Hi Biju,
On Thu, 21 Aug 2025 at 16:14, Biju <biju.das.au@xxxxxxxxx> wrote:
> From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
>
> The calculation formula for nominal bit rate of classical CAN is same as
> that of nominal bit rate of CANFD on the RZ/G3E SoC compared to other SoCs.
> Add shared_bittiming variable to struct rcar_canfd_hw_info to handle this
> difference.
>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> Reviewed-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
Thanks for your patch!
> --- a/drivers/net/can/rcar/rcar_canfd.c
> +++ b/drivers/net/can/rcar/rcar_canfd.c
> @@ -461,6 +461,7 @@ struct rcar_canfd_hw_info {
> unsigned ch_interface_mode:1; /* Has channel interface mode */
> unsigned shared_can_regs:1; /* Has shared classical can registers */
> unsigned external_clk:1; /* Has external clock */
> + unsigned shared_bittiming:1; /* Has shared nominal bittiming constants */
> };
>
> /* Channel priv data */
> @@ -632,6 +633,7 @@ static const struct rcar_canfd_hw_info rcar_gen3_hw_info = {
> .ch_interface_mode = 0,
> .shared_can_regs = 0,
> .external_clk = 1,
> + .shared_bittiming = 0,
> };
>
> static const struct rcar_canfd_hw_info rcar_gen4_hw_info = {
> @@ -649,6 +651,7 @@ static const struct rcar_canfd_hw_info rcar_gen4_hw_info = {
> .ch_interface_mode = 1,
> .shared_can_regs = 1,
> .external_clk = 1,
> + .shared_bittiming = 0,
I could find no stricter limitation of the bit timings in classical
CAN mode on R-Car Gen4, so it looks like this should be 1, too...
> };
>
> static const struct rcar_canfd_hw_info rzg2l_hw_info = {
> @@ -666,6 +669,7 @@ static const struct rcar_canfd_hw_info rzg2l_hw_info = {
> .ch_interface_mode = 0,
> .shared_can_regs = 0,
> .external_clk = 1,
> + .shared_bittiming = 0,
> };
>
> static const struct rcar_canfd_hw_info r9a09g047_hw_info = {
> @@ -683,6 +687,7 @@ static const struct rcar_canfd_hw_info r9a09g047_hw_info = {
> .ch_interface_mode = 1,
> .shared_can_regs = 1,
> .external_clk = 0,
> + .shared_bittiming = 1,
> };
>
> /* Helper functions */
> @@ -1912,7 +1917,10 @@ static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
> priv->can.fd.do_get_auto_tdcv = rcar_canfd_get_auto_tdcv;
> } else {
> /* Controller starts in Classical CAN only mode */
> - priv->can.bittiming_const = &rcar_canfd_bittiming_const;
> + if (gpriv->info->shared_bittiming)
... hence you can just check the existing shared_can_regs flag here,
and don't need to introduce a new flag for shared bittimings?
> + priv->can.bittiming_const = gpriv->info->nom_bittiming;
> + else
> + priv->can.bittiming_const = &rcar_canfd_bittiming_const;
> priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING;
> }
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
