xref: /openbmc/linux/arch/mips/kernel/setup.c (revision 4800cd83)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1995 Linus Torvalds
7  * Copyright (C) 1995 Waldorf Electronics
8  * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03  Ralf Baechle
9  * Copyright (C) 1996 Stoned Elipot
10  * Copyright (C) 1999 Silicon Graphics, Inc.
11  * Copyright (C) 2000, 2001, 2002, 2007  Maciej W. Rozycki
12  */
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/module.h>
16 #include <linux/screen_info.h>
17 #include <linux/bootmem.h>
18 #include <linux/initrd.h>
19 #include <linux/root_dev.h>
20 #include <linux/highmem.h>
21 #include <linux/console.h>
22 #include <linux/pfn.h>
23 #include <linux/debugfs.h>
24 
25 #include <asm/addrspace.h>
26 #include <asm/bootinfo.h>
27 #include <asm/bugs.h>
28 #include <asm/cache.h>
29 #include <asm/cpu.h>
30 #include <asm/sections.h>
31 #include <asm/setup.h>
32 #include <asm/smp-ops.h>
33 #include <asm/system.h>
34 #include <asm/prom.h>
35 
36 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
37 
38 EXPORT_SYMBOL(cpu_data);
39 
40 #ifdef CONFIG_VT
41 struct screen_info screen_info;
42 #endif
43 
44 /*
45  * Despite it's name this variable is even if we don't have PCI
46  */
47 unsigned int PCI_DMA_BUS_IS_PHYS;
48 
49 EXPORT_SYMBOL(PCI_DMA_BUS_IS_PHYS);
50 
51 /*
52  * Setup information
53  *
54  * These are initialized so they are in the .data section
55  */
56 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
57 
58 EXPORT_SYMBOL(mips_machtype);
59 
60 struct boot_mem_map boot_mem_map;
61 
62 static char __initdata command_line[COMMAND_LINE_SIZE];
63 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
64 
65 #ifdef CONFIG_CMDLINE_BOOL
66 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
67 #endif
68 
69 /*
70  * mips_io_port_base is the begin of the address space to which x86 style
71  * I/O ports are mapped.
72  */
73 const unsigned long mips_io_port_base = -1;
74 EXPORT_SYMBOL(mips_io_port_base);
75 
76 static struct resource code_resource = { .name = "Kernel code", };
77 static struct resource data_resource = { .name = "Kernel data", };
78 
79 void __init add_memory_region(phys_t start, phys_t size, long type)
80 {
81 	int x = boot_mem_map.nr_map;
82 	struct boot_mem_map_entry *prev = boot_mem_map.map + x - 1;
83 
84 	/* Sanity check */
85 	if (start + size < start) {
86 		pr_warning("Trying to add an invalid memory region, skipped\n");
87 		return;
88 	}
89 
90 	/*
91 	 * Try to merge with previous entry if any.  This is far less than
92 	 * perfect but is sufficient for most real world cases.
93 	 */
94 	if (x && prev->addr + prev->size == start && prev->type == type) {
95 		prev->size += size;
96 		return;
97 	}
98 
99 	if (x == BOOT_MEM_MAP_MAX) {
100 		pr_err("Ooops! Too many entries in the memory map!\n");
101 		return;
102 	}
103 
104 	boot_mem_map.map[x].addr = start;
105 	boot_mem_map.map[x].size = size;
106 	boot_mem_map.map[x].type = type;
107 	boot_mem_map.nr_map++;
108 }
109 
110 static void __init print_memory_map(void)
111 {
112 	int i;
113 	const int field = 2 * sizeof(unsigned long);
114 
115 	for (i = 0; i < boot_mem_map.nr_map; i++) {
116 		printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
117 		       field, (unsigned long long) boot_mem_map.map[i].size,
118 		       field, (unsigned long long) boot_mem_map.map[i].addr);
119 
120 		switch (boot_mem_map.map[i].type) {
121 		case BOOT_MEM_RAM:
122 			printk(KERN_CONT "(usable)\n");
123 			break;
124 		case BOOT_MEM_ROM_DATA:
125 			printk(KERN_CONT "(ROM data)\n");
126 			break;
127 		case BOOT_MEM_RESERVED:
128 			printk(KERN_CONT "(reserved)\n");
129 			break;
130 		default:
131 			printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
132 			break;
133 		}
134 	}
135 }
136 
137 /*
138  * Manage initrd
139  */
140 #ifdef CONFIG_BLK_DEV_INITRD
141 
142 static int __init rd_start_early(char *p)
143 {
144 	unsigned long start = memparse(p, &p);
145 
146 #ifdef CONFIG_64BIT
147 	/* Guess if the sign extension was forgotten by bootloader */
148 	if (start < XKPHYS)
149 		start = (int)start;
150 #endif
151 	initrd_start = start;
152 	initrd_end += start;
153 	return 0;
154 }
155 early_param("rd_start", rd_start_early);
156 
157 static int __init rd_size_early(char *p)
158 {
159 	initrd_end += memparse(p, &p);
160 	return 0;
161 }
162 early_param("rd_size", rd_size_early);
163 
164 /* it returns the next free pfn after initrd */
165 static unsigned long __init init_initrd(void)
166 {
167 	unsigned long end;
168 
169 	/*
170 	 * Board specific code or command line parser should have
171 	 * already set up initrd_start and initrd_end. In these cases
172 	 * perfom sanity checks and use them if all looks good.
