1 /*
2 * PowerPC version
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
6 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
7 * Copyright (C) 1996 Paul Mackerras
8 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
9 *
10 * Derived from "arch/i386/mm/init.c"
11 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 *
18 */
19
20 #include <linux/export.h>
21 #include <linux/sched.h>
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/gfp.h>
26 #include <linux/types.h>
27 #include <linux/mm.h>
28 #include <linux/stddef.h>
29 #include <linux/init.h>
30 #include <linux/bootmem.h>
31 #include <linux/highmem.h>
32 #include <linux/initrd.h>
33 #include <linux/pagemap.h>
34 #include <linux/suspend.h>
35 #include <linux/memblock.h>
36 #include <linux/hugetlb.h>
37 #include <linux/slab.h>
38
39 #include <asm/pgalloc.h>
40 #include <asm/prom.h>
41 #include <asm/io.h>
42 #include <asm/mmu_context.h>
43 #include <asm/pgtable.h>
44 #include <asm/mmu.h>
45 #include <asm/smp.h>
46 #include <asm/machdep.h>
47 #include <asm/btext.h>
48 #include <asm/tlb.h>
49 #include <asm/sections.h>
50 #include <asm/sparsemem.h>
51 #include <asm/vdso.h>
52 #include <asm/fixmap.h>
53 #include <asm/swiotlb.h>
54 #include <asm/rtas.h>
55
56 #include "mmu_decl.h"
57
58 #ifndef CPU_FTR_COHERENT_ICACHE
59 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
60 #define CPU_FTR_NOEXECUTE 0
61 #endif
62
63 int init_bootmem_done;
64 int mem_init_done;
65 phys_addr_t memory_limit;
66
67 #ifdef CONFIG_HIGHMEM
68 pte_t *kmap_pte;
69 pgprot_t kmap_prot;
70
71 EXPORT_SYMBOL(kmap_prot);
72 EXPORT_SYMBOL(kmap_pte);
73
virt_to_kpte(unsigned long vaddr)74 static inline pte_t *virt_to_kpte(unsigned long vaddr)
75 {
76 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
77 vaddr), vaddr), vaddr);
78 }
79 #endif
80
page_is_ram(unsigned long pfn)81 int page_is_ram(unsigned long pfn)
82 {
83 #ifndef CONFIG_PPC64 /* XXX for now */
84 return pfn < max_pfn;
85 #else
86 unsigned long paddr = (pfn << PAGE_SHIFT);
87 struct memblock_region *reg;
88
89 for_each_memblock(memory, reg)
90 if (paddr >= reg->base && paddr < (reg->base + reg->size))
91 return 1;
92 return 0;
93 #endif
94 }
95
phys_mem_access_prot(struct file * file,unsigned long pfn,unsigned long size,pgprot_t vma_prot)96 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
97 unsigned long size, pgprot_t vma_prot)
98 {
99 if (ppc_md.phys_mem_access_prot)
100 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
101
102 if (!page_is_ram(pfn))
103 vma_prot = pgprot_noncached(vma_prot);
104
105 return vma_prot;
106 }
107 EXPORT_SYMBOL(phys_mem_access_prot);
108
109 #ifdef CONFIG_MEMORY_HOTPLUG
110
111 #ifdef CONFIG_NUMA
memory_add_physaddr_to_nid(u64 start)112 int memory_add_physaddr_to_nid(u64 start)
113 {
114 return hot_add_scn_to_nid(start);
115 }
116 #endif
117
arch_add_memory(int nid,u64 start,u64 size)118 int arch_add_memory(int nid, u64 start, u64 size)
119 {
120 struct pglist_data *pgdata;
121 struct zone *zone;
122 unsigned long start_pfn = start >> PAGE_SHIFT;
123 unsigned long nr_pages = size >> PAGE_SHIFT;
124
125 pgdata = NODE_DATA(nid);
126
127 start = (unsigned long)__va(start);
128 if (create_section_mapping(start, start + size))
129 return -EINVAL;
130
131 /* this should work for most non-highmem platforms */
132 zone = pgdata->node_zones;
133
134 return __add_pages(nid, zone, start_pfn, nr_pages);
135 }
136 #endif /* CONFIG_MEMORY_HOTPLUG */
137
138 /*
139 * walk_memory_resource() needs to make sure there is no holes in a given
140 * memory range. PPC64 does not maintain the memory layout in /proc/iomem.
141 * Instead it maintains it in memblock.memory structures. Walk through the
142 * memory regions, find holes and callback for contiguous regions.
