xref: /openbmc/linux/arch/powerpc/platforms/powermac/nvram.c (revision 023e41632e065d49bcbe31b3c4b336217f96a271)
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/export.h>
12 #include <linux/kernel.h>
13 #include <linux/stddef.h>
14 #include <linux/string.h>
15 #include <linux/nvram.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/errno.h>
19 #include <linux/adb.h>
20 #include <linux/pmu.h>
21 #include <linux/memblock.h>
22 #include <linux/completion.h>
23 #include <linux/spinlock.h>
24 #include <asm/sections.h>
25 #include <asm/io.h>
26 #include <asm/prom.h>
27 #include <asm/machdep.h>
28 #include <asm/nvram.h>
29 
30 #include "pmac.h"
31 
32 #define DEBUG
33 
34 #ifdef DEBUG
35 #define DBG(x...) printk(x)
36 #else
37 #define DBG(x...)
38 #endif
39 
40 #define NVRAM_SIZE		0x2000	/* 8kB of non-volatile RAM */
41 
42 #define CORE99_SIGNATURE	0x5a
43 #define CORE99_ADLER_START	0x14
44 
45 /* On Core99, nvram is either a sharp, a micron or an AMD flash */
46 #define SM_FLASH_STATUS_DONE	0x80
47 #define SM_FLASH_STATUS_ERR	0x38
48 
49 #define SM_FLASH_CMD_ERASE_CONFIRM	0xd0
50 #define SM_FLASH_CMD_ERASE_SETUP	0x20
51 #define SM_FLASH_CMD_RESET		0xff
52 #define SM_FLASH_CMD_WRITE_SETUP	0x40
53 #define SM_FLASH_CMD_CLEAR_STATUS	0x50
54 #define SM_FLASH_CMD_READ_STATUS	0x70
55 
56 /* CHRP NVRAM header */
57 struct chrp_header {
58   u8		signature;
59   u8		cksum;
60   u16		len;
61   char          name[12];
62   u8		data[0];
63 };
64 
65 struct core99_header {
66   struct chrp_header	hdr;
67   u32			adler;
68   u32			generation;
69   u32			reserved[2];
70 };
71 
72 /*
73  * Read and write the non-volatile RAM on PowerMacs and CHRP machines.
74  */
75 static int nvram_naddrs;
76 static volatile unsigned char __iomem *nvram_data;
77 static int is_core_99;
78 static int core99_bank = 0;
79 static int nvram_partitions[3];
80 // XXX Turn that into a sem
81 static DEFINE_RAW_SPINLOCK(nv_lock);
82 
83 static int (*core99_write_bank)(int bank, u8* datas);
84 static int (*core99_erase_bank)(int bank);
85 
86 static char *nvram_image;
87 
88 
89 static unsigned char core99_nvram_read_byte(int addr)
90 {
91 	if (nvram_image == NULL)
92 		return 0xff;
93 	return nvram_image[addr];
94 }
95 
96 static void core99_nvram_write_byte(int addr, unsigned char val)
97 {
98 	if (nvram_image == NULL)
99 		return;
100 	nvram_image[addr] = val;
101 }
102 
103 static ssize_t core99_nvram_read(char *buf, size_t count, loff_t *index)
104 {
105 	int i;
106 
107 	if (nvram_image == NULL)
108 		return -ENODEV;
109 	if (*index > NVRAM_SIZE)
110 		return 0;
111 
112 	i = *index;
113 	if (i + count > NVRAM_SIZE)
114 		count = NVRAM_SIZE - i;
115 
116 	memcpy(buf, &nvram_image[i], count);
117 	*index = i + count;
118 	return count;
119 }
120 
121 static ssize_t core99_nvram_write(char *buf, size_t count, loff_t *index)
122 {
123 	int i;
124 
125 	if (nvram_image == NULL)
126 		return -ENODEV;
127 	if (*index > NVRAM_SIZE)
128 		return 0;
129 
130 	i = *index;
131 	if (i + count > NVRAM_SIZE)
132 		count = NVRAM_SIZE - i;
133 
134 	memcpy(&nvram_image[i], buf, count);
135 	*index = i + count;
136 	return count;
137 }
138 
139 static ssize_t core99_nvram_size(void)
140 {
