xref: /linux/arch/powerpc/platforms/powermac/bootx_init.c (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Early boot support code for BootX bootloader
4  *
5  *  Copyright (C) 2005 Ben. Herrenschmidt (benh@kernel.crashing.org)
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/string.h>
10 #include <linux/init.h>
11 #include <linux/of_fdt.h>
12 #include <generated/utsrelease.h>
13 #include <asm/sections.h>
14 #include <asm/prom.h>
15 #include <asm/page.h>
16 #include <asm/bootx.h>
17 #include <asm/btext.h>
18 #include <asm/io.h>
19 #include <asm/setup.h>
20 
21 #undef DEBUG
22 #define SET_BOOT_BAT
23 
24 #ifdef DEBUG
25 #define DBG(fmt...) do { bootx_printf(fmt); } while(0)
26 #else
27 #define DBG(fmt...) do { } while(0)
28 #endif
29 
30 extern void __start(unsigned long r3, unsigned long r4, unsigned long r5);
31 
32 static unsigned long __initdata bootx_dt_strbase;
33 static unsigned long __initdata bootx_dt_strend;
34 static unsigned long __initdata bootx_node_chosen;
35 static boot_infos_t * __initdata bootx_info;
36 static char __initdata bootx_disp_path[256];
37 
38 /* Is boot-info compatible ? */
39 #define BOOT_INFO_IS_COMPATIBLE(bi) \
40 	((bi)->compatible_version <= BOOT_INFO_VERSION)
41 #define BOOT_INFO_IS_V2_COMPATIBLE(bi)	((bi)->version >= 2)
42 #define BOOT_INFO_IS_V4_COMPATIBLE(bi)	((bi)->version >= 4)
43 
44 #ifdef CONFIG_BOOTX_TEXT
45 static void __init bootx_printf(const char *format, ...)
46 {
47 	const char *p, *q, *s;
48 	va_list args;
49 	unsigned long v;
50 
51 	va_start(args, format);
52 	for (p = format; *p != 0; p = q) {
53 		for (q = p; *q != 0 && *q != '\n' && *q != '%'; ++q)
54 			;
55 		if (q > p)
56 			btext_drawtext(p, q - p);
57 		if (*q == 0)
58 			break;
59 		if (*q == '\n') {
60 			++q;
61 			btext_flushline();
62 			btext_drawstring("\r\n");
63 			btext_flushline();
64 			continue;
65 		}
66 		++q;
67 		if (*q == 0)
68 			break;
69 		switch (*q) {
70 		case 's':
71 			++q;
72 			s = va_arg(args, const char *);
73 			if (s == NULL)
74 				s = "<NULL>";
75 			btext_drawstring(s);
76 			break;
77 		case 'x':
78 			++q;
79 			v = va_arg(args, unsigned long);
80 			btext_drawhex(v);
81 			break;
82 		}
83 	}
84 	va_end(args);
85 }
86 #else /* CONFIG_BOOTX_TEXT */
87 static void __init bootx_printf(const char *format, ...) {}
88 #endif /* CONFIG_BOOTX_TEXT */
89 
90 static void * __init bootx_early_getprop(unsigned long base,
91 					 unsigned long node,
92 					 char *prop)
93 {
94 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
95 	u32 *ppp = &np->properties;
96 
97 	while(*ppp) {
98 		struct bootx_dt_prop *pp =
99 			(struct bootx_dt_prop *)(base + *ppp);
100 
101 		if (strcmp((char *)((unsigned long)pp->name + base),
102 			   prop) == 0) {
103 			return (void *)((unsigned long)pp->value + base);
104 		}
105 		ppp = &pp->next;
106 	}
107 	return NULL;
108 }
109 
110 #define dt_push_token(token, mem) \
111 	do { \
112 		*(mem) = ALIGN(*(mem),4); \
113 		*((u32 *)*(mem)) = token; \
114 		*(mem) += 4; \
