[PATCH v5 1/2] arm: rmobile: Add RZ/G2[HMNE] SoC support

[Biju Das]

Hi Marek,

> -----Original Message-----
> From: Marek Vasut <marek.vasut at gmail.com>
> Sent: 04 November 2020 19:24
> To: Biju Das <biju.das.jz at bp.renesas.com>; Nobuhiro Iwamatsu
> <iwamatsu at nigauri.org>
> Cc: u-boot at lists.denx.de; Chris Paterson <Chris.Paterson2 at renesas.com>;
> Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj at bp.renesas.com>
> Subject: Re: [PATCH v5 1/2] arm: rmobile: Add RZ/G2[HMNE] SoC support
> 
> On 11/3/20 11:06 AM, Biju Das wrote:
> > Hi Marek,
> 
> Hi,
> 
> [...]
> 
> >>> On the next version, I will send Renesas SoC identification driver,
> >>> which supports caching family type which can be used to provide
> >>> unique
> >> identification for CPU type.
> >>
> >> Please make sure to check it on RCar2 as well, those use SPL and the
> >> SPL size is quite limited.
> >
> > Currently SoC identification driver is enabled only for RZ/G2 boards and
> support is added to both R-Car Gen3 and RZ/G2 devices.
> >
> > For the disabled case, the UCLASS-SOC class functions are inlined to
> "NULL"  for soc_device_match and rest of the api's it is "-ENOSYS".
> >
> > I agree, in future we need to add support for RCar2 as well, since we
> are going to add u-boot support for RZ/G1 devices.
> > Please find the size details related to R-Car Gen2(by adding support for
> R-Car M2-W and RZ/G1M SoC).
> >
> > There is increase of 944 bytes, for R-Car Gen2 device, if we enable
> Renesas SoC identification driver for Gen2 devices.
> >
> > Current u-boot-sh/master
> > -----------------------------------
> > $ ls -al u-boot.bin
> > -rw-r--r-- 1 biju biju 523001 Nov  3 09:16 u-boot.bin
> >
> > Current u-boot-sh/master + SoC renesas driver (R-Car M2-W enabled only
> > case)
> > ----------------------------------------------------------------------
> > ----------------------
> > $ ls -al u-boot.bin
> > -rw-r--r-- 1 biju biju 523945 Nov  3 09:47 u-boot.bin
> >
> > If you agree, we will add support for Gen2 to SoC identification driver
> later. Currently there is no users for using it.
> > Please let me know.
> 
> The problem on Gen2 isn't the size of u-boot.bin , but of spl/u-boot-
> spl.bin . That one is severely limited and I don't think it's realistic to
> add any sort of SoC identification driver into it. In fact, I think even
> the DM is somehow reduced in there.

If you see the make file , soc identification driver is disabled for spl/u-boot.

obj-$(CONFIG_$(SPL_)SOC_DEVICE_RENESAS) += soc_renesas.o

So I think we are having same understanding not to add soc identification driver for spl/uboot.
Please let me know, if you think other wise.

Regards,
Biju