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author | John Crispin <blogic@openwrt.org> | 2013-04-13 13:15:47 +0200 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2013-05-08 01:19:11 +0200 |
commit | 4d9f77d2526840fc2b3d4dcaedfd2f633a6d5426 (patch) | |
tree | 7efbfc22a32c23dc886855b325b88e7356a4f355 /arch/mips | |
parent | DT: MIPS: ralink: add MT7620A dts files (diff) | |
download | linux-4d9f77d2526840fc2b3d4dcaedfd2f633a6d5426.tar.xz linux-4d9f77d2526840fc2b3d4dcaedfd2f633a6d5426.zip |
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 <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/5178/
Diffstat (limited to 'arch/mips')
-rw-r--r-- | arch/mips/include/asm/bootinfo.h | 1 | ||||
-rw-r--r-- | arch/mips/kernel/setup.c | 22 |
2 files changed, 23 insertions, 0 deletions
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 <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; |