mm: page_alloc: do not treat a zone that cannot be used for dirty pages as "full"
[linux/fpc-iii.git] / arch / mips / kernel / setup.c
bloba842154d57dc466eaba000039b3fd5e436c6cb69
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.
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
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/export.h>
16 #include <linux/screen_info.h>
17 #include <linux/memblock.h>
18 #include <linux/bootmem.h>
19 #include <linux/initrd.h>
20 #include <linux/root_dev.h>
21 #include <linux/highmem.h>
22 #include <linux/console.h>
23 #include <linux/pfn.h>
24 #include <linux/debugfs.h>
25 #include <linux/kexec.h>
26 #include <linux/sizes.h>
28 #include <asm/addrspace.h>
29 #include <asm/bootinfo.h>
30 #include <asm/bugs.h>
31 #include <asm/cache.h>
32 #include <asm/cpu.h>
33 #include <asm/sections.h>
34 #include <asm/setup.h>
35 #include <asm/smp-ops.h>
36 #include <asm/prom.h>
38 struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
40 EXPORT_SYMBOL(cpu_data);
42 #ifdef CONFIG_VT
43 struct screen_info screen_info;
44 #endif
47 * Despite it's name this variable is even if we don't have PCI
49 unsigned int PCI_DMA_BUS_IS_PHYS;
51 EXPORT_SYMBOL(PCI_DMA_BUS_IS_PHYS);
54 * Setup information
56 * These are initialized so they are in the .data section
58 unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;
60 EXPORT_SYMBOL(mips_machtype);
62 struct boot_mem_map boot_mem_map;
64 static char __initdata command_line[COMMAND_LINE_SIZE];
65 char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
67 #ifdef CONFIG_CMDLINE_BOOL
68 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
69 #endif
72 * mips_io_port_base is the begin of the address space to which x86 style
73 * I/O ports are mapped.
75 const unsigned long mips_io_port_base = -1;
76 EXPORT_SYMBOL(mips_io_port_base);
78 static struct resource code_resource = { .name = "Kernel code", };
79 static struct resource data_resource = { .name = "Kernel data", };
81 static void *detect_magic __initdata = detect_memory_region;
83 void __init add_memory_region(phys_t start, phys_t size, long type)
85 int x = boot_mem_map.nr_map;
86 int i;
88 /* Sanity check */
89 if (start + size < start) {
90 pr_warning("Trying to add an invalid memory region, skipped\n");
91 return;
95 * Try to merge with existing entry, if any.
97 for (i = 0; i < boot_mem_map.nr_map; i++) {
98 struct boot_mem_map_entry *entry = boot_mem_map.map + i;
99 unsigned long top;
101 if (entry->type != type)
102 continue;
104 if (start + size < entry->addr)
105 continue; /* no overlap */
107 if (entry->addr + entry->size < start)
108 continue; /* no overlap */
110 top = max(entry->addr + entry->size, start + size);
111 entry->addr = min(entry->addr, start);
112 entry->size = top - entry->addr;
114 return;
117 if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
118 pr_err("Ooops! Too many entries in the memory map!\n");
119 return;
122 boot_mem_map.map[x].addr = start;
123 boot_mem_map.map[x].size = size;
124 boot_mem_map.map[x].type = type;
125 boot_mem_map.nr_map++;
128 void __init detect_memory_region(phys_t start, phys_t sz_min, phys_t sz_max)
130 void *dm = &detect_magic;
131 phys_t size;
133 for (size = sz_min; size < sz_max; size <<= 1) {
134 if (!memcmp(dm, dm + size, sizeof(detect_magic)))
135 break;
138 pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
139 ((unsigned long long) size) / SZ_1M,
140 (unsigned long long) start,
141 ((unsigned long long) sz_min) / SZ_1M,
142 ((unsigned long long) sz_max) / SZ_1M);
144 add_memory_region(start, size, BOOT_MEM_RAM);
147 static void __init print_memory_map(void)
149 int i;
150 const int field = 2 * sizeof(unsigned long);
152 for (i = 0; i < boot_mem_map.nr_map; i++) {
153 printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
