Modern GCC can generate code which makes use of the CPU's native
unaligned memory access capabilities.  This is useful for the C
decompressor implementations used for unpacking compressed kernels.

This patch disables alignment faults and enables the v6 unaligned
access model on CPUs which support these features (i.e., v6 and
later), allowing full unaligned access support for C code in the
decompressor.

The decompressor C code must not be built to assume that unaligned
access works if support for v5 or older platforms is included in
the kernel.

For correct code generation, C decompressor code must always use
the get_unaligned and put_unaligned accessors when dealing with
unaligned pointers, regardless of this patch.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/kernel/smp.c

Pull ARM updates from Russell King:
 "This is the first chunk of ARM updates for this merge window.
  Conflicts are expected in two files - asm/timex.h and
  mach-integrator/integrator_cp.c.  Nothing particularly stands out more
  than anything else.

  Most of the growth is down to the opcodes stuff from Dave Martin,
  which is countered by Rob's patches to use more of the asm-generic
  headers on ARM."

(A few more conflicts grew since then, but it all looked fairly trivial)

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits)
  ARM: 7548/1: include linux/sched.h in syscall.h
  ARM: 7541/1: Add ARM ERRATA 775420 workaround
  ARM: ensure vm_struct has its phys_addr member filled in
  ARM: 7540/1: kexec: Check segment memory addresses
  ARM: 7539/1: kexec: scan for dtb magic in segments
  ARM: 7538/1: delay: add registration mechanism for delay timer sources
  ARM: 7536/1: smp: Formalize an IPI for wakeup
  ARM: 7525/1: ptrace: use updated syscall number for syscall auditing
  ARM: 7524/1: support syscall tracing
  ARM: 7519/1: integrator: convert platform devices to Device Tree
  ARM: 7518/1: integrator: convert AMBA devices to device tree
  ARM: 7517/1: integrator: initial device tree support
  ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ
  ARM: 7515/1: integrator: check PL010 base address from resource
  ARM: 7514/1: integrator: call common init function from machine
  ARM: 7522/1: arch_timers: register a time/cycle counter
  ARM: 7523/1: arch_timers: enable the use of the virtual timer
  ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental
  ARM: 7520/1: Build dtb files in all target
  ARM: Fix build warning in arch/arm/mm/alignment.c
  ...

Pull ARM soc multiplatform enablement from Olof Johansson:
 "This is a pretty significant branch.  It's the introduction of the
  first multiplatform support on ARM, and with this (and the later
  branch) merged, it is now possible to build one kernel that contains
  support for highbank, vexpress, mvebu, socfpga, and picoxcell.  More
  platforms will be convered over in the next few releases.

  Two critical last things had to be done for this to be practical and
  possible:
   * Today each platform has its own include directory under
     mach-<mach>/include/mach/*, and traditionally that is where a lot
     of driver/platform shared definitions have gone, such as platform
     data structures.  They now need to move out to a common location
     instead, and this branch moves a large number of those out to
     include/linux/platform_data.
   * Each platform used to list the device trees to compile for its
     boards in mach-<mach>/Makefile.boot.

  Both of the above changes will mean that there are some merge
  conflicts to come (and some to resolve here).  It's a one-time move
  and once it settles in, we should be good for quite a while.  Sorry
  for the overhead."

Fix conflicts as per Olof.

* tag 'multiplatform' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (51 commits)
  ARM: add v7 multi-platform defconfig
  ARM: msm: Move core.h contents into common.h
  ARM: highbank: call highbank_pm_init from .init_machine
  ARM: dtb: move all dtb targets to common Makefile
  ARM: spear: move platform_data definitions
  ARM: samsung: move platform_data definitions
  ARM: orion: move platform_data definitions
  ARM: vexpress: convert to multi-platform
  ARM: initial multiplatform support
  ARM: mvebu: move armada-370-xp.h in mach dir
  ARM: vexpress: remove dependency on mach/* headers
  ARM: picoxcell: remove dependency on mach/* headers
  ARM: move all dtb targets out of Makefile.boot
  ARM: picoxcell: move debug macros to include/debug
  ARM: socfpga: move debug macros to include/debug
  ARM: mvebu: move debug macros to include/debug
  ARM: vexpress: move debug macros to include/debug
  ARM: highbank: move debug macros to include/debug
  ARM: move debug macros to common location
  ARM: make mach/gpio.h headers optional
  ...

