From 4d9f77d2526840fc2b3d4dcaedfd2f633a6d5426 Mon Sep 17 00:00:00 2001 From: John Crispin Date: Sat, 13 Apr 2013 13:15:47 +0200 Subject: [PATCH] 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: John Crispin Patchwork: http://patchwork.linux-mips.org/patch/5178/ --- arch/mips/include/asm/bootinfo.h | 1 + arch/mips/kernel/setup.c | 22 ++++++++++++++++++++++ 2 files changed, 23 insertions(+) diff --git a/arch/mips/include/asm/bootinfo.h b/arch/mips/include/asm/bootinfo.h index b71dd5b16085..4d2cdea5aa37 100644 --- a/arch/mips/include/asm/bootinfo.h +++ b/arch/mips/include/asm/bootinfo.h @@ -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); diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 4c774d5d5087..c7f90519e58c 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -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; -- 2.39.5