)) & 0x01, gpreg);
337
338	S24C16_read_ack(np, ack_data, gpreg, gpcntl);
339}
340
341/*
342 *  READ a byte from the NVRAM and then send an ACK to say we have got it,
343 *  GPIO0 must already be set as an input
344 */
345static void S24C16_read_byte(struct sym_device *np, u_char *read_data, u_char ack_data,
346			    u_char *gpreg, u_char *gpcntl)
347{
348	int x;
349	u_char read_bit;
350
351	*read_data = 0;
352	for (x = 0; x < 8; x++) {
353		S24C16_do_bit(np, &read_bit, 1, gpreg);
354		*read_data |= ((read_bit & 0x01) << (7 - x));
355	}
356
357	S24C16_write_ack(np, ack_data, gpreg, gpcntl);
358}
359
360#ifdef SYM_CONF_NVRAM_WRITE_SUPPORT
361/*
362 *  Write 'len' bytes starting at 'offset'.
363 */
364static int sym_write_S24C16_nvram(struct sym_device *np, int offset,
365		u_char *data, int len)
366{
367	u_char	gpcntl, gpreg;
368	u_char	old_gpcntl, old_gpreg;
369	u_char	ack_data;
370	int	x;
371
372	/* save current state of GPCNTL and GPREG */
373	old_gpreg	= INB(np, nc_gpreg);
374	old_gpcntl	= INB(np, nc_gpcntl);
375	gpcntl		= old_gpcntl & 0x1c;
376
377	/* set up GPREG & GPCNTL to set GPIO0 and GPIO1 in to known state */
378	OUTB(np, nc_gpreg,  old_gpreg);
379	OUTB(np, nc_gpcntl, gpcntl);
380
381	/* this is to set NVRAM into a known state with GPIO0/1 both low */
382	gpreg = old_gpreg;
383	S24C16_set_bit(np, 0, &gpreg, CLR_CLK);
384	S24C16_set_bit(np, 0, &gpreg, CLR_BIT);
385
386	/* now set NVRAM inactive with GPIO0/1 both high */
387	S24C16_stop(np, &gpreg);
388
389	/* NVRAM has to be written in segments of 16 bytes */
390	for (x = 0; x < len ; x += 16) {
391		do {
392			S24C16_start(np, &gpreg);
393			S24C16_write_byte(np, &ack_data,
394					  0xa0 | (((offset+x) >> 7) & 0x0e),
395					  &gpreg, &gpcntl);
396		} while (ack_data & 0x01);
397
398		S24C16_write_byte(np, &ack_data, (offset+x) & 0xff,
399				  &gpreg, &gpcntl);
400
401		for (y = 0; y < 16; y++)
402			S24C16_write_byte(np, &ack_data, data[x+y],
403					  &gpreg, &gpcntl);
404		S24C16_stop(np, &gpreg);
405	}
406
407	/* return GPIO0/1 to original states after having accessed NVRAM */
408	OUTB(np, nc_gpcntl, old_gpcntl);
409	OUTB(np, nc_gpreg,  old_gpreg);
410
411	return 0;
412}
413#endif /* SYM_CONF_NVRAM_WRITE_SUPPORT */
414
415/*
416 *  Read 'len' bytes starting at 'offset'.
