linux/arch/arc/mm/init.c
Vineet Gupta 450dd430bf ARC: [DeviceTree] Convert some Kconfig items to runtime values
* mem size now runtime configured (prev CONFIG_ARC_PLAT_SDRAM_SIZE)
* core cpu clk runtime configured (prev CONFIG_ARC_PLAT_CLK)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
2013-02-15 23:15:56 +05:30

188 lines
5.2 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_BLOCK_DEV_RAM
#include <linux/blk.h>
#endif
#include <linux/swap.h>
#include <linux/module.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);
/* Default tot mem from .config */
static unsigned long arc_mem_sz = 0x20000000; /* some default */
/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
static int __init setup_mem_sz(char *str)
{
arc_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(arc_mem_sz));
return 0;
}
early_param("mem", setup_mem_sz);
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
arc_mem_sz = size & PAGE_MASK;
pr_info("Memory size set via devicetree %ldM\n", TO_MB(arc_mem_sz));
}
/*
* 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] = { 0, 0 };
unsigned long end_mem = CONFIG_LINUX_LINK_BASE + arc_mem_sz;
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;
/*
* We do it here, so that memory is correctly instantiated
* even if "mem=xxx" cmline over-ride is given and/or
* DT has memory node. Each causes an update to @arc_mem_sz
* and we finally add memory one here
*/
memblock_add(CONFIG_LINUX_LINK_BASE, arc_mem_sz);
/*------------- externs in mm need setting up ---------------*/
/* first page of system - kernel .vector starts here */
min_low_pfn = PFN_DOWN(CONFIG_LINUX_LINK_BASE);
/* Last usable page of low mem (no HIGHMEM yet for ARC port) */
max_low_pfn = max_pfn = PFN_DOWN(end_mem);
max_mapnr = num_physpages = max_low_pfn - min_low_pfn;
/*------------- reserve kernel image -----------------------*/
memblock_reserve(CONFIG_LINUX_LINK_BASE,
__pa(_end) - CONFIG_LINUX_LINK_BASE);
memblock_dump_all();
/*-------------- node setup --------------------------------*/
memset(zones_size, 0, sizeof(zones_size));
zones_size[ZONE_NORMAL] = num_physpages;
/*
* 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 */
NULL); /* NO holes */
}
/*
* mem_init - initializes memory
*
* Frees up bootmem
* Calculates and displays memory available/used
*/
void __init mem_init(void)
{
int codesize, datasize, initsize, reserved_pages, free_pages;
int tmp;
high_memory = (void *)(CONFIG_LINUX_LINK_BASE + arc_mem_sz);
totalram_pages = free_all_bootmem();
/* count all reserved pages [kernel code/data/mem_map..] */
reserved_pages = 0;
for (tmp = 0; tmp < max_mapnr; tmp++)
if (PageReserved(mem_map + tmp))
reserved_pages++;
/* XXX: nr_free_pages() is equivalent */
free_pages = max_mapnr - reserved_pages;
/*
* For the purpose of display below, split the "reserve mem"
* kernel code/data is already shown explicitly,
* Show any other reservations (mem_map[ ] et al)
*/
reserved_pages -= (((unsigned int)_end - CONFIG_LINUX_LINK_BASE) >>
PAGE_SHIFT);
codesize = _etext - _text;
datasize = _end - _etext;
initsize = __init_end - __init_begin;
pr_info("Memory Available: %dM / %ldM (%dK code, %dK data, %dK init, %dK reserv)\n",
PAGES_TO_MB(free_pages),
TO_MB(arc_mem_sz),
TO_KB(codesize), TO_KB(datasize), TO_KB(initsize),
PAGES_TO_KB(reserved_pages));
}
static void __init free_init_pages(const char *what, unsigned long begin,
unsigned long end)
{
unsigned long addr;
pr_info("Freeing %s: %ldk [%lx] to [%lx]\n",
what, TO_KB(end - begin), begin, end);
/* need to check that the page we free is not a partial page */
for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
}
/*
* free_initmem: Free all the __init memory.
*/
void __init_refok free_initmem(void)
{
free_init_pages("unused kernel memory",
(unsigned long)__init_begin,
(unsigned long)__init_end);
}
#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
free_init_pages("initrd memory", start, end);
}
#endif
#ifdef CONFIG_OF_FLATTREE
void __init early_init_dt_setup_initrd_arch(unsigned long start,
unsigned long end)
{
pr_err("%s(%lx, %lx)\n", __func__, start, end);
}
#endif /* CONFIG_OF_FLATTREE */