Re: [PATCH net-next v5 2/3] ptp: Add driver for R-Car Gen4

Vadim Fedorenko <[email protected]> Tue, 21 Jul 2026 15:36:09 +0100
Newsgroups org.kernel.vger.linux-renesas-soc,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel,org.kernel.vger.netdev
Message-ID <[email protected]>
On 21/07/2026 14:29, Niklas Söderlund wrote:
> Add driver for the gPTP timer found on R-Car Gen4 devices. The timer is
> system-wide and shared by different Ethernet devices on each Gen4
> platform. The operation of the timer is however not completely in
> depended of the systems Ethernet devices.
> 
>    - On R-Car S4 is gated by the RSWITCH Ethernet module clock.
> 
>    - On R-Car V4H is gated by the RTSN Ethernet module clock.
> 
>    - On R-Car V4M is gated by its own module clock, the system have
>      neither RTSN or RSWITCH device. But the module clock is the same as
>      RTSN on V4H and the documentation referees to it as tsn (EtherTSN).
> 
> The gPTP device do have its own register space on all three platforms.
> But on S4 and V4H it will share its clock and reset property with
> RSWITCH or RTSN, respectively.
> 
> Signed-off-by: Niklas Söderlund <[email protected]>
> ---
> * Changes since v4
> - Drop mod_devicetable.h include.
> - Remove clap of register value as .max_adj prevents any overflow.

Hi Niklas!

Sorry for being silent for a while, was traveling a bit. Your
explanation about addend in v3 is good enough and proofs that
there will be no overflow for the values provided.

Reviewed-by: Vadim Fedorenko <[email protected]>