Re: [PATCH 00/11] arm64: dts: renesas: Specify ethernet PHY reset timings

[Marek Vasut]

On 5/22/26 3:18 PM, Geert Uytterhoeven wrote:

Hello Geert,

> On Tue, 5 May 2026 at 05:43, Marek Vasut
> <marek.vasut+renesas@xxxxxxxxxxx> wrote:
> > This is the same patch for various boards, details are below.
> > The discussion that prompted this patchset is at [0].
>
> Thanks for your series!
>
> > The KSZ9031RNX reference manual [1] DS00002096H page 60 FIGURE 7-7:
>
> DS00002117K page 62 FIGURE 7-5
>
> (and page 74 on the older document I had ;-)
>
> > POWER-UP/POWER-DOWN/RESET TIMING Note 2 states, that after the
> > de-assertion of reset, wait a minimum of 100 us before starting
> > programming on the MIIM (MDC/MDIO) interface. Set DT property
> > reset-deassert-us to three times that, 300 us, to provide ample
> > time between reset deassertion and MDIO access.
> >
> > The KSZ9031RNX reference manual [1] DS00002096H page 60 TABLE 7-7:
> > POWER-UP/POWER-DOWN/RESET TIMING PARAMETERS row tSR Stable supply
>
> page 62 TABLE 7-4
>
> > voltages to de-assertion of reset is at minimum 10 ms. Set DT
> > property reset-assert-us to 10ms because the KSZ9031RNX RM does
> > not explicitly spell out how long the reset has to be asserted,
> > but this at least covers the worst case scenario.
> >
> > The Gray Hawk patch in this series depends on [2].
> >
> > [0] https://lore.kernel.org/all/CAMuHMdXJvrsXitGagqZJ_STdTTh_s1cBAKf6+esihaVWjfn40g@xxxxxxxxxxxxxx/
> > [1] https://ww1.microchip.com/downloads/aemDocuments/documents/UNG/ProductDocuments/DataSheets/KSZ9031MNX-Data-Sheet-DS00002096.pdf
>
> This link leads to the KSZ9031MNX part. Correct link is:
>
> https://ww1.microchip.com/downloads/aemDocuments/documents/UNG/ProductDocuments/DataSheets/KSZ9031RNX-Data-Sheet-DS00002117.pdf
>
> > [2] https://lore.kernel.org/all/20260504225428.114959-1-marek.vasut+renesas@xxxxxxxxxxx/
>
> Shall I do the big search-and-replace while applying?
Yes please. Thank you for spotting this.