There are two issues when we enable CONFIG_RELOCATABLE. The first is due
to the fact that phys_addr_t is now defined in linux/types.h. The second
is due to the fact that the DMA code changes expose memstart_addr to
prom_init.c
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Today's linux-next build (powerpc allyesconfig) failed like this:
In file included from arch/powerpc/include/asm/mmu-hash64.h:17,
from arch/powerpc/include/asm/mmu.h:8,
from arch/powerpc/include/asm/pgtable.h:8,
from arch/powerpc/mm/slb.c:20:
arch/powerpc/include/asm/page.h:76: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'memstart_addr'
arch/powerpc/include/asm/page.h:77: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'kernstart_addr'
Caused by commit 600715dcdf ("generic: add
phys_addr_t for holding physical addresses") from the tip-core tree.
This only fails if CONFIG_RELOCATABLE is set.
So include that instead of asm/types.h in asm/page.h for
the CONFIG_RELOCATABLE case.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: ppc-dev <linuxppc-dev@ozlabs.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This implements CONFIG_RELOCATABLE for 64-bit by making the kernel as
a position-independent executable (PIE) when it is set. This involves
processing the dynamic relocations in the image in the early stages of
booting, even if the kernel is being run at the address it is linked at,
since the linker does not necessarily fill in words in the image for
which there are dynamic relocations. (In fact the linker does fill in
such words for 64-bit executables, though not for 32-bit executables,
so in principle we could avoid calling relocate() entirely when we're
running a 64-bit kernel at the linked address.)
The dynamic relocations are processed by a new function relocate(addr),
where the addr parameter is the virtual address where the image will be
run. In fact we call it twice; once before calling prom_init, and again
when starting the main kernel. This means that reloc_offset() returns
0 in prom_init (since it has been relocated to the address it is running
at), which necessitated a few adjustments.
This also changes __va and __pa to use an equivalent definition that is
simpler. With the relocatable kernel, PAGE_OFFSET and MEMORY_START are
constants (for 64-bit) whereas PHYSICAL_START is a variable (and
KERNELBASE ideally should be too, but isn't yet).
With this, relocatable kernels still copy themselves down to physical
address 0 and run there.
Signed-off-by: Paul Mackerras <paulus@samba.org>
from include/asm-powerpc. This is the result of a
mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm
Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Benjamin Herrenschmidt