xref: /linux-6.15/arch/mips/kernel/setup.c (revision 4dbed85a)
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  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/cache.h>
28 #include <asm/cpu.h>
29 #include <asm/sections.h>
30 #include <asm/setup.h>
31 #include <asm/system.h>
32 
33 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
34 
35 EXPORT_SYMBOL(cpu_data);
36 
37 #ifdef CONFIG_VT
38 struct screen_info screen_info;
39 #endif
40 
41 /*
42  * Despite it's name this variable is even if we don't have PCI
43  */
44 unsigned int PCI_DMA_BUS_IS_PHYS;
45 
46 EXPORT_SYMBOL(PCI_DMA_BUS_IS_PHYS);
47 
48 /*
49  * Setup information
50  *
51  * These are initialized so they are in the .data section
52  */
53 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
54 
55 EXPORT_SYMBOL(mips_machtype);
56 
57 struct boot_mem_map boot_mem_map;
58 
59 static char command_line[CL_SIZE];
60        char arcs_cmdline[CL_SIZE]=CONFIG_CMDLINE;
61 
62 /*
63  * mips_io_port_base is the begin of the address space to which x86 style
64  * I/O ports are mapped.
65  */
66 const unsigned long mips_io_port_base __read_mostly = -1;
67 EXPORT_SYMBOL(mips_io_port_base);
68 
69 /*
70  * isa_slot_offset is the address where E(ISA) busaddress 0 is mapped
71  * for the processor.
72  */
73 unsigned long isa_slot_offset;
74 EXPORT_SYMBOL(isa_slot_offset);
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 		printk("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 		printk("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(" 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("(usable)\n");
123 			break;
124 		case BOOT_MEM_ROM_DATA:
125 			printk("(ROM data)\n");
126 			break;
127 		case BOOT_MEM_RESERVED:
128 			printk("(reserved)\n");
129 			break;
130 		default:
131 			printk("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 	u32 *initrd_header;
169 
170 	/*
171 	 * Board specific code or command line parser should have
172 	 * already set up initrd_start and initrd_end. In these cases
173 	 * perfom sanity checks and use them if all looks good.
174 	 */
175 	if (initrd_start && initrd_end > initrd_start)
176 		goto sanitize;
177 
178 	/*
179 	 * See if initrd has been added to the kernel image by
180 	 * arch/mips/boot/addinitrd.c. In that case a header is
181 	 * prepended to initrd and is made up by 8 bytes. The fisrt
182 	 * word is a magic number and the second one is the size of
183 	 * initrd.  Initrd start must be page aligned in any cases.
184 	 */
185 	initrd_header = __va(PAGE_ALIGN(__pa_symbol(&_end) + 8)) - 8;
186 	if (initrd_header[0] != 0x494E5244)
187 		goto disable;
188 	initrd_start = (unsigned long)(initrd_header + 2);
189 	initrd_end = initrd_start + initrd_header[1];
190 
191 sanitize:
192 	if (initrd_start & ~PAGE_MASK) {
193 		printk(KERN_ERR "initrd start must be page aligned\n");
194 		goto disable;
195 	}
196 	if (initrd_start < PAGE_OFFSET) {
197 		printk(KERN_ERR "initrd start < PAGE_OFFSET\n");
198 		goto disable;
199 	}
200 
201 	/*
202 	 * Sanitize initrd addresses. For example firmware
203 	 * can't guess if they need to pass them through
204 	 * 64-bits values if the kernel has been built in pure
205 	 * 32-bit. We need also to switch from KSEG0 to XKPHYS
206 	 * addresses now, so the code can now safely use __pa().
