Re: [PATCH 00/12] clocksource: improve Atmel TCB timer driver

[Daniel Lezcano]

Hi Alexandre,

except the comment for 3/12, the series looks good to me.



On 03/04/2019 16:11, Alexandre Belloni wrote:
> Hi,
> 
> This series immproves the Atmel TCB clocksource driver to address the
> most urgent shortcomings:
>  - the current tcb_clksrc driver is probed too late to be able to be used at
>    boot and we now have SoCs that don't have a PIT. They currently are not able
>    to boot an upstream kernel.
>  - using the PIT doesn't work well with preempt-rt because its interrupt is
>    shared (in particular with the UART) and their interrupt flags are
>    incompatible). This also happen with the threadedirq command line
>    switch.
>  - there is currently no high resolution sched_clock.
> 
> The plan is to get those changes upstream as soon as possible as they
> arre fixing real issues that people are facing. There are further
> changes needed on the clocksource driver to try to stop wasting a TCB
> channel.
> the PWM TCB driver will also be changed to actually used the reviewed
> binding and this will allow to get rif of atmel_tclib.
> 
> Alexandre Belloni (12):
>   ARM: at91: move SoC specific definitions to SoC folder
>   misc: atmel_tclib: drop AVR32 support
>   misc: atmel_tclib: move definitions to header file
>   clocksource/drivers/tcb_clksrc: stop depending on atmel_tclib
>   clocksource/drivers/tcb_clksrc: Use tcb as sched_clock
>   ARM: at91: Implement clocksource selection
>   clocksource/drivers/tcb_clksrc: move Kconfig option
>   clocksource/drivers/timer-atmel-pit: rework Kconfig option
>   clocksource/drivers/tcb_clksrc: Rename the file for consistency
>   ARM: configs: at91: unselect PIT
>   misc: atmel_tclib: do not probe already used TCBs
>   clocksource/drivers/timer-atmel-tcb: Use ARRAY_SIZE instead of  
>     hardcoded size
> 
>  arch/arm/configs/at91_dt_defconfig            |   1 +
>  arch/arm/configs/sama5_defconfig              |   1 +
>  arch/arm/mach-at91/Kconfig                    |  23 ++++
>  drivers/clocksource/Kconfig                   |  12 +-
>  drivers/clocksource/Makefile                  |   2 +-
>  .../{tcb_clksrc.c => timer-atmel-tcb.c}       | 123 ++++++++++++------
>  drivers/misc/Kconfig                          |  24 ----
>  drivers/misc/atmel_tclib.c                    |  37 +-----
>  drivers/pwm/pwm-atmel-tcb.c                   |   2 +-
>  .../atmel_tc.h => soc/at91/atmel_tcb.h}       |  25 +++-
>  10 files changed, 146 insertions(+), 104 deletions(-)
>  rename drivers/clocksource/{tcb_clksrc.c => timer-atmel-tcb.c} (81%)
>  rename include/{linux/atmel_tc.h => soc/at91/atmel_tcb.h} (95%)
> 


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