[ Upstream commit 4fe8713b873fc881284722ce4ac47995de7cf62c ]

ccount_timer_shutdown is called from the atomic context in the
secondary_start_kernel, resulting in the following BUG:

BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1
Preemption disabled at:
  secondary_start_kernel+0xa1/0x130
Call Trace:
  ___might_sleep+0xe7/0xfc
  __might_sleep+0x41/0x44
  synchronize_irq+0x24/0x64
  disable_irq+0x11/0x14
  ccount_timer_shutdown+0x12/0x20
  clockevents_switch_state+0x82/0xb4
  clockevents_exchange_device+0x54/0x60
  tick_check_new_device+0x46/0x70
  clockevents_register_device+0x8c/0xc8
  clockevents_config_and_register+0x1d/0x2c
  local_timer_setup+0x75/0x7c
  secondary_start_kernel+0xb4/0x130
  should_never_return+0x32/0x35

Use disable_irq_nosync instead of disable_irq to avoid it.
This is safe because the ccount timer IRQ is per-CPU, and once IRQ is
masked the ISR will not be called.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Seeing the 'of' characters in a symbol that is being called from
ACPI seems to freak out people. So let's do a bit of pointless
renaming so that these folks do feel at home.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Migrate xtensa driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Now that ccount_freq is used in udelay and ndelay it needs to be
exported in order to be available to modules.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

The 32 bit sched_clock interface now supports 64 bits. Upgrade
to the 64 bit function to allow us to remove the 32 bit
registration interface.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

PIC irq_ack doesn't clear timer IRQ, because timer interrupt handler
usually set up new timer by writing to ccompare register and thus
clearing timer IRQ. However timer may not be set up in the IRQ handler,
e.g. with tickless idle on SMP, or when CPU is going offline, leaving
timer IRQ raised and making do_interrupt attempting to handle it
forever.

To fix this always write current value of ccompare SR chosen to be linux
timer back to that SR on entry to timer interrupt handler.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

Provide per-cpu ccount_timer objects and use them appropriately.
Extract per-cpu clockevent setup function.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

This allows ccount to be used as highres timer.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

Use ccount_freq directly to make the code a little more readable.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>