Re: [PATCH net-next v3 09/10] dt-bindings: net: macb: add property indicating timer adjust mode
From: Krzysztof Kozlowski
Date: Wed Mar 11 2026 - 03:02:36 EST
On Tue, Mar 10, 2026 at 05:17:16PM +0000, Conor Dooley wrote:
> From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
>
> The GEM IP has two methods for modifying the ptp timer. The first of
> these, named "increment mode", relies on software controlling the timer
> by setting tsu_timer_incr and tsu_timer_incr_sub_nsec and performing
> once-off adjustments via the tsu_timer_adjust register. This is what the
> macb driver uses. The second mechanism, "timer adjust mode" uses the
> gem_tsu_inc_ctrl and gem_tsu_ms signals to control the timer. These
> modes are not intended to be used in parallel, but both can be possible
> on the same device and which mode is used cannot be determined from the
> compatible on all devices, because some users of the GEM IP are SoC
> FPGAs that permit configuring how the IP is wired up.
>
> Add a property to indicate that gem_tsu_inc_ctrl and gem_tsu_ms are wired
> up for timer adjust mode.
>
> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/net/cdns,macb.yaml | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
Best regards,
Krzysztof