/* * This file contains the routines setting up the linux page tables. * -- paulus * * Derived from arch/ppc/mm/init.c: * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) * and Cort Dougan (PReP) (cort@cs.nmt.edu) * Copyright (C) 1996 Paul Mackerras * * Derived from "arch/i386/mm/init.c" * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mmu_decl.h" unsigned long ioremap_base; unsigned long ioremap_bot; EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */ #ifdef CONFIG_6xx #define HAVE_BATS 1 #endif #if defined(CONFIG_FSL_BOOKE) #define HAVE_TLBCAM 1 #endif extern char etext[], _stext[]; #ifdef HAVE_BATS extern phys_addr_t v_mapped_by_bats(unsigned long va); extern unsigned long p_mapped_by_bats(phys_addr_t pa); #else /* !HAVE_BATS */ #define v_mapped_by_bats(x) (0UL) #define p_mapped_by_bats(x) (0UL) #endif /* HAVE_BATS */ #ifdef HAVE_TLBCAM extern phys_addr_t v_mapped_by_tlbcam(unsigned long va); extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa); #else /* !HAVE_TLBCAM */ #define v_mapped_by_tlbcam(x) (0UL) #define p_mapped_by_tlbcam(x) (0UL) #endif /* HAVE_TLBCAM */ #define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT) #ifndef CONFIG_PPC_4K_PAGES static struct kmem_cache *pgtable_cache; void pgtable_cache_init(void) { pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER, 1 << PGDIR_ORDER, 0, NULL); if (pgtable_cache == NULL) panic("Couldn't allocate pgtable caches"); } #endif pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *ret; /* pgdir take page or two with 4K pages and a page fraction otherwise */ #ifndef CONFIG_PPC_4K_PAGES ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO); #else ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER - PAGE_SHIFT); #endif return ret; } void pgd_free(struct mm_struct *mm, pgd_t *pgd) { #ifndef CONFIG_PPC_4K_PAGES kmem_cache_free(pgtable_cache, (void *)pgd); #else free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT); #endif } __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { pte_t *pte; extern int mem_init_done; if (mem_init_done) { pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO); } else { pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE)); if (pte) clear_page(pte); } return pte; } pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address) { struct page *ptepage; gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO; ptepage = alloc_pages(flags, 0); if (!ptepage) return NULL; if (!pgtable_page_ctor(ptepage)) { __free_page(ptepage); return NULL; } return ptepage; } void __iomem * ioremap(phys_addr_t addr, unsigned long size) { return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED, __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap); void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size) { return __ioremap_caller(addr, size, _PAGE_NO_CACHE, __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap_wc); void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags) { /* writeable implies dirty for kernel addresses */ if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO) flags |= _PAGE_DIRTY | _PAGE_HWWRITE; /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */ flags &= ~(_PAGE_USER | _PAGE_EXEC); #ifdef _PAGE_BAP_SR /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format * which means that we just cleared supervisor access... oops ;-) This * restores it */ flags |= _PAGE_BAP_SR; #endif return __ioremap_caller(addr, size, flags, __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap_prot); void __iomem * __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags) { return __ioremap_caller(addr, size, flags, __builtin_return_address(0)); } void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags, void *caller) { unsigned long v, i; phys_addr_t p; int err; /* Make sure we have the base flags */ if ((flags & _PAGE_PRESENT) == 0) flags |= PAGE_KERNEL; /* Non-cacheable page cannot be coherent */ if (flags & _PAGE_NO_CACHE) flags &= ~_PAGE_COHERENT; /* * Choose an address to map it to. * Once the vmalloc system is running, we use it. * Before then, we use space going down from ioremap_base * (ioremap_bot records where we're up to). */ p = addr & PAGE_MASK; size = PAGE_ALIGN(addr + size) - p; /* * If the address lies within the first 16 MB, assume it's in ISA * memory space */ if (p < 16*1024*1024) p += _ISA_MEM_BASE; #ifndef CONFIG_CRASH_DUMP /* * Don't allow anybody to remap normal RAM that we're using. * mem_init() sets high_memory so only do the check after that. */ if (mem_init_done && (p < virt_to_phys(high_memory)) && !