Enable initial ARM multi-platform support for highbank, mvebu,
socfpga, picoxcell, and vexpress.

Multi-platform support is dependent on mach/gpio.h removal and
restructuring of DEBUG_LL and dtb build rules included in this branch.

This has been built for all defconfigs, and booted on highbank with
all 5 platforms enabled.

By Rob Herring (18) and Arnd Bergmann (1)
via Rob Herring
* tag 'multi-platform-for-3.7' of git://sources.calxeda.com/kernel/linux:
  ARM: vexpress: convert to multi-platform
  ARM: initial multiplatform support
  ARM: mvebu: move armada-370-xp.h in mach dir
  ARM: vexpress: remove dependency on mach/* headers
  ARM: picoxcell: remove dependency on mach/* headers
  ARM: move all dtb targets out of Makefile.boot
  ARM: picoxcell: move debug macros to include/debug
  ARM: socfpga: move debug macros to include/debug
  ARM: mvebu: move debug macros to include/debug
  ARM: vexpress: move debug macros to include/debug
  ARM: highbank: move debug macros to include/debug
  ARM: move debug macros to common location
  ARM: make mach/gpio.h headers optional
  ARM: orion: move custom gpio functions to orion-gpio.h
  ARM: shmobile: move custom gpio functions to sh-gpio.h
  ARM: pxa: use gpio_to_irq for sharppm_sl
  net: pxaficp_ir: add irq resources
  usb: pxa27x_udc: remove IRQ_USB define
  staging: ste_rmi4: remove gpio.h include

Conflicts due to addition of bcm2835 and removal of pnx4008 in:
	arch/arm/Kconfig
	arch/arm/Makefile

Conflicts due to new dtb targets, moved to arch/arm/boot/dts/Makefile in:
	arch/arm/mach-imx/Makefile.boot
	arch/arm/mach-mxs/Makefile.boot
	arch/arm/mach-tegra/Makefile.boot

Signed-off-by: Olof Johansson <olof@lixom.net>

The zImage loader needs to turn on the MMU in order to take
advantage of caching while decompressing the zImage.  Running this
in hyp mode would require the LPAE pagetable format to be
supported; to avoid this complexity, this patch switches out of hyp
mode, and returns back to hyp mode just before booting the kernel.

This implementation assumes that the Hyp mode view of memory and the
PL1 view of memory are coherent, providing that the MMU and caches
are off in both, as required by the boot protocol.  The zImage
decompression code must drain the write buffer on completion anyway, and
entry into Hyp mode should flush any prefetch buffer, avoiding hazards
associated with local write buffers and the pipeline.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

This patch zeroes the SCTLR.TRE bit prior to setting the mapping as
cacheable for ARMv7 cores in the decompressor, ensuring that the
memory region attributes are obtained from the C and B bits, not from
the page tables.

Cc: Nicolas Pitre <nico@fluxnic.net>
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>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This lets us build a multiplatform kernel for experimental purposes.
However, it will not be useful for any real work, because it relies
on a number of useful things to be disabled for now:

* SMP support must be turned off because of conflicting symbols.
  Marc Zyngier has proposed a solution by adding a new SOC
  operations structure to hold indirect function pointers
  for these, but that work is currently stalled

* We turn on SPARSE_IRQ unconditionally, which is not supported
  on most platforms. Each of them is currently in a different
  state, but most are being worked on.

* A common clock framework is in place since v3.4 but not yet
  being used. Work on this is on its way.

* DEBUG_LL for early debugging is currently disabled.

* THUMB2_KERNEL does not work with allyesconfig because the
  kernel gets too big

[Rob Herring]: Rebased to not be dependent on the mass mach header rename.
As a result, omap2plus, imx, mxs and ux500 are not converted. Highbank,
picoxcell, mvebu, and socfpga are converted.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Cc: Dinh Nguyen <dinguyen@altera.com>