[PATCH v5 REPOST 0/5] ARM: omap[34]: Thumb-2 compatibility fixes

Dave Martin [off-list ref] writes:

This set of patches, along with some other patches under
discussion on alkml, should enable omap3 and omap4 kernels to be
built with CONFIG_THUMB2_KERNEL.

This patch set builds on recent cleanup done by the omap
maintainers.

At least some of this code definitely works, most features have
been tested successfully.  Further testing, especially of Thumb-2
behaviour, is still welcome.

In particular, I still have no Ack/Tested-by on the following
patches, so it would be great if anyone who has an opportunity
to do a final review / re-test can do so.

 * ARM: omap3: Convert END() to ENDPROC() for correct linkage with CONFIG_THUMB2_KERNEL
 * ARM: omap3: Thumb-2 compatibility for sram34xx.S
 * ARM: omap3: Thumb-2 compatibility for sleep34xx.S

Jean Pihet and I have now done both retention and off-mode testing
of these, so I'll add a Tested-by for the last two for Jean and queue
these for 2.6.39 in my PM queue

  git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git for_2.6.39/pm-misc

If you want to do sanity checking with all the other OMAP PM stuff that
is queued for 2.6.39, feel free to test with my pm-core branch in the
tree above.  This has all OMAP PM related changes that will be queued
for 2.6.39 integrated.

FWIW, I also tested on 3430/n900 (retention and off-mode) and 3630/Zoom3
(retention-only, since the Si rev have has off-mode errata.)

Kevin

Seems to work with CONFIG_SMP_ON_UP and CONFIG_THUMB2_KERNEL
enabled on Beagle xM A2 and Panda A1.

Thanks also to Santosh Shilimkar and Kevin Hilman for their help
with testing so far.


v3:
    * make SMC instruction syntax more consistent
    * remove do_wfi() in favour of the generic wfi() macro

v4:
    * revert to the OMAP-specific do_wfi() implementation, pending
      discussion of how generic macros can/should be provided

v5:
    * use ARM for low-level code in mach-omap2/*34xx.S, for
      correct interoperation with non-Thumb-capable firmware.

I've stripped the Acked/Tested-bys from the major patches to
mach-omap2/*34xx.S, since the reversion to ARM constitutes a
significant change -- I would be grateful if people could re-
test / re-review if they have the chance.

For best future compatibility, I've left the changes which
avoid architecturally deprecated features.


Details below.

Cheers,
Dave


The patches can be found, along with a buildable working tree,
in the following repo:

git://git.linaro.org/people/dmart/linux-2.6-arm.git

 * arm/omap-thumb2: has the patches proposed here
 * arm/omap-thumb2+merged: additionally has some patches cherry-
        picked from other trees which are needed in order for the
        patches on arm/omap-thumb2 to work usefully.
 * dirty/arm/omap-thumb2+merged: buildable test tree, which adds
        2 local patches to work around a toolchain bug.

A working kernel config for this tree is here:
http://people.linaro.org/~dmart/arm_omap-thumb2+v2_config :

  CONFIG_SMP_ON_UP=y
  CONFIG_THUMB2_KERNEL=y
  CONFIG_SERIAL_OMAP=y (to avoid garbage on xM; for Panda use console=ttyS2)

(The config is derived from the linaro omap config and so turns on
loads of modules -- don't feel you have to build them all...)


Cherry-picked patches originated from Russell's devel tree
and Tony Lindgren's omap-testing tree:

http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm.git devel

git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6.git omap-testing

This series also depends on one un-merged patch to generic-ise
the wfi() macro:

git://git.linaro.org/people/dmart/linux-2.6-arm.git arm/wfi-macro


Dave Martin (5):
  ARM: omap4: Provide do_wfi() for Thumb-2
  ARM: omap4: Convert END() to ENDPROC() for correct linkage with
    CONFIG_THUMB2_KERNEL
  ARM: omap3: Remove hand-encoded SMC instructions
  ARM: omap3: Thumb-2 compatibility for sram34xx.S
  ARM: omap3: Thumb-2 compatibility for sleep34xx.S

 arch/arm/mach-omap2/include/mach/omap4-common.h |    4 ++
 arch/arm/mach-omap2/omap-headsmp.S              |    2 +-
 arch/arm/mach-omap2/omap44xx-smc.S              |    8 ++--
 arch/arm/mach-omap2/sleep34xx.S                 |   62 ++++++++++++++++++----
 arch/arm/mach-omap2/sram34xx.S                  |   36 ++++++++++---
 5 files changed, 87 insertions(+), 25 deletions(-)