173 	 */
174 	if (!initrd_start || initrd_end <= initrd_start)
175 		goto disable;
176 
177 	if (initrd_start & ~PAGE_MASK) {
178 		pr_err("initrd start must be page aligned\n");
179 		goto disable;
180 	}
181 	if (initrd_start < PAGE_OFFSET) {
182 		pr_err("initrd start < PAGE_OFFSET\n");
183 		goto disable;
184 	}
185 
186 	/*
187 	 * Sanitize initrd addresses. For example firmware
188 	 * can't guess if they need to pass them through
189 	 * 64-bits values if the kernel has been built in pure
190 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
191 	 * addresses now, so the code can now safely use __pa().
192 	 */
193 	end = __pa(initrd_end);
194 	initrd_end = (unsigned long)__va(end);
195 	initrd_start = (unsigned long)__va(__pa(initrd_start));
196 
197 	ROOT_DEV = Root_RAM0;
198 	return PFN_UP(end);
199 disable:
200 	initrd_start = 0;
201 	initrd_end = 0;
202 	return 0;
203 }
204 
205 static void __init finalize_initrd(void)
206 {
207 	unsigned long size = initrd_end - initrd_start;
208 
209 	if (size == 0) {
210 		printk(KERN_INFO "Initrd not found or empty");
211 		goto disable;
212 	}
213 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
214 		printk(KERN_ERR "Initrd extends beyond end of memory");
215 		goto disable;
216 	}
217 
218 	reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
219 	initrd_below_start_ok = 1;
220 
221 	pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
222 		initrd_start, size);
223 	return;
224 disable:
225 	printk(KERN_CONT " - disabling initrd\n");
226 	initrd_start = 0;
227 	initrd_end = 0;
228 }
229 
230 #else  /* !CONFIG_BLK_DEV_INITRD */
231 
232 static unsigned long __init init_initrd(void)
233 {
234 	return 0;
235 }
236 
237 #define finalize_initrd()	do {} while (0)
238 
239 #endif
240 
241 /*
242  * Initialize the bootmem allocator. It also setup initrd related data
243  * if needed.
244  */
245 #ifdef CONFIG_SGI_IP27
246 
247 static void __init bootmem_init(void)
248 {
249 	init_initrd();
250 	finalize_initrd();
251 }
252 
253 #else  /* !CONFIG_SGI_IP27 */
254 
255 static void __init bootmem_init(void)
256 {
257 	unsigned long reserved_end;
258 	unsigned long mapstart = ~0UL;
259 	unsigned long bootmap_size;
260 	int i;
261 
262 	/*
263 	 * Init any data related to initrd. It's a nop if INITRD is
264 	 * not selected. Once that done we can determine the low bound
265 	 * of usable memory.
266 	 */
267 	reserved_end = max(init_initrd(),
268 			   (unsigned long) PFN_UP(__pa_symbol(&_end)));
269 
270 	/*
271 	 * max_low_pfn is not a number of pages. The number of pages
272 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
273 	 */
274 	min_low_pfn = ~0UL;
275 	max_low_pfn = 0;
276 
277 	/*
278 	 * Find the highest page frame number we have available.
