1 /*
2  *  Early boot support code for BootX bootloader
3  *
4  *  Copyright (C) 2005 Ben. Herrenschmidt (benh@kernel.crashing.org)
5  *
6  *  This program is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU General Public License
8  *  as published by the Free Software Foundation; either version
9  *  2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/string.h>
14 #include <linux/init.h>
15 #include <generated/utsrelease.h>
16 #include <asm/sections.h>
17 #include <asm/prom.h>
18 #include <asm/page.h>
19 #include <asm/bootx.h>
20 #include <asm/btext.h>
21 #include <asm/io.h>
22 #include <asm/setup.h>
23 
24 #undef DEBUG
25 #define SET_BOOT_BAT
26 
27 #ifdef DEBUG
28 #define DBG(fmt...) do { bootx_printf(fmt); } while(0)
29 #else
30 #define DBG(fmt...) do { } while(0)
31 #endif
32 
33 extern void __start(unsigned long r3, unsigned long r4, unsigned long r5);
34 
35 static unsigned long __initdata bootx_dt_strbase;
36 static unsigned long __initdata bootx_dt_strend;
37 static unsigned long __initdata bootx_node_chosen;
38 static boot_infos_t * __initdata bootx_info;
39 static char __initdata bootx_disp_path[256];
40 
41 /* Is boot-info compatible ? */
42 #define BOOT_INFO_IS_COMPATIBLE(bi) \
43 	((bi)->compatible_version <= BOOT_INFO_VERSION)
44 #define BOOT_INFO_IS_V2_COMPATIBLE(bi)	((bi)->version >= 2)
45 #define BOOT_INFO_IS_V4_COMPATIBLE(bi)	((bi)->version >= 4)
46 
47 #ifdef CONFIG_BOOTX_TEXT
48 static void __init bootx_printf(const char *format, ...)
49 {
50 	const char *p, *q, *s;
51 	va_list args;
52 	unsigned long v;
53 
54 	va_start(args, format);
55 	for (p = format; *p != 0; p = q) {
56 		for (q = p; *q != 0 && *q != '\n' && *q != '%'; ++q)
57 			;
58 		if (q > p)
59 			btext_drawtext(p, q - p);
60 		if (*q == 0)
61 			break;
62 		if (*q == '\n') {
63 			++q;
64 			btext_flushline();
65 			btext_drawstring("\r\n");
66 			btext_flushline();
67 			continue;
68 		}
69 		++q;
70 		if (*q == 0)
71 			break;
72 		switch (*q) {
73 		case 's':
74 			++q;
75 			s = va_arg(args, const char *);
76 			if (s == NULL)
77 				s = "<NULL>";
78 			btext_drawstring(s);
79 			break;
80 		case 'x':
81 			++q;
82 			v = va_arg(args, unsigned long);
83 			btext_drawhex(v);
84 			break;
85 		}
86 	}
87 }
88 #else /* CONFIG_BOOTX_TEXT */
89 static void __init bootx_printf(const char *format, ...) {}
90 #endif /* CONFIG_BOOTX_TEXT */
91 
92 static void * __init bootx_early_getprop(unsigned long base,
93 					 unsigned long node,
94 					 char *prop)
95 {
96 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
97 	u32 *ppp = &np->properties;
98 
99 	while(*ppp) {
100 		struct bootx_dt_prop *pp =
101 			(struct bootx_dt_prop *)(base + *ppp);
102 
103 		if (strcmp((char *)((unsigned long)pp->name + base),
104 			   prop) == 0) {
105 			return (void *)((unsigned long)pp->value + base);
106 		}
107 		ppp = &pp->next;
108 	}
109 	return NULL;
110 }
111 
112 #define dt_push_token(token, mem) \
113 	do { \
114 		*(mem) = _ALIGN_UP(*(mem),4); \
115 		*((u32 *)*(mem)) = token; \
