Hi Prabhakar,
On Mon, Nov 16, 2020 at 9:54 AM Lad, Prabhakar
<prabhakar.csengg@xxxxxxxxx> wrote:
> On Mon, Nov 16, 2020 at 8:34 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > On Tue, Nov 10, 2020 at 1:56 PM Lad Prabhakar
> > <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote:
> > > Describe the RPCSRC internal clock and the RPC[D2] clocks derived from it,
> > > as well as the RPC-IF module clock, in the RZ/G2E (R8A774C0) CPG/MSSR
> > > driver.
> > >
> > > Add new clk type CLK_TYPE_GEN3E3_RPCSRC to register rpcsrc as a fixed
> > > clock on R-Car Gen3 E3 (and also RZ/G2E which is identical to E3 SoC),
> > > parent and the divider is set based on the register value CPG_RPCCKCR[4:3]
> > > (parent is cross verified against MD[4:1] pins) which has been set prior
> > > to booting the kernel.
> > >
> > > MD[4] MD[3] MD[2] MD[1]
> > > 0 0 0 1 -> RPCSRC CLK source is PLL1
> > > 0 0 1 1 -> RPCSRC CLK source is PLL1
> > > 0 1 0 0 -> RPCSRC CLK source is PLL1
> > > 1 0 1 1 -> RPCSRC CLK source is PLL1
> > > x x x x -> For any other values RPCSRC CLK source is PLL0
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > > Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > + switch (value) {
> > > + case 0:
> > > + div = 5;
> > > + break;
> > > + case 1:
> > > + div = 3;
> > > + break;
> > > + case 2:
> > > + parent = clks[core->parent >> 16];
> > > + if (IS_ERR(parent))
> > > + return ERR_CAST(parent);
> > > + div = 8;
> >
> > R-Car D3 is very similar, but uses div = 5 instead of 8.
> > Perhaps this value can be retrieved from cpg_core_clk.div?
> > Of course, we can do that later, when D3 support is added.
> >
> Agreed, should the below be OK ?
>
> #define DEF_FIXED_RPCSRC_E3(_name, _id, _parent0, _parent1, _div)
Fine, but then I would drop the _E3 suffix ;-)
Alternatively, you can just hide the fixed 8 inside the macro, and add a
seperate macro for D3 later.
Up to you.
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
