xref: /linux/arch/powerpc/platforms/powermac/nvram.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1 /*
2  *  Copyright (C) 2002 Benjamin Herrenschmidt (benh@kernel.crashing.org)
3  *
4  *  This program is free software; you can redistribute it and/or
5  *  modify it under the terms of the GNU General Public License
6  *  as published by the Free Software Foundation; either version
7  *  2 of the License, or (at your option) any later version.
8  *
9  *  Todo: - add support for the OF persistent properties
10  */
11 #include <linux/config.h>
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/stddef.h>
15 #include <linux/string.h>
16 #include <linux/nvram.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/errno.h>
21 #include <linux/adb.h>
22 #include <linux/pmu.h>
23 #include <linux/bootmem.h>
24 #include <linux/completion.h>
25 #include <linux/spinlock.h>
26 #include <asm/sections.h>
27 #include <asm/io.h>
28 #include <asm/system.h>
29 #include <asm/prom.h>
30 #include <asm/machdep.h>
31 #include <asm/nvram.h>
32 
33 #define DEBUG
34 
35 #ifdef DEBUG
36 #define DBG(x...) printk(x)
37 #else
38 #define DBG(x...)
39 #endif
40 
41 #define NVRAM_SIZE		0x2000	/* 8kB of non-volatile RAM */
42 
43 #define CORE99_SIGNATURE	0x5a
44 #define CORE99_ADLER_START	0x14
45 
46 /* On Core99, nvram is either a sharp, a micron or an AMD flash */
47 #define SM_FLASH_STATUS_DONE	0x80
48 #define SM_FLASH_STATUS_ERR	0x38
49 
50 #define SM_FLASH_CMD_ERASE_CONFIRM	0xd0
51 #define SM_FLASH_CMD_ERASE_SETUP	0x20
52 #define SM_FLASH_CMD_RESET		0xff
53 #define SM_FLASH_CMD_WRITE_SETUP	0x40
54 #define SM_FLASH_CMD_CLEAR_STATUS	0x50
55 #define SM_FLASH_CMD_READ_STATUS	0x70
56 
57 /* CHRP NVRAM header */
58 struct chrp_header {
59   u8		signature;
60   u8		cksum;
61   u16		len;
62   char          name[12];
63   u8		data[0];
64 };
65 
66 struct core99_header {
67   struct chrp_header	hdr;
68   u32			adler;
69   u32			generation;
70   u32			reserved[2];
71 };
72 
73 /*
74  * Read and write the non-volatile RAM on PowerMacs and CHRP machines.
75  */
76 static int nvram_naddrs;
77 static volatile unsigned char __iomem *nvram_data;
78 static int is_core_99;
79 static int core99_bank = 0;
80 static int nvram_partitions[3];
81 // XXX Turn that into a sem
82 static DEFINE_SPINLOCK(nv_lock);
83 
84 extern int pmac_newworld;
85 extern int system_running;
86 
87 static int (*core99_write_bank)(int bank, u8* datas);
88 static int (*core99_erase_bank)(int bank);
89 
90 static char *nvram_image;
91 
92 
93 static unsigned char core99_nvram_read_byte(int addr)
94 {
95 	if (nvram_image == NULL)
96 		return 0xff;
97 	return nvram_image[addr];
98 }
99 
100 static void core99_nvram_write_byte(int addr, unsigned char val)
101 {
102 	if (nvram_image == NULL)
103 		return;
104 	nvram_image[addr] = val;
105 }
106 
107 static ssize_t core99_nvram_read(char *buf, size_t count, loff_t *index)
108 {
109 	int i;
110 
111 	if (nvram_image == NULL)
112 		return -ENODEV;
113 	if (*index > NVRAM_SIZE)