115 	} while(0)
116 
117 static unsigned long __init bootx_dt_find_string(char *str)
118 {
119 	char *s, *os;
120 
121 	s = os = (char *)bootx_dt_strbase;
122 	s += 4;
123 	while (s <  (char *)bootx_dt_strend) {
124 		if (strcmp(s, str) == 0)
125 			return s - os;
126 		s += strlen(s) + 1;
127 	}
128 	return 0;
129 }
130 
131 static void __init bootx_dt_add_prop(char *name, void *data, int size,
132 				  unsigned long *mem_end)
133 {
134 	unsigned long soff = bootx_dt_find_string(name);
135 	if (data == NULL)
136 		size = 0;
137 	if (soff == 0) {
138 		bootx_printf("WARNING: Can't find string index for <%s>\n",
139 			     name);
140 		return;
141 	}
142 	if (size > 0x20000) {
143 		bootx_printf("WARNING: ignoring large property ");
144 		bootx_printf("%s length 0x%x\n", name, size);
145 		return;
146 	}
147 	dt_push_token(OF_DT_PROP, mem_end);
148 	dt_push_token(size, mem_end);
149 	dt_push_token(soff, mem_end);
150 
151 	/* push property content */
152 	if (size && data) {
153 		memcpy((void *)*mem_end, data, size);
154 		*mem_end = ALIGN(*mem_end + size, 4);
155 	}
156 }
157 
158 static void __init bootx_add_chosen_props(unsigned long base,
159 					  unsigned long *mem_end)
160 {
161 	u32 val;
162 
163 	bootx_dt_add_prop("linux,bootx", NULL, 0, mem_end);
164 
165 	if (bootx_info->kernelParamsOffset) {
166 		char *args = (char *)((unsigned long)bootx_info) +
167 			bootx_info->kernelParamsOffset;
168 		bootx_dt_add_prop("bootargs", args, strlen(args) + 1, mem_end);
169 	}
170 	if (bootx_info->ramDisk) {
171 		val = ((unsigned long)bootx_info) + bootx_info->ramDisk;
172 		bootx_dt_add_prop("linux,initrd-start", &val, 4, mem_end);
173 		val += bootx_info->ramDiskSize;
174 		bootx_dt_add_prop("linux,initrd-end", &val, 4, mem_end);
175 	}
176 	if (strlen(bootx_disp_path))
177 		bootx_dt_add_prop("linux,stdout-path", bootx_disp_path,
178 				  strlen(bootx_disp_path) + 1, mem_end);
179 }
180 
181 static void __init bootx_add_display_props(unsigned long base,
182 					   unsigned long *mem_end,
183 					   int has_real_node)
184 {
185 	boot_infos_t *bi = bootx_info;
186 	u32 tmp;
187 
188 	if (has_real_node) {
189 		bootx_dt_add_prop("linux,boot-display", NULL, 0, mem_end);
190 		bootx_dt_add_prop("linux,opened", NULL, 0, mem_end);
191 	} else
192 		bootx_dt_add_prop("linux,bootx-noscreen", NULL, 0, mem_end);
193 
194 	tmp = bi->dispDeviceDepth;
195 	bootx_dt_add_prop("linux,bootx-depth", &tmp, 4, mem_end);
196 	tmp = bi->dispDeviceRect[2] - bi->dispDeviceRect[0];
197 	bootx_dt_add_prop("linux,bootx-width", &tmp, 4, mem_end);
198 	tmp = bi->dispDeviceRect[3] - bi->dispDeviceRect[1];
199 	bootx_dt_add_prop("linux,bootx-height", &tmp, 4, mem_end);
200 	tmp = bi->dispDeviceRowBytes;
201 	bootx_dt_add_prop("linux,bootx-linebytes", &tmp, 4, mem_end);
202 	tmp = (u32)bi->dispDeviceBase;
203 	if (tmp == 0)
204 		tmp = (u32)bi->logicalDisplayBase;
205 	tmp += bi->dispDeviceRect[1] * bi->dispDeviceRowBytes;
206 	tmp += bi->dispDeviceRect[0] * ((bi->dispDeviceDepth + 7) / 8);
