I am designing a board with TK1.I want to use PCIe x4.The design guide says it is OK.But I would like to know if the software will sopport the design.
Is it easy to do the software change? I need the modify the u-boot or the kernel?
I use the case 4 described in the TK1 design guide as below:
lane 0 pcie#1_0
lane 1 pcie#0_3
lane 2 pcie#0_2
lane 3 pcie#0_1
lane 4 pcie#0_0
sata USBSS#1(USB 3.0 instead of USBSS1#)
Please check the file ‘/boot/extlinux/extlinux.conf’, search the pattern ‘lane_owner_info’. The original value should be ‘6’. Just change the value to ‘1’ and reboot the device. Then lane ownership should be configured as PCIe x4_x1.
The line most people will be interested in is the “APPEND” line, which is kernel command line argument (it’s possible other parameters were coded elsewhere, hence this “appends” and doesn’t “replace” the kernel command line). To know what the content of this line is you’d need to know what arguments that kernel accepts (which in turn depends on kernel version, what features are compiled in, and what features are loaded as a module). Note that this huge list of kernel arguments is still a single line…your editor may line wrap, but truly multiple lines would be incorrect.
Other lines are basically for selection of which LABEL to boot. Default L4T has only one label, but others can be added and interactively chosen via serial console during early boot.