Most of the function related to the PMSU are not specific to the
Armada 370 or Armada XP SoCs. They can also be used for most of the
other mvebu ARMv7 SoCs, and will actually be used to support cpuidle
on Armada 38x.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1406120453-29291-6-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

In the Armada XP SMP support code, we are reading the clock frequency
of the booting CPU, and use that to assign the same frequency to the
other CPUs, and we do this while the clocks are disabled.

However, the CPU clocks are in fact never prepared/enabled, and to
support cpufreq, we now have two code paths to change the frequency of
the CPU clocks in the CPU clock driver: one when the clock is enabled
(dynamic frequency scaling), one when the clock is disabled (adjusting
the CPU frequency before starting the CPU). In order for this to work,
the CPU clocks now have to be prepared and enabled after the initial
synchronization of the clock frequencies is done, so that all future
rate changes of the CPU clocks will trigger a dynamic frequency
scaling transition.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1404920715-19834-2-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

This commit implements CPU hotplug support for the Marvell Armada XP
platform. The CPU hotplug stub functions from hotplug.c are moved into
platsmp.c, as it doesn't make much sense to have a separate file just
for these two functions.

In addition, this commit:

 * Implements the ->cpu_die() function of SMP operations by calling
   armada_370_xp_pmsu_idle_enter() to enter the deep idle state for
   CPUs going offline.

 * Implements a dummy ->cpu_kill() function, simply needed for the
   kernel to know we have CPU hotplug support.

 * The armada_xp_boot_secondary() function makes sure to wake up the
   CPU if waiting in deep idle state by sending an IPI. This is
   because armada_xp_boot_secondary() is now used in two different
   situations: for the initial boot of secondary CPUs (where CPU reset
   deassert is used to wake up CPUs) and for CPU hotplug (where an IPI
   is used to take CPU out of deep idle).

 * At boot time, we exit from the idle state in the
   ->smp_secondary_init() hook.

This commit has been tested using CPU hotplug through sysfs
(/sys/devices/system/cpu/cpuX/online) and using kexec.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1401481098-23326-5-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

set_cpu_coherent() took the SMP group ID as parameter. But this
parameter was never used, and the CPU always uses the SMP group 0. So
we can remove this parameter.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397488214-20685-5-git-send-email-gregory.clement@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

ll_set_cpu_coherent is always used on the current CPU, so instead of
passing the CPU id as argument, ll_set_cpu_coherent() can find it by
itself.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397488214-20685-4-git-send-email-gregory.clement@free-electrons.comAcked-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

This commit adds the CPU_METHOD_OF_DECLARE declaration for the Armada
XP SMP operations. Note that the .smp_ops field of Armada XP
DT_MACHINE structure is kept, in order to ensure we remain compatible
with older Device Trees that do not include the "enable-method"
property for the CPUs.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-3-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The pmsu.c driver contained an armada_xp_boot_cpu() function that sets
the boot address of a secondary CPUs and deasserts the reset. However,
the Armada 375 needs a slightly different logic, so it makes more
sense to move this code into the Armada XP specific platsmp.c.

In order to achieve this, the mvebu_pmsu_set_cpu_boot_addr() function
is exported. It will be needed for both the Armada XP and Armada 38x
SMP implementations.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-2-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Some irqchip initialization must be done on secondary CPUs. On mvebu
platforms, this is currently achieved by having the
arch/arm/mach-mvebu/platsmp.c code directly call into a function
exported by the irqchip driver, which isn't really nice.

This commit changes this by using the same solution as the one used in
the GIC driver: the irqchip driver registers a CPU notifier, which is
used to do the secondary CPU IRQ initialization. This way, the irqchip
driver is completely autonomous, and the function no longer needs to
be exposed from the irqchip driver to the SoC code.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-6-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Instead of having the SoC code in arch/arm/mach-mvebu/platsmp.c do the
set_smp_cross_call() to register the IPI-triggering function, it makes
more sense to do exactly what the GIC driver is doing: let the irqchip
driver do it. This way, it avoids having to expose the
armada_mpic_send_doorbell() function between the irqchip driver and
the SoC code.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1397483648-26611-5-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

