3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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)
10 * Derived from "arch/i386/mm/init.c"
11 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
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.
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>
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 #include <linux/vmalloc.h>
40 #include <asm/pgalloc.h>
43 #include <asm/mmu_context.h>
44 #include <asm/pgtable.h>
47 #include <asm/machdep.h>
48 #include <asm/btext.h>
50 #include <asm/sections.h>
51 #include <asm/sparsemem.h>
53 #include <asm/fixmap.h>
54 #include <asm/swiotlb.h>
59 #ifndef CPU_FTR_COHERENT_ICACHE
60 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
61 #define CPU_FTR_NOEXECUTE 0
64 unsigned long long memory_limit;
68 EXPORT_SYMBOL(kmap_pte);
70 EXPORT_SYMBOL(kmap_prot);
71 #define TOP_ZONE ZONE_HIGHMEM
73 static inline pte_t *virt_to_kpte(unsigned long vaddr)
75 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
76 vaddr), vaddr), vaddr);
79 #define TOP_ZONE ZONE_NORMAL
82 int page_is_ram(unsigned long pfn)
84 #ifndef CONFIG_PPC64 /* XXX for now */
87 unsigned long paddr = (pfn << PAGE_SHIFT);
88 struct memblock_region *reg;
90 for_each_memblock(memory, reg)
91 if (paddr >= reg->base && paddr < (reg->base + reg->size))
97 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
98 unsigned long size, pgprot_t vma_prot)
100 if (ppc_md.phys_mem_access_prot)
101 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
103 if (!page_is_ram(pfn))
104 vma_prot = pgprot_noncached(vma_prot);
108 EXPORT_SYMBOL(phys_mem_access_prot);
110 #ifdef CONFIG_MEMORY_HOTPLUG
113 int memory_add_physaddr_to_nid(u64 start)
115 return hot_add_scn_to_nid(start);
119 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
121 struct pglist_data *pgdata;
123 unsigned long start_pfn = start >> PAGE_SHIFT;
124 unsigned long nr_pages = size >> PAGE_SHIFT;
127 pgdata = NODE_DATA(nid);
129 start = (unsigned long)__va(start);
130 rc = create_section_mapping(start, start + size);
133 "Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
134 start, start + size, rc);
138 /* this should work for most non-highmem platforms */
139 zone = pgdata->node_zones +
140 zone_for_memory(nid, start, size, 0, for_device);
142 return __add_pages(nid, zone, start_pfn, nr_pages);
145 #ifdef CONFIG_MEMORY_HOTREMOVE
146 int arch_remove_memory(u64 start, u64 size)
148 unsigned long start_pfn = start >> PAGE_SHIFT;
149 unsigned long nr_pages = size >> PAGE_SHIFT;
153 zone = page_zone(pfn_to_page(start_pfn));
154 ret = __remove_pages(zone, start_pfn, nr_pages);
158 /* Remove htab bolted mappings for this section of memory */
159 start = (unsigned long)__va(start);
160 ret = remove_section_mapping(start, start + size);
162 /* Ensure all vmalloc mappings are flushed in case they also
163 * hit that section of memory
170 #endif /* CONFIG_MEMORY_HOTPLUG */
173 * walk_memory_resource() needs to make sure there is no holes in a given
174 * memory range. PPC64 does not maintain the memory layout in /proc/iomem.
175 * Instead it maintains it in memblock.memory structures. Walk through the
176 * memory regions, find holes and callback for contiguous regions.
179 walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
180 void *arg, int (*func)(unsigned long, unsigned long, void *))
182 struct memblock_region *reg;
183 unsigned long end_pfn = start_pfn + nr_pages;
184 unsigned long tstart, tend;
187 for_each_memblock(memory, reg) {
188 tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
189 tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
192 ret = (*func)(tstart, tend - tstart, arg);
198 EXPORT_SYMBOL_GPL(walk_system_ram_range);
200 #ifndef CONFIG_NEED_MULTIPLE_NODES
201 void __init initmem_init(void)
203 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
204 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
205 #ifdef CONFIG_HIGHMEM
206 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
209 /* Place all memblock_regions in the same node and merge contiguous
212 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
214 /* XXX need to clip this if using highmem? */
215 sparse_memory_present_with_active_regions(0);
219 /* mark pages that don't exist as nosave */
220 static int __init mark_nonram_nosave(void)
222 struct memblock_region *reg, *prev = NULL;
224 for_each_memblock(memory, reg) {
226 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
227 register_nosave_region(memblock_region_memory_end_pfn(prev),
228 memblock_region_memory_base_pfn(reg));
233 #else /* CONFIG_NEED_MULTIPLE_NODES */
234 static int __init mark_nonram_nosave(void)
240 static bool zone_limits_final;
242 static unsigned long max_zone_pfns[MAX_NR_ZONES] = {
243 [0 ... MAX_NR_ZONES - 1] = ~0UL
247 * Restrict the specified zone and all more restrictive zones
248 * to be below the specified pfn. May not be called after
251 void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit)
255 if (WARN_ON(zone_limits_final))
258 for (i = zone; i >= 0; i--) {
259 if (max_zone_pfns[i] > pfn_limit)
260 max_zone_pfns[i] = pfn_limit;
265 * Find the least restrictive zone that is entirely below the
266 * specified pfn limit. Returns < 0 if no suitable zone is found.
268 * pfn_limit must be u64 because it can exceed 32 bits even on 32-bit
269 * systems -- the DMA limit can be higher than any possible real pfn.
271 int dma_pfn_limit_to_zone(u64 pfn_limit)
275 for (i = TOP_ZONE; i >= 0; i--) {
276 if (max_zone_pfns[i] <= pfn_limit)
284 * paging_init() sets up the page tables - in fact we've already done this.
286 void __init paging_init(void)
288 unsigned long long total_ram = memblock_phys_mem_size();
289 phys_addr_t top_of_ram = memblock_end_of_DRAM();
292 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
293 unsigned long end = __fix_to_virt(FIX_HOLE);
295 for (; v < end; v += PAGE_SIZE)
296 map_page(v, 0, 0); /* XXX gross */
299 #ifdef CONFIG_HIGHMEM
300 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
301 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
303 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
304 kmap_prot = PAGE_KERNEL;
305 #endif /* CONFIG_HIGHMEM */
307 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
308 (unsigned long long)top_of_ram, total_ram);
309 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
310 (long int)((top_of_ram - total_ram) >> 20));
312 #ifdef CONFIG_HIGHMEM
313 limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT);
315 limit_zone_pfn(TOP_ZONE, top_of_ram >> PAGE_SHIFT);
316 zone_limits_final = true;
317 free_area_init_nodes(max_zone_pfns);
319 mark_nonram_nosave();
322 void __init mem_init(void)
325 * book3s is limited to 16 page sizes due to encoding this in
326 * a 4-bit field for slices.
328 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
330 #ifdef CONFIG_SWIOTLB
334 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
335 set_max_mapnr(max_pfn);
338 #ifdef CONFIG_HIGHMEM
340 unsigned long pfn, highmem_mapnr;
342 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
343 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
344 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
345 struct page *page = pfn_to_page(pfn);
346 if (!memblock_is_reserved(paddr))
347 free_highmem_page(page);
350 #endif /* CONFIG_HIGHMEM */
352 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
354 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
355 * functions.... do it here for the non-smp case.
357 per_cpu(next_tlbcam_idx, smp_processor_id()) =
358 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
361 mem_init_print_info(NULL);
363 pr_info("Kernel virtual memory layout:\n");
364 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
365 #ifdef CONFIG_HIGHMEM
366 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
367 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
368 #endif /* CONFIG_HIGHMEM */
369 #ifdef CONFIG_NOT_COHERENT_CACHE
370 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
371 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
372 #endif /* CONFIG_NOT_COHERENT_CACHE */
373 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
374 ioremap_bot, IOREMAP_TOP);
375 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
376 VMALLOC_START, VMALLOC_END);
377 #endif /* CONFIG_PPC32 */
380 void free_initmem(void)
382 ppc_md.progress = ppc_printk_progress;
383 free_initmem_default(POISON_FREE_INITMEM);
386 #ifdef CONFIG_BLK_DEV_INITRD
387 void __init free_initrd_mem(unsigned long start, unsigned long end)
389 free_reserved_area((void *)start, (void *)end, -1, "initrd");
394 * This is called when a page has been modified by the kernel.