207 	 */
208 	end = __pa(initrd_end);
209 	initrd_end = (unsigned long)__va(end);
210 	initrd_start = (unsigned long)__va(__pa(initrd_start));
211 
212 	ROOT_DEV = Root_RAM0;
213 	return PFN_UP(end);
214 disable:
215 	initrd_start = 0;
216 	initrd_end = 0;
217 	return 0;
218 }
219 
220 static void __init finalize_initrd(void)
221 {
222 	unsigned long size = initrd_end - initrd_start;
223 
224 	if (size == 0) {
225 		printk(KERN_INFO "Initrd not found or empty");
226 		goto disable;
227 	}
228 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
229 		printk("Initrd extends beyond end of memory");
230 		goto disable;
231 	}
232 
233 	reserve_bootmem(__pa(initrd_start), size);
234 	initrd_below_start_ok = 1;
235 
236 	printk(KERN_INFO "Initial ramdisk at: 0x%lx (%lu bytes)\n",
237 	       initrd_start, size);
238 	return;
239 disable:
240 	printk(" - disabling initrd\n");
241 	initrd_start = 0;
242 	initrd_end = 0;
243 }
244 
245 #else  /* !CONFIG_BLK_DEV_INITRD */
246 
247 static unsigned long __init init_initrd(void)
248 {
249 	return 0;
250 }
251 
252 #define finalize_initrd()	do {} while (0)
253 
254 #endif
255 
256 /*
257  * Initialize the bootmem allocator. It also setup initrd related data
258  * if needed.
259  */
260 #ifdef CONFIG_SGI_IP27
261 
262 static void __init bootmem_init(void)
263 {
264 	init_initrd();
265 	finalize_initrd();
266 }
267 
268 #else  /* !CONFIG_SGI_IP27 */
269 
270 static void __init bootmem_init(void)
271 {
272 	unsigned long init_begin, reserved_end;
273 	unsigned long mapstart = ~0UL;
274 	unsigned long bootmap_size;
275 	int i;
276 
277 	/*
278 	 * Init any data related to initrd. It's a nop if INITRD is
279 	 * not selected. Once that done we can determine the low bound
280 	 * of usable memory.
281 	 */
282 	reserved_end = max(init_initrd(), PFN_UP(__pa_symbol(&_end)));
283 
284 	/*
285 	 * max_low_pfn is not a number of pages. The number of pages
286 	 * of the system is given by 'max_low_pfn - min_low_pfn'.
287 	 */
288 	min_low_pfn = ~0UL;
289 	max_low_pfn = 0;
290 
291 	/*
292 	 * Find the highest page frame number we have available.
293 	 */
294 	for (i = 0; i < boot_mem_map.nr_map; i++) {
295 		unsigned long start, end;
296 
297 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
298 			continue;
299 
300 		start = PFN_UP(boot_mem_map.map[i].addr);
301 		end = PFN_DOWN(boot_mem_map.map[i].addr
302 				+ boot_mem_map.map[i].size);
303 
304 		if (end > max_low_pfn)
305 			max_low_pfn = end;
306 		if (start < min_low_pfn)
307 			min_low_pfn = start;
308 		if (end <= reserved_end)
309 			continue;
310 		if (start >= mapstart)
311 			continue;
312 		mapstart = max(reserved_end, start);
313 	}
314 
315 	if (min_low_pfn >= max_low_pfn)
316 		panic("Incorrect memory mapping !!!");
317 	if (min_low_pfn > ARCH_PFN_OFFSET) {
318 		printk(KERN_INFO
319 		       "Wasting %lu bytes for tracking %lu unused pages\n",
320 		       (min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
321 		       min_low_pfn - ARCH_PFN_OFFSET);
322 	} else if (min_low_pfn < ARCH_PFN_OFFSET) {
323 		printk(KERN_INFO
324 		       "%lu free pages won't be used\n",
325 		       ARCH_PFN_OFFSET - min_low_pfn);
326 	}
327 	min_low_pfn = ARCH_PFN_OFFSET;
328 
329 	/*
330 	 * Determine low and high memory ranges
331 	 */
332 	if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
333 #ifdef CONFIG_HIGHMEM
334 		highstart_pfn = PFN_DOWN(HIGHMEM_START);
335 		highend_pfn = max_low_pfn;
336 #endif
337 		max_low_pfn = PFN_DOWN(HIGHMEM_START);
338 	}
339 
340 	/*
341 	 * Initialize the boot-time allocator with low memory only.
