Commit 4d9f77d2 authored by John Crispin's avatar John Crispin Committed by Ralf Baechle
Browse files

MIPS: add detect_memory_region() 



Add a generic way of detecting the available RAM. This function is based on the
implementation already used by ath79.

Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/5178/
parent 9d50094d

arch/mips/include/asm/bootinfo.h

+1 −0
Original line number Diff line number Diff line
@@ -104,6 +104,7 @@ struct boot_mem_map { 
extern struct boot_mem_map boot_mem_map;



extern void add_memory_region(phys_t start, phys_t size, long type);

extern void detect_memory_region(phys_t start, phys_t sz_min,  phys_t sz_max);



extern void prom_init(void);

extern void prom_free_prom_memory(void);

arch/mips/kernel/setup.c

+22 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ 
#include <linux/pfn.h>

#include <linux/debugfs.h>

#include <linux/kexec.h>

#include <linux/sizes.h>



#include <asm/addrspace.h>

#include <asm/bootinfo.h>
@@ -77,6 +78,8 @@ EXPORT_SYMBOL(mips_io_port_base); 
static struct resource code_resource = { .name = "Kernel code", };

static struct resource data_resource = { .name = "Kernel data", };



static void *detect_magic __initdata = detect_memory_region;



void __init add_memory_region(phys_t start, phys_t size, long type)

{

	int x = boot_mem_map.nr_map;
@@ -122,6 +125,25 @@ void __init add_memory_region(phys_t start, phys_t size, long type) 
	boot_mem_map.nr_map++;

}



void __init detect_memory_region(phys_t start, phys_t sz_min, phys_t sz_max)

{

	void *dm = &detect_magic;

	phys_t size;



	for (size = sz_min; size < sz_max; size <<= 1) {

		if (!memcmp(dm, dm + size, sizeof(detect_magic)))

			break;

	}



	pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",

		((unsigned long long) size) / SZ_1M,

		(unsigned long long) start,

		((unsigned long long) sz_min) / SZ_1M,

		((unsigned long long) sz_max) / SZ_1M);



	add_memory_region(start, size, BOOT_MEM_RAM);

}



static void __init print_memory_map(void)

{

	int i;