116 		*(mem) += 4; \
117 	} while(0)
118 
119 static unsigned long __init bootx_dt_find_string(char *str)
120 {
121 	char *s, *os;
122 
123 	s = os = (char *)bootx_dt_strbase;
124 	s += 4;
125 	while (s <  (char *)bootx_dt_strend) {
126 		if (strcmp(s, str) == 0)
127 			return s - os;
128 		s += strlen(s) + 1;
129 	}
130 	return 0;
131 }
132 
133 static void __init bootx_dt_add_prop(char *name, void *data, int size,
134 				  unsigned long *mem_end)
135 {
136 	unsigned long soff = bootx_dt_find_string(name);
137 	if (data == NULL)
138 		size = 0;
139 	if (soff == 0) {
140 		bootx_printf("WARNING: Can't find string index for <%s>\n",
141 			     name);
142 		return;
143 	}
144 	if (size > 0x20000) {
145 		bootx_printf("WARNING: ignoring large property ");
146 		bootx_printf("%s length 0x%x\n", name, size);
147 		return;
148 	}
149 	dt_push_token(OF_DT_PROP, mem_end);
150 	dt_push_token(size, mem_end);
151 	dt_push_token(soff, mem_end);
152 
153 	/* push property content */
154 	if (size && data) {
155 		memcpy((void *)*mem_end, data, size);
156 		*mem_end = _ALIGN_UP(*mem_end + size, 4);
157 	}
158 }
159 
160 static void __init bootx_add_chosen_props(unsigned long base,
161 					  unsigned long *mem_end)
162 {
163 	u32 val;
164 
165 	bootx_dt_add_prop("linux,bootx", NULL, 0, mem_end);
166 
167 	if (bootx_info->kernelParamsOffset) {
168 		char *args = (char *)((unsigned long)bootx_info) +
169 			bootx_info->kernelParamsOffset;
170 		bootx_dt_add_prop("bootargs", args, strlen(args) + 1, mem_end);
171 	}
172 	if (bootx_info->ramDisk) {
173 		val = ((unsigned long)bootx_info) + bootx_info->ramDisk;
174 		bootx_dt_add_prop("linux,initrd-start", &val, 4, mem_end);
175 		val += bootx_info->ramDiskSize;
176 		bootx_dt_add_prop("linux,initrd-end", &val, 4, mem_end);
177 	}
178 	if (strlen(bootx_disp_path))
179 		bootx_dt_add_prop("linux,stdout-path", bootx_disp_path,
180 				  strlen(bootx_disp_path) + 1, mem_end);
181 }
182 
183 static void __init bootx_add_display_props(unsigned long base,
184 					   unsigned long *mem_end,
185 					   int has_real_node)
186 {
187 	boot_infos_t *bi = bootx_info;
188 	u32 tmp;
189 
190 	if (has_real_node) {
191 		bootx_dt_add_prop("linux,boot-display", NULL, 0, mem_end);
192 		bootx_dt_add_prop("linux,opened", NULL, 0, mem_end);
193 	} else
194 		bootx_dt_add_prop("linux,bootx-noscreen", NULL, 0, mem_end);
195 
196 	tmp = bi->dispDeviceDepth;
197 	bootx_dt_add_prop("linux,bootx-depth", &tmp, 4, mem_end);
198 	tmp = bi->dispDeviceRect[2] - bi->dispDeviceRect[0];
199 	bootx_dt_add_prop("linux,bootx-width", &tmp, 4, mem_end);
200 	tmp = bi->dispDeviceRect[3] - bi->dispDeviceRect[1];
201 	bootx_dt_add_prop("linux,bootx-height", &tmp, 4, mem_end);
202 	tmp = bi->dispDeviceRowBytes;
203 	bootx_dt_add_prop("linux,bootx-linebytes", &tmp, 4, mem_end);
204 	tmp = (u32)bi->dispDeviceBase;
205 	if (tmp == 0)
206 		tmp = (u32)bi->logicalDisplayBase;
207 	tmp += bi->dispDeviceRect[1] * bi->dispDeviceRowBytes;
