xref: /linux/arch/powerpc/platforms/powermac/bootx_init.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
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/config.h>
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/init.h>
16 #include <linux/version.h>
17 #include <asm/sections.h>
18 #include <asm/prom.h>
19 #include <asm/page.h>
20 #include <asm/bootx.h>
21 #include <asm/bootinfo.h>
22 #include <asm/btext.h>
23 #include <asm/io.h>
24 
25 #undef DEBUG
26 #define SET_BOOT_BAT
27 
28 #ifdef DEBUG
29 #define DBG(fmt...) do { bootx_printf(fmt); } while(0)
30 #else
31 #define DBG(fmt...) do { } while(0)
32 #endif
33 
34 extern void __start(unsigned long r3, unsigned long r4, unsigned long r5);
35 
36 static unsigned long __initdata bootx_dt_strbase;
37 static unsigned long __initdata bootx_dt_strend;
38 static unsigned long __initdata bootx_node_chosen;
39 static boot_infos_t * __initdata bootx_info;
40 static char __initdata bootx_disp_path[256];
41 
42 /* Is boot-info compatible ? */
43 #define BOOT_INFO_IS_COMPATIBLE(bi) \
44 	((bi)->compatible_version <= BOOT_INFO_VERSION)
45 #define BOOT_INFO_IS_V2_COMPATIBLE(bi)	((bi)->version >= 2)
46 #define BOOT_INFO_IS_V4_COMPATIBLE(bi)	((bi)->version >= 4)
47 
48 #ifdef CONFIG_BOOTX_TEXT
49 static void __init bootx_printf(const char *format, ...)
50 {
51 	const char *p, *q, *s;
52 	va_list args;
53 	unsigned long v;
54 
55 	va_start(args, format);
56 	for (p = format; *p != 0; p = q) {
57 		for (q = p; *q != 0 && *q != '\n' && *q != '%'; ++q)
58 			;
59 		if (q > p)
60 			btext_drawtext(p, q - p);
61 		if (*q == 0)
62 			break;
63 		if (*q == '\n') {
64 			++q;
65 			btext_flushline();
66 			btext_drawstring("\r\n");
67 			btext_flushline();
68 			continue;
69 		}
70 		++q;
71 		if (*q == 0)
72 			break;
73 		switch (*q) {
74 		case 's':
75 			++q;
76 			s = va_arg(args, const char *);
77 			if (s == NULL)
78 				s = "<NULL>";
79 			btext_drawstring(s);
80 			break;
81 		case 'x':
82 			++q;
83 			v = va_arg(args, unsigned long);
84 			btext_drawhex(v);
85 			break;
86 		}
87 	}
88 }
89 #else /* CONFIG_BOOTX_TEXT */
90 static void __init bootx_printf(const char *format, ...) {}
91 #endif /* CONFIG_BOOTX_TEXT */
92 
93 static void * __init bootx_early_getprop(unsigned long base,
94 					 unsigned long node,
95 					 char *prop)
96 {
97 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
98 	u32 *ppp = &np->properties;
99 
100 	while(*ppp) {
101 		struct bootx_dt_prop *pp =
102 			(struct bootx_dt_prop *)(base + *ppp);
103 
104 		if (strcmp((char *)((unsigned long)pp->name + base),
105 			   prop) == 0) {
106 			return (void *)((unsigned long)pp->value + base);
107 		}
108 		ppp = &pp->next;
109 	}
110 	return NULL;
111 }
112 
113 #define dt_push_token(token, mem) \
114 	do { \
115 		*(mem) = _ALIGN_UP(*(mem),4); \
116 		*((u32 *)*(mem)) = token; \
117 		*(mem) += 4; \
118 	} while(0)
119 
120 static unsigned long __init bootx_dt_find_string(char *str)
121 {
122 	char *s, *os;
123 
124 	s = os = (char *)bootx_dt_strbase;
125 	s += 4;
126 	while (s <  (char *)bootx_dt_strend) {
127 		if (strcmp(s, str) == 0)
128 			return s - os;
129 		s += strlen(s) + 1;
130 	}
131 	return 0;
132 }
133 
134 static void __init bootx_dt_add_prop(char *name, void *data, int size,
135 				  unsigned long *mem_end)
136 {
137 	unsigned long soff = bootx_dt_find_string(name);
138 	if (data == NULL)
139 		size = 0;
140 	if (soff == 0) {
141 		bootx_printf("WARNING: Can't find string index for <%s>\n",
142 			     name);
143 		return;
144 	}
145 	if (size > 0x20000) {
146 		bootx_printf("WARNING: ignoring large property ");
147 		bootx_printf("%s length 0x%x\n", name, size);
148 		return;
149 	}
150 	dt_push_token(OF_DT_PROP, mem_end);
151 	dt_push_token(size, mem_end);
152 	dt_push_token(soff, mem_end);
153 
154 	/* push property content */
155 	if (size && data) {
156 		memcpy((void *)*mem_end, data, size);
