Re: [PATCH] can: rcar_canfd: Change the initializing flow for clocks and resets

[Geert Uytterhoeven]

On Thu, 25 Jun 2026 at 15:52, Biju <biju.das.au@xxxxxxxxx> wrote:
> From: Tu Nguyen <tu.nguyen.xg@xxxxxxxxxxx>
>
> Testing CANFD on RZ/G3E shows that many registers do not reset to their
> initial values with the current flow of deasserting resets first and then
> enabling clocks.
>
> Based on the HW manual, clocks should be supplied first and the
> resets deasserted afterward.
>
>  section 7.4.3 Procedure for Activating Modules: RZ/G2L
>  section 4.4.9.3 Procedure for Starting up Units: RZ/G3E
>
> So, update the order of the initializing flow for resets and clocks
> to match the hardware manual, resetting all CANFD registers to their
> initial values. Also update rcar_canfd_global_deinit() to assert
> resets before disabling clocks, so the teardown path mirrors the new
> init ordering.
>
> Fixes: 76e9353a80e9 ("can: rcar_canfd: Add support for RZ/G2L family")
> Signed-off-by: Tu Nguyen <tu.nguyen.xg@xxxxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

As CAN-FD on R-Car does not have rst[pc]_n, this patch has no impact
on R-Car, and I don't have to provide my Tested-by :-)

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