From: Biju Das <biju.das.jz@bp.renesas.com>

Introduce rcar_canfd_compute_data_bit_rate_cfg() for simplifying data bit
rate configuration by replacing function-like macros.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v1->v2:
 * Split from patch#3 for computing data bit rate config separate.
   separate.
 * Replaced RCANFD_DCFG_DBRP->RCANFD_DCFG_DBRP_MASK and used FIELD_PREP to
   extract value.
---
 drivers/net/can/rcar/rcar_canfd.c | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 944b960c0b5e..f56ed8967212 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -169,15 +169,7 @@
 #define RCANFD_CERFL_ERR(x)		((x) & (0x7fff)) /* above bits 14:0 */
 
 /* RSCFDnCFDCmDCFG */
-#define RCANFD_DCFG_DSJW(gpriv, x)	(((x) & ((gpriv)->info->data_bittiming->sjw_max - 1)) << 24)
-
-#define RCANFD_DCFG_DTSEG2(gpriv, x) \
-	(((x) & ((gpriv)->info->data_bittiming->tseg2_max - 1)) << (gpriv)->info->sh->dtseg2)
-
-#define RCANFD_DCFG_DTSEG1(gpriv, x) \
-	(((x) & ((gpriv)->info->data_bittiming->tseg1_max - 1)) << (gpriv)->info->sh->dtseg1)
-
-#define RCANFD_DCFG_DBRP(x)		(((x) & 0xff) << 0)
+#define RCANFD_DCFG_DBRP_MASK		GENMASK(7, 0)
 
 /* RSCFDnCFDCmFDCFG */
 #define RCANFD_GEN4_FDCFG_CLOE		BIT(30)
@@ -1406,6 +1398,19 @@ static inline u32 rcar_canfd_compute_nominal_bit_rate_cfg(struct rcar_canfd_chan
 	return (ntseg1 | nbrp | nsjw | ntseg2);
 }
 
+static inline u32 rcar_canfd_compute_data_bit_rate_cfg(const struct rcar_canfd_hw_info *info,
+						       u16 tseg1, u16 brp, u16 sjw, u16 tseg2)
+{
+	u32 dtseg2, dtseg1, dsjw, dbrp;
+
+	dtseg2 = (tseg2 & (info->data_bittiming->tseg2_max - 1)) << info->sh->dtseg2;
+	dtseg1 = (tseg1 & (info->data_bittiming->tseg1_max - 1)) << info->sh->dtseg1;
+	dsjw = (sjw & (info->data_bittiming->sjw_max - 1)) << 24;
+	dbrp = FIELD_PREP(RCANFD_DCFG_DBRP_MASK, brp);
+
+	return (dtseg1 | dbrp | dsjw | dtseg2);
+}
+
 static void rcar_canfd_set_bittiming(struct net_device *ndev)
 {
 	u32 mask = RCANFD_FDCFG_TDCO | RCANFD_FDCFG_TDCE | RCANFD_FDCFG_TDCOC;
@@ -1435,10 +1440,7 @@ static void rcar_canfd_set_bittiming(struct net_device *ndev)
 	sjw = dbt->sjw - 1;
 	tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
 	tseg2 = dbt->phase_seg2 - 1;
-
-	cfg = (RCANFD_DCFG_DTSEG1(gpriv, tseg1) | RCANFD_DCFG_DBRP(brp) |
-	       RCANFD_DCFG_DSJW(gpriv, sjw) | RCANFD_DCFG_DTSEG2(gpriv, tseg2));
-
+	cfg = rcar_canfd_compute_data_bit_rate_cfg(gpriv->info, tseg1, brp, sjw, tseg2);
 	writel(cfg, &gpriv->fcbase[ch].dcfg);
 
 	/* Transceiver Delay Compensation */
-- 
2.43.0

Hi Biju,

On Thu, 21 Aug 2025 at 16:14, Biju <biju.das.au@gmail.com> wrote:
> From: Biju Das <biju.das.jz@bp.renesas.com>
>
> Introduce rcar_canfd_compute_data_bit_rate_cfg() for simplifying data bit
> rate configuration by replacing function-like macros.
>
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v1->v2:
>  * Split from patch#3 for computing data bit rate config separate.
>    separate.
>  * Replaced RCANFD_DCFG_DBRP->RCANFD_DCFG_DBRP_MASK and used FIELD_PREP to
>    extract value.

Thanks for your patch!

For correctness:
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

But I have the same comments as for "[PATCH v2 3/4] can: rcar_canfd:
Simplify nominal bit rate config".

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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