This patch fixes conflicting types for 'set_cpu_coherent' and fixes the
following sparse warnings.

arch/arm/mach-mvebu/system-controller.c:42:38:
warning: symbol 'armada_370_xp_system_controller' was not declared. Should it be static?
arch/arm/mach-mvebu/system-controller.c:49:38:
warning: symbol 'orion_system_controller' was not declared. Should it be static?
arch/arm/mach-mvebu/system-controller.c:67:6:
warning: symbol 'mvebu_restart' was not declared. Should it be static?
arch/arm/mach-mvebu/coherency.c:31:15:
warning: symbol 'coherency_phys_base' was not declared. Should it be static?
arch/arm/mach-mvebu/coherency.c:48:5:
warning: symbol 'set_cpu_coherent' was not declared. Should it be static?
arch/arm/mach-mvebu/coherency.c:123:12:
warning: symbol 'coherency_init' was not declared. Should it be static?
arch/arm/mach-mvebu/pmsu.c:38:5: warning:
symbol 'armada_xp_boot_cpu' was not declared. Should it be static?
arch/arm/mach-mvebu/pmsu.c:61:12: warning:
symbol 'armada_370_xp_pmsu_init' was not declared. Should it be static?
arch/arm/mach-mvebu/platsmp.c:49:13: warning:
symbol 'set_secondary_cpus_clock' was not declared. Should it be static?
arch/arm/mach-mvebu/platsmp.c:97:13: warning:
symbol 'armada_xp_smp_prepare_cpus' was not declared. Should it be static?
arch/arm/mach-mvebu/hotplug.c:24:12: warning:
symbol 'armada_xp_cpu_die' was not declared. Should it be static?
Signed-off-by: NJisheng Zhang <jszhang@marvell.com>
Acked-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

Currently set_secondary_cpus_clock assume the CPU logical ordering
and the MPDIR in DT are same, which is incorrect.

Since the CPU device nodes can be retrieved in the logical ordering
using the DT helper, we can remove the devices tree parsing.

This patch removes DT parsing by making use of of_get_cpu_node.

Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Jason Cooper <jason@lakedaemon.net>
Acked-by: NGregory Clement <gregory.clement@free-electrons.com>
Signed-off-by: NSudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>

arm_dt_init_cpu_maps parses the device tree, validates and sets the
cpu_possible_mask appropriately. It is unnecessary to do another DT
parse to get the number of cpus, use num_possible_cpus instead.

Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: NSudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Acked-by: NGregory Clement <gregory.clement@free-electrons.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

The address decoding window to access the BootROM should not be
allocated programatically, but instead declared in the device tree.
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code.  It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The ->smp_init_cpus() function is called very early during boot, at a
point where dynamic I/O mappings are not yet possible. However, in the
Armada 370/XP implementation of this function, we have to get the
number of CPUs. We used to do that by accessing a hardware register,
which requires relying on a static I/O mapping set up by
->map_io(). Not only this requires hardcoding a virtual address, but
it also prevents us from removing the static I/O mapping.

So this commit changes the way used to get the number of CPUs: we now
use the Device Tree, which is a representation of the hardware, and
provides us the number of available CPUs. This is also more accurate,
because it potentially allows to boot the Linux kernel on only a
number of CPUs given by the Device Tree, instead of unconditionally on
all CPUs.

As a consequence, the coherency_get_cpu_count() function becomes no
longer used, so we remove it.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

The changes needed to migrate the mach-mvebu (Armada 370 and Armada
XP) to the mvebu-mbus driver are fairly minimal, since not many
devices currently supported on those SoCs use address decoding
windows. The only one being the BootROM window, used to bring up
secondary CPUs.

However, this BootROM window needed for SMP brings an important
requirement: the mvebu-mbus driver must be initialized at the
->early_init() time, otherwise the BootROM window cannot be setup
early enough to be ready before the secondary CPUs are started.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

This enables SMP support on the Armada XP processor. It adds the
mandatory functions to support SMP such as: the SMP initialization
functions in platsmp.c, the secondary CPU entry point in headsmp.S and
the CPU hotplug initial support in hotplug.c.
Signed-off-by: NYehuda Yitschak <yehuday@marvell.com>
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>