417 */
418static int sym_read_S24C16_nvram(struct sym_device *np, int offset, u_char *data, int len)
419{
420	u_char	gpcntl, gpreg;
421	u_char	old_gpcntl, old_gpreg;
422	u_char	ack_data;
423	int	retv = 1;
424	int	x;
425
426	/* save current state of GPCNTL and GPREG */
427	old_gpreg	= INB(np, nc_gpreg);
428	old_gpcntl	= INB(np, nc_gpcntl);
429	gpcntl		= old_gpcntl & 0x1c;
430
431	/* set up GPREG & GPCNTL to set GPIO0 and GPIO1 in to known state */
432	OUTB(np, nc_gpreg,  old_gpreg);
433	OUTB(np, nc_gpcntl, gpcntl);
434
435	/* this is to set NVRAM into a known state with GPIO0/1 both low */
436	gpreg = old_gpreg;
437	S24C16_set_bit(np, 0, &gpreg, CLR_CLK);
438	S24C16_set_bit(np, 0, &gpreg, CLR_BIT);
439
440	/* now set NVRAM inactive with GPIO0/1 both high */
441	S24C16_stop(np, &gpreg);
442
443	/* activate NVRAM */
444	S24C16_start(np, &gpreg);
445
446	/* write device code and random address MSB */
447	S24C16_write_byte(np, &ack_data,
448		0xa0 | ((offset >> 7) & 0x0e), &gpreg, &gpcntl);
449	if (ack_data & 0x01)
450		goto out;
451
452	/* write random address LSB */
453	S24C16_write_byte(np, &ack_data,
454		offset & 0xff, &gpreg, &gpcntl);
455	if (ack_data & 0x01)
456		goto out;
457
458	/* regenerate START state to set up for reading */
459	S24C16_start(np, &gpreg);
460
461	/* rewrite device code and address MSB with read bit set (lsb = 0x01) */
462	S24C16_write_byte(np, &ack_data,
463		0xa1 | ((offset >> 7) & 0x0e), &gpreg, &gpcntl);
464	if (ack_data & 0x01)
465		goto out;
466
467	/* now set up GPIO0 for inputting data */
468	gpcntl |= 0x01;
469	OUTB(np, nc_gpcntl, gpcntl);
470
471	/* input all requested data - only part of total NVRAM */
472	for (x = 0; x < len; x++)
473		S24C16_read_byte(np, &data[x], (x == (len-1)), &gpreg, &gpcntl);
474
475	/* finally put NVRAM back in inactive mode */
476	gpcntl &= 0xfe;
477	OUTB(np, nc_gpcntl, gpcntl);
478	S24C16_stop(np, &gpreg);
479	retv = 0;
480out:
481	/* return GPIO0/1 to original states after having accessed NVRAM */
482	OUTB(np, nc_gpcntl, old_gpcntl);
483	OUTB(np, nc_gpreg,  old_gpreg);
484
485	return retv;
486}
487
488#undef SET_BIT
489#undef CLR_BIT
490#undef SET_CLK
491#undef CLR_CLK
492
493/*
494 *  Try reading Symbios NVRAM.
495 *  Return 0 if OK.
496 */
497static int sym_read_Symbios_nvram(struct sym_device *np, Symbios_nvram *nvram)
498{
499	static u_char Symbios_trailer[6] = {0xfe, 0xfe, 0, 0, 0, 0};
500	u_char *data = (u_char *) nvram;
501	int len  = sizeof(*nvram);
502	u_short	csum;
503	int x;
504
505	/* probe the 24c16 and read the SYMBIOS 24c16 area */
506	if (sym_read_S24C16_nvram (np, SYMBIOS_NVRAM_ADDRESS, data, len))
507		return 1;
508
509	/* check valid NVRAM signature, verify byte count and checksum */
510	if (nvram->type != 0 ||
511	    memcmp(nvram->trailer, Symbios_trailer, 6) ||
512	    nvram->byte_count != len - 12)
513		return 1;
514
515	/* verify checksum */
516	for (x = 6, csum = 0; x < len - 6; x++)
517		csum += data[x];
518	if (csum != nvram->checksum)
519		return 1;
520
521	return 0;
522}
523
524/*
525 *  93C46 EEPROM reading.
526 *
527 *  GPIO0 - data in
528 *  GPIO1 - data out
529 *  GPIO2 - clock
530 *  GPIO4 - chip select
531 *
532 *  Used by Tekram.
