diff options
Diffstat (limited to 'arch/ppc/mm/init.c')
| -rw-r--r-- | arch/ppc/mm/init.c | 667 |
1 files changed, 667 insertions, 0 deletions
diff --git a/arch/ppc/mm/init.c b/arch/ppc/mm/init.c new file mode 100644 index 000000000000..be02a7fec2b7 --- /dev/null +++ b/arch/ppc/mm/init.c @@ -0,0 +1,667 @@ +/* + * PowerPC version + * 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 + * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). + * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) + * + * 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 <linux/config.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/stddef.h> +#include <linux/init.h> +#include <linux/bootmem.h> +#include <linux/highmem.h> +#include <linux/initrd.h> +#include <linux/pagemap.h> + +#include <asm/pgalloc.h> +#include <asm/prom.h> +#include <asm/io.h> +#include <asm/mmu_context.h> +#include <asm/pgtable.h> +#include <asm/mmu.h> +#include <asm/smp.h> +#include <asm/machdep.h> +#include <asm/btext.h> +#include <asm/tlb.h> +#include <asm/bootinfo.h> + +#include "mem_pieces.h" +#include "mmu_decl.h" + +#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL) +/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */ +#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE)) +#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL" +#endif +#endif +#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE + +DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); + +unsigned long total_memory; +unsigned long total_lowmem; + +unsigned long ppc_memstart; +unsigned long ppc_memoffset = PAGE_OFFSET; + +int mem_init_done; +int init_bootmem_done; +int boot_mapsize; +#ifdef CONFIG_PPC_PMAC +unsigned long agp_special_page; +#endif + +extern char _end[]; +extern char etext[], _stext[]; +extern char __init_begin, __init_end; +extern char __prep_begin, __prep_end; +extern char __chrp_begin, __chrp_end; +extern char __pmac_begin, __pmac_end; +extern char __openfirmware_begin, __openfirmware_end; + +#ifdef CONFIG_HIGHMEM +pte_t *kmap_pte; +pgprot_t kmap_prot; + +EXPORT_SYMBOL(kmap_prot); +EXPORT_SYMBOL(kmap_pte); +#endif + +void MMU_init(void); +void set_phys_avail(unsigned long total_ram); + +/* XXX should be in current.h -- paulus */ +extern struct task_struct *current_set[NR_CPUS]; + +char *klimit = _end; +struct mem_pieces phys_avail; + +extern char *sysmap; +extern unsigned long sysmap_size; + +/* + * this tells the system to map all of ram with the segregs + * (i.e. page tables) instead of the bats. + * -- Cort + */ +int __map_without_bats; +int __map_without_ltlbs; + +/* max amount of RAM to use */ +unsigned long __max_memory; +/* max amount of low RAM to map in */ +unsigned long __max_low_memory = MAX_LOW_MEM; + +void show_mem(void) +{ + int i,free = 0,total = 0,reserved = 0; + int shared = 0, cached = 0; + int highmem = 0; + + printk("Mem-info:\n"); + show_free_areas(); + printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); + i = max_mapnr; + while (i-- > 0) { + total++; + if (PageHighMem(mem_map+i)) + highmem++; + if (PageReserved(mem_map+i)) + reserved++; + else if (PageSwapCache(mem_map+i)) + cached++; + else if (!page_count(mem_map+i)) + free++; + else + shared += page_count(mem_map+i) - 1; + } + printk("%d pages of RAM\n",total); + printk("%d pages of HIGHMEM\n", highmem); + printk("%d free pages\n",free); + printk("%d reserved pages\n",reserved); + printk("%d pages shared\n",shared); + printk("%d pages swap cached\n",cached); +} + +/* Free up now-unused memory */ +static void free_sec(unsigned long start, unsigned long end, const char *name) +{ + unsigned long cnt = 0; + + while (start < end) { + ClearPageReserved(virt_to_page(start)); + set_page_count(virt_to_page(start), 1); + free_page(start); + cnt++; + start += PAGE_SIZE; + } + if (cnt) { + printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name); + totalram_pages += cnt; + } +} + +void free_initmem(void) +{ +#define FREESEC(TYPE) \ + free_sec((unsigned long)(&__ ## TYPE ## _begin), \ + (unsigned long)(&__ ## TYPE ## _end), \ + #TYPE); + + printk ("Freeing unused kernel memory:"); + FREESEC(init); + if (_machine != _MACH_Pmac) + FREESEC(pmac); + if (_machine != _MACH_chrp) + FREESEC(chrp); + if (_machine != _MACH_prep) + FREESEC(prep); + if (!have_of) + FREESEC(openfirmware); + printk("\n"); +#undef FREESEC +} + +#ifdef CONFIG_BLK_DEV_INITRD +void free_initrd_mem(unsigned long start, unsigned long end) +{ + printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); + + for (; start < end; start += PAGE_SIZE) { + ClearPageReserved(virt_to_page(start)); + set_page_count(virt_to_page(start), 1); + free_page(start); + totalram_pages++; + } +} +#endif + +/* + * Check for command-line options that affect what MMU_init will do. + */ +void MMU_setup(void) +{ + /* Check for nobats option (used in mapin_ram). */ + if (strstr(cmd_line, "nobats")) { + __map_without_bats = 1; + } + + if (strstr(cmd_line, "noltlbs")) { + __map_without_ltlbs = 1; + } + + /* Look for mem= option on command line */ + if (strstr(cmd_line, "mem=")) { + char *p, *q; + unsigned long maxmem = 0; + + for (q = cmd_line; (p = strstr(q, "mem=")) != 0; ) { + q = p + 4; + if (p > cmd_line && p[-1] != ' ') + continue; + maxmem = simple_strtoul(q, &q, 0); + if (*q == 'k' || *q == 'K') { + maxmem <<= 10; + ++q; + } else if (*q == 'm' || *q == 'M') { + maxmem <<= 20; + ++q; + } + } + __max_memory = maxmem; + } +} + +/* + * MMU_init sets up the basic memory mappings for the kernel, + * including both RAM and possibly some I/O regions, + * and sets up the page tables and the MMU hardware ready to go. + */ +void __init MMU_init(void) +{ + if (ppc_md.progress) + ppc_md.progress("MMU:enter", 0x111); + + /* parse args from command line */ + MMU_setup(); + + /* + * Figure out how much memory we have, how much + * is lowmem, and how much is highmem. If we were + * passed the total memory size from the bootloader, + * just use it. + */ + if (boot_mem_size) + total_memory = boot_mem_size; + else + total_memory = ppc_md.find_end_of_memory(); + + if (__max_memory && total_memory > __max_memory) + total_memory = __max_memory; + total_lowmem = total_memory; +#ifdef CONFIG_FSL_BOOKE + /* Freescale Book-E parts expect lowmem to be mapped by fixed TLB + * entries, so we need to adjust lowmem to match the amount we can map + * in the fixed entries */ + adjust_total_lowmem(); +#endif /* CONFIG_FSL_BOOKE */ + if (total_lowmem > __max_low_memory) { + total_lowmem = __max_low_memory; +#ifndef CONFIG_HIGHMEM + total_memory = total_lowmem; +#endif /* CONFIG_HIGHMEM */ + } + set_phys_avail(total_lowmem); + + /* Initialize the MMU hardware */ + if (ppc_md.progress) + ppc_md.progress("MMU:hw init", 0x300); + MMU_init_hw(); + + /* Map in all of RAM starting at KERNELBASE */ + if (ppc_md.progress) + ppc_md.progress("MMU:mapin", 0x301); + mapin_ram(); + +#ifdef CONFIG_HIGHMEM + ioremap_base = PKMAP_BASE; +#else + ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ +#endif /* CONFIG_HIGHMEM */ + ioremap_bot = ioremap_base; + + /* Map in I/O resources */ + if (ppc_md.progress) + ppc_md.progress("MMU:setio", 0x302); + if (ppc_md.setup_io_mappings) + ppc_md.setup_io_mappings(); + + /* Initialize the context management stuff */ + mmu_context_init(); + + if (ppc_md.progress) + ppc_md.progress("MMU:exit", 0x211); + +#ifdef CONFIG_BOOTX_TEXT + /* By default, we are no longer mapped */ + boot_text_mapped = 0; + /* Must be done last, or ppc_md.progress will die. */ + map_boot_text(); +#endif +} + +/* This is only called until mem_init is done. */ +void __init *early_get_page(void) +{ + void *p; + + if (init_bootmem_done) { + p = alloc_bootmem_pages(PAGE_SIZE); + } else { + p = mem_pieces_find(PAGE_SIZE, PAGE_SIZE); + } + return p; +} + +/* + * Initialize the bootmem system and give it all the memory we + * have available. + */ +void __init do_init_bootmem(void) +{ + unsigned long start, size; + int i; + + /* + * Find an area to use for the bootmem bitmap. + * We look for the first area which is at least + * 128kB in length (128kB is enough for a bitmap + * for 4GB of memory, using 4kB pages), plus 1 page + * (in case the address isn't page-aligned). + */ + start = 0; + size = 0; + for (i = 0; i < phys_avail.n_regions; ++i) { + unsigned long a = phys_avail.regions[i].address; + unsigned long s = phys_avail.regions[i].size; + if (s <= size) + continue; + start = a; + size = s; + if (s >= 33 * PAGE_SIZE) + break; + } + start = PAGE_ALIGN(start); + + min_low_pfn = start >> PAGE_SHIFT; + max_low_pfn = (PPC_MEMSTART + total_lowmem) >> PAGE_SHIFT; + max_pfn = (PPC_MEMSTART + total_memory) >> PAGE_SHIFT; + boot_mapsize = init_bootmem_node(&contig_page_data, min_low_pfn, + PPC_MEMSTART >> PAGE_SHIFT, + max_low_pfn); + + /* remove the bootmem bitmap from the available memory */ + mem_pieces_remove(&phys_avail, start, boot_mapsize, 1); + + /* add everything in phys_avail into the bootmem map */ + for (i = 0; i < phys_avail.n_regions; ++i) + free_bootmem(phys_avail.regions[i].address, + phys_avail.regions[i].size); + + init_bootmem_done = 1; +} + +/* + * paging_init() sets up the page tables - in fact we've already done this. + */ +void __init paging_init(void) +{ + unsigned long zones_size[MAX_NR_ZONES], i; + +#ifdef CONFIG_HIGHMEM + map_page(PKMAP_BASE, 0, 0); /* XXX gross */ + pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k + (PKMAP_BASE), PKMAP_BASE), PKMAP_BASE); + map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */ + kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k + (KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN); + kmap_prot = PAGE_KERNEL; +#endif /* CONFIG_HIGHMEM */ + + /* + * All pages are DMA-able so we put them all in the DMA zone. + */ + zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT; + for (i = 1; i < MAX_NR_ZONES; i++) + zones_size[i] = 0; + +#ifdef CONFIG_HIGHMEM + zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT; +#endif /* CONFIG_HIGHMEM */ + + free_area_init(zones_size); +} + +void __init mem_init(void) +{ + unsigned long addr; + int codepages = 0; + int datapages = 0; + int initpages = 0; +#ifdef CONFIG_HIGHMEM + unsigned long highmem_mapnr; + + highmem_mapnr = total_lowmem >> PAGE_SHIFT; +#endif /* CONFIG_HIGHMEM */ + max_mapnr = total_memory >> PAGE_SHIFT; + + high_memory = (void *) __va(PPC_MEMSTART + total_lowmem); + num_physpages = max_mapnr; /* RAM is assumed contiguous */ + + totalram_pages += free_all_bootmem(); + +#ifdef CONFIG_BLK_DEV_INITRD + /* if we are booted from BootX with an initial ramdisk, + make sure the ramdisk pages aren't reserved. */ + if (initrd_start) { + for (addr = initrd_start; addr < initrd_end; addr += PAGE_SIZE) + ClearPageReserved(virt_to_page(addr)); + } +#endif /* CONFIG_BLK_DEV_INITRD */ + +#ifdef CONFIG_PPC_OF + /* mark the RTAS pages as reserved */ + if ( rtas_data ) + for (addr = (ulong)__va(rtas_data); + addr < PAGE_ALIGN((ulong)__va(rtas_data)+rtas_size) ; + addr += PAGE_SIZE) + SetPageReserved(virt_to_page(addr)); +#endif +#ifdef CONFIG_PPC_PMAC + if (agp_special_page) + SetPageReserved(virt_to_page(agp_special_page)); +#endif + if ( sysmap ) + for (addr = (unsigned long)sysmap; + addr < PAGE_ALIGN((unsigned long)sysmap+sysmap_size) ; + addr += PAGE_SIZE) + SetPageReserved(virt_to_page(addr)); + + for (addr = PAGE_OFFSET; addr < (unsigned long)high_memory; + addr += PAGE_SIZE) { + if (!PageReserved(virt_to_page(addr))) + continue; + if (addr < (ulong) etext) + codepages++; + else if (addr >= (unsigned long)&__init_begin + && addr < (unsigned long)&__init_end) + initpages++; + else if (addr < (ulong) klimit) + datapages++; + } + +#ifdef CONFIG_HIGHMEM + { + unsigned long pfn; + + for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { + struct page *page = mem_map + pfn; + + ClearPageReserved(page); + set_bit(PG_highmem, &page->flags); + set_page_count(page, 1); + __free_page(page); + totalhigh_pages++; + } + totalram_pages += totalhigh_pages; + } +#endif /* CONFIG_HIGHMEM */ + + printk("Memory: %luk available (%dk kernel code, %dk data, %dk init, %ldk highmem)\n", + (unsigned long)nr_free_pages()<< (PAGE_SHIFT-10), + codepages<< (PAGE_SHIFT-10), datapages<< (PAGE_SHIFT-10), + initpages<< (PAGE_SHIFT-10), + (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); + if (sysmap) + printk("System.map loaded at 0x%08x for debugger, size: %ld bytes\n", + (unsigned int)sysmap, sysmap_size); +#ifdef CONFIG_PPC_PMAC + if (agp_special_page) + printk(KERN_INFO "AGP special page: 0x%08lx\n", agp_special_page); +#endif + + mem_init_done = 1; +} + +/* + * Set phys_avail to the amount of physical memory, + * less the kernel text/data/bss. + */ +void __init +set_phys_avail(unsigned long total_memory) +{ + unsigned long kstart, ksize; + + /* + * Initially, available physical memory is equivalent to all + * physical memory. + */ + + phys_avail.regions[0].address = PPC_MEMSTART; + phys_avail.regions[0].size = total_memory; + phys_avail.n_regions = 1; + + /* + * Map out the kernel text/data/bss from the available physical + * memory. + */ + + kstart = __pa(_stext); /* should be 0 */ + ksize = PAGE_ALIGN(klimit - _stext); + + mem_pieces_remove(&phys_avail, kstart, ksize, 0); + mem_pieces_remove(&phys_avail, 0, 0x4000, 0); + +#if defined(CONFIG_BLK_DEV_INITRD) + /* Remove the init RAM disk from the available memory. */ + if (initrd_start) { + mem_pieces_remove(&phys_avail, __pa(initrd_start), + initrd_end - initrd_start, 1); + } +#endif /* CONFIG_BLK_DEV_INITRD */ +#ifdef CONFIG_PPC_OF + /* remove the RTAS pages from the available memory */ + if (rtas_data) + mem_pieces_remove(&phys_avail, rtas_data, rtas_size, 1); +#endif + /* remove the sysmap pages from the available memory */ + if (sysmap) + mem_pieces_remove(&phys_avail, __pa(sysmap), sysmap_size, 1); +#ifdef CONFIG_PPC_PMAC + /* Because of some uninorth weirdness, we need a page of + * memory as high as possible (it must be outside of the + * bus address seen as the AGP aperture). It will be used + * by the r128 DRM driver + * + * FIXME: We need to make sure that page doesn't overlap any of the\ + * above. This could be done by improving mem_pieces_find to be able + * to do a backward search from the end of the list. + */ + if (_machine == _MACH_Pmac && find_devices("uni-north-agp")) { + agp_special_page = (total_memory - PAGE_SIZE); + mem_pieces_remove(&phys_avail, agp_special_page, PAGE_SIZE, 0); + agp_special_page = (unsigned long)__va(agp_special_page); + } +#endif /* CONFIG_PPC_PMAC */ +} + +/* Mark some memory as reserved by removing it from phys_avail. */ +void __init reserve_phys_mem(unsigned long start, unsigned long size) +{ + mem_pieces_remove(&phys_avail, start, size, 1); +} + +/* + * This is called when a page has been modified by the kernel. + * It just marks the page as not i-cache clean. We do the i-cache + * flush later when the page is given to a user process, if necessary. + */ +void flush_dcache_page(struct page *page) +{ + clear_bit(PG_arch_1, &page->flags); +} + +void flush_dcache_icache_page(struct page *page) +{ +#ifdef CONFIG_BOOKE + __flush_dcache_icache(kmap(page)); + kunmap(page); +#else + __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); +#endif + +} +void clear_user_page(void *page, unsigned long vaddr, struct page *pg) +{ + clear_page(page); + clear_bit(PG_arch_1, &pg->flags); +} + +void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, + struct page *pg) +{ + copy_page(vto, vfrom); + clear_bit(PG_arch_1, &pg->flags); +} + +void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, + unsigned long addr, int len) +{ + unsigned long maddr; + + maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); + flush_icache_range(maddr, maddr + len); + kunmap(page); +} + +/* + * This is called at the end of handling a user page fault, when the + * fault has been handled by updating a PTE in the linux page tables. + * We use it to preload an HPTE into the hash table corresponding to + * the updated linux PTE. + */ +void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, + pte_t pte) +{ + /* handle i-cache coherency */ + unsigned long pfn = pte_pfn(pte); + + if (pfn_valid(pfn)) { + struct page *page = pfn_to_page(pfn); + if (!PageReserved(page) + && !test_bit(PG_arch_1, &page->flags)) { + if (vma->vm_mm == current->active_mm) + __flush_dcache_icache((void *) address); + else + flush_dcache_icache_page(page); + set_bit(PG_arch_1, &page->flags); + } + } + +#ifdef CONFIG_PPC_STD_MMU + /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ + if (Hash != 0 && pte_young(pte)) { + struct mm_struct *mm; + pmd_t *pmd; + + mm = (address < TASK_SIZE)? vma->vm_mm: &init_mm; + pmd = pmd_offset(pgd_offset(mm, address), address); + if (!pmd_none(*pmd)) + add_hash_page(mm->context, address, pmd_val(*pmd)); + } +#endif +} + +/* + * This is called by /dev/mem to know if a given address has to + * be mapped non-cacheable or not + */ +int page_is_ram(unsigned long pfn) +{ + unsigned long paddr = (pfn << PAGE_SHIFT); + + return paddr < __pa(high_memory); +} + +pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr, + unsigned long size, pgprot_t vma_prot) +{ + if (ppc_md.phys_mem_access_prot) + return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot); + + if (!page_is_ram(addr >> PAGE_SHIFT)) + vma_prot = __pgprot(pgprot_val(vma_prot) + | _PAGE_GUARDED | _PAGE_NO_CACHE); + return vma_prot; +} +EXPORT_SYMBOL(phys_mem_access_prot); |