platform_heartbeat is called from the timer interrupt handler, but
there may be no periodic timer interrupts on xtensa, so the frequency of
platform_heartbeat calls may be unrelated to HZ. Drop the callback and
reimplement its only user with a timer.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
- move all constant assignments from local_timer_setup to the definition
of ccount_timer to make it mostly statically initialized;
- drop local function declarations, reorder functions and variables that
reference them.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
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>
There is no point in having an extra type for extra confusion. u64 is
unambiguous.
Conversion was done with the following coccinelle script:
@rem@
@@
-typedef u64 cycle_t;
@fix@
typedef cycle_t;
@@
-cycle_t
+u64
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Convert printk(KERN_* to pr_* and printk's without level to pr_cont.
This fixes torn register dumps, stack dumps, stack traces and timestamps
in the middle of 'Calibrating CPU frequency' message.
Also drop unused show_code and drop false comment about show_stack.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
DT-enabled kernel should have a CPU node connected to a clock. This clock
is the CCOUNT clock. Use old platform_calibrate_ccount call as a fallback
when CPU node cannot be found or has no clock and in non-DT-enabled
configurations.
Drop no longer needed code that updates CPU clock-frequency property in
the DT; drop DT-related code from the platform_calibrate_ccount too.
Move of_clk_init to the top of time_init, so that clocks are initialized
before CCOUNT calibration is attempted.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.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>
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>
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>
Commits 925f5532 (xtensa: ccount based clockevent implementation) and e3f43291
(xtensa: ccount based sched_clock) introduced users of ccount_freq. This
variable doesn't exist when CONFIG_XTENSA_CALIBRATE_CCOUNT is disabled. Add
ccount_freq definition in this case.
Reported-by: Chen Gang <gang.chen@asianux.com>
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>
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 5e427ec2d0 ("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)
are flagged as __cpuinit -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
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 arch/xtensa uses of the __cpuinit macros from
all C files. Currently xtensa does not have any __CPUINIT used in
assembly files.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
IRQ domains provide a mechanism for conversion of linux IRQ numbers to
hardware IRQ numbers and vice versus. It is used by OpenFirmware for
linking device tree objects to their respective interrupt controllers.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>