treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_56.RULE (part 1)

Based on the normalized pattern:

this file is licensed under the terms of the gnu general public
license version 2 this program is licensed as is without any warranty
of any kind whether express or implied

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Reviewed-by: Allison Randal <allison@lohutok.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arm/mach-mvebu: remove legacy __cpuinit sections that crept in

We removed __cpuinit support (leaving no-op stubs) quite some time
ago. However these ones crept back in as of commit 1ee89e2231a1b04dc3476
("ARM: mvebu: add SMP support for Armada 375 and Armada 38x")

Since we want to clobber the stubs soon, get this removed now.
Note that there would normally be a corresponding removal of
a ".previous" directive for each __CPUINIT in asm files, but in
this case it appears that this single function file was never
paired off with one.

Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

ARM: v7 setup function should invalidate L1 cache

All ARMv5 and older CPUs invalidate their caches in the early assembly
setup function, prior to enabling the MMU. This is because the L1
cache should not contain any data relevant to the execution of the
kernel at this point; all data should have been flushed out to memory.

This requirement should also be true for ARMv6 and ARMv7 CPUs - indeed,
these typically do not search their caches when caching is disabled (as
it needs to be when the MMU is disabled) so this change should be safe.

ARMv7 allows there to be CPUs which search their caches while caching is
disabled, and it's permitted that the cache is uninitialised at boot;
for these, the architecture reference manual requires that an
implementation specific code sequence is used immediately after reset
to ensure that the cache is placed into a sane state. Such
functionality is definitely outside the remit of the Linux kernel, and
must be done by the SoC's firmware before _any_ CPU gets to the Linux
kernel.

Changing the data cache clean+invalidate to a mere invalidate allows us
to get rid of a lot of platform specific hacks around this issue for
their secondary CPU bringup paths - some of which were buggy.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: mvebu: Fix the secondary startup for Cortex A9 SoC

During the secondary startup the SCU was assumed to be in normal
mode. It is not always the case, and especially after a kexec. This
commit adds the needed sequence to put the SCU in normal mode.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1414669184-16785-4-git-send-email-gregory.clement@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

ARM: mvebu: use the common function for Armada 375 SMP workaround

Use the common function mvebu_setup_boot_addr_wa() introduced in the
commit "ARM: mvebu: Add a common function for the boot address work
around" instead of the dedicated version for Armada 375.

This commit also moves the workaround in the system-controller
module. Indeed the workaround on 375 is really related to setting the
boot address which is done by the system controller.

As a bonus we no longer use an harcoded value to access the register
storing the boot address.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1406120453-29291-5-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+

ARMv6 and greater introduced a new instruction ("bx") which can be used
to return from function calls. Recent CPUs perform better when the
"bx lr" instruction is used rather than the "mov pc, lr" instruction,
and this sequence is strongly recommended to be used by the ARM
architecture manual (section A.4.1.1).

We provide a new macro "ret" with all its variants for the condition
code which will resolve to the appropriate instruction.

Rather than doing this piecemeal, and miss some instances, change all
the "mov pc" instances to use the new macro, with the exception of
the "movs" instruction and the kprobes code. This allows us to detect
the "mov pc, lr" case and fix it up - and also gives us the possibility
of deploying this for other registers depending on the CPU selection.

Reported-by: Will Deacon <will.deacon@arm.com>
Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S
Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood
Tested-by: Shawn Guo <shawn.guo@freescale.com>
Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385
Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci
Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M
Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

ARM: mvebu: fix SMP boot for Armada 38x and Armada 375 Z1 in big endian

The SMP boot on Armada 38x and Armada 375 Z1 is currently broken in
big-endian configurations, and this commit fixes it for both
platforms.

For Armada 375 Z1, the problem was in the
armada_375_smp_cpu1_enable_code part of the code that gets copied to
the Crypto SRAM as a work-around for an issue of the Z1 stepping. This
piece of code was not switching the CPU core to big-endian, and not
endian-swapping the value read from the Resume Address register (the
value is stored little-endian). Due to the introduction of the
conditional 'rev r1, r1' instruction, the offset between the 'ldr r0,
[pc, #4]' instruction and the value it was looking is different
between LE and BE configurations. To solve this, we instead use one
'adr' instruction followed by one 'ldr'.

For Armada 38x, the problem was simply that the CPU core was not
switched to big endian in the secondary CPU startup function.

This change was tested in LE and BE configurations on Armada 385,
Armada 375 Z1 and Armada 375 A0.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1404228186-21203-1-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

ARM: mvebu: add workaround for SMP support for Armada 375 stepping Z1

Due to internal bootrom issue, CPU[1] initial jump code (four
instructions) should be placed in SRAM memory of the SoC. In order to
achieve this, we have to unmap the BootROM and at some specific
location where the BootROM was place, create a specific MBus window
for the SRAM. This SRAM is initialized with a few instructions of code
that allows to jump into the real secondary CPU boot address.

This workaround will most likely be disabled when newer steppings of
the Armada 375 will be made available, in which case a dynamic test
based on mvebu-soc-id will be added.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-10-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-10-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

ARM: mvebu: add SMP support for Armada 375 and Armada 38x

This commit adds the SMP support for Armada 375 and Armada 38x. It
turns out that the SMP logic for both of these SOCs are fairly
similar, the only differences being:

* A different method to set the secondary CPU boot address

* An Armada 375 specific workaround needed for the early Z1 stepping,
added by the following patch.

Other than that, the patch is fairly straightforward and adds the
usual platsmp and headsmp code, defining the smp_operations structure
that is referenced from the DT_MACHINE structures.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-9-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-9-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>