[PATCH v1] phy: rockchip-snps-pcie3:phy: Configure clkreq_n and PowerDown for all lanes
Anand Moon
linux.amoon at gmail.com
Thu Apr 9 06:30:32 PDT 2026
Hi Niklas,
Thanks for your review comments.
On Thu, 9 Apr 2026 at 15:19, Niklas Cassel <cassel at kernel.org> wrote:
>
> +Shawn
>
> Hello Anand,
>
> On Thu, Apr 09, 2026 at 10:19:30AM +0530, Anand Moon wrote:
> > During the rk3588_p3phy_init sequence, the driver now explicitly
>
> Please use imperative mood, active voice.
>
>
> > configures each lane's CON0 register to ensure
> > - PIPE 4.3 Compliance: clkreq_n (bit 6) is forced low (asserted) to meet
> > sideband signal requirements.
> > - Active Power State: PowerDown[3:0] (bits 11:8) is set to P0
> > (Normal Operational State) to ensure the PHY is fully powered and ready
> > for link training.
> >
> > These changes ensure that all lanes are consistently transitioned from
> > reset into a known-good operational state, preventing undefined behavior
> > and ensuring the PHY is ready for high-speed data transmission.
>
Ok, I will update this.I f
> First describe the problem, then describe how you fix it.
I was investigating the PCIE30X4_CLKREQn issue highlighted by Shawn Lin,
analyzing the RK3588 TRM clock request configurations (page 878)
[1] https://lore.kernel.org/all/77f0d3c2-649f-770d-1636-6fd52f3b5f5e@rock-chips.com/
Looking into the power management state on Intel’s PCI Express Power Management
documentation, which defines states such as P0, P0s, P1, P1.1, P1.2, and P2
Understanding this mapping is for interpreting the behavior of lane-specific
clock requests, so initialize this to the P0 state..
[2] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/phy-interface-pci-express-sata-usb30-architectures-3.1.pdf
>
>
> Kind regards,
> Niklas
Thanks
-Anand
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