114 		return 0;
115 
116 	i = *index;
117 	if (i + count > NVRAM_SIZE)
118 		count = NVRAM_SIZE - i;
119 
120 	memcpy(buf, &nvram_image[i], count);
121 	*index = i + count;
122 	return count;
123 }
124 
125 static ssize_t core99_nvram_write(char *buf, size_t count, loff_t *index)
126 {
127 	int i;
128 
129 	if (nvram_image == NULL)
130 		return -ENODEV;
131 	if (*index > NVRAM_SIZE)
132 		return 0;
133 
134 	i = *index;
135 	if (i + count > NVRAM_SIZE)
136 		count = NVRAM_SIZE - i;
137 
138 	memcpy(&nvram_image[i], buf, count);
139 	*index = i + count;
140 	return count;
141 }
142 
143 static ssize_t core99_nvram_size(void)
144 {
145 	if (nvram_image == NULL)
146 		return -ENODEV;
147 	return NVRAM_SIZE;
148 }
149 
150 #ifdef CONFIG_PPC32
151 static volatile unsigned char __iomem *nvram_addr;
152 static int nvram_mult;
153 
154 static unsigned char direct_nvram_read_byte(int addr)
155 {
156 	return in_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult]);
157 }
158 
159 static void direct_nvram_write_byte(int addr, unsigned char val)
160 {
161 	out_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult], val);
162 }
163 
164 
165 static unsigned char indirect_nvram_read_byte(int addr)
166 {
167 	unsigned char val;
168 	unsigned long flags;
169 
170 	spin_lock_irqsave(&nv_lock, flags);
171 	out_8(nvram_addr, addr >> 5);
172 	val = in_8(&nvram_data[(addr & 0x1f) << 4]);
173 	spin_unlock_irqrestore(&nv_lock, flags);
174 
175 	return val;
176 }
177 
178 static void indirect_nvram_write_byte(int addr, unsigned char val)
179 {
180 	unsigned long flags;
181 
182 	spin_lock_irqsave(&nv_lock, flags);
183 	out_8(nvram_addr, addr >> 5);
184 	out_8(&nvram_data[(addr & 0x1f) << 4], val);
185 	spin_unlock_irqrestore(&nv_lock, flags);
186 }
187 
188 
189 #ifdef CONFIG_ADB_PMU
190 
191 static void pmu_nvram_complete(struct adb_request *req)
192 {
193 	if (req->arg)
194 		complete((struct completion *)req->arg);
195 }
196 
197 static unsigned char pmu_nvram_read_byte(int addr)
198 {
199 	struct adb_request req;
200 	DECLARE_COMPLETION(req_complete);
201 
202 	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
203 	if (pmu_request(&req, pmu_nvram_complete, 3, PMU_READ_NVRAM,
204 			(addr >> 8) & 0xff, addr & 0xff))
205 		return 0xff;
206 	if (system_state == SYSTEM_RUNNING)
207 		wait_for_completion(&req_complete);
208 	while (!req.complete)
209 		pmu_poll();
210 	return req.reply[0];
211 }
212 
213 static void pmu_nvram_write_byte(int addr, unsigned char val)
214 {
215 	struct adb_request req;
216 	DECLARE_COMPLETION(req_complete);
217 
218 	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
219 	if (pmu_request(&req, pmu_nvram_complete, 4, PMU_WRITE_NVRAM,
220 			(addr >> 8) & 0xff, addr & 0xff, val))
221 		return;
222 	if (system_state == SYSTEM_RUNNING)
223 		wait_for_completion(&req_complete);
224 	while (!req.complete)
225 		pmu_poll();
226 }
227 
228 #endif /* CONFIG_ADB_PMU */
229 #endif /* CONFIG_PPC32 */
230 
231 static u8 chrp_checksum(struct chrp_header* hdr)
232 {
233 	u8 *ptr;
234 	u16 sum = hdr->signature;
235 	for (ptr = (u8 *)&hdr->len; ptr < hdr->data; ptr++)
236 		sum += *ptr;
237 	while (sum > 0xFF)
238 		sum = (sum & 0xFF) + (sum>>8);
239 	return sum;
240 }
241 
242 static u32 core99_calc_adler(u8 *buffer)
243 {
244 	int cnt;
245 	u32 low, high;
246 
247    	buffer += CORE99_ADLER_START;
248 	low = 1;
249 	high = 0;
250 	for (cnt=0; cnt<(NVRAM_SIZE-CORE99_ADLER_START); cnt++) {
251 		if ((cnt % 5000) == 0) {
252 			high  %= 65521UL;
253 			high %= 65521UL;
254 		}
255 		low += buffer[cnt];
256 		high += low;
257 	}
258 	low  %= 65521UL;
259 	high %= 65521UL;
260 
261 	return (high << 16) | low;
262 }
263 
264 static u32 core99_check(u8* datas)
265 {
266 	struct core99_header* hdr99 = (struct core99_header*)datas;
267 
268 	if (hdr99->hdr.signature != CORE99_SIGNATURE) {
269 		DBG("Invalid signature\n");
270 		return 0;
271 	}
272 	if (hdr99->hdr.cksum != chrp_checksum(&hdr99->hdr)) {
273 		DBG("Invalid checksum\n");
274 		return 0;
275 	}
276 	if (hdr99->adler != core99_calc_adler(datas)) {
277 		DBG("Invalid adler\n");
278 		return 0;
279 	}
280 	return hdr99->generation;
281 }
282 
283 static int sm_erase_bank(int bank)
284 {
285 	int stat, i;
286 	unsigned long timeout;
287 
288 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
289 
290        	DBG("nvram: Sharp/Micron Erasing bank %d...\n", bank);
291 
292 	out_8(base, SM_FLASH_CMD_ERASE_SETUP);
293 	out_8(base, SM_FLASH_CMD_ERASE_CONFIRM);
294 	timeout = 0;
295 	do {
296 		if (++timeout > 1000000) {
297 			printk(KERN_ERR "nvram: Sharp/Micron flash erase timeout !\n");
298 			break;
299 		}
300 		out_8(base, SM_FLASH_CMD_READ_STATUS);
301 		stat = in_8(base);
302 	} while (!(stat & SM_FLASH_STATUS_DONE));
303 
304 	out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
305 	out_8(base, SM_FLASH_CMD_RESET);
306 
307 	for (i=0; i<NVRAM_SIZE; i++)
308 		if (base[i] != 0xff) {
309 			printk(KERN_ERR "nvram: Sharp/Micron flash erase failed !\n");
310 			return -ENXIO;
311 		}
312 	return 0;
313 }
314 
315 static int sm_write_bank(int bank, u8* datas)
316 {
317 	int i, stat = 0;
318 	unsigned long timeout;
319 
320 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
321 
322        	DBG("nvram: Sharp/Micron Writing bank %d...\n", bank);
323 
324 	for (i=0; i<NVRAM_SIZE; i++) {
325 		out_8(base+i, SM_FLASH_CMD_WRITE_SETUP);
326 		udelay(1);
327 		out_8(base+i, datas[i]);
328 		timeout = 0;
329 		do {
330 			if (++timeout > 1000000) {
331 				printk(KERN_ERR "nvram: Sharp/Micron flash write timeout !\n");
332 				break;
333 			}
334 			out_8(base, SM_FLASH_CMD_READ_STATUS);
335 			stat = in_8(base);
336 		} while (!(stat & SM_FLASH_STATUS_DONE));
337 		if (!(stat & SM_FLASH_STATUS_DONE))
338 			break;
339 	}
340 	out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
341 	out_8(base, SM_FLASH_CMD_RESET);
342 	for (i=0; i<NVRAM_SIZE; i++)
343 		if (base[i] != datas[i]) {
344 			printk(KERN_ERR "nvram: Sharp/Micron flash write failed !\n");