157 		*mem_end = _ALIGN_UP(*mem_end + size, 4);
158 	}
159 }
160 
161 static void __init bootx_add_chosen_props(unsigned long base,
162 					  unsigned long *mem_end)
163 {
164 	u32 val;
165 
166 	if (bootx_info->kernelParamsOffset) {
167 		char *args = (char *)((unsigned long)bootx_info) +
168 			bootx_info->kernelParamsOffset;
169 		bootx_dt_add_prop("bootargs", args, strlen(args) + 1, mem_end);
170 	}
171 	if (bootx_info->ramDisk) {
172 		val = ((unsigned long)bootx_info) + bootx_info->ramDisk;
173 		bootx_dt_add_prop("linux,initrd-start", &val, 4, mem_end);
174 		val += bootx_info->ramDiskSize;
175 		bootx_dt_add_prop("linux,initrd-end", &val, 4, mem_end);
176 	}
177 	if (strlen(bootx_disp_path))
178 		bootx_dt_add_prop("linux,stdout-path", bootx_disp_path,
179 				  strlen(bootx_disp_path) + 1, mem_end);
180 }
181 
182 static void __init bootx_add_display_props(unsigned long base,
183 					   unsigned long *mem_end)
184 {
185 	bootx_dt_add_prop("linux,boot-display", NULL, 0, mem_end);
186 	bootx_dt_add_prop("linux,opened", NULL, 0, mem_end);
187 }
188 
189 static void __init bootx_dt_add_string(char *s, unsigned long *mem_end)
190 {
191 	unsigned int l = strlen(s) + 1;
192 	memcpy((void *)*mem_end, s, l);
193 	bootx_dt_strend = *mem_end = *mem_end + l;
194 }
195 
196 static void __init bootx_scan_dt_build_strings(unsigned long base,
197 					       unsigned long node,
198 					       unsigned long *mem_end)
199 {
200 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
201 	u32 *cpp, *ppp = &np->properties;
202 	unsigned long soff;
203 	char *namep;
204 
205 	/* Keep refs to known nodes */
206 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
207        	if (namep == NULL) {
208 		bootx_printf("Node without a full name !\n");
209 		namep = "";
210 	}
211 	DBG("* strings: %s\n", namep);
212 
213 	if (!strcmp(namep, "/chosen")) {
214 		DBG(" detected /chosen ! adding properties names !\n");
215 		bootx_dt_add_string("linux,platform", mem_end);
216 		bootx_dt_add_string("linux,stdout-path", mem_end);
217 		bootx_dt_add_string("linux,initrd-start", mem_end);
218 		bootx_dt_add_string("linux,initrd-end", mem_end);
219 		bootx_dt_add_string("bootargs", mem_end);
220 		bootx_node_chosen = node;
221 	}
222 	if (node == bootx_info->dispDeviceRegEntryOffset) {
223 		DBG(" detected display ! adding properties names !\n");
224 		bootx_dt_add_string("linux,boot-display", mem_end);
225 		bootx_dt_add_string("linux,opened", mem_end);
226 		strncpy(bootx_disp_path, namep, 255);
227 	}
228 
229 	/* get and store all property names */
230 	while (*ppp) {
231 		struct bootx_dt_prop *pp =
232 			(struct bootx_dt_prop *)(base + *ppp);
233 
234 		namep = pp->name ? (char *)(base + pp->name) : NULL;
235  		if (namep == NULL || strcmp(namep, "name") == 0)
236  			goto next;
237 		/* get/create string entry */
238 		soff = bootx_dt_find_string(namep);
239 		if (soff == 0)
240 			bootx_dt_add_string(namep, mem_end);
241 	next:
242 		ppp = &pp->next;
243 	}
244 
245 	/* do all our children */
246 	cpp = &np->child;
247 	while(*cpp) {
248 		np = (struct bootx_dt_node *)(base + *cpp);
249 		bootx_scan_dt_build_strings(base, *cpp, mem_end);
250 		cpp = &np->sibling;
251 	}
252 }
253 
254 static void __init bootx_scan_dt_build_struct(unsigned long base,
255 					      unsigned long node,
256 					      unsigned long *mem_end)
257 {
258 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
259 	u32 *cpp, *ppp = &np->properties;
260 	char *namep, *p, *ep, *lp;
261 	int l;
262 
263 	dt_push_token(OF_DT_BEGIN_NODE, mem_end);
264 
265 	/* get the node's full name */
266 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
267 	if (namep == NULL)
268 		namep = "";
269 	l = strlen(namep);
270 
271 	DBG("* struct: %s\n", namep);
272 
273 	/* Fixup an Apple bug where they have bogus \0 chars in the
274 	 * middle of the path in some properties, and extract
275 	 * the unit name (everything after the last '/').
