Re: [PATCH v2 0/7] soc: renesas: Identify SoC and register with the SoC bus

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Mon, Oct 31, 2016 at 12:30 PM, Geert Uytterhoeven
<geert+renesas@glider.be> wrote:
> Some Renesas SoCs may exist in different revisions, providing slightly
> different functionalities (e.g. R-Car H3 ES1.x and ES2.0), and behavior
> (errate and quirks).  This needs to be catered for by drivers and/or
> platform code.  The recently proposed soc_device_match() API seems like
> a good fit to handle this.
>
> This patch series implements the core infrastructure to provide SoC and
> revision information through the SoC bus for Renesas ARM SoCs. It
> consists of 7 patches:
>   - Patches 1-4 provide soc_device_match(), with some related fixes,
>   - Patches 5-7 implement identification of Renesas SoCs and
>     registration with the SoC bus,
>
> Changes compared to v1:
>   - Add Acked-by,
>   - New patches:
>       - "[4/7] base: soc: Provide a dummy implementation of
>                soc_device_match()",
>       - "[5/7] ARM: shmobile: Document DT bindings for CCCR and PRR",
>       - "[6/7] arm64: dts: r8a7795: Add device node for PRR"
>         (more similar patches available, I'm not yet spamming you all
>          with them),
>   - Drop SoC families and family names; use fixed "Renesas" instead,
>   - Drop EMEV2, which doesn't have a chip ID register, and doesn't share
>     devices with other SoCs,
>   - Drop RZ/A1H and R-CAR M1A, which don't have chip ID registers (for
>     M1A: not accessible from the ARM core?),
>   - On arm, move "select SOC_BUS" from ARCH_RENESAS to Kconfig symbols
>     for SoCs that provide a chip ID register,
>   - Build renesas-soc only if SOC_BUS is enabled,
>   - Use "renesas,prr" and "renesas,cccr" device nodes in DT if
>     available, else fall back to hardcoded addresses for compatibility
>     with existing DTBs,
>   - Remove verification of product IDs; just print the ID instead,
>   - Don't register the SoC bus if the chip ID register is missing,
>   - Change R-Mobile APE6 fallback to use PRR instead of CCCR (it has
>     both).
>
> Merge strategy:
>   - In theory, patches 1-4 should go through Greg's driver core tree.
>     But it's a hard dependency for all users.
>     If people agree, I can provide an immutable branch in my
>     renesas-drivers repository, to be merged by all interested parties.
>     So far I'm aware of Freescale/NXP, and Renesas.

And Samsung.
Shall I create the immutable branch now?

Thanks!

>   - Patches 5-7 obviously have to go through Simon's Renesas tree (after
>     merging the soc_device_match() core), and arm-soc.
>
> Tested on (machine, soc_id, optional revision):
>     EMEV2 KZM9D Board, emev2
>     Genmai, r7s72100
>     APE6EVM, r8a73a4, ES1.0
>     armadillo 800 eva, r8a7740, ES2.0
>     bockw, r8a7778
>     marzen, r8a7779, ES1.0
>     Lager, r8a7790, ES1.0
>     Koelsch, r8a7791, ES1.0
>     Porter, r8a7791, ES3.0
>     Blanche, r8a7792, ES1.1
>     Gose, r8a7793, ES1.0
>     Alt, r8a7794, ES1.0
>     Renesas Salvator-X board based on r8a7795, r8a7795, ES1.0
>     Renesas Salvator-X board based on r8a7795, r8a7795, ES1.1
>     Renesas Salvator-X board based on r8a7796, r8a7796, ES1.0
>     KZM-A9-GT, sh73a0, ES2.0
>
> For your convenience, this series (incl. more DT updates to add device
> nodes for CCCR and PRR to all other Renesas ARM SoCs) is also available
> in the topic/renesas-soc-id-v2 branch of my renesas-drivers git
> repository at
> git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git
> Its first user is support for R-Car H3 ES2.0 in branch
> topic/r8a7795-es2-v1-rebased2.
>
> Thanks for your comments!
>
> Arnd Bergmann (1):
>   base: soc: Introduce soc_device_match() interface
>
> Geert Uytterhoeven (6):
>   base: soc: Early register bus when needed
>   base: soc: Check for NULL SoC device attributes
>   base: soc: Provide a dummy implementation of soc_device_match()
>   ARM: shmobile: Document DT bindings for CCCR and PRR
>   arm64: dts: r8a7795: Add device node for PRR
>   soc: renesas: Identify SoC and register with the SoC bus
>
>  Documentation/devicetree/bindings/arm/shmobile.txt |  26 +++++
>  arch/arm/mach-shmobile/Kconfig                     |   3 +
>  arch/arm64/Kconfig.platforms                       |   1 +
>  arch/arm64/boot/dts/renesas/r8a7795.dtsi           |   5 +
>  drivers/base/Kconfig                               |   1 +
>  drivers/base/soc.c                                 |  79 +++++++++++++
>  drivers/soc/renesas/Makefile                       |   2 +
>  drivers/soc/renesas/renesas-soc.c                  | 130 +++++++++++++++++++++
>  include/linux/sys_soc.h                            |   9 ++
>  9 files changed, 256 insertions(+)
>  create mode 100644 drivers/soc/renesas/renesas-soc.c

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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