345 			return -ENXIO;
346 		}
347 	return 0;
348 }
349 
350 static int amd_erase_bank(int bank)
351 {
352 	int i, stat = 0;
353 	unsigned long timeout;
354 
355 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
356 
357        	DBG("nvram: AMD Erasing bank %d...\n", bank);
358 
359 	/* Unlock 1 */
360 	out_8(base+0x555, 0xaa);
361 	udelay(1);
362 	/* Unlock 2 */
363 	out_8(base+0x2aa, 0x55);
364 	udelay(1);
365 
366 	/* Sector-Erase */
367 	out_8(base+0x555, 0x80);
368 	udelay(1);
369 	out_8(base+0x555, 0xaa);
370 	udelay(1);
371 	out_8(base+0x2aa, 0x55);
372 	udelay(1);
373 	out_8(base, 0x30);
374 	udelay(1);
375 
376 	timeout = 0;
377 	do {
378 		if (++timeout > 1000000) {
379 			printk(KERN_ERR "nvram: AMD flash erase timeout !\n");
380 			break;
381 		}
382 		stat = in_8(base) ^ in_8(base);
383 	} while (stat != 0);
384 
385 	/* Reset */
386 	out_8(base, 0xf0);
387 	udelay(1);
388 
389 	for (i=0; i<NVRAM_SIZE; i++)
390 		if (base[i] != 0xff) {
391 			printk(KERN_ERR "nvram: AMD flash erase failed !\n");
392 			return -ENXIO;
393 		}
394 	return 0;
395 }
396 
397 static int amd_write_bank(int bank, u8* datas)
398 {
399 	int i, stat = 0;
400 	unsigned long timeout;
401 
402 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
403 
404        	DBG("nvram: AMD Writing bank %d...\n", bank);
405 
406 	for (i=0; i<NVRAM_SIZE; i++) {
407 		/* Unlock 1 */
408 		out_8(base+0x555, 0xaa);
409 		udelay(1);
410 		/* Unlock 2 */
411 		out_8(base+0x2aa, 0x55);
412 		udelay(1);
413 
414 		/* Write single word */
415 		out_8(base+0x555, 0xa0);
416 		udelay(1);
417 		out_8(base+i, datas[i]);
418 
419 		timeout = 0;
420 		do {
421 			if (++timeout > 1000000) {
422 				printk(KERN_ERR "nvram: AMD flash write timeout !\n");
423 				break;
424 			}
425 			stat = in_8(base) ^ in_8(base);
426 		} while (stat != 0);
427 		if (stat != 0)
428 			break;
429 	}
430 
431 	/* Reset */
432 	out_8(base, 0xf0);
433 	udelay(1);
434 
435 	for (i=0; i<NVRAM_SIZE; i++)
436 		if (base[i] != datas[i]) {
437 			printk(KERN_ERR "nvram: AMD flash write failed !\n");
438 			return -ENXIO;
439 		}
440 	return 0;
441 }
442 
443 static void __init lookup_partitions(void)
444 {
445 	u8 buffer[17];
446 	int i, offset;
447 	struct chrp_header* hdr;
448 
449 	if (pmac_newworld) {
450 		nvram_partitions[pmac_nvram_OF] = -1;
451 		nvram_partitions[pmac_nvram_XPRAM] = -1;
452 		nvram_partitions[pmac_nvram_NR] = -1;
453 		hdr = (struct chrp_header *)buffer;
454 
455 		offset = 0;
456 		buffer[16] = 0;
457 		do {
458 			for (i=0;i<16;i++)
459 				buffer[i] = ppc_md.nvram_read_val(offset+i);
460 			if (!strcmp(hdr->name, "common"))
461 				nvram_partitions[pmac_nvram_OF] = offset + 0x10;
462 			if (!strcmp(hdr->name, "APL,MacOS75")) {
463 				nvram_partitions[pmac_nvram_XPRAM] = offset + 0x10;
464 				nvram_partitions[pmac_nvram_NR] = offset + 0x110;
465 			}
466 			offset += (hdr->len * 0x10);
467 		} while(offset < NVRAM_SIZE);
468 	} else {
469 		nvram_partitions[pmac_nvram_OF] = 0x1800;