143 */
144 int
walk_system_ram_range(unsigned long start_pfn,unsigned long nr_pages,void * arg,int (* func)(unsigned long,unsigned long,void *))145 walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
146 void *arg, int (*func)(unsigned long, unsigned long, void *))
147 {
148 struct memblock_region *reg;
149 unsigned long end_pfn = start_pfn + nr_pages;
150 unsigned long tstart, tend;
151 int ret = -1;
152
153 for_each_memblock(memory, reg) {
154 tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
155 tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
156 if (tstart >= tend)
157 continue;
158 ret = (*func)(tstart, tend - tstart, arg);
159 if (ret)
160 break;
161 }
162 return ret;
163 }
164 EXPORT_SYMBOL_GPL(walk_system_ram_range);
165
166 /*
167 * Initialize the bootmem system and give it all the memory we
168 * have available. If we are using highmem, we only put the
169 * lowmem into the bootmem system.
170 */
171 #ifndef CONFIG_NEED_MULTIPLE_NODES
do_init_bootmem(void)172 void __init do_init_bootmem(void)
173 {
174 unsigned long start, bootmap_pages;
175 unsigned long total_pages;
176 struct memblock_region *reg;
177 int boot_mapsize;
178
179 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
180 total_pages = (memblock_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
181 #ifdef CONFIG_HIGHMEM
182 total_pages = total_lowmem >> PAGE_SHIFT;
183 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
184 #endif
185
186 /*
187 * Find an area to use for the bootmem bitmap. Calculate the size of
188 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
189 * Add 1 additional page in case the address isn't page-aligned.
190 */
191 bootmap_pages = bootmem_bootmap_pages(total_pages);
192
193 start = memblock_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE);
194
195 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
196 boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn);
197
198 /* Add active regions with valid PFNs */
199 for_each_memblock(memory, reg) {
200 unsigned long start_pfn, end_pfn;
201 start_pfn = memblock_region_memory_base_pfn(reg);
202 end_pfn = memblock_region_memory_end_pfn(reg);
203 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
204 }
205
206 /* Add all physical memory to the bootmem map, mark each area
207 * present.
208 */
209 #ifdef CONFIG_HIGHMEM
210 free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);
211
212 /* reserve the sections we're already using */
213 for_each_memblock(reserved, reg) {
214 unsigned long top = reg->base + reg->size - 1;
215 if (top < lowmem_end_addr)
216 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
217 else if (reg->base < lowmem_end_addr) {
218 unsigned long trunc_size = lowmem_end_addr - reg->base;
219 reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
220 }
221 }
222 #else
223 free_bootmem_with_active_regions(0, max_pfn);
224
225 /* reserve the sections we're already using */
226 for_each_memblock(reserved, reg)
227 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
228 #endif
229 /* XXX need to clip this if using highmem? */
230 sparse_memory_present_with_active_regions(0);
231
232 init_bootmem_done = 1;
233 }
234
235 /* mark pages that don't exist as nosave */
mark_nonram_nosave(void)236 static int __init mark_nonram_nosave(void)
237 {
238 struct memblock_region *reg, *prev = NULL;
239
240 for_each_memblock(memory, reg) {
241 if (prev &&
242 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
243 register_nosave_region(memblock_region_memory_end_pfn(prev),
244 memblock_region_memory_base_pfn(reg));
245 prev = reg;
246 }
247 return 0;
248 }
249
250 /*
251 * paging_init() sets up the page tables - in fact we've already done this.
252 */
paging_init(void)253 void __init paging_init(void)
254 {
255 unsigned long long total_ram = memblock_phys_mem_size();
256 phys_addr_t top_of_ram = memblock_end_of_DRAM();
257 unsigned long max_zone_pfns[MAX_NR_ZONES];
258
259 #ifdef CONFIG_PPC32
260 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
261 unsigned long end = __fix_to_virt(FIX_HOLE);
262
263 for (; v < end; v += PAGE_SIZE)
264 map_page(v, 0, 0); /* XXX gross */
265 #endif
266
267 #ifdef CONFIG_HIGHMEM
268 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
269 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
270
271 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
272 kmap_prot = PAGE_KERNEL;
273 #endif /* CONFIG_HIGHMEM */
274
275 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
276 (unsigned long long)top_of_ram, total_ram);
277 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
278 (long int)((top_of_ram - total_ram) >> 20));
279 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
280 #ifdef CONFIG_HIGHMEM
281 max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
282 max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
