From 0962e8004e97409072bb6caee7b3ba948a5fb93a Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Wed, 24 Apr 2013 14:26:30 +0800 Subject: 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/prom.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'arch/powerpc/kernel/prom.c') 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)) -- cgit v1.2.3 From c039e3a8ddd52139d0f81711ecd757772f868b22 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 2 Jul 2013 08:13:52 +1000 Subject: powerpc: Handle both new style and old style reserve maps When Jeremy introduced the new device-tree based reserve map, he made the code in early_reserve_mem_dt() bail out if it found one, thus not reserving the initrd nor processing the old style map. I hit problems with variants of kexec that didn't put the initrd in the new style map either. While these could/will be fixed, I believe we should be safe here and rather reserve more than not enough. We could have a firmware passing stuff via the new style map, and in the middle, a kexec that knows nothing about it and adding other things to the old style map. I don't see a big issue with processing both and reserving everything that needs to be. memblock_reserve() supports overlaps fine these days. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/prom.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-) (limited to 'arch/powerpc/kernel/prom.c') diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 9c753bc9885d..eb23ac92abb9 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -559,7 +559,7 @@ void __init early_init_dt_setup_initrd_arch(unsigned long start, } #endif -static bool __init early_reserve_mem_dt(void) +static void __init early_reserve_mem_dt(void) { unsigned long i, len, dt_root; const __be32 *prop; @@ -569,7 +569,9 @@ static bool __init early_reserve_mem_dt(void) prop = of_get_flat_dt_prop(dt_root, "reserved-ranges", &len); if (!prop) - return false; + return; + + DBG("Found new-style reserved-ranges\n"); /* Each reserved range is an (address,size) pair, 2 cells each, * totalling 4 cells per range. */ @@ -579,11 +581,11 @@ static bool __init early_reserve_mem_dt(void) base = of_read_number(prop + (i * 4) + 0, 2); size = of_read_number(prop + (i * 4) + 2, 2); - if (size) + if (size) { + DBG("reserving: %llx -> %llx\n", base, size); memblock_reserve(base, size); + } } - - return true; } static void __init early_reserve_mem(void) @@ -601,20 +603,16 @@ 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; + /* Look for the new "reserved-regions" property in the DT */ + early_reserve_mem_dt(); #ifdef CONFIG_BLK_DEV_INITRD - /* then reserve the initrd, if any */ - if (initrd_start && (initrd_end > initrd_start)) + /* Then reserve the initrd, if any */ + if (initrd_start && (initrd_end > initrd_start)) { memblock_reserve(_ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE), _ALIGN_UP(initrd_end, PAGE_SIZE) - _ALIGN_DOWN(initrd_start, PAGE_SIZE)); + } #endif /* CONFIG_BLK_DEV_INITRD */ #ifdef CONFIG_PPC32 @@ -626,6 +624,8 @@ static void __init early_reserve_mem(void) u32 base_32, size_32; u32 *reserve_map_32 = (u32 *)reserve_map; + DBG("Found old 32-bit reserve map\n"); + while (1) { base_32 = *(reserve_map_32++); size_32 = *(reserve_map_32++); @@ -640,6 +640,9 @@ static void __init early_reserve_mem(void) return; } #endif + DBG("Processing reserve map\n"); + + /* Handle the reserve map in the fdt blob if it exists */ while (1) { base = *(reserve_map++); size = *(reserve_map++); -- cgit v1.2.3