Re: [PATCH net-next v2] net: pcs: rzn1-miic: Correct MODCTRL register offset

From: Geert Uytterhoeven
Date: Thu Aug 21 2025 - 03:12:59 EST


On Wed, 20 Aug 2025 at 19:09, Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> Correct the Mode Control Register (MODCTRL) offset for RZ/N MIIC.
> According to the R-IN Engine and Ethernet Peripherals Manual (Rev.1.30)
> [0], Table 10.1 "Ethernet Accessory Register List", MODCTRL is at offset
> 0x8, not 0x20 as previously defined.
>
> Offset 0x20 actually maps to the Port Trigger Control Register (PTCTRL),
> which controls PTP_MODE[3:0] and RGMII_CLKSEL[4]. Using this incorrect
> definition prevented the driver from configuring the SW_MODE[4:0] bits
> in MODCTRL, which control the internal connection of Ethernet ports. As
> a result, the MIIC could not be switched into the correct mode, leading
> to link setup failures and non-functional Ethernet ports on affected
> systems.
>
> [0] https://www.renesas.com/en/document/mah/rzn1d-group-rzn1s-group-rzn1l-group-users-manual-r-engine-and-ethernet-peripherals?r=1054571
>
> Fixes: 7dc54d3b8d91 ("net: pcs: add Renesas MII converter driver")
> Cc: stable@xxxxxxxxxx
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>

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

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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when I'm talking to journalists I just say "programmer" or something like that.
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