208 	tmp += bi->dispDeviceRect[0] * ((bi->dispDeviceDepth + 7) / 8);
209 	bootx_dt_add_prop("linux,bootx-addr", &tmp, 4, mem_end);
210 }
211 
212 static void __init bootx_dt_add_string(char *s, unsigned long *mem_end)
213 {
214 	unsigned int l = strlen(s) + 1;
215 	memcpy((void *)*mem_end, s, l);
216 	bootx_dt_strend = *mem_end = *mem_end + l;
217 }
218 
219 static void __init bootx_scan_dt_build_strings(unsigned long base,
220 					       unsigned long node,
221 					       unsigned long *mem_end)
222 {
223 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
224 	u32 *cpp, *ppp = &np->properties;
225 	unsigned long soff;
226 	char *namep;
227 
228 	/* Keep refs to known nodes */
229 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
230        	if (namep == NULL) {
231 		bootx_printf("Node without a full name !\n");
232 		namep = "";
233 	}
234 	DBG("* strings: %s\n", namep);
235 
236 	if (!strcmp(namep, "/chosen")) {
237 		DBG(" detected /chosen ! adding properties names !\n");
238 		bootx_dt_add_string("linux,bootx", mem_end);
239 		bootx_dt_add_string("linux,stdout-path", mem_end);
240 		bootx_dt_add_string("linux,initrd-start", mem_end);
241 		bootx_dt_add_string("linux,initrd-end", mem_end);
242 		bootx_dt_add_string("bootargs", mem_end);
243 		bootx_node_chosen = node;
244 	}
245 	if (node == bootx_info->dispDeviceRegEntryOffset) {
246 		DBG(" detected display ! adding properties names !\n");
247 		bootx_dt_add_string("linux,boot-display", mem_end);
248 		bootx_dt_add_string("linux,opened", mem_end);
249 		strlcpy(bootx_disp_path, namep, sizeof(bootx_disp_path));
250 	}
251 
252 	/* get and store all property names */
253 	while (*ppp) {
254 		struct bootx_dt_prop *pp =
255 			(struct bootx_dt_prop *)(base + *ppp);
256 
257 		namep = pp->name ? (char *)(base + pp->name) : NULL;
258  		if (namep == NULL || strcmp(namep, "name") == 0)
259  			goto next;
260 		/* get/create string entry */
261 		soff = bootx_dt_find_string(namep);
262 		if (soff == 0)
263 			bootx_dt_add_string(namep, mem_end);
264 	next:
265 		ppp = &pp->next;
266 	}
267 
268 	/* do all our children */
269 	cpp = &np->child;
270 	while(*cpp) {
271 		np = (struct bootx_dt_node *)(base + *cpp);
272 		bootx_scan_dt_build_strings(base, *cpp, mem_end);
273 		cpp = &np->sibling;
274 	}
275 }
276 
277 static void __init bootx_scan_dt_build_struct(unsigned long base,
278 					      unsigned long node,
279 					      unsigned long *mem_end)
280 {
281 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
282 	u32 *cpp, *ppp = &np->properties;
283 	char *namep, *p, *ep, *lp;
284 	int l;
285 
286 	dt_push_token(OF_DT_BEGIN_NODE, mem_end);
287 
288 	/* get the node's full name */
289 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
290 	if (namep == NULL)
291 		namep = "";
292 	l = strlen(namep);
293 
294 	DBG("* struct: %s\n", namep);
295 
296 	/* Fixup an Apple bug where they have bogus \0 chars in the
297 	 * middle of the path in some properties, and extract
298 	 * the unit name (everything after the last '/').
