Re: [PULL 16/21] hw/timer: Refactor NPCM7XX Timer to use CLK clock

[Peter Maydell]

On Thu, 4 Feb 2021 at 22:38, Hao Wu <wuhaotsh@google.com> wrote:
>
> I don't see this error. It could be some error in the clock that the timer 
> module does not get a correct clock input.
> How do you reproduce this?
>
> On Thu, Feb 4, 2021 at 1:39 AM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>
>> Hi,
>>
>> On Tue, Jan 12, 2021 at 6:20 PM Peter Maydell <peter.maydell@linaro.org>
>> wrote:
>> >
>> > From: Hao Wu <wuhaotsh@google.com>
>> >
>> > This patch makes NPCM7XX Timer to use a the timer clock generated by the
>> > CLK module instead of the magic number TIMER_REF_HZ.
>> >
>> > Reviewed-by: Havard Skinnemoen <hskinnemoen@google.com>
>> > Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
>> > Signed-off-by: Hao Wu <wuhaotsh@google.com>
>> > Message-id: 20210108190945.949196-3-wuhaotsh@google.com
>> > Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
>> > Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> > ---
>> >  include/hw/misc/npcm7xx_clk.h    |  6 -----
>> >  include/hw/timer/npcm7xx_timer.h |  1 +
>> >  hw/arm/npcm7xx.c                 |  5 ++++
>> >  hw/timer/npcm7xx_timer.c         | 39 +++++++++++++++-----------------
>> >  4 files changed, 24 insertions(+), 27 deletions(-)
>>
>> Is that a spurious error (building with Clang)?
>>
>> Running test qtest-arm/npcm7xx_timer-test
>> ERROR:../tests/qtest/npcm7xx_timer-test.c:475:test_periodic_interrupt:
>> assertion failed (tim_read(td, TISR) == tim_timer_bit(td)): (0x00000000
>> == 0x00000004)
>> ERROR:../tests/qtest/npcm7xx_timer-test.c:476:test_periodic_interrupt:
>> 'qtest_get_irq(global_qtest, tim_timer_irq(td))' should be TRUE
>> FAIL 155 qtest-arm/npcm7xx_timer-test
>> /arm/npcm7xx_timer/tim[2]/timer[2]/periodic_interrupt
>> make: *** [Makefile.mtest:1033: run-test-127] Error 1

This intermittent is still with us:

/arm/npcm7xx_timer/tim[2]/timer[0]/periodic_interrupt: **
ERROR:../../tests/qtest/npcm7xx_timer-test.c:475:test_periodic_interrupt:
assertion failed (tim_read(td, TISR) == tim_timer_bit(td)):
(0x00000000 == 0x00000001)
**
ERROR:../../tests/qtest/npcm7xx_timer-test.c:476:test_periodic_interrupt:
'qtest_get_irq(global_qtest, tim_timer_irq(td))' should be TRUE
FAIL

I was able to reproduce it by running the test in a tight loop:

while QTEST_QEMU_BINARY=./build/x86/qemu-system-arm
./build/x86/tests/qtest/npcm7xx_timer-test ; do true ;done

and eventually it hit the assert.

-- PMM