207 	bootx_dt_add_prop("linux,bootx-addr", &tmp, 4, mem_end);
208 }
209 
210 static void __init bootx_dt_add_string(char *s, unsigned long *mem_end)
211 {
212 	unsigned int l = strlen(s) + 1;
213 	memcpy((void *)*mem_end, s, l);
214 	bootx_dt_strend = *mem_end = *mem_end + l;
215 }
216 
217 static void __init bootx_scan_dt_build_strings(unsigned long base,
218 					       unsigned long node,
219 					       unsigned long *mem_end)
220 {
221 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
222 	u32 *cpp, *ppp = &np->properties;
223 	unsigned long soff;
224 	char *namep;
225 
226 	/* Keep refs to known nodes */
227 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
228        	if (namep == NULL) {
229 		bootx_printf("Node without a full name !\n");
230 		namep = "";
231 	}
232 	DBG("* strings: %s\n", namep);
233 
234 	if (!strcmp(namep, "/chosen")) {
235 		DBG(" detected /chosen ! adding properties names !\n");
236 		bootx_dt_add_string("linux,bootx", mem_end);
237 		bootx_dt_add_string("linux,stdout-path", mem_end);
238 		bootx_dt_add_string("linux,initrd-start", mem_end);
239 		bootx_dt_add_string("linux,initrd-end", mem_end);
240 		bootx_dt_add_string("bootargs", mem_end);
241 		bootx_node_chosen = node;
242 	}
243 	if (node == bootx_info->dispDeviceRegEntryOffset) {
244 		DBG(" detected display ! adding properties names !\n");
245 		bootx_dt_add_string("linux,boot-display", mem_end);
246 		bootx_dt_add_string("linux,opened", mem_end);
247 		strscpy(bootx_disp_path, namep, sizeof(bootx_disp_path));
248 	}
249 
250 	/* get and store all property names */
251 	while (*ppp) {
252 		struct bootx_dt_prop *pp =
253 			(struct bootx_dt_prop *)(base + *ppp);
254 
255 		namep = pp->name ? (char *)(base + pp->name) : NULL;
256  		if (namep == NULL || strcmp(namep, "name") == 0)
257  			goto next;
258 		/* get/create string entry */
259 		soff = bootx_dt_find_string(namep);
260 		if (soff == 0)
261 			bootx_dt_add_string(namep, mem_end);
262 	next:
263 		ppp = &pp->next;
264 	}
265 
266 	/* do all our children */
267 	cpp = &np->child;
268 	while(*cpp) {
269 		np = (struct bootx_dt_node *)(base + *cpp);
270 		bootx_scan_dt_build_strings(base, *cpp, mem_end);
271 		cpp = &np->sibling;
272 	}
273 }
274 
275 static void __init bootx_scan_dt_build_struct(unsigned long base,
276 					      unsigned long node,
277 					      unsigned long *mem_end)
278 {
279 	struct bootx_dt_node *np = (struct bootx_dt_node *)(base + node);
280 	u32 *cpp, *ppp = &np->properties;
281 	char *namep, *p, *ep, *lp;
282 	int l;
283 
284 	dt_push_token(OF_DT_BEGIN_NODE, mem_end);
285 
286 	/* get the node's full name */
287 	namep = np->full_name ? (char *)(base + np->full_name) : NULL;
288 	if (namep == NULL)
289 		namep = "";
290 	l = strlen(namep);
291 
292 	DBG("* struct: %s\n", namep);
293 
294 	/* Fixup an Apple bug where they have bogus \0 chars in the
295 	 * middle of the path in some properties, and extract
296 	 * the unit name (everything after the last '/').
