linux-sg2042/arch/xtensa/mm/init.c

192 lines
4.1 KiB
C

/*
* arch/xtensa/mm/init.c
*
* Derived from MIPS, PPC.
*
* 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.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
* Copyright (C) 2014 - 2016 Cadence Design Systems Inc.
*
* Chris Zankel <chris@zankel.net>
* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
* Marc Gauthier
* Kevin Chea
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/bootmem.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/of_fdt.h>
#include <linux/dma-contiguous.h>
#include <asm/bootparam.h>
#include <asm/page.h>
#include <asm/sections.h>
#include <asm/sysmem.h>
/*
* Initialize the bootmem system and give it all low memory we have available.
*/
void __init bootmem_init(void)
{
/* Reserve all memory below PHYS_OFFSET, as memory
* accounting doesn't work for pages below that address.
*
* If PHYS_OFFSET is zero reserve page at address 0:
* successfull allocations should never return NULL.
*/
if (PHYS_OFFSET)
memblock_reserve(0, PHYS_OFFSET);
else
memblock_reserve(0, 1);
early_init_fdt_scan_reserved_mem();
if (!memblock_phys_mem_size())
panic("No memory found!\n");
min_low_pfn = PFN_UP(memblock_start_of_DRAM());
min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET));
max_pfn = PFN_DOWN(memblock_end_of_DRAM());
max_low_pfn = min(max_pfn, MAX_LOW_PFN);
memblock_set_current_limit(PFN_PHYS(max_low_pfn));
dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
memblock_dump_all();
}
void __init zones_init(void)
{
/* All pages are DMA-able, so we put them all in the DMA zone. */
unsigned long zones_size[MAX_NR_ZONES] = {
[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
#ifdef CONFIG_HIGHMEM
[ZONE_HIGHMEM] = max_pfn - max_low_pfn,
#endif
};
free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
}
/*
* Initialize memory pages.
*/
void __init mem_init(void)
{
#ifdef CONFIG_HIGHMEM
unsigned long tmp;
reset_all_zones_managed_pages();
for (tmp = max_low_pfn; tmp < max_pfn; tmp++)
free_highmem_page(pfn_to_page(tmp));
#endif
max_mapnr = max_pfn - ARCH_PFN_OFFSET;
high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
free_all_bootmem();
mem_init_print_info(NULL);
pr_info("virtual kernel memory layout:\n"
#ifdef CONFIG_HIGHMEM
" pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
" fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
#endif
#ifdef CONFIG_MMU
" vmalloc : 0x%08lx - 0x%08lx (%5lu MB)\n"
#endif
" lowmem : 0x%08lx - 0x%08lx (%5lu MB)\n",
#ifdef CONFIG_HIGHMEM
PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
(LAST_PKMAP*PAGE_SIZE) >> 10,
FIXADDR_START, FIXADDR_TOP,
(FIXADDR_TOP - FIXADDR_START) >> 10,
#endif
#ifdef CONFIG_MMU
VMALLOC_START, VMALLOC_END,
(VMALLOC_END - VMALLOC_START) >> 20,
PAGE_OFFSET, PAGE_OFFSET +
(max_low_pfn - min_low_pfn) * PAGE_SIZE,
#else
min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
#endif
((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
}
#ifdef CONFIG_BLK_DEV_INITRD
extern int initrd_is_mapped;
void free_initrd_mem(unsigned long start, unsigned long end)
{
if (initrd_is_mapped)
free_reserved_area((void *)start, (void *)end, -1, "initrd");
}
#endif
void free_initmem(void)
{
free_initmem_default(-1);
}
static void __init parse_memmap_one(char *p)
{
char *oldp;
unsigned long start_at, mem_size;
if (!p)
return;
oldp = p;
mem_size = memparse(p, &p);
if (p == oldp)
return;
switch (*p) {
case '@':
start_at = memparse(p + 1, &p);
memblock_add(start_at, mem_size);
break;
case '$':
start_at = memparse(p + 1, &p);
memblock_reserve(start_at, mem_size);
break;
case 0:
memblock_reserve(mem_size, -mem_size);
break;
default:
pr_warn("Unrecognized memmap syntax: %s\n", p);
break;
}
}
static int __init parse_memmap_opt(char *str)
{
while (str) {
char *k = strchr(str, ',');
if (k)
*k++ = 0;
parse_memmap_one(str);
str = k;
}
return 0;
}
early_param("memmap", parse_memmap_opt);