470 		nvram_partitions[pmac_nvram_XPRAM] = 0x1300;
471 		nvram_partitions[pmac_nvram_NR] = 0x1400;
472 	}
473 	DBG("nvram: OF partition at 0x%x\n", nvram_partitions[pmac_nvram_OF]);
474 	DBG("nvram: XP partition at 0x%x\n", nvram_partitions[pmac_nvram_XPRAM]);
475 	DBG("nvram: NR partition at 0x%x\n", nvram_partitions[pmac_nvram_NR]);
476 }
477 
478 static void core99_nvram_sync(void)
479 {
480 	struct core99_header* hdr99;
481 	unsigned long flags;
482 
483 	if (!is_core_99 || !nvram_data || !nvram_image)
484 		return;
485 
486 	spin_lock_irqsave(&nv_lock, flags);
487 	if (!memcmp(nvram_image, (u8*)nvram_data + core99_bank*NVRAM_SIZE,
488 		NVRAM_SIZE))
489 		goto bail;
490 
491 	DBG("Updating nvram...\n");
492 
493 	hdr99 = (struct core99_header*)nvram_image;
494 	hdr99->generation++;
495 	hdr99->hdr.signature = CORE99_SIGNATURE;
496 	hdr99->hdr.cksum = chrp_checksum(&hdr99->hdr);
497 	hdr99->adler = core99_calc_adler(nvram_image);
498 	core99_bank = core99_bank ? 0 : 1;
499 	if (core99_erase_bank)
500 		if (core99_erase_bank(core99_bank)) {
501 			printk("nvram: Error erasing bank %d\n", core99_bank);
502 			goto bail;
503 		}
504 	if (core99_write_bank)
505 		if (core99_write_bank(core99_bank, nvram_image))
506 			printk("nvram: Error writing bank %d\n", core99_bank);
507  bail:
508 	spin_unlock_irqrestore(&nv_lock, flags);
509 
510 #ifdef DEBUG
511        	mdelay(2000);
512 #endif
513 }
514 
515 static int __init core99_nvram_setup(struct device_node *dp, unsigned long addr)
516 {
517 	int i;
518 	u32 gen_bank0, gen_bank1;
519 
520 	if (nvram_naddrs < 1) {
521 		printk(KERN_ERR "nvram: no address\n");
522 		return -EINVAL;
523 	}
524 	nvram_image = alloc_bootmem(NVRAM_SIZE);
525 	if (nvram_image == NULL) {
526 		printk(KERN_ERR "nvram: can't allocate ram image\n");
527 		return -ENOMEM;
528 	}
529 	nvram_data = ioremap(addr, NVRAM_SIZE*2);
530 	nvram_naddrs = 1; /* Make sure we get the correct case */
531 
532 	DBG("nvram: Checking bank 0...\n");
533 
534 	gen_bank0 = core99_check((u8 *)nvram_data);
535 	gen_bank1 = core99_check((u8 *)nvram_data + NVRAM_SIZE);
536 	core99_bank = (gen_bank0 < gen_bank1) ? 1 : 0;
537 
538 	DBG("nvram: gen0=%d, gen1=%d\n", gen_bank0, gen_bank1);
539 	DBG("nvram: Active bank is: %d\n", core99_bank);
540 
541 	for (i=0; i<NVRAM_SIZE; i++)
542 		nvram_image[i] = nvram_data[i + core99_bank*NVRAM_SIZE];
543 
544 	ppc_md.nvram_read_val	= core99_nvram_read_byte;
545 	ppc_md.nvram_write_val	= core99_nvram_write_byte;
546 	ppc_md.nvram_read	= core99_nvram_read;
547 	ppc_md.nvram_write	= core99_nvram_write;
548 	ppc_md.nvram_size	= core99_nvram_size;
549 	ppc_md.nvram_sync	= core99_nvram_sync;
550 	ppc_md.machine_shutdown	= core99_nvram_sync;
551 	/*
552 	 * Maybe we could be smarter here though making an exclusive list
553 	 * of known flash chips is a bit nasty as older OF didn't provide us
554 	 * with a useful "compatible" entry. A solution would be to really
555 	 * identify the chip using flash id commands and base ourselves on
