linux.git/arch/powerpc/kernel/prom_init_check.sh, branch v3.2

powerpc/powernv: Get kernel command line accross OPAL takeover

2011-09-20T06:09:48+00:00

We stash it in boot_command_line which isn't in BSS and so won't
be overwritten. We then use that as a default cmd_line before
we walk the device-tree.

Signed-off-by: Benjamin Herrenschmidt

powerpc/powernv: Add OPAL takeover from PowerVM

2011-09-20T06:09:47+00:00

On machines supporting the OPAL firmware version 1, the system
is initially booted under pHyp. We then use a special hypercall
to verify if OPAL is available and if it is, we then trigger
a "takeover" which disables pHyp and loads the OPAL runtime
firmware, giving control to the kernel in hypervisor mode.

This patch add the necessary code to detect that the OPAL takeover
capability is present when running under PowerVM (aka pHyp) and
perform said takeover to get hypervisor control of the processor.

To perform the takeover, we must first use RTAS (within Open
Firmware runtime environment) to start all processors & threads,
in order to give control to OPAL on all of them. We then call
the takeover hypercall on everybody, OPAL will re-enter the kernel
main entry point passing it a flat device-tree.

Signed-off-by: Benjamin Herrenschmidt

powerpc: Fix compile errors in prom_init_check for gcc 4.5

2010-07-08T08:11:39+00:00

Just whitelist these extra compiler generated symbols.
Fixes these errors:

Error: External symbol '_restgpr0_14' referenced from prom_init.c
Error: External symbol '_restgpr0_20' referenced from prom_init.c
Error: External symbol '_restgpr0_22' referenced from prom_init.c
Error: External symbol '_restgpr0_24' referenced from prom_init.c
Error: External symbol '_restgpr0_25' referenced from prom_init.c
Error: External symbol '_restgpr0_26' referenced from prom_init.c
Error: External symbol '_restgpr0_27' referenced from prom_init.c
Error: External symbol '_restgpr0_28' referenced from prom_init.c
Error: External symbol '_restgpr0_29' referenced from prom_init.c
Error: External symbol '_restgpr0_31' referenced from prom_init.c
Error: External symbol '_savegpr0_14' referenced from prom_init.c
Error: External symbol '_savegpr0_20' referenced from prom_init.c
Error: External symbol '_savegpr0_22' referenced from prom_init.c
Error: External symbol '_savegpr0_24' referenced from prom_init.c
Error: External symbol '_savegpr0_25' referenced from prom_init.c
Error: External symbol '_savegpr0_26' referenced from prom_init.c
Error: External symbol '_savegpr0_27' referenced from prom_init.c
Error: External symbol '_savegpr0_28' referenced from prom_init.c
Error: External symbol '_savegpr0_29' referenced from prom_init.c
Error: External symbol '_savegpr0_31' referenced from prom_init.c

Signed-off-by: Stephen Rothwell 
Acked-by: Segher Boessenkool 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Print linux_banner in prom_init

2009-03-11T06:11:33+00:00

So at least you can see what kernel you're booting if you die
before the kernel prints it mid-way through start_kernel().

Signed-off-by: Michael Ellerman 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Fix build issue with CONFIG_RELOCATABLE=y

2008-10-21T04:17:49+00:00

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 
Signed-off-by: Benjamin Herrenschmidt

[POWERPC] Fix -Os kernel builds with newer gcc versions

2008-06-16T05:00:54+00:00

GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html

This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE.  To fix
this we add the use the save/restore code from gcc and simplified it down
for our needs (integer only).

Additionally, we have to link this code into each module.  The other
solution was to add EXPORT_SYMBOL() which meant going through the
trampoline which seemed nonsensical for these out-of-line routines.

Finally, we add some checks to prom_init_check.sh to ignore the
out-of-line save/restore functions.

Signed-off-by: Kumar Gala 
Signed-off-by: Paul Mackerras

[POWERPC] Add kernstart_addr to list of allowed symbols in prom_init

2008-05-23T06:15:35+00:00

Since commit "85xx: Add support for relocatable kernel (and
booting at non-zero)" (37dd2badcfcec35f5e21a0926968d77a404f03c3),
PHYSICAL_START is #defined as kernstart_addr if RELOCATABLE
and FLATMEM is enabled.

PHYSICAL_START is used in prom_init.c and so kernstart_addr
needs to be added to the list of allowed symbols that
prom_init.c can access.

Signed-off-by: Michael Ellerman 
Acked-by: Kumar Gala 
Signed-off-by: Paul Mackerras

[POWERPC] Discourage people from fiddling with kernel data from prom_init

2008-04-24T10:58:03+00:00

As BenH said the other day, it is an "accident" that prom_init.o is
linked with the rest of the kernel.  The truth is a little more
subtle, prom_init isn't truly bootloader, it does access kernel data
in a few places.

What we can do is discourage people from adding new code that accesses
data outside of prom_init.  And hence this patch; from the script:

 # This script checks prom_init.o to see what external symbols it
 # is using, if it finds symbols not in the whitelist it returns
 # an error. The point of this is to discourage people from
 # intentionally or accidentally adding new code to prom_init.c
 # which has side effects on other parts of the kernel.

Signed-off-by: Michael Ellerman 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras