swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 1860e379875dfe7271c649058aeddffe5afd9d0d authored by Linus Torvalds on 08 June 2014, 18:19:54 UTC
Linux 3.15
Linux 3.15
Tip revision: 1860e37
init.c
/*
* Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/bootmem.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/memblock.h>
#include <linux/mm.h> /* mem_init */
#include <linux/initrd.h>
#include <linux/pagemap.h>
#include <linux/pfn.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/export.h>
#include <asm/page.h>
#include <asm/mmu_context.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
#include <asm/tlb.h>
#include <asm/fixmap.h>
/* Use for MMU and noMMU because of PCI generic code */
int mem_init_done;
#ifndef CONFIG_MMU
unsigned int __page_offset;
EXPORT_SYMBOL(__page_offset);
#else
static int init_bootmem_done;
#endif /* CONFIG_MMU */
char *klimit = _end;
/*
* Initialize the bootmem system and give it all the memory we
* have available.
*/
unsigned long memory_start;
EXPORT_SYMBOL(memory_start);
unsigned long memory_size;
EXPORT_SYMBOL(memory_size);
unsigned long lowmem_size;
#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
EXPORT_SYMBOL(kmap_pte);
pgprot_t kmap_prot;
EXPORT_SYMBOL(kmap_prot);
static inline pte_t *virt_to_kpte(unsigned long vaddr)
{
return pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr),
vaddr), vaddr);
}
static void __init highmem_init(void)
{
pr_debug("%x\n", (u32)PKMAP_BASE);
map_page(PKMAP_BASE, 0, 0); /* XXX gross */
pkmap_page_table = virt_to_kpte(PKMAP_BASE);
kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
kmap_prot = PAGE_KERNEL;
}
static void highmem_setup(void)
{
unsigned long pfn;
for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
struct page *page = pfn_to_page(pfn);
/* FIXME not sure about */
if (!memblock_is_reserved(pfn << PAGE_SHIFT))
free_highmem_page(page);
}
}
#endif /* CONFIG_HIGHMEM */
/*
* paging_init() sets up the page tables - in fact we've already done this.
*/
static void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES];
#ifdef CONFIG_MMU
int idx;
/* Setup fixmaps */
for (idx = 0; idx < __end_of_fixed_addresses; idx++)
clear_fixmap(idx);
#endif
/* Clean every zones */
memset(zones_size, 0, sizeof(zones_size));
#ifdef CONFIG_HIGHMEM
highmem_init();
zones_size[ZONE_DMA] = max_low_pfn;
zones_size[ZONE_HIGHMEM] = max_pfn;
#else
zones_size[ZONE_DMA] = max_pfn;
#endif
/* We don't have holes in memory map */
free_area_init_nodes(zones_size);
}
void __init setup_memory(void)
{
unsigned long map_size;
struct memblock_region *reg;
#ifndef CONFIG_MMU
u32 kernel_align_start, kernel_align_size;
/* Find main memory where is the kernel */
for_each_memblock(memory, reg) {
memory_start = (u32)reg->base;
lowmem_size = reg->size;
if ((memory_start <= (u32)_text) &&
((u32)_text <= (memory_start + lowmem_size - 1))) {
memory_size = lowmem_size;
PAGE_OFFSET = memory_start;
pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
__func__, (u32) memory_start,
(u32) memory_size);
break;
}
}
if (!memory_start || !memory_size) {
panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
__func__, (u32) memory_start, (u32) memory_size);
}
/* reservation of region where is the kernel */
kernel_align_start = PAGE_DOWN((u32)_text);
/* ALIGN can be remove because _end in vmlinux.lds.S is align */
kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
__func__, kernel_align_start, kernel_align_start
+ kernel_align_size, kernel_align_size);
memblock_reserve(kernel_align_start, kernel_align_size);
#endif
/*
* Kernel:
* start: base phys address of kernel - page align
* end: base phys address of kernel - page align
*
* min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
* max_low_pfn
* max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
*/
/* memory start is from the kernel end (aligned) to higher addr */
min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
/* RAM is assumed contiguous */
max_mapnr = memory_size >> PAGE_SHIFT;
max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
/*
* 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).
