WSL2-Linux-Kernel/arch/arc/mm/init.c

206 строки
5.1 KiB
C

/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/memblock.h>
#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/initrd.h>
#endif
#include <linux/swap.h>
#include <linux/module.h>
#include <linux/highmem.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
#include <asm/arcregs.h>
pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
EXPORT_SYMBOL(empty_zero_page);
static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE;
static unsigned long low_mem_sz;
#ifdef CONFIG_HIGHMEM
static unsigned long min_high_pfn;
static u64 high_mem_start;
static u64 high_mem_sz;
#endif
/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
static int __init setup_mem_sz(char *str)
{
low_mem_sz = memparse(str, NULL) & PAGE_MASK;
/* early console might not be setup yet - it will show up later */
pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz));
return 0;
}
early_param("mem", setup_mem_sz);
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
int in_use = 0;
if (!low_mem_sz) {
if (base != low_mem_start)
panic("CONFIG_LINUX_LINK_BASE != DT memory { }");
low_mem_sz = size;
in_use = 1;
} else {
#ifdef CONFIG_HIGHMEM
high_mem_start = base;
high_mem_sz = size;
in_use = 1;
#endif
}
pr_info("Memory @ %llx [%lldM] %s\n",
base, TO_MB(size), !in_use ? "Not used":"");
}
#ifdef CONFIG_BLK_DEV_INITRD
static int __init early_initrd(char *p)
{
unsigned long start, size;
char *endp;
start = memparse(p, &endp);
if (*endp == ',') {
size = memparse(endp + 1, NULL);
initrd_start = (unsigned long)__va(start);
initrd_end = (unsigned long)__va(start + size);
}
return 0;
}
early_param("initrd", early_initrd);
#endif
/*
* First memory setup routine called from setup_arch()
* 1. setup swapper's mm @init_mm
* 2. Count the pages we have and setup bootmem allocator
* 3. zone setup
*/
void __init setup_arch_memory(void)
{
unsigned long zones_size[MAX_NR_ZONES];
unsigned long zones_holes[MAX_NR_ZONES];
init_mm.start_code = (unsigned long)_text;
init_mm.end_code = (unsigned long)_etext;
init_mm.end_data = (unsigned long)_edata;
init_mm.brk = (unsigned long)_end;
/* first page of system - kernel .vector starts here */
min_low_pfn = ARCH_PFN_OFFSET;
/* Last usable page of low mem */
max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz);
#ifdef CONFIG_HIGHMEM
min_high_pfn = PFN_DOWN(high_mem_start);
max_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
#endif
max_mapnr = max_pfn - min_low_pfn;
/*------------- bootmem allocator setup -----------------------*/
/*
* seed the bootmem allocator after any DT memory node parsing or
* "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz
*
* Only low mem is added, otherwise we have crashes when allocating
* mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of
* avail memory, ending in highmem with a > 32-bit address. However
* it then tries to memset it with a truncaed 32-bit handle, causing
* the crash
*/
memblock_add(low_mem_start, low_mem_sz);
memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_start)
memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
#endif
memblock_dump_all();
/*----------------- node/zones setup --------------------------*/
memset(zones_size, 0, sizeof(zones_size));
memset(zones_holes, 0, sizeof(zones_holes));
zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
zones_holes[ZONE_NORMAL] = 0;
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
/* This handles the peripheral address space hole */
zones_holes[ZONE_HIGHMEM] = min_high_pfn - max_low_pfn;
#endif
/*
* We can't use the helper free_area_init(zones[]) because it uses
* PAGE_OFFSET to compute the @min_low_pfn which would be wrong
* when our kernel doesn't start at PAGE_OFFSET, i.e.
* PAGE_OFFSET != CONFIG_LINUX_LINK_BASE
*/
free_area_init_node(0, /* node-id */
zones_size, /* num pages per zone */
min_low_pfn, /* first pfn of node */
zones_holes); /* holes */
#ifdef CONFIG_HIGHMEM
high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
kmap_init();
#endif
}
/*
* mem_init - initializes memory
*
* Frees up bootmem
* Calculates and displays memory available/used
*/
void __init mem_init(void)
{
#ifdef CONFIG_HIGHMEM
unsigned long tmp;
reset_all_zones_managed_pages();
for (tmp = min_high_pfn; tmp < max_pfn; tmp++)
free_highmem_page(pfn_to_page(tmp));
#endif
free_all_bootmem();
mem_init_print_info(NULL);
}
/*
* free_initmem: Free all the __init memory.
*/
void __init_refok free_initmem(void)
{
free_initmem_default(-1);
}
#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
free_reserved_area((void *)start, (void *)end, -1, "initrd");
}
#endif