154 field, (unsigned long long) boot_mem_map.map[i].size,
155 field, (unsigned long long) boot_mem_map.map[i].addr);
157 switch (boot_mem_map.map[i].type) {
158 case BOOT_MEM_RAM:
159 printk(KERN_CONT "(usable)\n");
160 break;
161 case BOOT_MEM_INIT_RAM:
162 printk(KERN_CONT "(usable after init)\n");
163 break;
164 case BOOT_MEM_ROM_DATA:
165 printk(KERN_CONT "(ROM data)\n");
166 break;
167 case BOOT_MEM_RESERVED:
168 printk(KERN_CONT "(reserved)\n");
169 break;
170 default:
171 printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
172 break;
178 * Manage initrd
180 #ifdef CONFIG_BLK_DEV_INITRD
182 static int __init rd_start_early(char *p)
184 unsigned long start = memparse(p, &p);
186 #ifdef CONFIG_64BIT
187 /* Guess if the sign extension was forgotten by bootloader */
188 if (start < XKPHYS)
189 start = (int)start;
190 #endif
191 initrd_start = start;
192 initrd_end += start;
193 return 0;
195 early_param("rd_start", rd_start_early);
197 static int __init rd_size_early(char *p)
199 initrd_end += memparse(p, &p);
200 return 0;
202 early_param("rd_size", rd_size_early);
204 /* it returns the next free pfn after initrd */
205 static unsigned long __init init_initrd(void)
207 unsigned long end;
210 * Board specific code or command line parser should have
211 * already set up initrd_start and initrd_end. In these cases
212 * perfom sanity checks and use them if all looks good.
214 if (!initrd_start || initrd_end <= initrd_start)
215 goto disable;
217 if (initrd_start & ~PAGE_MASK) {
218 pr_err("initrd start must be page aligned\n");
219 goto disable;
221 if (initrd_start < PAGE_OFFSET) {
222 pr_err("initrd start < PAGE_OFFSET\n");
223 goto disable;
227 * Sanitize initrd addresses. For example firmware
228 * can't guess if they need to pass them through
229 * 64-bits values if the kernel has been built in pure
230 * 32-bit. We need also to switch from KSEG0 to XKPHYS
231 * addresses now, so the code can now safely use __pa().
233 end = __pa(initrd_end);
234 initrd_end = (unsigned long)__va(end);
235 initrd_start = (unsigned long)__va(__pa(initrd_start));
237 ROOT_DEV = Root_RAM0;
238 return PFN_UP(end);
239 disable:
240 initrd_start = 0;
241 initrd_end = 0;
242 return 0;
245 static void __init finalize_initrd(void)
247 unsigned long size = initrd_end - initrd_start;
249 if (size == 0) {
250 printk(KERN_INFO "Initrd not found or empty");
251 goto disable;
253 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
254 printk(KERN_ERR "Initrd extends beyond end of memory");
255 goto disable;
258 reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
259 initrd_below_start_ok = 1;
261 pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
262 initrd_start, size);
263 return;
264 disable:
265 printk(KERN_CONT " - disabling initrd\n");
266 initrd_start = 0;
267 initrd_end = 0;
270 #else /* !CONFIG_BLK_DEV_INITRD */
272 static unsigned long __init init_initrd(void)
274 return 0;
277 #define finalize_initrd() do {} while (0)
279 #endif
282 * Initialize the bootmem allocator. It also setup initrd related data
283 * if needed.
285 #ifdef CONFIG_SGI_IP27
287 static void __init bootmem_init(void)
289 init_initrd();
290 finalize_initrd();
293 #else /* !CONFIG_SGI_IP27 */
295 static void __init bootmem_init(void)
297 unsigned long reserved_end;
298 unsigned long mapstart = ~0UL;
299 unsigned long bootmap_size;
300 int i;
303 * Sanity check any INITRD first. We don't take it into account
304 * for bootmem setup initially, rely on the end-of-kernel-code
305 * as our memory range starting point. Once bootmem is inited we
306 * will reserve the area used for the initrd.
308 init_initrd();
309 reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));
312 * max_low_pfn is not a number of pages. The number of pages
313 * of the system is given by 'max_low_pfn - min_low_pfn'.