141 	if (nvram_image == NULL)
142 		return -ENODEV;
143 	return NVRAM_SIZE;
144 }
145 
146 #ifdef CONFIG_PPC32
147 static volatile unsigned char __iomem *nvram_addr;
148 static int nvram_mult;
149 
150 static ssize_t ppc32_nvram_size(void)
151 {
152 	return NVRAM_SIZE;
153 }
154 
155 static unsigned char direct_nvram_read_byte(int addr)
156 {
157 	return in_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult]);
158 }
159 
160 static void direct_nvram_write_byte(int addr, unsigned char val)
161 {
162 	out_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult], val);
163 }
164 
165 
166 static unsigned char indirect_nvram_read_byte(int addr)
167 {
168 	unsigned char val;
169 	unsigned long flags;
170 
171 	raw_spin_lock_irqsave(&nv_lock, flags);
172 	out_8(nvram_addr, addr >> 5);
173 	val = in_8(&nvram_data[(addr & 0x1f) << 4]);
174 	raw_spin_unlock_irqrestore(&nv_lock, flags);
175 
176 	return val;
177 }
178 
179 static void indirect_nvram_write_byte(int addr, unsigned char val)
180 {
181 	unsigned long flags;
182 
183 	raw_spin_lock_irqsave(&nv_lock, flags);
184 	out_8(nvram_addr, addr >> 5);
185 	out_8(&nvram_data[(addr & 0x1f) << 4], val);
186 	raw_spin_unlock_irqrestore(&nv_lock, flags);
187 }
188 
189 
190 #ifdef CONFIG_ADB_PMU
191 
192 static void pmu_nvram_complete(struct adb_request *req)
193 {
194 	if (req->arg)
195 		complete((struct completion *)req->arg);
196 }
197 
198 static unsigned char pmu_nvram_read_byte(int addr)
199 {
200 	struct adb_request req;
201 	DECLARE_COMPLETION_ONSTACK(req_complete);
202 
203 	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
204 	if (pmu_request(&req, pmu_nvram_complete, 3, PMU_READ_NVRAM,
205 			(addr >> 8) & 0xff, addr & 0xff))
206 		return 0xff;
207 	if (system_state == SYSTEM_RUNNING)
208 		wait_for_completion(&req_complete);
209 	while (!req.complete)
210 		pmu_poll();
211 	return req.reply[0];
212 }
213 
214 static void pmu_nvram_write_byte(int addr, unsigned char val)
215 {
216 	struct adb_request req;
217 	DECLARE_COMPLETION_ONSTACK(req_complete);
218 
219 	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
220 	if (pmu_request(&req, pmu_nvram_complete, 4, PMU_WRITE_NVRAM,
221 			(addr >> 8) & 0xff, addr & 0xff, val))
222 		return;
223 	if (system_state == SYSTEM_RUNNING)
224 		wait_for_completion(&req_complete);
225 	while (!req.complete)
226 		pmu_poll();
227 }
228 
229 #endif /* CONFIG_ADB_PMU */
230 #endif /* CONFIG_PPC32 */
231 
232 static u8 chrp_checksum(struct chrp_header* hdr)
233 {
234 	u8 *ptr;
235 	u16 sum = hdr->signature;
236 	for (ptr = (u8 *)&hdr->len; ptr < hdr->data; ptr++)
237 		sum += *ptr;
238 	while (sum > 0xFF)
239 		sum = (sum & 0xFF) + (sum>>8);
240 	return sum;
241 }
242 
243 static u32 core99_calc_adler(u8 *buffer)
244 {
245 	int cnt;
246 	u32 low, high;
247 
248    	buffer += CORE99_ADLER_START;
249 	low = 1;
250 	high = 0;
251 	for (cnt=0; cnt<(NVRAM_SIZE-CORE99_ADLER_START); cnt++) {
252 		if ((cnt % 5000) == 0) {
253 			high  %= 65521UL;
254 			high %= 65521UL;
255 		}
256 		low += buffer[cnt];
257 		high += low;
258 	}
259 	low  %= 65521UL;
260 	high %= 65521UL;
261 
262 	return (high << 16) | low;
263 }
264 
265 static u32 core99_check(u8* datas)