276 	 */
277 	memcpy((void *)*mem_end, namep, l + 1);
278 	namep = (char *)*mem_end;
279 	for (lp = p = namep, ep = namep + l; p < ep; p++) {
280 		if (*p == '/')
281 			lp = namep;
282 		else if (*p != 0)
283 			*lp++ = *p;
284 	}
285 	*lp = 0;
286 	*mem_end = _ALIGN_UP((unsigned long)lp + 1, 4);
287 
288 	/* get and store all properties */
289 	while (*ppp) {
290 		struct bootx_dt_prop *pp =
291 			(struct bootx_dt_prop *)(base + *ppp);
292 
293 		namep = pp->name ? (char *)(base + pp->name) : NULL;
294 		/* Skip "name" */
295  		if (namep == NULL || !strcmp(namep, "name"))
296  			goto next;
297 		/* Skip "bootargs" in /chosen too as we replace it */
298 		if (node == bootx_node_chosen && !strcmp(namep, "bootargs"))
299 			goto next;
300 
301 		/* push property head */
302 		bootx_dt_add_prop(namep,
303 				  pp->value ? (void *)(base + pp->value): NULL,
304 				  pp->length, mem_end);
305 	next:
306 		ppp = &pp->next;
307 	}
308 
309 	if (node == bootx_node_chosen)
310 		bootx_add_chosen_props(base, mem_end);
311 	if (node == bootx_info->dispDeviceRegEntryOffset)
312 		bootx_add_display_props(base, mem_end);
313 
314 	/* do all our children */
315 	cpp = &np->child;
316 	while(*cpp) {
317 		np = (struct bootx_dt_node *)(base + *cpp);
318 		bootx_scan_dt_build_struct(base, *cpp, mem_end);
319 		cpp = &np->sibling;
320 	}
321 
322 	dt_push_token(OF_DT_END_NODE, mem_end);
323 }
324 
325 static unsigned long __init bootx_flatten_dt(unsigned long start)
326 {
327 	boot_infos_t *bi = bootx_info;
328 	unsigned long mem_start, mem_end;
329 	struct boot_param_header *hdr;
330 	unsigned long base;
331 	u64 *rsvmap;
332 
333 	/* Start using memory after the big blob passed by BootX, get
334 	 * some space for the header
335 	 */
336 	mem_start = mem_end = _ALIGN_UP(((unsigned long)bi) + start, 4);
337 	DBG("Boot params header at: %x\n", mem_start);
338 	hdr = (struct boot_param_header *)mem_start;
339 	mem_end += sizeof(struct boot_param_header);
340 	rsvmap = (u64 *)(_ALIGN_UP(mem_end, 8));
341 	hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - mem_start;
342 	mem_end = ((unsigned long)rsvmap) + 8 * sizeof(u64);
343 
344 	/* Get base of tree */
345 	base = ((unsigned long)bi) + bi->deviceTreeOffset;
346 
347 	/* Build string array */
348 	DBG("Building string array at: %x\n", mem_end);
349 	DBG("Device Tree Base=%x\n", base);
350 	bootx_dt_strbase = mem_end;
351 	mem_end += 4;
352 	bootx_dt_strend = mem_end;
353 	bootx_scan_dt_build_strings(base, 4, &mem_end);
354 	hdr->off_dt_strings = bootx_dt_strbase - mem_start;
355 	hdr->dt_strings_size = bootx_dt_strend - bootx_dt_strbase;
356 
357 	/* Build structure */
358 	mem_end = _ALIGN(mem_end, 16);
359 	DBG("Building device tree structure at: %x\n", mem_end);
360 	hdr->off_dt_struct = mem_end - mem_start;
361 	bootx_scan_dt_build_struct(base, 4, &mem_end);
362 	dt_push_token(OF_DT_END, &mem_end);
363 
364 	/* Finish header */
365 	hdr->boot_cpuid_phys = 0;
366 	hdr->magic = OF_DT_HEADER;
367 	hdr->totalsize = mem_end - mem_start;
368 	hdr->version = OF_DT_VERSION;
369 	/* Version 16 is not backward compatible */
370 	hdr->last_comp_version = 0x10;
371 
372 	/* Reserve the whole thing and copy the reserve map in, we
373 	 * also bump mem_reserve_cnt to cause further reservations to
374 	 * fail since it's too late.
