[PATCH v2 3/5] pinctrl: renesas: r8a77965: Add R8A774B1 PFC support

[Biju Das]

Hi Marek,

> Subject: RE: [PATCH v2 3/5] pinctrl: renesas: r8a77965: Add R8A774B1 PFC
> support
> 
> Hi Marek,
> 
> > Subject: Re: [PATCH v2 3/5] pinctrl: renesas: r8a77965: Add R8A774B1
> > PFC support
> >
> > On 10/14/20 1:29 PM, Biju Das wrote:
> >
> > Hi,
> >
> > [...]
> >
> > >>>> Check with the linux maintainers please, surely there should be
> > >>>> some way to separate the extras in a way that's not too hard to
> > >>>> maintain, and thus reduce the resulting binary size. For U-Boot,
> > >>>> that is quite important already, I think the TFA can only load 1
> > >>>> MiB
> > binary in total.
> > >>>
> > >>> I agree for bootloader size is important. So I will add macros as
> > >>> per your
> > >> suggestion (we don't need to look into linux for this).
> > >>
> > >> The PFC tables and clock tables are the same between U-Boot and
> > >> Linux, so if you only change them in U-Boot, it will make it hard
> > >> to synchronize the tables later with Linux again. Please fix this
> > >> in Linux and
> > synchronize to U-Boot.
> > >
> > > I have posted a patch for optimizing pin control size for RZ/G2N in
> > > Linux [1]
> > >
> > > [1]
> > > https://patchwork.kernel.org/project/linux-renesas-soc/patch/2020101
> > > 41 10238.9600-1-biju.das.jz at bp.renesas.com/
> > >
> > > This approach will save ~ 6KB=(3x 2KB/SoC) of memory on RZ/G2[HMN]
> > > u-
> > boot with multi dtb support.
> > >
> > > 1) By compiling out Automotive parts $ size
> > > drivers/pinctrl/renesas/pfc-r8a77965.o
> > >    text	   data	    bss	    dec	    hex	filename
> > >   46141	      0	      0	  46141	   b43d	drivers/pinctrl/renesas/pfc-
> > r8a77965.o
> > >
> > > 2) without patch
> > > $ size drivers/pinctrl/renesas/pfc-r8a77965.o
> > >    text	   data	    bss	    dec	    hex	filename
> > >   48191	      0	      0	  48191	   bc3f	drivers/pinctrl/renesas/pfc-
> > r8a77965.o
> >
> > Have a look at the size of the image of rcar3_salvator-x_defconfig ,
> > it is just a few kiB short of 1MiB , which is the hard limit. Any size reduction
> helps.
> 
> Yes I agree, we need to look into size reduction for Salvator-XS. But currently
> there is no issue. See the details below.

I have sent a RFC patches to reduce pin control size for RCAR which saves 60KB. 

[1]  https://patchwork.ozlabs.org/project/uboot/patch/20201028103429.3051-7-biju.das.jz@bp.renesas.com/
[2] https://patchwork.ozlabs.org/project/uboot/patch/20201028103429.3051-8-biju.das.jz@bp.renesas.com/
[3] https://patchwork.ozlabs.org/project/uboot/patch/20201028103429.3051-9-biju.das.jz@bp.renesas.com/

Regards,
Biju