283 #else
284 max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
285 #endif
286 free_area_init_nodes(max_zone_pfns);
287
288 mark_nonram_nosave();
289 }
290 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */
291
mem_init(void)292 void __init mem_init(void)
293 {
294 #ifdef CONFIG_NEED_MULTIPLE_NODES
295 int nid;
296 #endif
297 pg_data_t *pgdat;
298 unsigned long i;
299 struct page *page;
300 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
301
302 #ifdef CONFIG_SWIOTLB
303 if (ppc_swiotlb_enable)
304 swiotlb_init(1);
305 #endif
306
307 num_physpages = memblock_phys_mem_size() >> PAGE_SHIFT;
308 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
309
310 #ifdef CONFIG_NEED_MULTIPLE_NODES
311 for_each_online_node(nid) {
312 if (NODE_DATA(nid)->node_spanned_pages != 0) {
313 printk("freeing bootmem node %d\n", nid);
314 totalram_pages +=
315 free_all_bootmem_node(NODE_DATA(nid));
316 }
317 }
318 #else
319 max_mapnr = max_pfn;
320 totalram_pages += free_all_bootmem();
321 #endif
322 for_each_online_pgdat(pgdat) {
323 for (i = 0; i < pgdat->node_spanned_pages; i++) {
324 if (!pfn_valid(pgdat->node_start_pfn + i))
325 continue;
326 page = pgdat_page_nr(pgdat, i);
327 if (PageReserved(page))
328 reservedpages++;
329 }
330 }
331
332 codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
333 datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
334 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
335 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
336
337 #ifdef CONFIG_HIGHMEM
338 {
339 unsigned long pfn, highmem_mapnr;
340
341 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
342 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
343 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
344 struct page *page = pfn_to_page(pfn);
345 if (memblock_is_reserved(paddr))
346 continue;
347 ClearPageReserved(page);
348 init_page_count(page);
349 __free_page(page);
350 totalhigh_pages++;
351 reservedpages--;
352 }
353 totalram_pages += totalhigh_pages;
354 printk(KERN_DEBUG "High memory: %luk\n",
355 totalhigh_pages << (PAGE_SHIFT-10));
356 }
357 #endif /* CONFIG_HIGHMEM */
358
359 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
360 /*
361 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
362 * functions.... do it here for the non-smp case.
363 */
364 per_cpu(next_tlbcam_idx, smp_processor_id()) =
365 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
366 #endif
367
368 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
369 "%luk reserved, %luk data, %luk bss, %luk init)\n",
370 nr_free_pages() << (PAGE_SHIFT-10),
371 num_physpages << (PAGE_SHIFT-10),
372 codesize >> 10,
373 reservedpages << (PAGE_SHIFT-10),
374 datasize >> 10,
375 bsssize >> 10,
376 initsize >> 10);
377
378 #ifdef CONFIG_PPC32
379 pr_info("Kernel virtual memory layout:\n");
380 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
381 #ifdef CONFIG_HIGHMEM
382 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
383 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
384 #endif /* CONFIG_HIGHMEM */
385 #ifdef CONFIG_NOT_COHERENT_CACHE
386 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
387 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
388 #endif /* CONFIG_NOT_COHERENT_CACHE */
389 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
390 ioremap_bot, IOREMAP_TOP);
391 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
392 VMALLOC_START, VMALLOC_END);
393 #endif /* CONFIG_PPC32 */
394
395 mem_init_done = 1;
396 }
397
free_initmem(void)398 void free_initmem(void)
399 {
400 unsigned long addr;
401
402 ppc_md.progress = ppc_printk_progress;
403
404 addr = (unsigned long)__init_begin;
405 for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
406 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
407 ClearPageReserved(virt_to_page(addr));
408 init_page_count(virt_to_page(addr));
409 free_page(addr);
410 totalram_pages++;
411 }
412 pr_info("Freeing unused kernel memory: %luk freed\n",
413 ((unsigned long)__init_end -
414 (unsigned long)__init_begin) >> 10);
415 }
416
417 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)418 void __init free_initrd_mem(unsigned long start, unsigned long end)
419 {
420 if (start >= end)
421 return;
422
423 start = _ALIGN_DOWN(start, PAGE_SIZE);
424 end = _ALIGN_UP(end, PAGE_SIZE);
425 pr_info("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
426
427 for (; start < end; start += PAGE_SIZE) {
428 ClearPageReserved(virt_to_page(start));
429 init_page_count(virt_to_page(start));
430 free_page(start);
431 totalram_pages++;
432 }
433 }
434 #endif
435
436 /*
437 * This is called when a page has been modified by the kernel.
438 * It just marks the page as not i-cache clean. We do the i-cache
439 * flush later when the page is given to a user process, if necessary.
