Re: [PATCH RFC 2/2] mfd: add Renesas RPC-IF driver

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

Hi Lee,

On Tue, Jun 18, 2019 at 11:57 AM Lee Jones <lee.jones@xxxxxxxxxx> wrote:
> On Tue, 18 Jun 2019, Geert Uytterhoeven wrote:
> > On Tue, Jun 18, 2019 at 11:20 AM Lee Jones <lee.jones@xxxxxxxxxx> wrote:
> > > So is an RPC-IF a real hardware device.  Can you share the datasheet?
> >
> > Unfortunately the datasheet for the R-Car Gen3 and RZ/G2 SoCs is
> > not yet public.
>
> When will it be public?

Dunno. RZ/G1 documentation became public a few months after the SoC
release.

> Do you have access to it?

Yes I do.

> > However, a very similar hardware block is present in the RZ/A2M SoC.
> > Please see Chapter 20 ("SPI Multi I/O Bus Controller") of the "RZ/A2M Group
> > User’s Manual: Hardware", which you can download from
> > https://www.renesas.com/eu/en/products/microcontrollers-microprocessors/rz/rza/rza2m.html#documents
>
>   "The SPI multi I/O bus controller enables the direct connection of
>    serial flash, OctaFlashTM, XccelaTM flash, or HyperFlashTM memory
>    devices to this LSI chip.
>
>    This module allows the connected serial flash, OctaFlashTM, XccelaTM
>    flash, or HyperFlashTM memory devices to be accessed by reading the
>    external address space, or using Manual mode to transmit and receive
>    data."
>
> Looks like a flash device to me.

The external address space is a small window.

> Can the SPI portion be used to connect generic SPI devices?

I'll defer that to the people who worked on the driver...

Gr{oetje,eeting}s,

                        Geert

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

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