kexec: allow architectures to override boot mapping
authorRussell King <rmk+kernel@arm.linux.org.uk>
Tue, 2 Aug 2016 21:06:04 +0000 (14:06 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 2 Aug 2016 23:35:27 +0000 (19:35 -0400)
commit43546d8669d62d75fa69ca9a45d2f586665f56bd
tree3546ef2ae7ba4746671fef7bbfb8b1b3072c100a
parentdae28018f56645b61f5beb84d5831346d3c5e457
kexec: allow architectures to override boot mapping

kexec physical addresses are the boot-time view of the system.  For
certain ARM systems (such as Keystone 2), the boot view of the system
does not match the kernel's view of the system: the boot view uses a
special alias in the lower 4GB of the physical address space.

To cater for these kinds of setups, we need to translate between the
boot view physical addresses and the normal kernel view physical
addresses.  This patch extracts the current transation points into
linux/kexec.h, and allows an architecture to override the functions.

Due to the translations required, we unfortunately end up with six
translation functions, which are reduced down to four that the
architecture can override.

[akpm@linux-foundation.org: kexec.h needs asm/io.h for phys_to_virt()]
Link: http://lkml.kernel.org/r/E1b8koP-0004HZ-Vf@rmk-PC.armlinux.org.uk
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/kexec.h
kernel/kexec.c
kernel/kexec_core.c