*/
map_size = init_bootmem_node(NODE_DATA(0),
PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
/* Add active regions with valid PFNs */
for_each_memblock(memory, reg) {
unsigned long start_pfn, end_pfn;
start_pfn = memblock_region_memory_base_pfn(reg);
end_pfn = memblock_region_memory_end_pfn(reg);
memblock_set_node(start_pfn << PAGE_SHIFT,
(end_pfn - start_pfn) << PAGE_SHIFT,
&memblock.memory, 0);
}
/* free bootmem is whole main memory */
free_bootmem_with_active_regions(0, max_low_pfn);
/* reserve allocate blocks */
for_each_memblock(reserved, reg) {
unsigned long top = reg->base + reg->size - 1;
pr_debug("reserved - 0x%08x-0x%08x, %lx, %lx\n",
(u32) reg->base, (u32) reg->size, top,
memory_start + lowmem_size - 1);
if (top <= (memory_start + lowmem_size - 1)) {
reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
} else if (reg->base < (memory_start + lowmem_size - 1)) {
unsigned long trunc_size = memory_start + lowmem_size -
reg->base;
reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
}
}
/* XXX need to clip this if using highmem? */
sparse_memory_present_with_active_regions(0);
#ifdef CONFIG_MMU
init_bootmem_done = 1;
#endif
paging_init();
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
free_reserved_area((void *)start, (void *)end, -1, "initrd");
}
#endif
void free_initmem(void)
{
free_initmem_default(-1);
}
void __init mem_init(void)
{
high_memory = (void *)__va(memory_start + lowmem_size - 1);
/* this will put all memory onto the freelists */
free_all_bootmem();
#ifdef CONFIG_HIGHMEM
highmem_setup();
#endif
mem_init_print_info(NULL);
#ifdef CONFIG_MMU
pr_info("Kernel virtual memory layout:\n");
pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
#ifdef CONFIG_HIGHMEM
pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
#endif /* CONFIG_HIGHMEM */
pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
ioremap_bot, ioremap_base);
pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
(unsigned long)VMALLOC_START, VMALLOC_END);
#endif
mem_init_done = 1;
}
#ifndef CONFIG_MMU
int page_is_ram(unsigned long pfn)
{
return __range_ok(pfn, 0);
}
#else
int page_is_ram(unsigned long pfn)
{
return pfn < max_low_pfn;
}
/*
* Check for command-line options that affect what MMU_init will do.
*/
static void mm_cmdline_setup(void)
{
unsigned long maxmem = 0;
char *p = cmd_line;
/* Look for mem= option on command line */
p = strstr(cmd_line, "mem=");
if (p) {
p += 4;
maxmem = memparse(p, &p);
if (maxmem && memory_size > maxmem) {
memory_size = maxmem;
memblock.memory.regions[0].size = memory_size;
}
}
}
/*
* MMU_init_hw does the chip-specific initialization of the MMU hardware.
*/
static void __init mmu_init_hw(void)
{
/*
* The Zone Protection Register (ZPR) defines how protection will
* be applied to every page which is a member of a given zone. At
* present, we utilize only two of the zones.
* The zone index bits (of ZSEL) in the PTE are used for software
* indicators, except the LSB. For user access, zone 1 is used,
* for kernel access, zone 0 is used. We set all but zone 1
* to zero, allowing only kernel access as indicated in the PTE.
* For zone 1, we set a 01 binary (a value of 10 will not work)
* to allow user access as indicated in the PTE. This also allows
* kernel access as indicated in the PTE.
*/
__asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
"mts rzpr, r11;"
: : : "r11");
}
/*
* 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.
*/
/* called from head.S */
asmlinkage void __init mmu_init(void)
{
unsigned int kstart, ksize;
if (!memblock.reserved.cnt) {
pr_emerg("Error memory count\n");
machine_restart(NULL);
}
if ((u32) memblock.memory.regions[0].size < 0x400000) {
pr_emerg("Memory must be greater than 4MB\n");
machine_restart(NULL);
}
if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
pr_emerg("Kernel size is greater than memory node\n");
machine_restart(NULL);
}
/* Find main memory where the kernel is */
memory_start = (u32) memblock.memory.regions[0].base;
lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
if (lowmem_size > CONFIG_LOWMEM_SIZE) {
lowmem_size = CONFIG_LOWMEM_SIZE;
#ifndef CONFIG_HIGHMEM
memory_size = lowmem_size;
#endif
}
mm_cmdline_setup(); /* FIXME parse args from command line - not used */
/*
* Map out the kernel text/data/bss from the available physical
* memory.
*/
kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
/* kernel size */
ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
memblock_reserve(kstart, ksize);
#if defined(CONFIG_BLK_DEV_INITRD)
/* Remove the init RAM disk from the available memory. */
if (initrd_start) {
unsigned long size;
size = initrd_end - initrd_start;
memblock_reserve(__virt_to_phys(initrd_start), size);
}
#endif /* CONFIG_BLK_DEV_INITRD */
/* Initialize the MMU hardware */
mmu_init_hw();
/* Map in all of RAM starting at CONFIG_KERNEL_START */
mapin_ram();
/* Extend vmalloc and ioremap area as big as possible */
#ifdef CONFIG_HIGHMEM
ioremap_base = ioremap_bot = PKMAP_BASE;
#else
ioremap_base = ioremap_bot = FIXADDR_START;
#endif
/* Initialize the context management stuff */
mmu_context_init();
/* Shortly after that, the entire linear mapping will be available */
/* This will also cause that unflatten device tree will be allocated
* inside 768MB limit */
memblock_set_current_limit(memory_start + lowmem_size - 1);
}
/* 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 {
/*
* Mem start + kernel_tlb -> here is limit
* because of mem mapping from head.S
*/
p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
memory_start + kernel_tlb));
}
return p;
}
#endif /* CONFIG_MMU */
void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
{
if (mem_init_done)
return kmalloc(size, mask);
else
return alloc_bootmem(size);
}
void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
{
void *p;
if (mem_init_done)
p = kzalloc(size, mask);
else {
p = alloc_bootmem(size);
if (p)
memset(p, 0, size);
}
return p;
}