APPLIED: [SRU][K/Unstable][PATCH 0/1] Compile SiFive PWM driver as a module

[Dimitri John Ledkov]

Applied to unstable & kinetic.

On Mon, 10 Oct 2022 at 13:46, Tim Gardner <tim.gardner at canonical.com> wrote:
>
> On 10/10/22 04:46, Emil Renner Berthing wrote:
> > [ Impact ]
> >
> >   * When adding earlycon to the kernel command line on the
> >     SiFive Unmatched board the serial console will print garbage
> >     halfway through booting until entering userspace and other
> >     other drivers are loaded.
> >
> >   * The problem is the UART driver doesn't claim its clocks
> >     properly so the PWM driver will turn off the parent clock
> >     until PWM is needed for the LEDs on the board.
> >
> >   * Compiling the PWM driver as a module so it will be loaded
> >     at the same time the LED drivers are loaded is a workaround
> >     until the following patch is backported
> >     643792048ee8 ("serial: sifive: enable clocks for UART when probed")
> >
> >   * Only the SoCs on the SiFive Unleashed and Unmatched boards use
> >     this PWM driver, but none of them need it at boot time, so should
> >     be harmless.
> >
> > [ Test Plan ]
> >
> >   * Add earlycon and watch the serial console while booting.
> >
> >   * Test that PWM leds still work after the PWM driver module is loaded.
> >
> > [ Where problems could occur ]
> >
> >   * There might be a hidden dependency on loading the PWM driver early.
> >
> > Emil Renner Berthing (1):
> >    UBUNTU: [Config] Set CONFIG_PWM_SIFIVE=m for riscv64
> >
> >   debian.master/config/annotations          | 2 +-
> >   debian.master/config/config.common.ubuntu | 2 +-
> >   2 files changed, 2 insertions(+), 2 deletions(-)
> >
> Acked-by: Tim Gardner <tim.gardner at canonical.com>
> --
> -----------
> Tim Gardner
> Canonical, Inc
>
>
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-- 
okurrr,

Dimitri