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) { printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n", (unsigned long long)p, __builtin_return_address(0)); return NULL; } #endif if (size == 0) return NULL; /* * Is it already mapped? Perhaps overlapped by a previous * BAT mapping. If the whole area is mapped then we're done, * otherwise remap it since we want to keep the virt addrs for * each request contiguous. * * We make the assumption here that if the bottom and top * of the range we want are mapped then it's mapped to the * same virt address (and this is contiguous). * -- Cort */ if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ ) goto out; if ((v = p_mapped_by_tlbcam(p))) goto out; if (mem_init_done) { struct vm_struct *area; area = get_vm_area_caller(size, VM_IOREMAP, caller); if (area == 0) return NULL; area->phys_addr = p; v = (unsigned long) area->addr; } else { v = (ioremap_bot -= size); } /* * Should check if it is a candidate for a BAT mapping */ err = 0; for (i = 0; i < size && err == 0; i += PAGE_SIZE) err = map_page(v+i, p+i, flags); if (err) { if (mem_init_done) vunmap((void *)v); return NULL; } out: return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK)); } EXPORT_SYMBOL(__ioremap); void iounmap(volatile void __iomem *addr) { /* * If mapped by BATs then there is nothing to do. * Calling vfree() generates a benign warning. */ if (v_mapped_by_bats((unsigned long)addr)) return; if (addr > high_memory && (unsigned long) addr < ioremap_bot) vunmap((void *) (PAGE_MASK & (unsigned long)addr)); } EXPORT_SYMBOL(iounmap); int map_page(unsigned long va, phys_addr_t pa, int flags) { pmd_t *pd; pte_t *pg; int err = -ENOMEM; /* Use upper 10 bits of VA to index the first level map */ pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va); /* Use middle 10 bits of VA to index the second-level map */ pg = pte_alloc_kernel(pd, va); if (pg != 0) { err = 0; /* The PTE should never be already set nor present in the * hash table */ BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) && flags); set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, __pgprot(flags))); } smp_wmb(); return err; } /* * Map in a chunk of physical memory starting at start. */ void __init __mapin_ram_chunk(unsigned long offset, unsigned long top) { unsigned long v, s, f; phys_addr_t p; int ktext; s = offset; v = PAGE_OFFSET + s; p = memstart_addr + s; for (; s < top; s += PAGE_SIZE) { ktext = ((char *) v >= _stext && (char *) v < etext); f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL; map_page(v, p, f); #ifdef CONFIG_PPC_STD_MMU_32 if (ktext) hash_preload(&init_mm, v, 0, 0x300); #endif v += PAGE_SIZE; p += PAGE_SIZE; } } void __init mapin_ram(void) { unsigned long s, top; #ifndef CONFIG_WII top = total_lowmem; s = mmu_mapin_ram(top); __mapin_ram_chunk(s, top); #else if (!wii_hole_size) { s = mmu_mapin_ram(total_lowmem); __mapin_ram_chunk(s, total_lowmem); } else { top = wii_hole_start; s = mmu_mapin_ram(top); __mapin_ram_chunk(s, top); top = memblock_end_of_DRAM(); s = wii_mmu_mapin_mem2(top); __mapin_ram_chunk(s, top); } #endif } /* Scan the real Linux page tables and return a PTE pointer for * a virtual address in a context. * Returns true (1) if PTE was found, zero otherwise. The pointer to * the PTE pointer is unmodified if PTE is not found. */ int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp) { pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; int retval = 0; pgd = pgd_offset(mm, addr & PAGE_MASK); if (pgd) { pud = pud_offset(pgd, addr & PAGE_MASK); if (pud && pud_present(*pud)) { pmd = pmd_offset(pud, addr & PAGE_MASK); if (pmd_present(*pmd)) { pte = pte_offset_map(pmd, addr & PAGE_MASK); if (pte) { retval = 1; *ptep = pte; if (pmdp) *pmdp = pmd; /* XXX caller needs to do pte_unmap, yuck */ } } } } return(retval); } #ifdef CONFIG_DEBUG_PAGEALLOC static int __change_page_attr(struct page *page, pgprot_t prot) { pte_t *kpte; pmd_t *kpmd; unsigned long address; BUG_ON(PageHighMem(page)); address = (unsigned long)page_address(page); if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address)) return 0; if (!get_pteptr(&init_mm, address, &kpte, &kpmd)) return -EINVAL; __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0); wmb(); flush_tlb_page(NULL, address); pte_unmap(kpte); return 0; } /* * Change the page attributes of an page in the linear mapping. * * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY */ static int change_page_attr(struct page *page, int numpages, pgprot_t prot) { int i, err = 0; unsigned long flags; local_irq_save(flags); for (i = 0; i < numpages; i++, page++) { err = __change_page_attr(page, prot); if (err) break; } local_irq_restore(flags); return err; } void __kernel_map_pages(struct page *page, int numpages, int enable) { if (PageHighMem(page)) return; change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0)); } #endif /* CONFIG_DEBUG_PAGEALLOC */ static int fixmaps; void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags) { unsigned long address = __fix_to_virt(idx); if (idx >= __end_of_fixed_addresses) { BUG(); return; } map_page(address, phys, pgprot_val(flags)); fixmaps++; } void __this_fixmap_does_not_exist(void) { WARN_ON(1); }