375 	 */
376 	mem_end = _ALIGN(mem_end, PAGE_SIZE);
377 	DBG("End of boot params: %x\n", mem_end);
378 	rsvmap[0] = mem_start;
379 	rsvmap[1] = mem_end;
380 	rsvmap[2] = 0;
381 	rsvmap[3] = 0;
382 
383 	return (unsigned long)hdr;
384 }
385 
386 
387 #ifdef CONFIG_BOOTX_TEXT
388 static void __init btext_welcome(boot_infos_t *bi)
389 {
390 	unsigned long flags;
391 	unsigned long pvr;
392 
393 	bootx_printf("Welcome to Linux, kernel " UTS_RELEASE "\n");
394 	bootx_printf("\nlinked at        : 0x%x", KERNELBASE);
395 	bootx_printf("\nframe buffer at  : 0x%x", bi->dispDeviceBase);
396 	bootx_printf(" (phys), 0x%x", bi->logicalDisplayBase);
397 	bootx_printf(" (log)");
398 	bootx_printf("\nklimit           : 0x%x",(unsigned long)klimit);
399 	bootx_printf("\nboot_info at     : 0x%x", bi);
400 	__asm__ __volatile__ ("mfmsr %0" : "=r" (flags));
401 	bootx_printf("\nMSR              : 0x%x", flags);
402 	__asm__ __volatile__ ("mfspr %0, 287" : "=r" (pvr));
403 	bootx_printf("\nPVR              : 0x%x", pvr);
404 	pvr >>= 16;
405 	if (pvr > 1) {
406 	    __asm__ __volatile__ ("mfspr %0, 1008" : "=r" (flags));
407 	    bootx_printf("\nHID0             : 0x%x", flags);
408 	}
409 	if (pvr == 8 || pvr == 12 || pvr == 0x800c) {
410 	    __asm__ __volatile__ ("mfspr %0, 1019" : "=r" (flags));
411 	    bootx_printf("\nICTC             : 0x%x", flags);
412 	}
413 #ifdef DEBUG
414 	bootx_printf("\n\n");
415 	bootx_printf("bi->deviceTreeOffset   : 0x%x\n",
416 		     bi->deviceTreeOffset);
417 	bootx_printf("bi->deviceTreeSize     : 0x%x\n",
418 		     bi->deviceTreeSize);
419 #endif
420 	bootx_printf("\n\n");
421 }
422 #endif /* CONFIG_BOOTX_TEXT */
423 
424 void __init bootx_init(unsigned long r3, unsigned long r4)
425 {
426 	boot_infos_t *bi = (boot_infos_t *) r4;
427 	unsigned long hdr;
428 	unsigned long space;
429 	unsigned long ptr, x;
430 	char *model;
431 	unsigned long offset = reloc_offset();
432 
433 	reloc_got2(offset);
434 
435 	bootx_info = bi;
436 
437 	/* We haven't cleared any bss at this point, make sure
438 	 * what we need is initialized
439 	 */
440 	bootx_dt_strbase = bootx_dt_strend = 0;
441 	bootx_node_chosen = 0;
442 	bootx_disp_path[0] = 0;
443 
444 	if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
445 		bi->logicalDisplayBase = bi->dispDeviceBase;
446 
447 #ifdef CONFIG_BOOTX_TEXT
448 	btext_setup_display(bi->dispDeviceRect[2] - bi->dispDeviceRect[0],
449 			    bi->dispDeviceRect[3] - bi->dispDeviceRect[1],
450 			    bi->dispDeviceDepth, bi->dispDeviceRowBytes,
451 			    (unsigned long)bi->logicalDisplayBase);
452 	btext_clearscreen();
453 	btext_flushscreen();
454 #endif /* CONFIG_BOOTX_TEXT */
455 
456 	/*
457 	 * Test if boot-info is compatible.  Done only in config
458 	 * CONFIG_BOOTX_TEXT since there is nothing much we can do
459 	 * with an incompatible version, except display a message
460 	 * and eventually hang the processor...
