ARM: shmobile: use for_each_of_cpu_node iterator

Use the for_each_of_cpu_node iterator to iterate over cpu nodes. This
has the side effect of defaulting to iterating using "cpu" node names in
preference to the deprecated (for FDT) device_type == "cpu".

Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rob Herring <robh@kernel.org>

ARM: shmobile: convert to SPDX identifiers

This patch updates license to use SPDX-License-Identifier
instead of verbose license text.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Always enable ARCH_TIMER on SoCs with A7 and/or A15

R-Mobile APE6, R-Car Gen2, and RZ/G1 SoCs have Cortex-A7 and/or
Cortex-A15 CPU cores, all of which have ARM architectured timers.

Force use of the ARM architectured timer on these SoCs.
This allows to:
- Remove the calls to shmobile_init_delay() from the corresponding
machine vectors,
- Remove a check in timer setup specific to R-Car Gen2,
- Remove a check in shmobile_init_delay().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: timer: Drop support for Cortex A8

Commit edf4100906044225 ("ARM: shmobile: sh7372 dtsi: Remove Legacy
file") removed the DTS for the last shmobile SoC with a Cortex A8 CPU
core (sh7372 aka SH-Mobile AP4), hence drop support for it in the
loops-per-jiffy preset code.

As "div" is always 1 for supported contemporary ARM processors, we can
simplify the code:
- Absorb shmobile_setup_delay_hz(), which was always called with
mult = div = 1,
- Return earlier if the Cortex A7/A15 arch timer exists and support is
enabled.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: timer: Fix preset_lpj leading to too short delays

On all shmobile ARM SoCs, loop-based delays may complete early, which
can be after only 1/3 (Cortex A9) or 1/2 (Cortex A7 or A15) of the
minimum required time.

This is caused by calculating preset_lpj based on incorrect assumptions
about the number of clock cycles per loop:
- All of Cortex A7, A9, and A15 run __loop_delay() at 1 loop per
CPU clock cycle,
- As of commit 11d4bb1bd067f9d0 ("ARM: 7907/1: lib: delay-loop: Add
align directive to fix BogoMIPS calculation"), Cortex A8 runs
__loop_delay() at 1 loop per 2 instead of 3 CPU clock cycles.

On SoCs with Cortex A7 and/or A15 CPU cores, this went unnoticed, as
delays use the ARM arch timer if available. R-Car Gen2 doesn't work if
the arch timer is disabled. However, APE6 can be used without the arch
timer.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Add includes providing forward declarations

make C=1:

arch/arm/mach-shmobile/timer.c:38:13: warning: symbol 'shmobile_init_delay' was not declared. Should it be static?
arch/arm/mach-shmobile/suspend.c:37:29: warning: symbol 'shmobile_suspend_ops' was not declared. Should it be static?
arch/arm/mach-shmobile/suspend.c:44:12: warning: symbol 'shmobile_suspend_init' was not declared. Should it be static?
arch/arm/mach-shmobile/cpufreq.c:13:12: warning: symbol 'shmobile_cpufreq_init' was not declared. Should it be static?

Include "common.h" to fix these.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Remove obsolete earlytimer registration

The last caller of shmobile_earlytimer_init() was removed in commit
c99cd90d98a98aa1 ("ARM: shmobile: r8a7779: Remove legacy SoC code").

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: timer: r8a73a4 and r8a7790 are multi-platform only

Since commits e042681894b62d60 ("ARM: shmobile: r8a7790: Remove legacy
code") and 9d07d414d4c33d86 ("ARM: shmobile: r8a73a4: ape6evm: Remove
legacy platform"), the R-Mobile APE6 and R-Car H2 SoCs are supported by
multiplatform kernels only.
Hence we can drop checks for these SoCs in legacy kernel builds.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: r8a7790: Instantiate GIC from C board code in legacy builds

As of commit 9a1091ef0017c40a ("irqchip: gic: Support hierarchy irq
domain."), the Lager legacy board support is known to be broken.

The IRQ numbers of the GIC are now virtual, and no longer match the
hardcoded hardware IRQ numbers in the legacy platform board code.

To fix this issue specific to non-multiplatform r8a7790 and Lager:
1) Instantiate the GIC from platform board code and also
2) Skip over the DT arch timer as well as
3) Force delay setup based on DT CPU frequency

With these 3 fixes in place interrupts on Lager are now unbroken.

Partially based on legacy GIC fix by Geert Uytterhoeven, thanks to
him for the initial work.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: r8a73a4: Instantiate GIC from C board code in legacy builds

As of commit 9a1091ef0017c40a ("irqchip: gic: Support hierarchy irq
domain."), the APE6EVM legacy board support is known to be broken.

The IRQ numbers of the GIC are now virtual, and no longer match the
hardcoded hardware IRQ numbers in the legacy platform board code.

To fix this issue specific to non-muliplatform r8a73a4 and APE6EVM:
1) Instantiate the GIC from platform board code and also
2) Skip over the DT arch timer as well as
3) Force delay setup based on DT CPU frequency

With these 3 fixes in place interrupts on APE6EVM are now unbroken.

