[PATCH v14 01/18] irqchip/sifive-plic: Convert PLIC driver into a platform driver

[Anup Patel]

On Wed, Apr 3, 2024 at 9:19 PM Lad, Prabhakar
<prabhakar.csengg at gmail.com> wrote:
>
> On Wed, Apr 3, 2024 at 3:17 PM Anup Patel <apatel at ventanamicro.com> wrote:
> >
> > On Wed, Apr 3, 2024 at 2:01 PM Lad, Prabhakar
> > <prabhakar.csengg at gmail.com> wrote:
> > >
> > > Hi Anup,
> > >
> > > On Thu, Feb 22, 2024 at 9:41 AM Anup Patel <apatel at ventanamicro.com> wrote:
> > > >
> > > > The PLIC driver does not require very early initialization so convert
> > > > it into a platform driver.
> > > >
> > > > After conversion, the PLIC driver is probed after CPUs are brought-up
> > > > so setup cpuhp state after context handler of all online CPUs are
> > > > initialized otherwise PLIC driver crashes for platforms with multiple
> > > > PLIC instances.
> > > >
> > > > Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> > > > ---
> > > >  drivers/irqchip/irq-sifive-plic.c | 101 ++++++++++++++++++------------
> > > >  1 file changed, 61 insertions(+), 40 deletions(-)
> > > >
> > > This patch seems to have broken things on RZ/Five SoC, after reverting
> > > this patch I get to boot it back again on v6.9-rc2. Looks like there
> > > is some probe order issue after switching to platform driver?
> >
> > Yes, this is most likely related to probe ordering based on your DT.
> >
> > Can you share the failing boot log and DT ?
>
> non working case, https://paste.debian.net/1312947/
> after reverting, https://paste.debian.net/1312948/
> (attached is the DTB)

One potential problem is that
drivers/clocksource/renesas-ostm.c is probed early
using TIMER_OF_DECLARE() but the timer interrupt
is connected to PLIC which is probed late hence the
timer probe will fail.

We have two possible options:
1) Disable OSTM nodes
2) Improve the OSTM driver to probe like a
    regular platform device on RISC-V

Regards,
Anup