266 {
267 	struct core99_header* hdr99 = (struct core99_header*)datas;
268 
269 	if (hdr99->hdr.signature != CORE99_SIGNATURE) {
270 		DBG("Invalid signature\n");
271 		return 0;
272 	}
273 	if (hdr99->hdr.cksum != chrp_checksum(&hdr99->hdr)) {
274 		DBG("Invalid checksum\n");
275 		return 0;
276 	}
277 	if (hdr99->adler != core99_calc_adler(datas)) {
278 		DBG("Invalid adler\n");
279 		return 0;
280 	}
281 	return hdr99->generation;
282 }
283 
284 static int sm_erase_bank(int bank)
285 {
286 	int stat;
287 	unsigned long timeout;
288 
289 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
290 
291        	DBG("nvram: Sharp/Micron Erasing bank %d...\n", bank);
292 
293 	out_8(base, SM_FLASH_CMD_ERASE_SETUP);
294 	out_8(base, SM_FLASH_CMD_ERASE_CONFIRM);
295 	timeout = 0;
296 	do {
297 		if (++timeout > 1000000) {
298 			printk(KERN_ERR "nvram: Sharp/Micron flash erase timeout !\n");
299 			break;
300 		}
301 		out_8(base, SM_FLASH_CMD_READ_STATUS);
302 		stat = in_8(base);
303 	} while (!(stat & SM_FLASH_STATUS_DONE));
304 
305 	out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
306 	out_8(base, SM_FLASH_CMD_RESET);
307 
308 	if (memchr_inv(base, 0xff, NVRAM_SIZE)) {
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 	if (memcmp(base, datas, NVRAM_SIZE)) {
343 		printk(KERN_ERR "nvram: Sharp/Micron flash write failed !\n");
344 		return -ENXIO;
345 	}
346 	return 0;
347 }
348 
349 static int amd_erase_bank(int bank)
350 {
351 	int stat = 0;
352 	unsigned long timeout;
353 
354 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
355 
356        	DBG("nvram: AMD Erasing bank %d...\n", bank);
357 
358 	/* Unlock 1 */
359 	out_8(base+0x555, 0xaa);
360 	udelay(1);
361 	/* Unlock 2 */
362 	out_8(base+0x2aa, 0x55);
363 	udelay(1);
364 
365 	/* Sector-Erase */
366 	out_8(base+0x555, 0x80);
367 	udelay(1);
368 	out_8(base+0x555, 0xaa);
369 	udelay(1);
370 	out_8(base+0x2aa, 0x55);
371 	udelay(1);
372 	out_8(base, 0x30);
373 	udelay(1);
374 
375 	timeout = 0;
376 	do {
377 		if (++timeout > 1000000) {
378 			printk(KERN_ERR "nvram: AMD flash erase timeout !\n");
379 			break;
380 		}
381 		stat = in_8(base) ^ in_8(base);
382 	} while (stat != 0);
383 
384 	/* Reset */
385 	out_8(base, 0xf0);
386 	udelay(1);
387 
388 	if (memchr_inv(base, 0xff, NVRAM_SIZE)) {
389 		printk(KERN_ERR "nvram: AMD flash erase failed !\n");
390 		return -ENXIO;
391 	}
392 	return 0;
393 }
394 
395 static int amd_write_bank(int bank, u8* datas)
396 {
397 	int i, stat = 0;
398 	unsigned long timeout;
399 
400 	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;
401 
402        	DBG("nvram: AMD Writing bank %d...\n", bank);
403 
404 	for (i=0; i<NVRAM_SIZE; i++) {
405 		/* Unlock 1 */
406 		out_8(base+0x555, 0xaa);
407 		udelay(1);
408 		/* Unlock 2 */
409 		out_8(base+0x2aa, 0x55);
410 		udelay(1);
411 
412 		/* Write single word */
413 		out_8(base+0x555, 0xa0);
414 		udelay(1);
415 		out_8(base+i, datas[i]);
416 
417 		timeout = 0;
418 		do {
419 			if (++timeout > 1000000) {
420 				printk(KERN_ERR "nvram: AMD flash write timeout !\n");
421 				break;
422 			}
423 			stat = in_8(base) ^ in_8(base);
424 		} while (stat != 0);
425 		if (stat != 0)
426 			break;