315 min_low_pfn = ~0UL;
316 max_low_pfn = 0;
319 * Find the highest page frame number we have available.
321 for (i = 0; i < boot_mem_map.nr_map; i++) {
322 unsigned long start, end;
324 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
325 continue;
327 start = PFN_UP(boot_mem_map.map[i].addr);
328 end = PFN_DOWN(boot_mem_map.map[i].addr
329 + boot_mem_map.map[i].size);
331 if (end > max_low_pfn)
332 max_low_pfn = end;
333 if (start < min_low_pfn)
334 min_low_pfn = start;
335 if (end <= reserved_end)
336 continue;
337 if (start >= mapstart)
338 continue;
339 mapstart = max(reserved_end, start);
342 if (min_low_pfn >= max_low_pfn)
343 panic("Incorrect memory mapping !!!");
344 if (min_low_pfn > ARCH_PFN_OFFSET) {
345 pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
346 (min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
347 min_low_pfn - ARCH_PFN_OFFSET);
348 } else if (min_low_pfn < ARCH_PFN_OFFSET) {
349 pr_info("%lu free pages won't be used\n",
350 ARCH_PFN_OFFSET - min_low_pfn);
352 min_low_pfn = ARCH_PFN_OFFSET;
355 * Determine low and high memory ranges
357 max_pfn = max_low_pfn;
358 if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
359 #ifdef CONFIG_HIGHMEM
360 highstart_pfn = PFN_DOWN(HIGHMEM_START);
361 highend_pfn = max_low_pfn;
362 #endif
363 max_low_pfn = PFN_DOWN(HIGHMEM_START);
366 #ifdef CONFIG_BLK_DEV_INITRD
368 * mapstart should be after initrd_end
370 if (initrd_end)
371 mapstart = max(mapstart, (unsigned long)PFN_UP(__pa(initrd_end)));
372 #endif
375 * Initialize the boot-time allocator with low memory only.
377 bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
378 min_low_pfn, max_low_pfn);
381 for (i = 0; i < boot_mem_map.nr_map; i++) {
382 unsigned long start, end;
384 start = PFN_UP(boot_mem_map.map[i].addr);
385 end = PFN_DOWN(boot_mem_map.map[i].addr
386 + boot_mem_map.map[i].size);
388 if (start <= min_low_pfn)
389 start = min_low_pfn;
390 if (start >= end)
391 continue;
393 #ifndef CONFIG_HIGHMEM
394 if (end > max_low_pfn)
395 end = max_low_pfn;
398 * ... finally, is the area going away?
400 if (end <= start)
401 continue;
402 #endif
404 memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
408 * Register fully available low RAM pages with the bootmem allocator.
410 for (i = 0; i < boot_mem_map.nr_map; i++) {
411 unsigned long start, end, size;
413 start = PFN_UP(boot_mem_map.map[i].addr);
414 end = PFN_DOWN(boot_mem_map.map[i].addr
415 + boot_mem_map.map[i].size);
418 * Reserve usable memory.
420 switch (boot_mem_map.map[i].type) {
421 case BOOT_MEM_RAM:
422 break;
423 case BOOT_MEM_INIT_RAM:
424 memory_present(0, start, end);
425 continue;
426 default:
427 /* Not usable memory */
428 continue;
432 * We are rounding up the start address of usable memory
433 * and at the end of the usable range downwards.
435 if (start >= max_low_pfn)
436 continue;
437 if (start < reserved_end)
438 start = reserved_end;
439 if (end > max_low_pfn)
440 end = max_low_pfn;
443 * ... finally, is the area going away?
445 if (end <= start)
446 continue;
447 size = end - start;
449 /* Register lowmem ranges */
450 free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
451 memory_present(0, start, end);
455 * Reserve the bootmap memory.
457 reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);
460 * Reserve initrd memory if needed.
462 finalize_initrd();
465 #endif /* CONFIG_SGI_IP27 */
468 * arch_mem_init - initialize memory management subsystem
470 * o plat_mem_setup() detects the memory configuration and will record detected
471 * memory areas using add_memory_region.