297 	 */
298 	memcpy((void *)*mem_end, namep, l + 1);
299 	namep = (char *)*mem_end;
300 	for (lp = p = namep, ep = namep + l; p < ep; p++) {
301 		if (*p == '/')
302 			lp = namep;
303 		else if (*p != 0)
304 			*lp++ = *p;
305 	}
306 	*lp = 0;
307 	*mem_end = ALIGN((unsigned long)lp + 1, 4);
308 
309 	/* get and store all properties */
310 	while (*ppp) {
311 		struct bootx_dt_prop *pp =
312 			(struct bootx_dt_prop *)(base + *ppp);
313 
314 		namep = pp->name ? (char *)(base + pp->name) : NULL;
315 		/* Skip "name" */
316  		if (namep == NULL || !strcmp(namep, "name"))
317  			goto next;
318 		/* Skip "bootargs" in /chosen too as we replace it */
319 		if (node == bootx_node_chosen && !strcmp(namep, "bootargs"))
320 			goto next;
321 
322 		/* push property head */
323 		bootx_dt_add_prop(namep,
324 				  pp->value ? (void *)(base + pp->value): NULL,
325 				  pp->length, mem_end);
326 	next:
327 		ppp = &pp->next;
328 	}
329 
330 	if (node == bootx_node_chosen) {
331 		bootx_add_chosen_props(base, mem_end);
332 		if (bootx_info->dispDeviceRegEntryOffset == 0)
333 			bootx_add_display_props(base, mem_end, 0);
334 	}
335 	else if (node == bootx_info->dispDeviceRegEntryOffset)
336 		bootx_add_display_props(base, mem_end, 1);
337 
338 	/* do all our children */
339 	cpp = &np->child;
340 	while(*cpp) {
341 		np = (struct bootx_dt_node *)(base + *cpp);
342 		bootx_scan_dt_build_struct(base, *cpp, mem_end);
343 		cpp = &np->sibling;
344 	}
345 
346 	dt_push_token(OF_DT_END_NODE, mem_end);
347 }
348 
349 static unsigned long __init bootx_flatten_dt(unsigned long start)
350 {
351 	boot_infos_t *bi = bootx_info;
352 	unsigned long mem_start, mem_end;
353 	struct boot_param_header *hdr;
354 	unsigned long base;
355 	u64 *rsvmap;
356 
357 	/* Start using memory after the big blob passed by BootX, get
358 	 * some space for the header
359 	 */
360 	mem_start = mem_end = ALIGN(((unsigned long)bi) + start, 4);
361 	DBG("Boot params header at: %x\n", mem_start);
362 	hdr = (struct boot_param_header *)mem_start;
363 	mem_end += sizeof(struct boot_param_header);
364 	rsvmap = (u64 *)(ALIGN(mem_end, 8));
365 	hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - mem_start;
366 	mem_end = ((unsigned long)rsvmap) + 8 * sizeof(u64);
367 
368 	/* Get base of tree */
369 	base = ((unsigned long)bi) + bi->deviceTreeOffset;
370 
371 	/* Build string array */
372 	DBG("Building string array at: %x\n", mem_end);
373 	DBG("Device Tree Base=%x\n", base);
374 	bootx_dt_strbase = mem_end;
375 	mem_end += 4;
376 	bootx_dt_strend = mem_end;
377 	bootx_scan_dt_build_strings(base, 4, &mem_end);
378 	/* Add some strings */
379 	bootx_dt_add_string("linux,bootx-noscreen", &mem_end);
380 	bootx_dt_add_string("linux,bootx-depth", &mem_end);
381 	bootx_dt_add_string("linux,bootx-width", &mem_end);
382 	bootx_dt_add_string("linux,bootx-height", &mem_end);
383 	bootx_dt_add_string("linux,bootx-linebytes", &mem_end);
384 	bootx_dt_add_string("linux,bootx-addr", &mem_end);
385 	/* Wrap up strings */
386 	hdr->off_dt_strings = bootx_dt_strbase - mem_start;
387 	hdr->dt_strings_size = bootx_dt_strend - bootx_dt_strbase;
388 
389 	/* Build structure */
390 	mem_end = ALIGN(mem_end, 16);
391 	DBG("Building device tree structure at: %x\n", mem_end);
392 	hdr->off_dt_struct = mem_end - mem_start;
393 	bootx_scan_dt_build_struct(base, 4, &mem_end);
394 	dt_push_token(OF_DT_END, &mem_end);
395 
396 	/* Finish header */
397 	hdr->boot_cpuid_phys = 0;
398 	hdr->magic = OF_DT_HEADER;
399 	hdr->totalsize = mem_end - mem_start;
400 	hdr->version = OF_DT_VERSION;
401 	/* Version 16 is not backward compatible */
402 	hdr->last_comp_version = 0x10;
403 
404 	/* Reserve the whole thing and copy the reserve map in, we
405 	 * also bump mem_reserve_cnt to cause further reservations to
406 	 * fail since it's too late.