533 */
534
535/*
536 *  Pulse clock bit in GPIO0
537 */
538static void T93C46_Clk(struct sym_device *np, u_char *gpreg)
539{
540	OUTB(np, nc_gpreg, *gpreg | 0x04);
541	INB(np, nc_mbox1);
542	udelay(2);
543	OUTB(np, nc_gpreg, *gpreg);
544}
545
546/*
547 *  Read bit from NVRAM
548 */
549static void T93C46_Read_Bit(struct sym_device *np, u_char *read_bit, u_char *gpreg)
550{
551	udelay(2);
552	T93C46_Clk(np, gpreg);
553	*read_bit = INB(np, nc_gpreg);
554}
555
556/*
557 *  Write bit to GPIO0
558 */
559static void T93C46_Write_Bit(struct sym_device *np, u_char write_bit, u_char *gpreg)
560{
561	if (write_bit & 0x01)
562		*gpreg |= 0x02;
563	else
564		*gpreg &= 0xfd;
565
566	*gpreg |= 0x10;
567
568	OUTB(np, nc_gpreg, *gpreg);
569	INB(np, nc_mbox1);
570	udelay(2);
571
572	T93C46_Clk(np, gpreg);
573}
574
575/*
576 *  Send STOP condition to NVRAM - puts NVRAM to sleep... ZZZzzz!!
577 */
578static void T93C46_Stop(struct sym_device *np, u_char *gpreg)
579{
580	*gpreg &= 0xef;
581	OUTB(np, nc_gpreg, *gpreg);
582	INB(np, nc_mbox1);
583	udelay(2);
584
585	T93C46_Clk(np, gpreg);
586}
587
588/*
589 *  Send read command and address to NVRAM
590 */
591static void T93C46_Send_Command(struct sym_device *np, u_short write_data,
592				u_char *read_bit, u_char *gpreg)
593{
594	int x;
595
596	/* send 9 bits, start bit (1), command (2), address (6)  */
597	for (x = 0; x < 9; x++)
598		T93C46_Write_Bit(np, (u_char) (write_data >> (8 - x)), gpreg);
599
600	*read_bit = INB(np, nc_gpreg);
601}
602
603/*
604 *  READ 2 bytes from the NVRAM
605 */
606static void T93C46_Read_Word(struct sym_device *np,
607		unsigned short *nvram_data, unsigned char *gpreg)
608{
609	int x;
610	u_char read_bit;
611
612	*nvram_data = 0;
613	for (x = 0; x < 16; x++) {
614		T93C46_Read_Bit(np, &read_bit, gpreg);
615
616		if (read_bit & 0x01)
617			*nvram_data |=  (0x01 << (15 - x));
618		else
619			*nvram_data &= ~(0x01 << (15 - x));
620	}
621}
622
623/*
624 *  Read Tekram NvRAM data.
625 */
626static int T93C46_Read_Data(struct sym_device *np, unsigned short *data,
627		int len, unsigned char *gpreg)
628{
629	int x;
630
631	for (x = 0; x < len; x++)  {
632		unsigned char read_bit;
633		/* output read command and address */
634		T93C46_Send_Command(np, 0x180 | x, &read_bit, gpreg);
635		if (read_bit & 0x01)
636			return 1; /* Bad */
637		T93C46_Read_Word(np, &data[x], gpreg);
638		T93C46_Stop(np, gpreg);
639	}
640
641	return 0;
642}
643
644/*
645 *  Try reading 93C46 Tekram NVRAM.
646 */
647static int sym_read_T93C46_nvram(struct sym_device *np, Tekram_nvram *nvram)
648{
649	u_char gpcntl, gpreg;
650	u_char old_gpcntl, old_gpreg;
651	int retv;
652
653	/* save current state of GPCNTL and GPREG */
654	old_gpreg	= INB(np, nc_gpreg);
655	old_gpcntl	= INB(np, nc_gpcntl);
656
657	/* set up GPREG & GPCNTL to set GPIO0/1/2/4 in to known state, 0 in,
658	   1/2/4 out */
659	gpreg = old_gpreg & 0xe9;
660	OUTB(np, nc_gpreg, gpreg);
661	gpcntl = (old_gpcntl & 0xe9) | 0x09;
662	OUTB(np, nc_gpcntl, gpcntl);
663
664	/* input all of NVRAM, 64 words */
665	retv = T93C46_Read_Data(np, (u_short *) nvram,
666				sizeof(*nvram) / sizeof(short), &gpreg);
667
668	/* return GPIO0/1/2/4 to original states after having accessed NVRAM */
669	OUTB(np, nc_gpcntl, old_gpcntl);
670	OUTB(np, nc_gpreg,  old_gpreg);
671
672	return retv;
673}
674
675/*
676 *  Try reading Tekram NVRAM.
