Re: [RFC PATCH 1/4] pinctrl: renesas: rzg2l: Include pinmap in RZG2L_GPIO_PORT_PACK() macro

[Lad, Prabhakar]

Hi Biju,

On Tue, Jul 4, 2023 at 9:30 AM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
>
> Hi Prabhakar,
>
> > -----Original Message-----
> > From: Prabhakar <prabhakar.csengg@xxxxxxxxx>
> > Sent: Friday, June 30, 2023 1:05 PM
> > To: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; Magnus Damm
> > <magnus.damm@xxxxxxxxx>
> > Cc: Rob Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski
> > <krzysztof.kozlowski+dt@xxxxxxxxxx>; Linus Walleij
> > <linus.walleij@xxxxxxxxxx>; linux-renesas-soc@xxxxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; linux-riscv@xxxxxxxxxxxxxxxxxxx; linux-
> > kernel@xxxxxxxxxxxxxxx; linux-gpio@xxxxxxxxxxxxxxx; Biju Das
> > <biju.das.jz@xxxxxxxxxxxxxx>; Prabhakar <prabhakar.csengg@xxxxxxxxx>;
> > Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > Subject: [RFC PATCH 1/4] pinctrl: renesas: rzg2l: Include pinmap in
> > RZG2L_GPIO_PORT_PACK() macro
> >
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> >
> > Currently we assume all the port pins are sequential ie always PX_0 to
> > PX_n (n=1..7) exist, but on RZ/Five SoC we have additional pins P19_1 to
> > P28_5 which have holes in them, for example only one pin on port19 is
> > available and that is P19_1 and not P19_0.
> >
> > So to handle such cases include pinmap for each port which would
> > indicate the pin availability on each port. With this we also get
> > additional pin validation, for example on the RZ/G2L SOC P0 has two pins
> > P0_1 and P0_0 but with DT/SYSFS could use the P0_2-P0_7.
> >
> > While at it, update rzg2l_validate_gpio_pin() to use the port pinmap to
> > validate the gpio pin.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > ---
> >  drivers/pinctrl/renesas/pinctrl-rzg2l.c | 167 ++++++++++++------------
> >  1 file changed, 86 insertions(+), 81 deletions(-)
> >
> > diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > index 9511d920565e..a0c2e585e765 100644
> > --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c
> > @@ -67,10 +67,12 @@
> >                                        PIN_CFG_FILCLKSEL)
> >
> >  /*
> > - * n indicates number of pins in the port, a is the register index
> > - * and f is pin configuration capabilities supported.
> > + * m indicates the bitmap of supported pins, n indicates number
> > + * of pins in the port, a is the register index and f is pin
> > + * configuration capabilities supported.
> >   */
> > -#define RZG2L_GPIO_PORT_PACK(n, a, f)        (((n) << 28) | ((a) << 20) |
> > (f))
> > +#define RZG2L_GPIO_PORT_PACK(m, n, a, f)     ((UL(m) << 32) | (UL(n) << 28)
> > | ((a) << 20) | (f))
> > +#define RZG2L_GPIO_PORT_GET_PINMAP(x)        (((x) & GENMASK(39, 32)) >> 32)
> >  #define RZG2L_GPIO_PORT_GET_PINCNT(x)        (((x) & GENMASK(30, 28)) >> 28)
> >  #define RZG2L_GPIO_PORT_GET_INDEX(x) (((x) & GENMASK(26, 20)) >> 20)
> >  #define RZG2L_GPIO_PORT_GET_CFGS(x)  ((x) & GENMASK(19, 0))
> > @@ -129,7 +131,7 @@ struct rzg2l_dedicated_configs {
> >
> >  struct rzg2l_pinctrl_data {
> >       const char * const *port_pins;
> > -     const u32 *port_pin_configs;
> > +     const u64 *port_pin_configs;
>
> Can this be SoC specific? Only for RZ/Five you need this changes.
> Others SoCs like RZ/{G2L,G2LC,V2L and G2UL) still work with u32* as there
> is no holes. With this change memory usage is doubled as we change from
> u32->u64.
>
This is to avoid writing to undocumented registers so I have added for
all the SoCs. For example on the RZ/G2L SOC P0 has two pins P0_1 and
P0_0 but DT/SYSFS could use the P0_2-P0_7. This patch restricts users
to use only available GPIO pins.

Cheers,
Prabhakar