Re: [PATCH 13/16] clk: renesas: Add CPG core wrapper for RZ/G2L SoC

From: Lad, Prabhakar
Date: Fri May 28 2021 - 03:51:53 EST


Hi Geert,

On Thu, May 27, 2021 at 1:04 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>
> Hi Prabhakar,
>
> On Fri, May 14, 2021 at 9:24 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote:
> > Add CPG core wrapper for RZ/G2L family.
> >
> > Based on a patch in the BSP by Binh Nguyen
> > <binh.nguyen.jz@xxxxxxxxxxx>.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
>
> > --- /dev/null
> > +++ b/drivers/clk/renesas/renesas-rzg2l-cpg.c
>
> > +static int rzg2l_mod_clock_endisable(struct clk_hw *hw, bool enable)
> > +{
> > + struct mstp_clock *clock = to_mod_clock(hw);
> > + struct cpg_mssr_priv *priv = clock->priv;
> > + unsigned int reg = MSSR_OFF(clock->bit) * 4;
>
> The "* 4" here makes it difficult to review the module clock tables.
>
> E.g.
>
> DEF_MOD("gic", R9A07G044_CLK_GIC600,
> R9A07G044_CLK_P1,
> MSSR(5, BIT(0), (BIT(0) | BIT(1)))),
>
> The "5" means the CLK_ON_GIC600 register is at offset CLK_ON_R(5 * 4)
> = 0x514. Removing the "* 4" means you could use
> "MSSR(0x14, BIT(0), (BIT(0) | BIT(1))" instead.
>
> Unless it has unpleasant side effects, I'd even consider putting
> the full CLK_ON offset there, i.e.
> "MSSR(0x514, BIT(0), (BIT(0) | BIT(1))" and change the macros like:
>
> #define CLK_ON_R(reg) (reg)
> #define CLK_MON_R(reg) (0x680 - 0x500 + (reg))
>
OK will do that.

> > --- /dev/null
> > +++ b/drivers/clk/renesas/renesas-rzg2l-cpg.h
>
> > +#define CLK_ON_R(reg) (0x500 + reg)
> > +#define CLK_MON_R(reg) (0x680 + reg)
> > +#define CLK_RST_R(reg) (0x800 + reg)
> > +#define CLK_MRST_R(reg) (0x980 + reg)
>
> The last three don't seem to be documented?
>
I have asked Chris to send the document across.

Cheers,
Prabhakar