[PATCH v2 3/3] arm64: dts: renesas: r8a779g3: Describe split PCIe clock on V4H Sparrow Hawk

[Manivannan Sadhasivam]

On Wed, Jun 04, 2025 at 11:24:17AM +0200, Geert Uytterhoeven wrote:
> Hi Marek,
> 
> On Sat, 31 May 2025 at 00:55, Marek Vasut
> <marek.vasut+renesas at mailbox.org> wrote:
> > The V4H Sparrow Hawk board supplies PCIe controller input clock and PCIe
> > bus clock from separate outputs of Renesas 9FGV0441 clock generator chip.
> > Describe this split bus configuration in the board DT. The topology looks
> > as follows:
> >
> >  ____________                    _____________
> > | R-Car PCIe |                  | PCIe device |
> > |            |                  |             |
> > |    PCIe RX<|==================|>PCIe TX     |
> > |    PCIe TX<|==================|>PCIe RX     |
> > |            |                  |             |
> > |   PCIe CLK<|======..  ..======|>PCIe CLK    |
> > '------------'      ||  ||      '-------------'
> >                     ||  ||
> >  ____________       ||  ||
> > |  9FGV0441  |      ||  ||
> > |            |      ||  ||
> > |   CLK DIF0<|======''  ||
> > |   CLK DIF1<|==========''
> > |   CLK DIF2<|
> > |   CLK DIF3<|
> > '------------'
> >
> > Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
> 
> Thanks for your patch!
> 
> > V2: Use pciec0_rp/pciec1_rp phandles to refer to root port moved to core r8a779g0.dtsi
> 
> Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
> 
> I understand this has a hard dependency on [PATCH v2 1/3] (and on
> enabling CONFIG_PCI_PWRCTRL_SLOT), so I cannot apply this before that
> patch is upstream?
> 

TBH, this patch is describing the binding properly. So even though the driver
change is necessary to make the device functional, I don't see it as a hard
dependency. But since people care about functionality, if both driver and DTS
changes go into the same release, it should be fine IMO.

- Mani

-- 
மணிவண்ணன் சதாசிவம்