299 	 */
300 	memcpy((void *)*mem_end, namep, l + 1);
301 	namep = (char *)*mem_end;
302 	for (lp = p = namep, ep = namep + l; p < ep; p++) {
303 		if (*p == '/')
304 			lp = namep;
305 		else if (*p != 0)
306 			*lp++ = *p;
307 	}
308 	*lp = 0;
309 	*mem_end = _ALIGN_UP((unsigned long)lp + 1, 4);
310 
311 	/* get and store all properties */
312 	while (*ppp) {
313 		struct bootx_dt_prop *pp =
314 			(struct bootx_dt_prop *)(base + *ppp);
315 
316 		namep = pp->name ? (char *)(base + pp->name) : NULL;
317 		/* Skip "name" */
318  		if (namep == NULL || !strcmp(namep, "name"))
319  			goto next;
320 		/* Skip "bootargs" in /chosen too as we replace it */
321 		if (node == bootx_node_chosen && !strcmp(namep, "bootargs"))
322 			goto next;
323 
324 		/* push property head */
325 		bootx_dt_add_prop(namep,
326 				  pp->value ? (void *)(base + pp->value): NULL,
327 				  pp->length, mem_end);
328 	next:
329 		ppp = &pp->next;
330 	}
331 
332 	if (node == bootx_node_chosen) {
333 		bootx_add_chosen_props(base, mem_end);
334 		if (bootx_info->dispDeviceRegEntryOffset == 0)
335 			bootx_add_display_props(base, mem_end, 0);
336 	}
337 	else if (node == bootx_info->dispDeviceRegEntryOffset)
338 		bootx_add_display_props(base, mem_end, 1);
339 
340 	/* do all our children */
341 	cpp = &np->child;
342 	while(*cpp) {
343 		np = (struct bootx_dt_node *)(base + *cpp);
344 		bootx_scan_dt_build_struct(base, *cpp, mem_end);
345 		cpp = &np->sibling;
346 	}
347 
348 	dt_push_token(OF_DT_END_NODE, mem_end);
349 }
350 
351 static unsigned long __init bootx_flatten_dt(unsigned long start)
352 {
353 	boot_infos_t *bi = bootx_info;
354 	unsigned long mem_start, mem_end;
355 	struct boot_param_header *hdr;
356 	unsigned long base;
357 	u64 *rsvmap;
358 
359 	/* Start using memory after the big blob passed by BootX, get
360 	 * some space for the header
361 	 */
362 	mem_start = mem_end = _ALIGN_UP(((unsigned long)bi) + start, 4);
363 	DBG("Boot params header at: %x\n", mem_start);
364 	hdr = (struct boot_param_header *)mem_start;
365 	mem_end += sizeof(struct boot_param_header);
366 	rsvmap = (u64 *)(_ALIGN_UP(mem_end, 8));
367 	hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - mem_start;
368 	mem_end = ((unsigned long)rsvmap) + 8 * sizeof(u64);
369 
370 	/* Get base of tree */
371 	base = ((unsigned long)bi) + bi->deviceTreeOffset;
372 
373 	/* Build string array */
374 	DBG("Building string array at: %x\n", mem_end);
375 	DBG("Device Tree Base=%x\n", base);
376 	bootx_dt_strbase = mem_end;
377 	mem_end += 4;
378 	bootx_dt_strend = mem_end;
379 	bootx_scan_dt_build_strings(base, 4, &mem_end);
380 	/* Add some strings */
381 	bootx_dt_add_string("linux,bootx-noscreen", &mem_end);
382 	bootx_dt_add_string("linux,bootx-depth", &mem_end);
383 	bootx_dt_add_string("linux,bootx-width", &mem_end);
384 	bootx_dt_add_string("linux,bootx-height", &mem_end);
385 	bootx_dt_add_string("linux,bootx-linebytes", &mem_end);
386 	bootx_dt_add_string("linux,bootx-addr", &mem_end);
387 	/* Wrap up strings */
388 	hdr->off_dt_strings = bootx_dt_strbase - mem_start;
389 	hdr->dt_strings_size = bootx_dt_strend - bootx_dt_strbase;
390 
391 	/* Build structure */
392 	mem_end = _ALIGN(mem_end, 16);
393 	DBG("Building device tree structure at: %x\n", mem_end);
394 	hdr->off_dt_struct = mem_end - mem_start;
395 	bootx_scan_dt_build_struct(base, 4, &mem_end);
396 	dt_push_token(OF_DT_END, &mem_end);
397 
398 	/* Finish header */
399 	hdr->boot_cpuid_phys = 0;
400 	hdr->magic = OF_DT_HEADER;
401 	hdr->totalsize = mem_end - mem_start;
402 	hdr->version = OF_DT_VERSION;
403 	/* Version 16 is not backward compatible */
404 	hdr->last_comp_version = 0x10;
405 
406 	/* Reserve the whole thing and copy the reserve map in, we
407 	 * also bump mem_reserve_cnt to cause further reservations to
408 	 * fail since it's too late.