473 * At this stage the memory configuration of the system is known to the
474 * kernel but generic memory management system is still entirely uninitialized.
476 * o bootmem_init()
477 * o sparse_init()
478 * o paging_init()
480 * At this stage the bootmem allocator is ready to use.
482 * NOTE: historically plat_mem_setup did the entire platform initialization.
483 * This was rather impractical because it meant plat_mem_setup had to
484 * get away without any kind of memory allocator. To keep old code from
485 * breaking plat_setup was just renamed to plat_setup and a second platform
486 * initialization hook for anything else was introduced.
489 static int usermem __initdata;
491 static int __init early_parse_mem(char *p)
493 unsigned long start, size;
496 * If a user specifies memory size, we
497 * blow away any automatically generated
498 * size.
500 if (usermem == 0) {
501 boot_mem_map.nr_map = 0;
502 usermem = 1;
504 start = 0;
505 size = memparse(p, &p);
506 if (*p == '@')
507 start = memparse(p + 1, &p);
509 add_memory_region(start, size, BOOT_MEM_RAM);
510 return 0;
512 early_param("mem", early_parse_mem);
514 #ifdef CONFIG_PROC_VMCORE
515 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
516 static int __init early_parse_elfcorehdr(char *p)
518 int i;
520 setup_elfcorehdr = memparse(p, &p);
522 for (i = 0; i < boot_mem_map.nr_map; i++) {
523 unsigned long start = boot_mem_map.map[i].addr;
524 unsigned long end = (boot_mem_map.map[i].addr +
525 boot_mem_map.map[i].size);
526 if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
528 * Reserve from the elf core header to the end of
529 * the memory segment, that should all be kdump
530 * reserved memory.
532 setup_elfcorehdr_size = end - setup_elfcorehdr;
533 break;
537 * If we don't find it in the memory map, then we shouldn't
538 * have to worry about it, as the new kernel won't use it.
540 return 0;
542 early_param("elfcorehdr", early_parse_elfcorehdr);
543 #endif
545 static void __init arch_mem_addpart(phys_t mem, phys_t end, int type)
547 phys_t size;
548 int i;
550 size = end - mem;
551 if (!size)
552 return;
554 /* Make sure it is in the boot_mem_map */
555 for (i = 0; i < boot_mem_map.nr_map; i++) {
556 if (mem >= boot_mem_map.map[i].addr &&
557 mem < (boot_mem_map.map[i].addr +
558 boot_mem_map.map[i].size))
559 return;
561 add_memory_region(mem, size, type);
564 #ifdef CONFIG_KEXEC
565 static inline unsigned long long get_total_mem(void)
567 unsigned long long total;
569 total = max_pfn - min_low_pfn;
570 return total << PAGE_SHIFT;
573 static void __init mips_parse_crashkernel(void)
575 unsigned long long total_mem;
576 unsigned long long crash_size, crash_base;
577 int ret;
579 total_mem = get_total_mem();
580 ret = parse_crashkernel(boot_command_line, total_mem,
581 &crash_size, &crash_base);
582 if (ret != 0 || crash_size <= 0)
583 return;
585 crashk_res.start = crash_base;
586 crashk_res.end = crash_base + crash_size - 1;
589 static void __init request_crashkernel(struct resource *res)
591 int ret;
593 ret = request_resource(res, &crashk_res);
594 if (!ret)
595 pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
596 (unsigned long)((crashk_res.end -
597 crashk_res.start + 1) >> 20),
598 (unsigned long)(crashk_res.start >> 20));
600 #else /* !defined(CONFIG_KEXEC) */
601 static void __init mips_parse_crashkernel(void)
605 static void __init request_crashkernel(struct resource *res)
608 #endif /* !defined(CONFIG_KEXEC) */
610 static void __init arch_mem_init(char **cmdline_p)
612 extern void plat_mem_setup(void);
614 /* call board setup routine */
615 plat_mem_setup();
618 * Make sure all kernel memory is in the maps. The "UP" and
619 * "DOWN" are opposite for initdata since if it crosses over
620 * into another memory section you don't want that to be
621 * freed when the initdata is freed.