342 	 */
343 	bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
344 					 min_low_pfn, max_low_pfn);
345 
346 
347 	init_begin = PFN_UP(__pa_symbol(&__init_begin));
348 	for (i = 0; i < boot_mem_map.nr_map; i++) {
349 		unsigned long start, end;
350 
351 		start = PFN_UP(boot_mem_map.map[i].addr);
352 		end = PFN_DOWN(boot_mem_map.map[i].addr
353 				+ boot_mem_map.map[i].size);
354 
355 		if (start <= init_begin)
356 			start = init_begin;
357 		if (start >= end)
358 			continue;
359 
360 #ifndef CONFIG_HIGHMEM
361 		if (end > max_low_pfn)
362 			end = max_low_pfn;
363 
364 		/*
365 		 * ... finally, is the area going away?
366 		 */
367 		if (end <= start)
368 			continue;
369 #endif
370 
371 		add_active_range(0, start, end);
372 	}
373 
374 	/*
375 	 * Register fully available low RAM pages with the bootmem allocator.
376 	 */
377 	for (i = 0; i < boot_mem_map.nr_map; i++) {
378 		unsigned long start, end, size;
379 
380 		/*
381 		 * Reserve usable memory.
382 		 */
383 		if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
384 			continue;
385 
386 		start = PFN_UP(boot_mem_map.map[i].addr);
387 		end   = PFN_DOWN(boot_mem_map.map[i].addr
388 				    + boot_mem_map.map[i].size);
389 		/*
390 		 * We are rounding up the start address of usable memory
391 		 * and at the end of the usable range downwards.
392 		 */
393 		if (start >= max_low_pfn)
394 			continue;
395 		if (start < reserved_end)
396 			start = reserved_end;
397 		if (end > max_low_pfn)
398 			end = max_low_pfn;
399 
400 		/*
401 		 * ... finally, is the area going away?
402 		 */
403 		if (end <= start)
404 			continue;
405 		size = end - start;
406 
407 		/* Register lowmem ranges */
408 		free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
409 		memory_present(0, start, end);
410 	}
411 
412 	/*
413 	 * Reserve the bootmap memory.
414 	 */
415 	reserve_bootmem(PFN_PHYS(mapstart), bootmap_size);
416 
417 	/*
418 	 * Reserve initrd memory if needed.
419 	 */
420 	finalize_initrd();
421 }
422 
423 #endif	/* CONFIG_SGI_IP27 */
424 
425 /*
426  * arch_mem_init - initialize memory managment subsystem
427  *
428  *  o plat_mem_setup() detects the memory configuration and will record detected
429  *    memory areas using add_memory_region.
430  *
431  * At this stage the memory configuration of the system is known to the
432  * kernel but generic memory managment system is still entirely uninitialized.
433  *
434  *  o bootmem_init()
435  *  o sparse_init()
436  *  o paging_init()
437  *
438  * At this stage the bootmem allocator is ready to use.
439  *
440  * NOTE: historically plat_mem_setup did the entire platform initialization.
441  *       This was rather impractical because it meant plat_mem_setup had to
442  * get away without any kind of memory allocator.  To keep old code from
443  * breaking plat_setup was just renamed to plat_setup and a second platform
444  * initialization hook for anything else was introduced.
445  */
446 
447 static int usermem __initdata = 0;
448 
449 static int __init early_parse_mem(char *p)
450 {
451 	unsigned long start, size;
452 
453 	/*
454 	 * If a user specifies memory size, we
455 	 * blow away any automatically generated
456 	 * size.