427 	}
428 
429 	/* Reset */
430 	out_8(base, 0xf0);
431 	udelay(1);
432 
433 	if (memcmp(base, datas, NVRAM_SIZE)) {
434 		printk(KERN_ERR "nvram: AMD flash write failed !\n");
435 		return -ENXIO;
436 	}
437 	return 0;
438 }
439 
440 static void __init lookup_partitions(void)
441 {
442 	u8 buffer[17];
443 	int i, offset;
444 	struct chrp_header* hdr;
445 
446 	if (pmac_newworld) {
447 		nvram_partitions[pmac_nvram_OF] = -1;
448 		nvram_partitions[pmac_nvram_XPRAM] = -1;
449 		nvram_partitions[pmac_nvram_NR] = -1;
450 		hdr = (struct chrp_header *)buffer;
451 
452 		offset = 0;
453 		buffer[16] = 0;
454 		do {
455 			for (i=0;i<16;i++)
456 				buffer[i] = ppc_md.nvram_read_val(offset+i);
457 			if (!strcmp(hdr->name, "common"))
458 				nvram_partitions[pmac_nvram_OF] = offset + 0x10;
459 			if (!strcmp(hdr->name, "APL,MacOS75")) {
460 				nvram_partitions[pmac_nvram_XPRAM] = offset + 0x10;
461 				nvram_partitions[pmac_nvram_NR] = offset + 0x110;
462 			}
463 			offset += (hdr->len * 0x10);
464 		} while(offset < NVRAM_SIZE);
465 	} else {
466 		nvram_partitions[pmac_nvram_OF] = 0x1800;
467 		nvram_partitions[pmac_nvram_XPRAM] = 0x1300;
468 		nvram_partitions[pmac_nvram_NR] = 0x1400;
469 	}
470 	DBG("nvram: OF partition at 0x%x\n", nvram_partitions[pmac_nvram_OF]);
471 	DBG("nvram: XP partition at 0x%x\n", nvram_partitions[pmac_nvram_XPRAM]);
472 	DBG("nvram: NR partition at 0x%x\n", nvram_partitions[pmac_nvram_NR]);
473 }
474 
475 static void core99_nvram_sync(void)
476 {
477 	struct core99_header* hdr99;
478 	unsigned long flags;
479 
480 	if (!is_core_99 || !nvram_data || !nvram_image)
481 		return;
482 
483 	raw_spin_lock_irqsave(&nv_lock, flags);
484 	if (!memcmp(nvram_image, (u8*)nvram_data + core99_bank*NVRAM_SIZE,
485 		NVRAM_SIZE))
486 		goto bail;
487 
488 	DBG("Updating nvram...\n");
489 
490 	hdr99 = (struct core99_header*)nvram_image;
491 	hdr99->generation++;
492 	hdr99->hdr.signature = CORE99_SIGNATURE;
493 	hdr99->hdr.cksum = chrp_checksum(&hdr99->hdr);
494 	hdr99->adler = core99_calc_adler(nvram_image);
495 	core99_bank = core99_bank ? 0 : 1;
496 	if (core99_erase_bank)
497 		if (core99_erase_bank(core99_bank)) {
498 			printk("nvram: Error erasing bank %d\n", core99_bank);
499 			goto bail;
500 		}
501 	if (core99_write_bank)
502 		if (core99_write_bank(core99_bank, nvram_image))
503 			printk("nvram: Error writing bank %d\n", core99_bank);
504  bail:
505 	raw_spin_unlock_irqrestore(&nv_lock, flags);
506 
507 #ifdef DEBUG
508        	mdelay(2000);
509 #endif
510 }
511 
512 static int __init core99_nvram_setup(struct device_node *dp, unsigned long addr)
513 {
514 	int i;
515 	u32 gen_bank0, gen_bank1;
516 
517 	if (nvram_naddrs < 1) {
518 		printk(KERN_ERR "nvram: no address\n");
519 		return -EINVAL;
520 	}
521 	nvram_image = memblock_alloc(NVRAM_SIZE, SMP_CACHE_BYTES);
522 	if (!nvram_image)
523 		panic("%s: Failed to allocate %u bytes\n", __func__,
524 		      NVRAM_SIZE);
525 	nvram_data = ioremap(addr, NVRAM_SIZE*2);
526 	nvram_naddrs = 1; /* Make sure we get the correct case */
527 
528 	DBG("nvram: Checking bank 0...\n");
529 
530 	gen_bank0 = core99_check((u8 *)nvram_data);
531 	gen_bank1 = core99_check((u8 *)nvram_data + NVRAM_SIZE);
