[PATCH v2 02/15] soc: renesas: Add SYSC driver for Renesas RZ family

[Geert Uytterhoeven]

On Fri, Nov 29, 2024 at 9:54 AM Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> On Fri, Nov 29, 2024 at 9:48 AM Claudiu Beznea <claudiu.beznea at tuxon.dev> wrote:
> > On 28.11.2024 17:24, Geert Uytterhoeven wrote:
> > > On Tue, Nov 26, 2024 at 10:21 AM Claudiu <claudiu.beznea at tuxon.dev> wrote:
> > >> From: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
> > >>
> > >> The RZ/G3S system controller (SYSC) has various registers that control
> > >> signals specific to individual IPs. IP drivers must control these signals
> > >> at different configuration phases.
> > >>
> > >> Add SYSC driver that allows individual SYSC consumers to control these
> > >> signals. The SYSC driver exports a syscon regmap enabling IP drivers to
> > >> use a specific SYSC offset and mask from the device tree, which can then be
> > >> accessed through regmap_update_bits().
> > >>
> > >> Currently, the SYSC driver provides control to the USB PWRRDY signal, which
> > >> is routed to the USB PHY. This signal needs to be managed before or after
> > >> powering the USB PHY off or on.
> > >>
> > >> Other SYSC signals candidates (as exposed in the the hardware manual of the
> > >>
> > >> * PCIe:
> > >> - ALLOW_ENTER_L1 signal controlled through the SYS_PCIE_CFG register
> > >> - PCIE_RST_RSM_B signal controlled through the SYS_PCIE_RST_RSM_B
> > >>   register
> > >> - MODE_RXTERMINATION signal controlled through SYS_PCIE_PHY register
> > >>
> > >> * SPI:
> > >> - SEL_SPI_OCTA signal controlled through SYS_IPCONT_SEL_SPI_OCTA
> > >>   register
> > >>
> > >> * I2C/I3C:
> > >> - af_bypass I2C signals controlled through SYS_I2Cx_CFG registers
> > >>   (x=0..3)
> > >> - af_bypass I3C signal controlled through SYS_I3C_CFG register
> > >>
> > >> * Ethernet:
> > >> - FEC_GIGA_ENABLE Ethernet signals controlled through SYS_GETHx_CFG
> > >>   registers (x=0..1)
> > >>
> > >> As different Renesas RZ SoC shares most of the SYSC functionalities
> > >> available on the RZ/G3S SoC, the driver if formed of a SYSC core
> > >> part and a SoC specific part allowing individual SYSC SoC to provide
> > >> functionalities to the SYSC core.
> > >>
> > >> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
> > >
> > >> --- /dev/null
> > >> +++ b/drivers/soc/renesas/r9a08g045-sysc.c
> > >> @@ -0,0 +1,31 @@
> > >> +// SPDX-License-Identifier: GPL-2.0
> > >> +/*
> > >> + * RZ/G3S System controller driver
> > >> + *
> > >> + * Copyright (C) 2024 Renesas Electronics Corp.
> > >> + */
> > >> +
> > >> +#include <linux/array_size.h>
> > >> +#include <linux/bits.h>
> > >> +#include <linux/init.h>
> > >> +
> > >> +#include "rz-sysc.h"
> > >> +
> > >> +#define SYS_USB_PWRRDY         0xd70
> > >> +#define SYS_USB_PWRRDY_PWRRDY_N        BIT(0)
> > >> +#define SYS_MAX_REG            0xe20
> > >> +
> > >> +static const struct rz_sysc_signal_init_data rzg3s_sysc_signals_init_data[] __initconst = {
> > >
> > > This is marked __initconst...
> > >
> > >> +       {
> > >> +               .name = "usb-pwrrdy",
> > >> +               .offset = SYS_USB_PWRRDY,
> > >> +               .mask = SYS_USB_PWRRDY_PWRRDY_N,
> > >> +               .refcnt_incr_val = 0
> > >> +       }
> > >> +};
> > >> +
> > >> +const struct rz_sysc_init_data rzg3s_sysc_init_data = {
> > >
> > > ... but this is not __init, causing a section mismatch.
> >
> > Do you know if there is a way to detect this?
>
> The kernel should tell you during the build...

Sorry, I hit send too early; I was still verifying this...
And it indeed doesn't trigger, strange...

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds