Disable SSC for Xavier NX PCIex4

[yahoo2016]

We need to disable SCC for a PCIe camera, I found the following thread:
Tegra NX PCIe Reference Clock Design - Jetson & Embedded Systems / Jetson Xavier NX - NVIDIA Developer Forums
but could not find the dtsi file “tegra194-bpmp-p2888-uphy.dtsi” from Jetson SDK or kernel source.
Where can I find the dtsi file? Is there instructions of building the (bootloader?) dtb file?
I have built kernel Image and DTBs but not bootloader DTB.
Thanks in advance.

[vidyas]

DT source file can be found at ./platform/bpmp-t19x/include/parts/uphy/tegra194-bpmp-p2888-uphy.dtsi location whereas the equivalent DTB file can be found at Linux_for_Tegra/bootloader/t186ref location (which can be recompiled back to a dtsi file, make required modifications and then compile it back to DTB file)

[yahoo2016]

How do I find “clock id” of PCIex4 for different L4T versions if I add the section and recompile DTB? I still can’t find the "tegra194-bpmp-p2888-uphy.dtsi " file, please provide more details about where to find it and how to build boot loader dtb from dtsi.

[Manikanta]

Hi,

Please follow step to step from comment to disable SSC in Jetson NX devkit M.2 KeyM x4 slot.

Tegra NX PCIe Reference Clock Design

For anyone that needs to do this on their NX kits (or similar): Vidyas patches are from a git repo we do not have access to. So what you need to do: Pay attention to the #include directive in the patch. While I cannot find <mach-t194/clk-t194.h>, I can find the clock id - TEGRA194_CLK_PLLNVHS by just grepping through everything after doing source_sync.sh. Use the clock ID from there and mind that you use the same clock ID that is for the L4T version you are using. E.g. source_sync.sh -d <YOUR…

Thanks,
Manikanta