457 	 */
458 	if (usermem == 0) {
459 		boot_mem_map.nr_map = 0;
460 		usermem = 1;
461  	}
462 	start = 0;
463 	size = memparse(p, &p);
464 	if (*p == '@')
465 		start = memparse(p + 1, &p);
466 
467 	add_memory_region(start, size, BOOT_MEM_RAM);
468 	return 0;
469 }
470 early_param("mem", early_parse_mem);
471 
472 static void __init arch_mem_init(char **cmdline_p)
473 {
474 	extern void plat_mem_setup(void);
475 
476 	/* call board setup routine */
477 	plat_mem_setup();
478 
479 	printk("Determined physical RAM map:\n");
480 	print_memory_map();
481 
482 	strlcpy(command_line, arcs_cmdline, sizeof(command_line));
483 	strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
484 
485 	*cmdline_p = command_line;
486 
487 	parse_early_param();
488 
489 	if (usermem) {
490 		printk("User-defined physical RAM map:\n");
491 		print_memory_map();
492 	}
493 
494 	bootmem_init();
495 	sparse_init();
496 	paging_init();
497 }
498 
499 static void __init resource_init(void)
500 {
501 	int i;
502 
503 	if (UNCAC_BASE != IO_BASE)
504 		return;
505 
506 	code_resource.start = __pa_symbol(&_text);
507 	code_resource.end = __pa_symbol(&_etext) - 1;
508 	data_resource.start = __pa_symbol(&_etext);
509 	data_resource.end = __pa_symbol(&_edata) - 1;
510 
511 	/*
512 	 * Request address space for all standard RAM.
513 	 */
514 	for (i = 0; i < boot_mem_map.nr_map; i++) {
515 		struct resource *res;
516 		unsigned long start, end;
517 
518 		start = boot_mem_map.map[i].addr;
519 		end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
520 		if (start >= HIGHMEM_START)
521 			continue;
522 		if (end >= HIGHMEM_START)
523 			end = HIGHMEM_START - 1;
524 
525 		res = alloc_bootmem(sizeof(struct resource));
526 		switch (boot_mem_map.map[i].type) {
527 		case BOOT_MEM_RAM:
528 		case BOOT_MEM_ROM_DATA:
529 			res->name = "System RAM";
530 			break;
531 		case BOOT_MEM_RESERVED:
532 		default:
533 			res->name = "reserved";
534 		}
535 
536 		res->start = start;
537 		res->end = end;
538 
539 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
540 		request_resource(&iomem_resource, res);
541 
542 		/*
543 		 *  We don't know which RAM region contains kernel data,
544 		 *  so we try it repeatedly and let the resource manager
545 		 *  test it.
546 		 */
547 		request_resource(res, &code_resource);
548 		request_resource(res, &data_resource);
549 	}
550 }
551 
552 void __init setup_arch(char **cmdline_p)
553 {
554 	cpu_probe();
555 	prom_init();
556 
557 #ifdef CONFIG_EARLY_PRINTK
558 	{
559 		extern void setup_early_printk(void);
560 
561 		setup_early_printk();
562 	}
563 #endif
564 	cpu_report();
565 
566 #if defined(CONFIG_VT)
567 #if defined(CONFIG_VGA_CONSOLE)
568 	conswitchp = &vga_con;
569 #elif defined(CONFIG_DUMMY_CONSOLE)
570 	conswitchp = &dummy_con;
571 #endif
572 #endif
573 
574 	arch_mem_init(cmdline_p);
575 
576 	resource_init();
577 #ifdef CONFIG_SMP
578 	plat_smp_setup();
579 #endif
580 }
581 
582 static int __init fpu_disable(char *s)
583 {
584 	int i;
585 
586 	for (i = 0; i < NR_CPUS; i++)
587 		cpu_data[i].options &= ~MIPS_CPU_FPU;
588 
589 	return 1;
590 }
591 
592 __setup("nofpu", fpu_disable);
593 
594 static int __init dsp_disable(char *s)
595 {
596 	cpu_data[0].ases &= ~MIPS_ASE_DSP;
597 
598 	return 1;
599 }
600 
601 __setup("nodsp", dsp_disable);
602 
603 unsigned long kernelsp[NR_CPUS];
604 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
605 
606 #ifdef CONFIG_DEBUG_FS
607 struct dentry *mips_debugfs_dir;
608 static int __init debugfs_mips(void)
609 {
610 	struct dentry *d;
611 
612 	d = debugfs_create_dir("mips", NULL);
613 	if (IS_ERR(d))
614 		return PTR_ERR(d);
615 	mips_debugfs_dir = d;
616 	return 0;
617 }
618 arch_initcall(debugfs_mips);
619 #endif
620