/*
* Handle the memory map.
* The functions here do the job until bootmem takes over.
*
* Getting sanitize_e820_map() in sync with i386 version by applying change:
* - Provisions for empty E820 memory regions (reported by certain BIOSes).
* Alex Achenbach <xela@slit.de>, December 2002.
* Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
*
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/kexec.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/pfn.h>
#include <linux/pci.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/e820.h>
#include <asm/proto.h>
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/kdebug.h>
#include <asm/trampoline.h>
/*
* PFN of last memory page.
*/
unsigned long end_pfn;
/*
* end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
* The direct mapping extends to max_pfn_mapped, so that we can directly access
* apertures, ACPI and other tables without having to play with fixmaps.
*/
unsigned long max_pfn_mapped;
/*
* Last pfn which the user wants to use.
*/
static unsigned long __initdata end_user_pfn = MAXMEM>>PAGE_SHIFT;
/*
* Find the highest page frame number we have available
*/
unsigned long __init e820_end_of_ram(void)
{
unsigned long last_pfn;
last_pfn = find_max_pfn_with_active_regions();
if (last_pfn > max_pfn_mapped)
max_pfn_mapped = last_pfn;
if (max_pfn_mapped > MAXMEM>>PAGE_SHIFT)
max_pfn_mapped = MAXMEM>>PAGE_SHIFT;
if (last_pfn > end_user_pfn)
last_pfn = end_user_pfn;
if (last_pfn > max_pfn_mapped)
last_pfn = max_pfn_mapped;
printk(KERN_INFO "max_pfn_mapped = %lu\n", max_pfn_mapped);
return last_pfn;
}
/*
* Mark e820 reserved areas as busy for the resource manager.
*/
void __init e820_reserve_resources(void)
{
int i;
struct resource *res;
res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
for (i = 0; i < e820.nr_map; i++) {
switch (e820.map[i].type) {
case E820_RAM: res->name = "System RAM"; break;
case E820_ACPI: res->name = "ACPI Tables"; break;
case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
default: res->name = "reserved";
}
res->start = e820.map[i].addr;
res->end = res->start + e820.map[i].size - 1;
res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
insert_resource(&iomem_resource, res);
res++;
}
}
/*
* Finds an active region in the address range from start_pfn to last_pfn and
* returns its range in ei_startpfn and ei_endpfn for the e820 entry.
*/
static int __init e820_find_active_region(const struct e820entry *ei,
unsigned long start_pfn,
unsigned long last_pfn,
unsigned long *ei_startpfn,
unsigned long *ei_endpfn)
{
*ei_startpfn = round_up(ei->addr, PAGE_SIZE) >> PAGE_SHIFT;
*ei_endpfn = round_down(ei->addr + ei->size, PAGE_SIZE) >> PAGE_SHIFT;
/* Skip map entries smaller than a page */
if (*ei_startpfn >= *ei_endpfn)
return 0;
/* Check if max_pfn_mapped should be updated */
if (ei->type != E820_RAM && *ei_endpfn > max_pfn_mapped)
max_pfn_mapped = *ei_endpfn;
/* Skip if map is outside the node */
if (ei->type != E820_RAM || *ei_endpfn <= start_pfn ||
*ei_startpfn >= last_pfn)
return 0;
/* Check for overlaps */
if (*ei_startpfn < start_pfn)
*ei_startpfn = start_pfn;
if (*ei_endpfn > last_pfn)
*ei_endpfn = last_pfn;
/* Obey end_user_pfn to save on memmap */
if (*ei_startpfn >= end_user_pfn)
return 0;
if (*ei_endpfn > end_user_pfn)
*ei_endpfn = end_user_pfn;
return 1;
}
/* Walk the e820 map and register active regions within a node */
void __init
e820_register_active_regions(int nid, unsigned long start_pfn,
unsigned long last_pfn)
{
unsigned long ei_startpfn;
unsigned long ei_endpfn;
int i;
for (i = 0; i < e820.nr_map; i++)
if (e820_find_active_region(&e820.map[i],
start_pfn, last_pfn,
&ei_startpfn, &ei_endpfn))
add_active_range(nid, ei_startpfn, ei_endpfn);
}
/*
* Find the hole size (in bytes) in the memory range.