279 	 */
280 	for (i = 0; i < boot_mem_map.nr_map; i++) {
281 		unsigned long start, end;
282 
283 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
284 			continue;
285 
286 		start = PFN_UP(boot_mem_map.map[i].addr);
287 		end = PFN_DOWN(boot_mem_map.map[i].addr
288 				+ boot_mem_map.map[i].size);
289 
290 		if (end > max_low_pfn)
291 			max_low_pfn = end;
292 		if (start < min_low_pfn)
293 			min_low_pfn = start;
294 		if (end <= reserved_end)
295 			continue;
296 		if (start >= mapstart)
297 			continue;
298 		mapstart = max(reserved_end, start);
299 	}
300 
301 	if (min_low_pfn >= max_low_pfn)
302 		panic("Incorrect memory mapping !!!");
303 	if (min_low_pfn > ARCH_PFN_OFFSET) {
304 		pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
305 			(min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
306 			min_low_pfn - ARCH_PFN_OFFSET);
307 	} else if (min_low_pfn < ARCH_PFN_OFFSET) {
308 		pr_info("%lu free pages won't be used\n",
309 			ARCH_PFN_OFFSET - min_low_pfn);
310 	}
311 	min_low_pfn = ARCH_PFN_OFFSET;
312 
313 	/*
314 	 * Determine low and high memory ranges
315 	 */
316 	max_pfn = max_low_pfn;
317 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
318 #ifdef CONFIG_HIGHMEM
319 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
320 		highend_pfn = max_low_pfn;
321 #endif
322 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
323 	}
324 
325 	/*
326 	 * Initialize the boot-time allocator with low memory only.
327 	 */
328 	bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
329 					 min_low_pfn, max_low_pfn);
330 
331 
332 	for (i = 0; i < boot_mem_map.nr_map; i++) {
333 		unsigned long start, end;
334 
335 		start = PFN_UP(boot_mem_map.map[i].addr);
336 		end = PFN_DOWN(boot_mem_map.map[i].addr
337 				+ boot_mem_map.map[i].size);
338 
339 		if (start <= min_low_pfn)
340 			start = min_low_pfn;
341 		if (start >= end)
342 			continue;
343 
344 #ifndef CONFIG_HIGHMEM
345 		if (end > max_low_pfn)
346 			end = max_low_pfn;
347 
348 		/*
349 		 * ... finally, is the area going away?
350 		 */
351 		if (end <= start)
352 			continue;
353 #endif
354 
355 		add_active_range(0, start, end);
356 	}
357 
358 	/*
359 	 * Register fully available low RAM pages with the bootmem allocator.
360 	 */
361 	for (i = 0; i < boot_mem_map.nr_map; i++) {
362 		unsigned long start, end, size;
363 
364 		/*
365 		 * Reserve usable memory.
366 		 */
367 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
368 			continue;
369 
370 		start = PFN_UP(boot_mem_map.map[i].addr);
371 		end   = PFN_DOWN(boot_mem_map.map[i].addr
372 				    + boot_mem_map.map[i].size);
373 		/*
374 		 * We are rounding up the start address of usable memory
375 		 * and at the end of the usable range downwards.
376 		 */
377 		if (start >= max_low_pfn)
378 			continue;
379 		if (start < reserved_end)
380 			start = reserved_end;
381 		if (end > max_low_pfn)
382 			end = max_low_pfn;
383 
384 		/*
385 		 * ... finally, is the area going away?
386 		 */
387 		if (end <= start)
388 			continue;
389 		size = end - start;
390 
391 		/* Register lowmem ranges */
392 		free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
393 		memory_present(0, start, end);
394 	}
395 
396 	/*
397 	 * Reserve the bootmap memory.
398 	 */
399 	reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);
400 
401 	/*
402 	 * Reserve initrd memory if needed.
403 	 */
404 	finalize_initrd();
405 }
406 
407 #endif	/* CONFIG_SGI_IP27 */
408 
409 /*
410  * arch_mem_init - initialize memory management subsystem
411  *
412  *  o plat_mem_setup() detects the memory configuration and will record detected
413  *    memory areas using add_memory_region.
414  *
415  * At this stage the memory configuration of the system is known to the
416  * kernel but generic memory management system is still entirely uninitialized.
417  *
418  *  o bootmem_init()
419  *  o sparse_init()
420  *  o paging_init()
421  *
422  * At this stage the bootmem allocator is ready to use.
423  *
424  * NOTE: historically plat_mem_setup did the entire platform initialization.
425  *       This was rather impractical because it meant plat_mem_setup had to
426  * get away without any kind of memory allocator.  To keep old code from
427  * breaking plat_setup was just renamed to plat_setup and a second platform
428  * initialization hook for anything else was introduced.
429  */
430 
431 static int usermem __initdata;
432 
433 static int __init early_parse_mem(char *p)
434 {
435 	unsigned long start, size;
436 
437 	/*
438 	 * If a user specifies memory size, we
439 	 * blow away any automatically generated
440 	 * size.
