diff options
| author | Matthew Leach <matthew.leach@arm.com> | 2012-09-21 18:56:02 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-09-26 22:58:36 +0100 |
| commit | 4cabd1d9625c7d88acd143f4021fbef75394f154 (patch) | |
| tree | 3c232277c6bd94c7c4f17714de2104652735bdfb /arch/arm/kernel | |
| parent | 559a593905e583fca23229b916c016e5211c6766 (diff) | |
ARM: 7539/1: kexec: scan for dtb magic in segments
This patch allows a dtb to be passed to a new kernel using the kexec
mechinism.
When loading segments from userspace, scan each segment's first four
bytes for the dtb magic. If this is found set the kexec_boot_atags
parameter to the relocate_kernel code to the phyical address of this
segment.
Reviewed-by: Simon Horman <horms@verge.net.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/machine_kexec.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index dfcdb9f7c126..dee34efca748 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -9,6 +9,7 @@ #include <linux/io.h> #include <linux/irq.h> #include <asm/pgtable.h> +#include <linux/of_fdt.h> #include <asm/pgalloc.h> #include <asm/mmu_context.h> #include <asm/cacheflush.h> @@ -32,6 +33,24 @@ static atomic_t waiting_for_crash_ipi; int machine_kexec_prepare(struct kimage *image) { + struct kexec_segment *current_segment; + __be32 header; + int i, err; + + /* + * No segment at default ATAGs address. try to locate + * a dtb using magic. + */ + for (i = 0; i < image->nr_segments; i++) { + current_segment = &image->segment[i]; + + err = get_user(header, (__be32*)current_segment->buf); + if (err) + return err; + + if (be32_to_cpu(header) == OF_DT_HEADER) + kexec_boot_atags = current_segment->mem; + } return 0; } @@ -122,7 +141,9 @@ void machine_kexec(struct kimage *image) kexec_start_address = image->start; kexec_indirection_page = page_list; kexec_mach_type = machine_arch_type; - kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET; + if (!kexec_boot_atags) + kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET; + /* copy our kernel relocation code to the control code page */ memcpy(reboot_code_buffer, |