395 * It just marks the page as not i-cache clean. We do the i-cache
396 * flush later when the page is given to a user process, if necessary.
398 void flush_dcache_page(struct page *page)
400 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
402 /* avoid an atomic op if possible */
403 if (test_bit(PG_arch_1, &page->flags))
404 clear_bit(PG_arch_1, &page->flags);
406 EXPORT_SYMBOL(flush_dcache_page);
408 void flush_dcache_icache_page(struct page *page)
410 #ifdef CONFIG_HUGETLB_PAGE
411 if (PageCompound(page)) {
412 flush_dcache_icache_hugepage(page);
416 #if defined(CONFIG_8xx) || defined(CONFIG_PPC64)
417 /* On 8xx there is no need to kmap since highmem is not supported */
418 __flush_dcache_icache(page_address(page));
420 if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
421 void *start = kmap_atomic(page);
422 __flush_dcache_icache(start);
423 kunmap_atomic(start);
425 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
429 EXPORT_SYMBOL(flush_dcache_icache_page);
431 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
436 * We shouldn't have to do this, but some versions of glibc
437 * require it (ld.so assumes zero filled pages are icache clean)
440 flush_dcache_page(pg);
442 EXPORT_SYMBOL(clear_user_page);
444 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
447 copy_page(vto, vfrom);
450 * We should be able to use the following optimisation, however
451 * there are two problems.
452 * Firstly a bug in some versions of binutils meant PLT sections
453 * were not marked executable.
454 * Secondly the first word in the GOT section is blrl, used
455 * to establish the GOT address. Until recently the GOT was
456 * not marked executable.
460 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
464 flush_dcache_page(pg);
467 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
468 unsigned long addr, int len)
472 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
473 flush_icache_range(maddr, maddr + len);
476 EXPORT_SYMBOL(flush_icache_user_range);
479 * This is called at the end of handling a user page fault, when the
480 * fault has been handled by updating a PTE in the linux page tables.
481 * We use it to preload an HPTE into the hash table corresponding to
482 * the updated linux PTE.
484 * This must always be called with the pte lock held.
486 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
489 #ifdef CONFIG_PPC_STD_MMU
491 * We don't need to worry about _PAGE_PRESENT here because we are
492 * called with either mm->page_table_lock held or ptl lock held
494 unsigned long access, trap;
499 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
500 if (!pte_young(*ptep) || address >= TASK_SIZE)
503 /* We try to figure out if we are coming from an instruction
504 * access fault and pass that down to __hash_page so we avoid
505 * double-faulting on execution of fresh text. We have to test
506 * for regs NULL since init will get here first thing at boot
508 * We also avoid filling the hash if not coming from a fault
511 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL;
523 hash_preload(vma->vm_mm, address, access, trap);
524 #endif /* CONFIG_PPC_STD_MMU */
525 #if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
526 && defined(CONFIG_HUGETLB_PAGE)
527 if (is_vm_hugetlb_page(vma))
528 book3e_hugetlb_preload(vma, address, *ptep);
533 * System memory should not be in /proc/iomem but various tools expect it
536 static int __init add_system_ram_resources(void)
538 struct memblock_region *reg;
540 for_each_memblock(memory, reg) {
541 struct resource *res;
542 unsigned long base = reg->base;
543 unsigned long size = reg->size;
545 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
549 res->name = "System RAM";
551 res->end = base + size - 1;
552 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
553 WARN_ON(request_resource(&iomem_resource, res) < 0);
559 subsys_initcall(add_system_ram_resources);
561 #ifdef CONFIG_STRICT_DEVMEM
563 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
564 * is valid. The argument is a physical page number.
566 * Access has to be given to non-kernel-ram areas as well, these contain the
567 * PCI mmio resources as well as potential bios/acpi data regions.
569 int devmem_is_allowed(unsigned long pfn)
571 if (page_is_rtas_user_buf(pfn))
573 if (iomem_is_exclusive(PFN_PHYS(pfn)))
575 if (!page_is_ram(pfn))
579 #endif /* CONFIG_STRICT_DEVMEM */