461 	 *
462 	 * I'll try to keep enough of boot-info compatible in the
463 	 * future to always allow display of this message;
464 	 */
465 	if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
466 		bootx_printf(" !!! WARNING - Incompatible version"
467 			     " of BootX !!!\n\n\n");
468 		for (;;)
469 			;
470 	}
471 	if (bi->architecture != BOOT_ARCH_PCI) {
472 		bootx_printf(" !!! WARNING - Usupported machine"
473 			     " architecture !\n");
474 		for (;;)
475 			;
476 	}
477 
478 #ifdef CONFIG_BOOTX_TEXT
479 	btext_welcome(bi);
480 #endif
481 	/* New BootX enters kernel with MMU off, i/os are not allowed
482 	 * here. This hack will have been done by the boostrap anyway.
483 	 */
484 	if (bi->version < 4) {
485 		/*
486 		 * XXX If this is an iMac, turn off the USB controller.
487 		 */
488 		model = (char *) bootx_early_getprop(r4 + bi->deviceTreeOffset,
489 						     4, "model");
490 		if (model
491 		    && (strcmp(model, "iMac,1") == 0
492 			|| strcmp(model, "PowerMac1,1") == 0)) {
493 			bootx_printf("iMac,1 detected, shutting down USB \n");
494 			out_le32((unsigned __iomem *)0x80880008, 1);	/* XXX */
495 		}
496 	}
497 
498 	/* Get a pointer that points above the device tree, args, ramdisk,
499 	 * etc... to use for generating the flattened tree
500 	 */
501 	if (bi->version < 5) {
502 		space = bi->deviceTreeOffset + bi->deviceTreeSize;
503 		if (bi->ramDisk)
504 			space = bi->ramDisk + bi->ramDiskSize;
505 	} else
506 		space = bi->totalParamsSize;
507 
508 	bootx_printf("Total space used by parameters & ramdisk: %x \n", space);
509 
510 	/* New BootX will have flushed all TLBs and enters kernel with
511 	 * MMU switched OFF, so this should not be useful anymore.
512 	 */
513 	if (bi->version < 4) {
514 		bootx_printf("Touching pages...\n");
515 
516 		/*
517 		 * Touch each page to make sure the PTEs for them
518 		 * are in the hash table - the aim is to try to avoid
519 		 * getting DSI exceptions while copying the kernel image.
520 		 */
521 		for (ptr = ((unsigned long) &_stext) & PAGE_MASK;
522 		     ptr < (unsigned long)bi + space; ptr += PAGE_SIZE)
523 			x = *(volatile unsigned long *)ptr;
524 	}
525 
526 	/* Ok, now we need to generate a flattened device-tree to pass
527 	 * to the kernel
528 	 */
529 	bootx_printf("Preparing boot params...\n");
530 
531 	hdr = bootx_flatten_dt(space);
532 
533 #ifdef CONFIG_BOOTX_TEXT
534 #ifdef SET_BOOT_BAT
535 	bootx_printf("Preparing BAT...\n");
536 	btext_prepare_BAT();
537 #else
538 	btext_unmap();
539 #endif
540 #endif
541 
542 	reloc_got2(-offset);
543 
544 	__start(hdr, KERNELBASE + offset, 0);
545 }
546