Re: [PATCH/RFC 17/19] arm64: dts: renesas: Add support for Salvator-XS with R-Car M3-W+

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	Magnus Damm <magnus.damm@gmail.com>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	Eugeniu Rosca <roscaeugeniu@gmail.com>,
	Marek Vasut <marek.vasut+renesas@gmail.com>
Subject: Re: [PATCH/RFC 17/19] arm64: dts: renesas: Add support for Salvator-XS with R-Car M3-W+
Date: Wed, 16 Oct 2019 10:54:12 +0200	[thread overview]
Message-ID: <CAMuHMdU2CbuaS6yd8BTmkSx4h_kGF-ca2BRwjUcOaaX8EN02fA@mail.gmail.com> (raw)
In-Reply-To: <20191014175742.GA10194@vmlxhi-102.adit-jv.com>

Hi Eugeniu,

On Mon, Oct 14, 2019 at 7:57 PM Eugeniu Rosca <erosca@de.adit-jv.com> wrote:
> On Mon, Oct 07, 2019 at 12:23:30PM +0200, Geert Uytterhoeven wrote:
> > Add initial support for the Renesas Salvator-X 2nd version development
> > board equipped with an R-Car M3-W+ SiP with 8 (2 x 4) GiB of RAM.
> >
> > The memory map is as follows:
> >   - Bank0: 4GiB RAM : 0x000048000000 -> 0x000bfffffff
> >                     0x000480000000 -> 0x004ffffffff
> >   - Bank1: 4GiB RAM : 0x000600000000 -> 0x006ffffffff
> >
> > Based on a patch in the BSP by Takeshi Kihara
> > <takeshi.kihara.df@renesas.com>.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> >  arch/arm64/boot/dts/renesas/Makefile          |  1 +
> >  .../boot/dts/renesas/r8a77961-salvator-xs.dts | 31 +++++++++++++++++++
> >  2 files changed, 32 insertions(+)
> >  create mode 100644 arch/arm64/boot/dts/renesas/r8a77961-salvator-xs.dts
>
> It is common practice in Renesas BSP to specify the SiP memory
> split by suffixing the DTB names with '-{2,4}x{2,4}g' [1].
>
> Has this ever been discussed on ML?
>
> Here in particular, it would allow M3-W+ 2x4GiB Salvator-XS and
> M3-W+ 2x2GiB (or any other DRAM split flavor of) Salvator-XS to
> coexist in harmony, if the latter pops up at any point.

With mainline U-Boot, the memory configuration is passed from ATF
through U-Boot to Linux, see e.g. "ARM: renesas: Configure DRAM size
from ATF DT fragment" [1], so there's no longer a need to maintain
multiple DTS files.

[1] https://gitlab.denx.de/u-boot/u-boot/commit/175f5027345c7feaa41e8f4201778814bf72fe37

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