409 	 */
410 	mem_end = _ALIGN(mem_end, PAGE_SIZE);
411 	DBG("End of boot params: %x\n", mem_end);
412 	rsvmap[0] = mem_start;
413 	rsvmap[1] = mem_end;
414 	if (bootx_info->ramDisk) {
415 		rsvmap[2] = ((unsigned long)bootx_info) + bootx_info->ramDisk;
416 		rsvmap[3] = rsvmap[2] + bootx_info->ramDiskSize;
417 		rsvmap[4] = 0;
418 		rsvmap[5] = 0;
419 	} else {
420 		rsvmap[2] = 0;
421 		rsvmap[3] = 0;
422 	}
423 
424 	return (unsigned long)hdr;
425 }
426 
427 
428 #ifdef CONFIG_BOOTX_TEXT
429 static void __init btext_welcome(boot_infos_t *bi)
430 {
431 	unsigned long flags;
432 	unsigned long pvr;
433 
434 	bootx_printf("Welcome to Linux, kernel " UTS_RELEASE "\n");
435 	bootx_printf("\nlinked at        : 0x%x", KERNELBASE);
436 	bootx_printf("\nframe buffer at  : 0x%x", bi->dispDeviceBase);
437 	bootx_printf(" (phys), 0x%x", bi->logicalDisplayBase);
438 	bootx_printf(" (log)");
439 	bootx_printf("\nklimit           : 0x%x",(unsigned long)klimit);
440 	bootx_printf("\nboot_info at     : 0x%x", bi);
441 	__asm__ __volatile__ ("mfmsr %0" : "=r" (flags));
442 	bootx_printf("\nMSR              : 0x%x", flags);
443 	__asm__ __volatile__ ("mfspr %0, 287" : "=r" (pvr));
444 	bootx_printf("\nPVR              : 0x%x", pvr);
445 	pvr >>= 16;
446 	if (pvr > 1) {
447 	    __asm__ __volatile__ ("mfspr %0, 1008" : "=r" (flags));
448 	    bootx_printf("\nHID0             : 0x%x", flags);
449 	}
450 	if (pvr == 8 || pvr == 12 || pvr == 0x800c) {
451 	    __asm__ __volatile__ ("mfspr %0, 1019" : "=r" (flags));
452 	    bootx_printf("\nICTC             : 0x%x", flags);
453 	}
454 #ifdef DEBUG
455 	bootx_printf("\n\n");
456 	bootx_printf("bi->deviceTreeOffset   : 0x%x\n",
457 		     bi->deviceTreeOffset);
458 	bootx_printf("bi->deviceTreeSize     : 0x%x\n",
459 		     bi->deviceTreeSize);
460 #endif
461 	bootx_printf("\n\n");
462 }
463 #endif /* CONFIG_BOOTX_TEXT */
464 
465 void __init bootx_init(unsigned long r3, unsigned long r4)
466 {
467 	boot_infos_t *bi = (boot_infos_t *) r4;
468 	unsigned long hdr;
469 	unsigned long space;
470 	unsigned long ptr, x;
471 	char *model;
472 	unsigned long offset = reloc_offset();
473 
474 	reloc_got2(offset);
475 
476 	bootx_info = bi;
477 
478 	/* We haven't cleared any bss at this point, make sure
479 	 * what we need is initialized
480 	 */
481 	bootx_dt_strbase = bootx_dt_strend = 0;
482 	bootx_node_chosen = 0;
483 	bootx_disp_path[0] = 0;
484 
485 	if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
486 		bi->logicalDisplayBase = bi->dispDeviceBase;
487 
488 	/* Fixup depth 16 -> 15 as that's what MacOS calls 16bpp */
489 	if (bi->dispDeviceDepth == 16)
490 		bi->dispDeviceDepth = 15;
491 
492 
493 #ifdef CONFIG_BOOTX_TEXT
494 	ptr = (unsigned long)bi->logicalDisplayBase;
495 	ptr += bi->dispDeviceRect[1] * bi->dispDeviceRowBytes;
496 	ptr += bi->dispDeviceRect[0] * ((bi->dispDeviceDepth + 7) / 8);
497 	btext_setup_display(bi->dispDeviceRect[2] - bi->dispDeviceRect[0],
498 			    bi->dispDeviceRect[3] - bi->dispDeviceRect[1],
499 			    bi->dispDeviceDepth, bi->dispDeviceRowBytes,
500 			    (unsigned long)bi->logicalDisplayBase);
501 	btext_clearscreen();
502 	btext_flushscreen();
503 #endif /* CONFIG_BOOTX_TEXT */
504 
505 	/*
506 	 * Test if boot-info is compatible.  Done only in config
507 	 * CONFIG_BOOTX_TEXT since there is nothing much we can do
508 	 * with an incompatible version, except display a message
509 	 * and eventually hang the processor...