407 	 */
408 	mem_end = ALIGN(mem_end, PAGE_SIZE);
409 	DBG("End of boot params: %x\n", mem_end);
410 	rsvmap[0] = mem_start;
411 	rsvmap[1] = mem_end;
412 	if (bootx_info->ramDisk) {
413 		rsvmap[2] = ((unsigned long)bootx_info) + bootx_info->ramDisk;
414 		rsvmap[3] = rsvmap[2] + bootx_info->ramDiskSize;
415 		rsvmap[4] = 0;
416 		rsvmap[5] = 0;
417 	} else {
418 		rsvmap[2] = 0;
419 		rsvmap[3] = 0;
420 	}
421 
422 	return (unsigned long)hdr;
423 }
424 
425 
426 #ifdef CONFIG_BOOTX_TEXT
427 static void __init btext_welcome(boot_infos_t *bi)
428 {
429 	unsigned long flags;
430 	unsigned long pvr;
431 
432 	bootx_printf("Welcome to Linux, kernel " UTS_RELEASE "\n");
433 	bootx_printf("\nlinked at        : 0x%x", KERNELBASE);
434 	bootx_printf("\nframe buffer at  : 0x%x", bi->dispDeviceBase);
435 	bootx_printf(" (phys), 0x%x", bi->logicalDisplayBase);
436 	bootx_printf(" (log)");
437 	bootx_printf("\nklimit           : 0x%x",(unsigned long)_end);
438 	bootx_printf("\nboot_info at     : 0x%x", bi);
439 	__asm__ __volatile__ ("mfmsr %0" : "=r" (flags));
440 	bootx_printf("\nMSR              : 0x%x", flags);
441 	__asm__ __volatile__ ("mfspr %0, 287" : "=r" (pvr));
442 	bootx_printf("\nPVR              : 0x%x", pvr);
443 	pvr >>= 16;
444 	if (pvr > 1) {
445 	    __asm__ __volatile__ ("mfspr %0, 1008" : "=r" (flags));
446 	    bootx_printf("\nHID0             : 0x%x", flags);
447 	}
448 	if (pvr == 8 || pvr == 12 || pvr == 0x800c) {
449 	    __asm__ __volatile__ ("mfspr %0, 1019" : "=r" (flags));
450 	    bootx_printf("\nICTC             : 0x%x", flags);
451 	}
452 #ifdef DEBUG
453 	bootx_printf("\n\n");
454 	bootx_printf("bi->deviceTreeOffset   : 0x%x\n",
455 		     bi->deviceTreeOffset);
456 	bootx_printf("bi->deviceTreeSize     : 0x%x\n",
457 		     bi->deviceTreeSize);
458 #endif
459 	bootx_printf("\n\n");
460 }
461 #endif /* CONFIG_BOOTX_TEXT */
462 
463 void __init bootx_init(unsigned long r3, unsigned long r4)
464 {
465 	boot_infos_t *bi = (boot_infos_t *) r4;
466 	unsigned long hdr;
467 	unsigned long space;
468 	unsigned long ptr;
469 	char *model;
470 	unsigned long offset = reloc_offset();
471 
472 	reloc_got2(offset);
473 
474 	bootx_info = bi;
475 
476 	/* We haven't cleared any bss at this point, make sure
477 	 * what we need is initialized
478 	 */
479 	bootx_dt_strbase = bootx_dt_strend = 0;
480 	bootx_node_chosen = 0;
481 	bootx_disp_path[0] = 0;
482 
483 	if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
484 		bi->logicalDisplayBase = bi->dispDeviceBase;
485 
486 	/* Fixup depth 16 -> 15 as that's what MacOS calls 16bpp */
487 	if (bi->dispDeviceDepth == 16)
488 		bi->dispDeviceDepth = 15;