Partially based on legacy GIC fix by Geert Uytterhoeven, thanks to
him for the initial work.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Remove FSF address from copyright headers

The information is already included in the COPYING file in the kernel
sources root directory, we don't want to modify all source files when
the FSF will move to a new address, and I'm tired of seeing the related
checkpatch.pl warnings.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Handle CA7 arch timer delay

Update the delay code to include arch timer checks
for CA7. From a arch timer availability perspective
CA7 should be treated same as CA15.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: support Cortex-A7 in shmobile_init_delay()

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Acked-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Remove shmobile_setup_delay()

All ARM mach-shmobile SoCs and boards now rely on DTS for
CPU Frequency information, so remove the unused function
shmobile_setup_delay(). While at it, make the function
shmobile_setup_delay_hz() static.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Fix device node reference leakage in shmobile_init_delay

The of_find_compatible_node() function returns a new reference to the
found node. Instead of just adding of_node_put() calls, simplify the
code by moving the CPU identification logic inside the loop over cpu
nodes, in order to lower complexity from O(n) to O(1) by replacing
of_find_compatible_node() calls with of_device_is_compatible().

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Set clock frequency in HZ from OF nodes

shmobile_init_delay() looks for OF "clock-frequency" to determine
the delay which is set by calling shmobile_setup_delay().

Unfortunately this seems to be incorrect in detail as
"clock-frequency" node values are in HZ whereas the frequency
argument to shmobile_setup_delay() is in MHz.

Provide a variant of shmobile_setup_delay() that accepts HZ to
correct this problem.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Add shared shmobile_init_delay()

Introduce shmobile_init_delay() that gets CPU specific
parameters from DT and sets up the early delay from
there. This allows us to both remove frequency information
from the C code and consolidate existing code.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: shmobile: Remove unused shmobile_init_time()

Remove shmobile_timer_init() since it now is unused.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: convert arm/arm64 arch timer to use CLKSRC_OF init

This converts arm and arm64 to use CLKSRC_OF DT based initialization for
the arch timer. A new function arch_timer_arch_init is added to allow for
arch specific setup.

This has a side effect of enabling sched_clock on omap5 and exynos5. There
should not be any reason not to use the arch timers for sched_clock.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>

ARM: shmobile: Register ARM architected timer

Register ARM architected timer by default for all mach-shmobile
systems using late timer.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

ARM: delete struct sys_timer

Now that the only field in struct sys_timer is .init, delete the struct,
and replace the machine descriptor .timer field with the initialization
function itself.

This will enable moving timer drivers into drivers/clocksource without
having to place a public prototype of each struct sys_timer object into
include/linux; the intent is to create a single of_clocksource_init()
function that determines which timer driver to initialize by scanning
the device dtree, much like the proposed irqchip_init() at:
http://www.spinics.net/lists/arm-kernel/msg203686.html

Includes mach-omap2 fixes from Igor Grinberg.

Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

ARM / mach-shmobile: Use preset_lpj with calibrate_delay()

Update the mach-shmobile shared delay calibration code for late
timers. All existing in-tree non-DT socs are however using early
timers today and they are unaffected by this change.

The patch modifies shmobile_setup_delay() from using lpj_fine
to preset_lpj. This change allows us to preset the worst case
loops-per-jiffy value to all CPU cores on the system.

The old code which made use of lpj_fine did not affect the
secondary CPU cores which made it impossible to boot on SMP
without early timers.

Needed for SMP SoCs using late timers like EMEV2 or any other
mach-shmobile SMP SoC that makes use of late timers via DT.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM / mach-shmobile: sh73a0 SMP TWD boot regression fix

Fix SMP TWD boot regression on sh73a0 based platforms caused by:

4200b16 ARM: shmobile: convert to twd_local_timer_register() interface

After the merge of the above commit it has been impossible to boot
sh73a0 based SoCs with SMP enabled and CONFIG_HAVE_ARM_TWD=y. The
kernel crashes at smp_init_cpus() timing which is before the console
has been initialized, so to the user this looks like a kernel lock up
without any particular error message.

This patch fixes the regression on sh73a0 by moving the TWD
registration code from smp_init_cpus() to sys_timer->init() time.

This patch removed shmobile_twd_init() which is no longer needed

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM: mach-shmobile: Introduce shmobile_setup_delay()

Add the function shmobile_setup_delay() to let platforms
configure their maximum loops per jiffy delay. With this
jiffies calculation done the dependency on early timer
is removed.

In the future this allows us to assign timers
using the regular driver model via the device tree.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM: shmobile: convert to twd_local_timer_register() interface

Add support for the new smp_twd runtime registration interface
to the shmobile platforms, and remove the old compile-time support.

Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

ARM: mach-shmobile: default to no earlytimer

Now when all SoCs and boards are converted to use
shmobile_earlytimer_init(), change the default behavior
of shmobile_timer.init() from using early timer to
do nothing which is suitable for upcoming DT support.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM: mach-shmobile: add shmobile_earlytimer_init()

Add shmobile_earlytimer_init() that can be used to
enable the earlytimer probing from the SoC code.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

ARM: mach-shmobile: SH-Mobile G3 support.

This adds preliminary support for the SH-Mobile G-series.

The SH-Mobile G-series is a series of ARM/SH multi-core CPUs that aside
from the ARM MPU are primarily composed of existing SH IP blocks.

This includes initial support for the SH7367 (SH-Mobile G3) CPU and
the G3EVM reference board.

Only timer, serial console, and NOR flash are supported at this point.
Patches for the interrupt controller, pinmux support, clock framework
and runtime pm will be submitted as feature patches on top of this.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>