510 	 *
511 	 * I'll try to keep enough of boot-info compatible in the
512 	 * future to always allow display of this message;
513 	 */
514 	if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
515 		bootx_printf(" !!! WARNING - Incompatible version"
516 			     " of BootX !!!\n\n\n");
517 		for (;;)
518 			;
519 	}
520 	if (bi->architecture != BOOT_ARCH_PCI) {
521 		bootx_printf(" !!! WARNING - Usupported machine"
522 			     " architecture !\n");
523 		for (;;)
524 			;
525 	}
526 
527 #ifdef CONFIG_BOOTX_TEXT
528 	btext_welcome(bi);
529 #endif
530 
531 	/* New BootX enters kernel with MMU off, i/os are not allowed
532 	 * here. This hack will have been done by the boostrap anyway.
533 	 */
534 	if (bi->version < 4) {
535 		/*
536 		 * XXX If this is an iMac, turn off the USB controller.
537 		 */
538 		model = (char *) bootx_early_getprop(r4 + bi->deviceTreeOffset,
539 						     4, "model");
540 		if (model
541 		    && (strcmp(model, "iMac,1") == 0
542 			|| strcmp(model, "PowerMac1,1") == 0)) {
543 			bootx_printf("iMac,1 detected, shutting down USB\n");
544 			out_le32((unsigned __iomem *)0x80880008, 1);	/* XXX */
545 		}
546 	}
547 
548 	/* Get a pointer that points above the device tree, args, ramdisk,
549 	 * etc... to use for generating the flattened tree
550 	 */
551 	if (bi->version < 5) {
552 		space = bi->deviceTreeOffset + bi->deviceTreeSize;
553 		if (bi->ramDisk >= space)
554 			space = bi->ramDisk + bi->ramDiskSize;
555 	} else
556 		space = bi->totalParamsSize;
557 
558 	bootx_printf("Total space used by parameters & ramdisk: 0x%x\n", space);
559 
560 	/* New BootX will have flushed all TLBs and enters kernel with
561 	 * MMU switched OFF, so this should not be useful anymore.
562 	 */
563 	if (bi->version < 4) {
564 		bootx_printf("Touching pages...\n");
565 
566 		/*
567 		 * Touch each page to make sure the PTEs for them
568 		 * are in the hash table - the aim is to try to avoid
569 		 * getting DSI exceptions while copying the kernel image.
570 		 */
571 		for (ptr = ((unsigned long) &_stext) & PAGE_MASK;
572 		     ptr < (unsigned long)bi + space; ptr += PAGE_SIZE)
573 			x = *(volatile unsigned long *)ptr;
574 	}
575 
576 	/* Ok, now we need to generate a flattened device-tree to pass
577 	 * to the kernel
578 	 */
579 	bootx_printf("Preparing boot params...\n");
580 
581 	hdr = bootx_flatten_dt(space);
582 
583 #ifdef CONFIG_BOOTX_TEXT
584 #ifdef SET_BOOT_BAT
585 	bootx_printf("Preparing BAT...\n");
586 	btext_prepare_BAT();
587 #else
588 	btext_unmap();
589 #endif
590 #endif
591 
592 	reloc_got2(-offset);
593 
594 	__start(hdr, KERNELBASE + offset, 0);
595 }
596