diff options
| author | Jeremy Kerr <jk@ozlabs.org> | 2013-04-24 14:26:30 +0800 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-06-20 16:55:11 +1000 |
| commit | 0962e8004e97409072bb6caee7b3ba948a5fb93a (patch) | |
| tree | 9fdf0269b2cb7a2ce2c1c36da33d1663ba4dce8f /arch | |
| parent | d5d8ec895ca599fbde43efe3a2f9714315e3d298 (diff) | |
powerpc/prom: Scan reserved-ranges node for memory reservations
Based on benh's proposal at
https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-September/101237.html,
this change provides support for reserving memory from the
reserved-ranges node at the root of the device tree.
We just call memblock_reserve on these ranges for now.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/prom.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 8b6f7a99cce2..9c753bc9885d 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -559,6 +559,33 @@ void __init early_init_dt_setup_initrd_arch(unsigned long start, } #endif +static bool __init early_reserve_mem_dt(void) +{ + unsigned long i, len, dt_root; + const __be32 *prop; + + dt_root = of_get_flat_dt_root(); + + prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len); + + if (!prop) + return false; + + /* Each reserved range is an (address,size) pair, 2 cells each, + * totalling 4 cells per range. */ + for (i = 0; i < len / (sizeof(*prop) * 4); i++) { + u64 base, size; + + base = of_read_number(prop + (i * 4) + 0, 2); + size = of_read_number(prop + (i * 4) + 2, 2); + + if (size) + memblock_reserve(base, size); + } + + return true; +} + static void __init early_reserve_mem(void) { u64 base, size; @@ -574,6 +601,14 @@ static void __init early_reserve_mem(void) self_size = initial_boot_params->totalsize; memblock_reserve(self_base, self_size); + /* + * Try looking for reserved-regions property in the DT first; if + * it's present, it'll contain all of the necessary reservation + * info + */ + if (early_reserve_mem_dt()) + return; + #ifdef CONFIG_BLK_DEV_INITRD /* then reserve the initrd, if any */ if (initrd_start && (initrd_end > initrd_start)) |