677 *  Return 0 if OK.
678 */
679static int sym_read_Tekram_nvram (struct sym_device *np, Tekram_nvram *nvram)
680{
681	u_char *data = (u_char *) nvram;
682	int len = sizeof(*nvram);
683	u_short	csum;
684	int x;
685
686	switch (np->pdev->device) {
687	case PCI_DEVICE_ID_NCR_53C885:
688	case PCI_DEVICE_ID_NCR_53C895:
689	case PCI_DEVICE_ID_NCR_53C896:
690		x = sym_read_S24C16_nvram(np, TEKRAM_24C16_NVRAM_ADDRESS,
691					  data, len);
692		break;
693	case PCI_DEVICE_ID_NCR_53C875:
694		x = sym_read_S24C16_nvram(np, TEKRAM_24C16_NVRAM_ADDRESS,
695					  data, len);
696		if (!x)
697			break;
698		fallthrough;
699	default:
700		x = sym_read_T93C46_nvram(np, nvram);
701		break;
702	}
703	if (x)
704		return 1;
705
706	/* verify checksum */
707	for (x = 0, csum = 0; x < len - 1; x += 2)
708		csum += data[x] + (data[x+1] << 8);
709	if (csum != 0x1234)
710		return 1;
711
712	return 0;
713}
714
715#ifdef CONFIG_PARISC
716/*
717 * Host firmware (PDC) keeps a table for altering SCSI capabilities.
718 * Many newer machines export one channel of 53c896 chip as SE, 50-pin HD.
719 * Also used for Multi-initiator SCSI clusters to set the SCSI Initiator ID.
720 */
721static int sym_read_parisc_pdc(struct sym_device *np, struct pdc_initiator *pdc)
722{
723	struct hardware_path hwpath;
724	get_pci_node_path(np->pdev, &hwpath);
725	if (!pdc_get_initiator(&hwpath, pdc))
726		return 0;
727
728	return SYM_PARISC_PDC;
729}
730#else
731static inline int sym_read_parisc_pdc(struct sym_device *np,
732					struct pdc_initiator *x)
733{
734	return 0;
735}
736#endif
737
738/*
739 *  Try reading Symbios or Tekram NVRAM
740 */
741int sym_read_nvram(struct sym_device *np, struct sym_nvram *nvp)
742{
743	if (!sym_read_Symbios_nvram(np, &nvp->data.Symbios)) {
744		nvp->type = SYM_SYMBIOS_NVRAM;
745		sym_display_Symbios_nvram(np, &nvp->data.Symbios);
746	} else if (!sym_read_Tekram_nvram(np, &nvp->data.Tekram)) {
747		nvp->type = SYM_TEKRAM_NVRAM;
748		sym_display_Tekram_nvram(np, &nvp->data.Tekram);
749	} else {
750		nvp->type = sym_read_parisc_pdc(np, &nvp->data.parisc);
751	}
752	return nvp->type;
753}
754
755char *sym_nvram_type(struct sym_nvram *nvp)
756{
757	switch (nvp->type) {
758	case SYM_SYMBIOS_NVRAM:
759		return "Symbios NVRAM";
760	case SYM_TEKRAM_NVRAM:
761		return "Tekram NVRAM";
762	case SYM_PARISC_PDC:
763		return "PA-RISC Firmware";
764	default:
765		return "No NVRAM";
766	}
767}
768