// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/initrd.h>
#endif
#include <linux/of_fdt.h>
#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_RAM_BASE;
static unsigned long low_mem_sz;
#ifdef CONFIG_HIGHMEM
static unsigned long min_high_pfn, max_high_pfn;
static u64 high_mem_start;
static u64 high_mem_sz;
#endif
#ifdef CONFIG_DISCONTIGMEM
struct pglist_data node_data[MAX_NUMNODES] __read_mostly;
EXPORT_SYMBOL(node_data);
#endif
long __init arc_get_mem_sz(void)
{
return low_mem_sz;
}
/* 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_RAM_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":"");
}
/*
* 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_FLATMEM
/* pfn_valid() uses this */
max_mapnr = max_low_pfn - min_low_pfn;
#endif
/*------------- 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_node(low_mem_start, low_mem_sz, 0);
memblock_reserve(CONFIG_LINUX_LINK_BASE,
__pa(_end) - CONFIG_LINUX_LINK_BASE);
#ifdef CONFIG_BLK_DEV_INITRD
if (phys_initrd_size) {
memblock_reserve(phys_initrd_start, phys_initrd_size);
initrd_start = (unsigned long)__va(phys_initrd_start);
initrd_end = initrd_start + phys_initrd_size;
}
#endif
early_init_fdt_reserve_self();
early_init_fdt_scan_reserved_mem();
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;
/*
* 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_RAM_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
/*
* Populate a new node with highmem
*
* On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
* than addresses in normal ala low memory (0x8000_0000 based).
* Even with PAE, the huge peripheral space hole would waste a lot of
* mem with single mem_map[]. This warrants a mem_map per region design.
* Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM.
*
* DISCONTIGMEM in turns requires multiple nodes. node 0 above is
* populated with normal memory zone while node 1 only has highmem
*/
node_set_online(1);
min_high_pfn = PFN_DOWN(high_mem_start);
max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
zones_size[ZONE_NORMAL] = 0;
zones_holes[ZONE_NORMAL] = 0;
zones_size[ZONE_HIGHMEM] = max_high_pfn - min_high_pfn;
zones_holes[ZONE_HIGHMEM] = 0;
free_area_init_node(1, /* node-id */
zones_size, /* num pages per zone */
min_high_pfn, /* first pfn of node */
zones_holes); /* holes */
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_high_pfn; tmp++)
free_highmem_page(pfn_to_page(tmp));
#endif
memblock_free_all();
mem_init_print_info(NULL);
}
