linux_dsm_epyc7002/arch/arc/mm/init.c
Noam Camus d6579e99bc ARC: support external initrd
Currently ARC only supports embedded initrd. This patch enables
external ones too.

[vgupta: Changed from "rt_start"=start/"rd_size"=sz to unified "initrd"=start,sz]
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-26 14:31:27 +05:30

155 lines
4.2 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_BLK_DEV_INITRD
#include <linux/initrd.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));
}
#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] = { 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 = max_low_pfn - min_low_pfn;
/*------------- reserve kernel image -----------------------*/
memblock_reserve(CONFIG_LINUX_LINK_BASE,
__pa(_end) - CONFIG_LINUX_LINK_BASE);
#ifdef CONFIG_BLK_DEV_INITRD
/*------------- reserve initrd image -----------------------*/
if (initrd_start)
memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
#endif
memblock_dump_all();
/*-------------- node setup --------------------------------*/
memset(zones_size, 0, sizeof(zones_size));
zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
/*
* 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)
{
high_memory = (void *)(CONFIG_LINUX_LINK_BASE + arc_mem_sz);
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