556 	 * a list of known chips IDs
557 	 */
558 	if (device_is_compatible(dp, "amd-0137")) {
559 		core99_erase_bank = amd_erase_bank;
560 		core99_write_bank = amd_write_bank;
561 	} else {
562 		core99_erase_bank = sm_erase_bank;
563 		core99_write_bank = sm_write_bank;
564 	}
565 	return 0;
566 }
567 
568 int __init pmac_nvram_init(void)
569 {
570 	struct device_node *dp;
571 	struct resource r1, r2;
572 	unsigned int s1 = 0, s2 = 0;
573 	int err = 0;
574 
575 	nvram_naddrs = 0;
576 
577 	dp = of_find_node_by_name(NULL, "nvram");
578 	if (dp == NULL) {
579 		printk(KERN_ERR "Can't find NVRAM device\n");
580 		return -ENODEV;
581 	}
582 
583 	/* Try to obtain an address */
584 	if (of_address_to_resource(dp, 0, &r1) == 0) {
585 		nvram_naddrs = 1;
586 		s1 = (r1.end - r1.start) + 1;
587 		if (of_address_to_resource(dp, 1, &r2) == 0) {
588 			nvram_naddrs = 2;
589 			s2 = (r2.end - r2.start) + 1;
590 		}
591 	}
592 
593 	is_core_99 = device_is_compatible(dp, "nvram,flash");
594 	if (is_core_99) {
595 		err = core99_nvram_setup(dp, r1.start);
596 		goto bail;
597 	}
598 
599 #ifdef CONFIG_PPC32
600 	if (machine_is(chrp) && nvram_naddrs == 1) {
601 		nvram_data = ioremap(r1.start, s1);
602 		nvram_mult = 1;
603 		ppc_md.nvram_read_val	= direct_nvram_read_byte;
604 		ppc_md.nvram_write_val	= direct_nvram_write_byte;
605 	} else if (nvram_naddrs == 1) {
606 		nvram_data = ioremap(r1.start, s1);
607 		nvram_mult = (s1 + NVRAM_SIZE - 1) / NVRAM_SIZE;
608 		ppc_md.nvram_read_val	= direct_nvram_read_byte;
609 		ppc_md.nvram_write_val	= direct_nvram_write_byte;
610 	} else if (nvram_naddrs == 2) {
611 		nvram_addr = ioremap(r1.start, s1);
612 		nvram_data = ioremap(r2.start, s2);
613 		ppc_md.nvram_read_val	= indirect_nvram_read_byte;
614 		ppc_md.nvram_write_val	= indirect_nvram_write_byte;
615 	} else if (nvram_naddrs == 0 && sys_ctrler == SYS_CTRLER_PMU) {
616 #ifdef CONFIG_ADB_PMU
617 		nvram_naddrs = -1;
618 		ppc_md.nvram_read_val	= pmu_nvram_read_byte;
619 		ppc_md.nvram_write_val	= pmu_nvram_write_byte;
620 #endif /* CONFIG_ADB_PMU */
621 	} else {
622 		printk(KERN_ERR "Incompatible type of NVRAM\n");
623 		err = -ENXIO;
624 	}
625 #endif /* CONFIG_PPC32 */
626 bail:
627 	of_node_put(dp);
628 	if (err == 0)
629 		lookup_partitions();
630 	return err;
631 }
632 
633 int pmac_get_partition(int partition)
634 {
635 	return nvram_partitions[partition];
636 }
637 
638 u8 pmac_xpram_read(int xpaddr)
639 {
640 	int offset = pmac_get_partition(pmac_nvram_XPRAM);
641 
642 	if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
643 		return 0xff;
644 
645 	return ppc_md.nvram_read_val(xpaddr + offset);
646 }
647 
648 void pmac_xpram_write(int xpaddr, u8 data)
649 {
650 	int offset = pmac_get_partition(pmac_nvram_XPRAM);
651 
652 	if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
653 		return;
654 
655 	ppc_md.nvram_write_val(xpaddr + offset, data);
656 }
657 
658 EXPORT_SYMBOL(pmac_get_partition);
659 EXPORT_SYMBOL(pmac_xpram_read);
660 EXPORT_SYMBOL(pmac_xpram_write);
661