440 */
flush_dcache_page(struct page * page)441 void flush_dcache_page(struct page *page)
442 {
443 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
444 return;
445 /* avoid an atomic op if possible */
446 if (test_bit(PG_arch_1, &page->flags))
447 clear_bit(PG_arch_1, &page->flags);
448 }
449 EXPORT_SYMBOL(flush_dcache_page);
450
flush_dcache_icache_page(struct page * page)451 void flush_dcache_icache_page(struct page *page)
452 {
453 #ifdef CONFIG_HUGETLB_PAGE
454 if (PageCompound(page)) {
455 flush_dcache_icache_hugepage(page);
456 return;
457 }
458 #endif
459 #ifdef CONFIG_BOOKE
460 {
461 void *start = kmap_atomic(page);
462 __flush_dcache_icache(start);
463 kunmap_atomic(start);
464 }
465 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64)
466 /* On 8xx there is no need to kmap since highmem is not supported */
467 __flush_dcache_icache(page_address(page));
468 #else
469 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
470 #endif
471 }
472
clear_user_page(void * page,unsigned long vaddr,struct page * pg)473 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
474 {
475 clear_page(page);
476
477 /*
478 * We shouldn't have to do this, but some versions of glibc
479 * require it (ld.so assumes zero filled pages are icache clean)
480 * - Anton
481 */
482 flush_dcache_page(pg);
483 }
484 EXPORT_SYMBOL(clear_user_page);
485
copy_user_page(void * vto,void * vfrom,unsigned long vaddr,struct page * pg)486 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
487 struct page *pg)
488 {
489 copy_page(vto, vfrom);
490
491 /*
492 * We should be able to use the following optimisation, however
493 * there are two problems.
494 * Firstly a bug in some versions of binutils meant PLT sections
495 * were not marked executable.
496 * Secondly the first word in the GOT section is blrl, used
497 * to establish the GOT address. Until recently the GOT was
498 * not marked executable.
499 * - Anton
500 */
501 #if 0
502 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
503 return;
504 #endif
505
506 flush_dcache_page(pg);
507 }
508
flush_icache_user_range(struct vm_area_struct * vma,struct page * page,unsigned long addr,int len)509 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
510 unsigned long addr, int len)
511 {
512 unsigned long maddr;
513
514 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
515 flush_icache_range(maddr, maddr + len);
516 kunmap(page);
517 }
518 EXPORT_SYMBOL(flush_icache_user_range);
519
520 /*
521 * This is called at the end of handling a user page fault, when the
522 * fault has been handled by updating a PTE in the linux page tables.
523 * We use it to preload an HPTE into the hash table corresponding to
524 * the updated linux PTE.
525 *
526 * This must always be called with the pte lock held.
527 */
update_mmu_cache(struct vm_area_struct * vma,unsigned long address,pte_t * ptep)528 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
529 pte_t *ptep)
530 {
531 #ifdef CONFIG_PPC_STD_MMU
532 unsigned long access = 0, trap;
533
534 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
535 if (!pte_young(*ptep) || address >= TASK_SIZE)
536 return;
537
538 /* We try to figure out if we are coming from an instruction
539 * access fault and pass that down to __hash_page so we avoid
540 * double-faulting on execution of fresh text. We have to test
541 * for regs NULL since init will get here first thing at boot
542 *
543 * We also avoid filling the hash if not coming from a fault
544 */
545 if (current->thread.regs == NULL)
546 return;
547 trap = TRAP(current->thread.regs);
548 if (trap == 0x400)
549 access |= _PAGE_EXEC;
550 else if (trap != 0x300)
551 return;
552 hash_preload(vma->vm_mm, address, access, trap);
553 #endif /* CONFIG_PPC_STD_MMU */
554 #if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
555 && defined(CONFIG_HUGETLB_PAGE)
556 if (is_vm_hugetlb_page(vma))
557 book3e_hugetlb_preload(vma, address, *ptep);
558 #endif
559 }
560
561 /*
562 * System memory should not be in /proc/iomem but various tools expect it
563 * (eg kdump).
564 */
add_system_ram_resources(void)565 static int add_system_ram_resources(void)
566 {
567 struct memblock_region *reg;
568
569 for_each_memblock(memory, reg) {
570 struct resource *res;
571 unsigned long base = reg->base;
572 unsigned long size = reg->size;
573
574 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
575 WARN_ON(!res);
576
577 if (res) {
578 res->name = "System RAM";
579 res->start = base;
580 res->end = base + size - 1;
581 res->flags = IORESOURCE_MEM;
582 WARN_ON(request_resource(&iomem_resource, res) < 0);
583 }
584 }
585
586 return 0;
587 }
588 subsys_initcall(add_system_ram_resources);
589
590 #ifdef CONFIG_STRICT_DEVMEM
591 /*
592 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
593 * is valid. The argument is a physical page number.
594 *
595 * Access has to be given to non-kernel-ram areas as well, these contain the
596 * PCI mmio resources as well as potential bios/acpi data regions.
597 */
devmem_is_allowed(unsigned long pfn)598 int devmem_is_allowed(unsigned long pfn)
599 {
600 if (iomem_is_exclusive(pfn << PAGE_SHIFT))
601 return 0;
602 if (!page_is_ram(pfn))
603 return 1;
604 if (page_is_rtas_user_buf(pfn))
605 return 1;
606 return 0;
607 }
608 #endif /* CONFIG_STRICT_DEVMEM */
609