Re: [PATCH v4 0/7] Renesas RZ/G2L IRQC support

["Lad, Prabhakar" <prabhakar.csengg@gmail.com>]

On Wed, May 18, 2022 at 10:10 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Wed, May 18, 2022 at 9:29 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> >
> > Hi All,
> >
> > The RZ/G2L Interrupt Controller is a front-end for the GIC found on
> > Renesas RZ/G2L SoC's with below pins:
> > - IRQ sense select for 8 external interrupts, mapped to 8 GIC SPI
> >   interrupts
> > - GPIO pins used as external interrupt input pins out of GPIOINT0-122 a
> >   maximum of only 32 can be mapped to 32 GIC SPI interrupts,
> > - NMI edge select.
> >
> >                                                              _____________
> >                                                              |    GIC     |
> >                                                              |  ________  |
> >                                       ____________           | |        | |
> > NMI --------------------------------->|          |  SPI0-479 | | GIC-600| |
> >              _______                  |          |------------>|        | |
> >              |      |                 |          |  PPI16-31 | |        | |
> >              |      | IRQ0-IRQ7       |   IRQC   |------------>|        | |
> > P0_P48_4 --->| GPIO |---------------->|          |           | |________| |
> >              |      |GPIOINT0-122     |          |           |            |
> >              |      |---------------->| TINT0-31 |           |            |
> >              |______|                 |__________|           |____________|
> >
> > The proposed patches add hierarchical IRQ domain, one in IRQC driver and
> > another in pinctrl driver. Upon interrupt requests map the interrupt to
> > GIC. Out of GPIOINT0-122 only 32 can be mapped to GIC SPI, this mapping is
> > handled by the pinctrl and IRQC driver.
>
> Where is the explanation on why valid_mask can't be used instead?
>
The .valid_mask option is one time setting but what I need is
something dynamic i.e. out of 392 GPIO pins any 32 can be used as an
interrupt pin. Also with this patch we also save on memory here [0].

[0] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/kernel/irq/irqdomain.c?h=next-20220518#n153

Cheers,
Prabhakar
>
> --
> With Best Regards,
> Andy Shevchenko