441 	 */
442 	if (usermem == 0) {
443 		boot_mem_map.nr_map = 0;
444 		usermem = 1;
445  	}
446 	start = 0;
447 	size = memparse(p, &p);
448 	if (*p == '@')
449 		start = memparse(p + 1, &p);
450 
451 	add_memory_region(start, size, BOOT_MEM_RAM);
452 	return 0;
453 }
454 early_param("mem", early_parse_mem);
455 
456 static void __init arch_mem_init(char **cmdline_p)
457 {
458 	extern void plat_mem_setup(void);
459 
460 	/* call board setup routine */
461 	plat_mem_setup();
462 
463 	pr_info("Determined physical RAM map:\n");
464 	print_memory_map();
465 
466 #ifdef CONFIG_CMDLINE_BOOL
467 #ifdef CONFIG_CMDLINE_OVERRIDE
468 	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
469 #else
470 	if (builtin_cmdline[0]) {
471 		strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
472 		strlcat(arcs_cmdline, builtin_cmdline, COMMAND_LINE_SIZE);
473 	}
474 	strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
475 #endif
476 #else
477 	strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
478 #endif
479 	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
480 
481 	*cmdline_p = command_line;
482 
483 	parse_early_param();
484 
485 	if (usermem) {
486 		pr_info("User-defined physical RAM map:\n");
487 		print_memory_map();
488 	}
489 
490 	bootmem_init();
491 	device_tree_init();
492 	sparse_init();
493 	plat_swiotlb_setup();
494 	paging_init();
495 }
496 
497 static void __init resource_init(void)
498 {
499 	int i;
500 
501 	if (UNCAC_BASE != IO_BASE)
502 		return;
503 
504 	code_resource.start = __pa_symbol(&_text);
505 	code_resource.end = __pa_symbol(&_etext) - 1;
506 	data_resource.start = __pa_symbol(&_etext);
507 	data_resource.end = __pa_symbol(&_edata) - 1;
508 
509 	/*
510 	 * Request address space for all standard RAM.
511 	 */
512 	for (i = 0; i < boot_mem_map.nr_map; i++) {
513 		struct resource *res;
514 		unsigned long start, end;
515 
516 		start = boot_mem_map.map[i].addr;
517 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
518 		if (start >= HIGHMEM_START)
519 			continue;
520 		if (end >= HIGHMEM_START)
521 			end = HIGHMEM_START - 1;
522 
523 		res = alloc_bootmem(sizeof(struct resource));
524 		switch (boot_mem_map.map[i].type) {
525 		case BOOT_MEM_RAM:
526 		case BOOT_MEM_ROM_DATA:
527 			res->name = "System RAM";
528 			break;
529 		case BOOT_MEM_RESERVED:
530 		default:
531 			res->name = "reserved";
532 		}
533 
534 		res->start = start;
535 		res->end = end;
536 
537 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
538 		request_resource(&iomem_resource, res);
539 
540 		/*
541 		 *  We don't know which RAM region contains kernel data,
542 		 *  so we try it repeatedly and let the resource manager
543 		 *  test it.
544 		 */
545 		request_resource(res, &code_resource);
546 		request_resource(res, &data_resource);
547 	}
548 }
549 
550 void __init setup_arch(char **cmdline_p)
551 {
552 	cpu_probe();
553 	prom_init();
554 
555 #ifdef CONFIG_EARLY_PRINTK
556 	setup_early_printk();
557 #endif
558 	cpu_report();
559 	check_bugs_early();
560 
561 #if defined(CONFIG_VT)
562 #if defined(CONFIG_VGA_CONSOLE)
563 	conswitchp = &vga_con;
564 #elif defined(CONFIG_DUMMY_CONSOLE)
565 	conswitchp = &dummy_con;
566 #endif
567 #endif
568 
569 	arch_mem_init(cmdline_p);
570 
571 	resource_init();
572 	plat_smp_setup();
573 }
574 
575 unsigned long kernelsp[NR_CPUS];
576 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
577 
578 #ifdef CONFIG_DEBUG_FS
579 struct dentry *mips_debugfs_dir;
580 static int __init debugfs_mips(void)
581 {
582 	struct dentry *d;
583 
584 	d = debugfs_create_dir("mips", NULL);
585 	if (!d)
586 		return -ENOMEM;
587 	mips_debugfs_dir = d;
588 	return 0;
589 }
590 arch_initcall(debugfs_mips);
591 #endif
592