* @start: starting address of the memory range to scan
* @end: ending address of the memory range to scan
*/
unsigned long __init e820_hole_size(unsigned long start, unsigned long end)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long last_pfn = end >> PAGE_SHIFT;
unsigned long ei_startpfn, ei_endpfn, ram = 0;
int i;
for (i = 0; i < e820.nr_map; i++) {
if (e820_find_active_region(&e820.map[i],
start_pfn, last_pfn,
&ei_startpfn, &ei_endpfn))
ram += ei_endpfn - ei_startpfn;
}
return end - start - (ram << PAGE_SHIFT);
}
static void early_panic(char *msg)
{
early_printk(msg);
panic(msg);
}
/* We're not void only for x86 32-bit compat */
char *__init machine_specific_memory_setup(void)
{
char *who = "BIOS-e820";
int new_nr;
/*
* Try to copy the BIOS-supplied E820-map.
*
* Otherwise fake a memory map; one section from 0k->640k,
* the next section from 1mb->appropriate_mem_k
*/
new_nr = boot_params.e820_entries;
sanitize_e820_map(boot_params.e820_map,
ARRAY_SIZE(boot_params.e820_map),
&new_nr);
boot_params.e820_entries = new_nr;
if (copy_e820_map(boot_params.e820_map, boot_params.e820_entries) < 0)
early_panic("Cannot find a valid memory map");
printk(KERN_INFO "BIOS-provided physical RAM map:\n");
e820_print_map(who);
/* In case someone cares... */
return who;
}
static int __init parse_memopt(char *p)
{
if (!p)
return -EINVAL;
end_user_pfn = memparse(p, &p);
end_user_pfn >>= PAGE_SHIFT;
return 0;
}
early_param("mem", parse_memopt);
static int userdef __initdata;
static int __init parse_memmap_opt(char *p)
{
char *oldp;
unsigned long long start_at, mem_size;
if (!strcmp(p, "exactmap")) {
#ifdef CONFIG_CRASH_DUMP
/*
* If we are doing a crash dump, we still need to know
* the real mem size before original memory map is
* reset.
*/
e820_register_active_regions(0, 0, -1UL);
saved_max_pfn = e820_end_of_ram();
remove_all_active_ranges();
#endif
max_pfn_mapped = 0;
e820.nr_map = 0;
userdef = 1;
return 0;
}
oldp = p;
mem_size = memparse(p, &p);
if (p == oldp)
return -EINVAL;
userdef = 1;
if (*p == '@') {
start_at = memparse(p+1, &p);
add_memory_region(start_at, mem_size, E820_RAM);
} else if (*p == '#') {
start_at = memparse(p+1, &p);
add_memory_region(start_at, mem_size, E820_ACPI);
} else if (*p == '$') {
start_at = memparse(p+1, &p);
add_memory_region(start_at, mem_size, E820_RESERVED);
} else {
end_user_pfn = (mem_size >> PAGE_SHIFT);
}
return *p == '\0' ? 0 : -EINVAL;
}
early_param("memmap", parse_memmap_opt);
void __init finish_e820_parsing(void)
{
if (userdef) {
int nr = e820.nr_map;
if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
early_panic("Invalid user supplied memory map");
e820.nr_map = nr;
printk(KERN_INFO "user-defined physical RAM map:\n");
e820_print_map("user");
}
}
int __init arch_get_ram_range(int slot, u64 *addr, u64 *size)
{
int i;
if (slot < 0 || slot >= e820.nr_map)
return -1;
for (i = slot; i < e820.nr_map; i++) {
if (e820.map[i].type != E820_RAM)
continue;
break;
}
if (i == e820.nr_map || e820.map[i].addr > (max_pfn << PAGE_SHIFT))
return -1;
*addr = e820.map[i].addr;
*size = min_t(u64, e820.map[i].size + e820.map[i].addr,
max_pfn << PAGE_SHIFT) - *addr;
return i + 1;
}