623 arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
624 PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
625 BOOT_MEM_RAM);
626 arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
627 PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
628 BOOT_MEM_INIT_RAM);
630 pr_info("Determined physical RAM map:\n");
631 print_memory_map();
633 #ifdef CONFIG_CMDLINE_BOOL
634 #ifdef CONFIG_CMDLINE_OVERRIDE
635 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
636 #else
637 if (builtin_cmdline[0]) {
638 strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
639 strlcat(arcs_cmdline, builtin_cmdline, COMMAND_LINE_SIZE);
641 strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
642 #endif
643 #else
644 strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
645 #endif
646 strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
648 *cmdline_p = command_line;
650 parse_early_param();
652 if (usermem) {
653 pr_info("User-defined physical RAM map:\n");
654 print_memory_map();
657 bootmem_init();
658 #ifdef CONFIG_PROC_VMCORE
659 if (setup_elfcorehdr && setup_elfcorehdr_size) {
660 printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
661 setup_elfcorehdr, setup_elfcorehdr_size);
662 reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size,
663 BOOTMEM_DEFAULT);
665 #endif
667 mips_parse_crashkernel();
668 #ifdef CONFIG_KEXEC
669 if (crashk_res.start != crashk_res.end)
670 reserve_bootmem(crashk_res.start,
671 crashk_res.end - crashk_res.start + 1,
672 BOOTMEM_DEFAULT);
673 #endif
674 device_tree_init();
675 sparse_init();
676 plat_swiotlb_setup();
677 paging_init();
680 static void __init resource_init(void)
682 int i;
684 if (UNCAC_BASE != IO_BASE)
685 return;
687 code_resource.start = __pa_symbol(&_text);
688 code_resource.end = __pa_symbol(&_etext) - 1;
689 data_resource.start = __pa_symbol(&_etext);
690 data_resource.end = __pa_symbol(&_edata) - 1;
692 for (i = 0; i < boot_mem_map.nr_map; i++) {
693 struct resource *res;
694 unsigned long start, end;
696 start = boot_mem_map.map[i].addr;
697 end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
698 if (start >= HIGHMEM_START)
699 continue;
700 if (end >= HIGHMEM_START)
701 end = HIGHMEM_START - 1;
703 res = alloc_bootmem(sizeof(struct resource));
704 switch (boot_mem_map.map[i].type) {
705 case BOOT_MEM_RAM:
706 case BOOT_MEM_INIT_RAM:
707 case BOOT_MEM_ROM_DATA:
708 res->name = "System RAM";
709 break;
710 case BOOT_MEM_RESERVED:
711 default:
712 res->name = "reserved";
715 res->start = start;
716 res->end = end;
718 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
719 request_resource(&iomem_resource, res);
722 * We don't know which RAM region contains kernel data,
723 * so we try it repeatedly and let the resource manager
724 * test it.
726 request_resource(res, &code_resource);
727 request_resource(res, &data_resource);
728 request_crashkernel(res);
732 void __init setup_arch(char **cmdline_p)
734 cpu_probe();
735 prom_init();
737 #ifdef CONFIG_EARLY_PRINTK
738 setup_early_printk();
739 #endif
740 cpu_report();
741 check_bugs_early();
743 #if defined(CONFIG_VT)
744 #if defined(CONFIG_VGA_CONSOLE)
745 conswitchp = &vga_con;
746 #elif defined(CONFIG_DUMMY_CONSOLE)
747 conswitchp = &dummy_con;
748 #endif
749 #endif
751 arch_mem_init(cmdline_p);
753 resource_init();
754 plat_smp_setup();
756 cpu_cache_init();
759 unsigned long kernelsp[NR_CPUS];
760 unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
762 #ifdef CONFIG_DEBUG_FS
763 struct dentry *mips_debugfs_dir;
764 static int __init debugfs_mips(void)
766 struct dentry *d;
768 d = debugfs_create_dir("mips", NULL);
769 if (!d)
770 return -ENOMEM;
771 mips_debugfs_dir = d;
772 return 0;
774 arch_initcall(debugfs_mips);
775 #endif