From 966fab00b0e19e0db3cb11d81bda5d0940176d5e Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 2 Aug 2016 14:05:51 -0700 Subject: ARM: kexec: advertise location of bootable RAM Advertise the location of bootable RAM to kexec-tools. kexec needs to know where it can place the kernel in RAM, and so be executable when the system needs to jump into it. Advertise these areas in /proc/iomem with a "System RAM (boot alias)" tag. Link: http://lkml.kernel.org/r/E1b8ko4-0004HA-GF@rmk-PC.armlinux.org.uk Signed-off-by: Russell King Reviewed-by: Pratyush Anand Cc: Baoquan He Cc: Keerthy Cc: Vitaly Andrianov Cc: Eric Biederman Cc: Dave Young Cc: Vivek Goyal Cc: Simon Horman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/kernel/setup.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel/setup.c') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 6c8c888c1152..df7f2a75e769 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -848,10 +848,29 @@ static void __init request_standard_resources(const struct machine_desc *mdesc) kernel_data.end = virt_to_phys(_end - 1); for_each_memblock(memory, region) { + phys_addr_t start = __pfn_to_phys(memblock_region_memory_base_pfn(region)); + phys_addr_t end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; + unsigned long boot_alias_start; + + /* + * Some systems have a special memory alias which is only + * used for booting. We need to advertise this region to + * kexec-tools so they know where bootable RAM is located. + */ + boot_alias_start = phys_to_idmap(start); + if (arm_has_idmap_alias() && boot_alias_start != IDMAP_INVALID_ADDR) { + res = memblock_virt_alloc(sizeof(*res), 0); + res->name = "System RAM (boot alias)"; + res->start = boot_alias_start; + res->end = phys_to_idmap(end); + res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; + request_resource(&iomem_resource, res); + } + res = memblock_virt_alloc(sizeof(*res), 0); res->name = "System RAM"; - res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region)); - res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1; + res->start = start; + res->end = end; res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; request_resource(&iomem_resource, res); -- cgit v1.2.3