Searching for forum for help on dts devel for RK3568 board

[Erik Beck]

Hi Heiko,

You were right about the num-lanes = <1> for each pcie3!

Made that change to the dts and now both pcie3 bridges come up along
with the pcie2 bridge!

Next step is for me to figure out why the rtl8125-based chips attached
to each pcie3 bridge don't come up like the mt7921e "card" attached to
the pcie2 bridge.

Thank you for your help!

Erik

On Mon, 02 Jun 2025 09:10:12 +0200
Heiko Stübner <heiko at sntech.de> wrote:

> Hi Erik,
> 
> Am Sonntag, 1. Juni 2025, 23:52:14 Mitteleuropäische Sommerzeit
> schrieb Erik Beck:
> > Hi Heiko,
> > 
> > Thanks for the fast response!
> >
> > I'll give libera.chat a try.
> > 
> > I've been looking at the schematics, and they have helped somewhat,
> > but not getting me unstuck at the moment. The V2 should be pretty
> > similar to the V1, but there might be an important difference I'm
> > overlooking.
> > 
> > I'll give a look at those boards you mentioned. I've been using the
> > BPI-R2-Pro for inspiration. It has also helped, but there might be
> > something in the other boards relating to the PCIe bus that might
> > help.
> > 
> > I've been putting the work up onto github; current branch is:
> > https://github.com/TahomaSoft/openwrt-openwrt/tree/ExpDev-WIP7
> > 
> > Direct link to the DTS is:
> > https://github.com/TahomaSoft/openwrt-openwrt/blob/ExpDev-WIP7/target/linux/rockchip/patches-6.6/036-arm64-dts-rockchip-linkstar-minimal.patch
> >  
> 
> The the big neon sign on first glance is the missing lane-limitation.
> 
> pcie3x2 and pcie3x1 share their lanes, so depending on the board
> wiring you can either do pcie3x2 with 2 lanes, or both with 1 lane
> each.
> 
> See the
> 	num-lanes = <1>;
> lines in the devicetrees using both pcie controllers.
> 
> 
> Heiko
> 
> 
> > Thank you/Danke,
> > 
> > Erik
> > ~~~
> > On Sun, 01 Jun 2025 23:11:56 +0200
> > Heiko Stübner <heiko at sntech.de> wrote:
> >   
> > > Hi Erik,
> > > 
> > > Am Sonntag, 1. Juni 2025, 22:39:01 Mitteleuropäische Sommerzeit
> > > schrieb Erik Beck:  
> > > > I am working on initial support for an RK3568 board, the
> > > > LinkStar H68K-1421v1. I've made some progress, but can't get
> > > > past turning on one of the two PCIe3 Host bridges (pcie3x1
> > > > pcie at fe270000) without breaking the boot.
> > > > 
> > > > Is this the right location to ask for help? If not, where might
> > > > be? 
> > > 
> > > The mailinglist mostly has patches on it, so I don't really know
> > > if people are expecting non-patch mails.
> > > 
> > > If in doubt the #linux-rockchip channel on the libera.chat IRC
> > > network [0] might help more. (people in different timezones, so
> > > probably no immediate answers)
> > > 
> > > 
> > > 
> > > For the multi-pci case I guess you could start by looking at other
> > > rk3568 board doing similar things, like the Qnap-TS433 [1], Radxa
> > > E25 [2] or Nanopi-R5S [3].
> > > 
> > > Generally board designers often follow reference designs, so
> > > things might be similar.
> > > 
> > > Similarly, you might want to push your current in progress work on
> > > some github thing, so people can take a look.
> > > 
> > > 
> > > It also looks like the H68KV2 variant of the device has schematics
> > > available as linked from the bottom of [4], not sure how that
> > > relates to your device though.
> > > 
> > > 
> > > Heiko
> > > 
> > > 
> > > [0] https://libera.chat/
> > > [1]
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3568-qnap-ts433.dts
> > > [2]
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3568-radxa-e25.dts
> > > [3]
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3568-nanopi-r5s.dts
> > > [4]
> > > https://github.com/Seeed-Studio/wiki-documents/blob/docusaurus-version/docs/Network/RK_Devices/H68K_V2/H68KV2_install_system.md
> > > 
> > > 
> > > 
> > > _______________________________________________
> > > Linux-rockchip mailing list
> > > Linux-rockchip at lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/linux-rockchip  
> > 
> >   
> 
> 
> 
>