532 	core99_bank = (gen_bank0 < gen_bank1) ? 1 : 0;
533 
534 	DBG("nvram: gen0=%d, gen1=%d\n", gen_bank0, gen_bank1);
535 	DBG("nvram: Active bank is: %d\n", core99_bank);
536 
537 	for (i=0; i<NVRAM_SIZE; i++)
538 		nvram_image[i] = nvram_data[i + core99_bank*NVRAM_SIZE];
539 
540 	ppc_md.nvram_read_val	= core99_nvram_read_byte;
541 	ppc_md.nvram_write_val	= core99_nvram_write_byte;
542 	ppc_md.nvram_read	= core99_nvram_read;
543 	ppc_md.nvram_write	= core99_nvram_write;
544 	ppc_md.nvram_size	= core99_nvram_size;
545 	ppc_md.nvram_sync	= core99_nvram_sync;
546 	ppc_md.machine_shutdown	= core99_nvram_sync;
547 	/*
548 	 * Maybe we could be smarter here though making an exclusive list
549 	 * of known flash chips is a bit nasty as older OF didn't provide us
550 	 * with a useful "compatible" entry. A solution would be to really
551 	 * identify the chip using flash id commands and base ourselves on
552 	 * a list of known chips IDs
553 	 */
554 	if (of_device_is_compatible(dp, "amd-0137")) {
555 		core99_erase_bank = amd_erase_bank;
556 		core99_write_bank = amd_write_bank;
557 	} else {
558 		core99_erase_bank = sm_erase_bank;
559 		core99_write_bank = sm_write_bank;
560 	}
561 	return 0;
562 }
563 
564 int __init pmac_nvram_init(void)
565 {
566 	struct device_node *dp;
567 	struct resource r1, r2;
568 	unsigned int s1 = 0, s2 = 0;
569 	int err = 0;
570 
571 	nvram_naddrs = 0;
572 
573 	dp = of_find_node_by_name(NULL, "nvram");
574 	if (dp == NULL) {
575 		printk(KERN_ERR "Can't find NVRAM device\n");
576 		return -ENODEV;
577 	}
578 
579 	/* Try to obtain an address */
580 	if (of_address_to_resource(dp, 0, &r1) == 0) {
581 		nvram_naddrs = 1;
582 		s1 = resource_size(&r1);
583 		if (of_address_to_resource(dp, 1, &r2) == 0) {
584 			nvram_naddrs = 2;
585 			s2 = resource_size(&r2);
586 		}
587 	}
588 
589 	is_core_99 = of_device_is_compatible(dp, "nvram,flash");
590 	if (is_core_99) {
591 		err = core99_nvram_setup(dp, r1.start);
592 		goto bail;
593 	}
594 
595 #ifdef CONFIG_PPC32
596 	if (machine_is(chrp) && nvram_naddrs == 1) {
597 		nvram_data = ioremap(r1.start, s1);
598 		nvram_mult = 1;
599 		ppc_md.nvram_read_val	= direct_nvram_read_byte;
600 		ppc_md.nvram_write_val	= direct_nvram_write_byte;
601 		ppc_md.nvram_size	= ppc32_nvram_size;
602 	} else if (nvram_naddrs == 1) {
603 		nvram_data = ioremap(r1.start, s1);
604 		nvram_mult = (s1 + NVRAM_SIZE - 1) / NVRAM_SIZE;
605 		ppc_md.nvram_read_val	= direct_nvram_read_byte;
606 		ppc_md.nvram_write_val	= direct_nvram_write_byte;
607 		ppc_md.nvram_size	= ppc32_nvram_size;
608 	} else if (nvram_naddrs == 2) {
609 		nvram_addr = ioremap(r1.start, s1);
610 		nvram_data = ioremap(r2.start, s2);
611 		ppc_md.nvram_read_val	= indirect_nvram_read_byte;
612 		ppc_md.nvram_write_val	= indirect_nvram_write_byte;
613 		ppc_md.nvram_size	= ppc32_nvram_size;
614 	} else if (nvram_naddrs == 0 && sys_ctrler == SYS_CTRLER_PMU) {
615 #ifdef CONFIG_ADB_PMU
616 		nvram_naddrs = -1;
617 		ppc_md.nvram_read_val	= pmu_nvram_read_byte;
618 		ppc_md.nvram_write_val	= pmu_nvram_write_byte;
619 		ppc_md.nvram_size	= ppc32_nvram_size;
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