489 
490 
491 #ifdef CONFIG_BOOTX_TEXT
492 	ptr = (unsigned long)bi->logicalDisplayBase;
493 	ptr += bi->dispDeviceRect[1] * bi->dispDeviceRowBytes;
494 	ptr += bi->dispDeviceRect[0] * ((bi->dispDeviceDepth + 7) / 8);
495 	btext_setup_display(bi->dispDeviceRect[2] - bi->dispDeviceRect[0],
496 			    bi->dispDeviceRect[3] - bi->dispDeviceRect[1],
497 			    bi->dispDeviceDepth, bi->dispDeviceRowBytes,
498 			    (unsigned long)bi->logicalDisplayBase);
499 	btext_clearscreen();
500 	btext_flushscreen();
501 #endif /* CONFIG_BOOTX_TEXT */
502 
503 	/*
504 	 * Test if boot-info is compatible.  Done only in config
505 	 * CONFIG_BOOTX_TEXT since there is nothing much we can do
506 	 * with an incompatible version, except display a message
507 	 * and eventually hang the processor...
508 	 *
509 	 * I'll try to keep enough of boot-info compatible in the
510 	 * future to always allow display of this message;
511 	 */
512 	if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
513 		bootx_printf(" !!! WARNING - Incompatible version"
514 			     " of BootX !!!\n\n\n");
515 		for (;;)
516 			;
517 	}
518 	if (bi->architecture != BOOT_ARCH_PCI) {
519 		bootx_printf(" !!! WARNING - Unsupported machine"
520 			     " architecture !\n");
521 		for (;;)
522 			;
523 	}
524 
525 #ifdef CONFIG_BOOTX_TEXT
526 	btext_welcome(bi);
527 #endif
528 
529 	/* New BootX enters kernel with MMU off, i/os are not allowed
530 	 * here. This hack will have been done by the boostrap anyway.
531 	 */
532 	if (bi->version < 4) {
533 		/*
534 		 * XXX If this is an iMac, turn off the USB controller.
535 		 */
536 		model = (char *) bootx_early_getprop(r4 + bi->deviceTreeOffset,
537 						     4, "model");
538 		if (model
539 		    && (strcmp(model, "iMac,1") == 0
540 			|| strcmp(model, "PowerMac1,1") == 0)) {
541 			bootx_printf("iMac,1 detected, shutting down USB\n");
542 			out_le32((unsigned __iomem *)0x80880008, 1);	/* XXX */
543 		}
544 	}
545 
546 	/* Get a pointer that points above the device tree, args, ramdisk,
547 	 * etc... to use for generating the flattened tree
548 	 */
549 	if (bi->version < 5) {
550 		space = bi->deviceTreeOffset + bi->deviceTreeSize;
551 		if (bi->ramDisk >= space)
552 			space = bi->ramDisk + bi->ramDiskSize;
553 	} else
554 		space = bi->totalParamsSize;
555 
556 	bootx_printf("Total space used by parameters & ramdisk: 0x%x\n", space);
557 
558 	/* New BootX will have flushed all TLBs and enters kernel with
559 	 * MMU switched OFF, so this should not be useful anymore.
560 	 */
561 	if (bi->version < 4) {
562 		unsigned long x __maybe_unused;
563 
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