Hi,
On Thu, Oct 3, 2024 at 10:23 AM Hal Feng hal.feng@starfivetech.com wrote:
On 01.10.24 01:56, Heinrich Schuchardt wrote: Another approach would be to build all device-trees into U-Boot and use the EEPROM information to select the correct one at runtime.
This approach is selected by Wandboard defconfig and other boards by specifying CONFIG_MULTI_DTB_FIT and CONFIG_OF_LIST. The choice of the device-tree is made in board_fit_config_name_match().
The advantage from the standpoint of a Linux distro would be that one distro image can be provided that will run on all JH7110 boards.
That is a good idea. I will try to do this after my five-day vacation. By the way, I wanna know whether jh7110-milkv-mars-cm.dts and jh7110-milkv-mars-cm-lite.dts are in the process of upstreaming? I don't see them in the kernel mainline.
Thanks for your suggestions.
Best regards, Hal
There is not any jh7110-milkv-mars-cm.dts and jh7110-milkv-mars-cmlite.dts patch for Linux kernel upstream yet.
Now may be a good time to do so, since Star64 was accepted and makes use of the common jh7110 dtsi that was introduced with devicetree of Milk-V Mars to Linux kernel. First this can go in U-Boot as the jh7110-milkv-mars.dts is good for Milk-V Mars CM and CM Lite, with addition of some GPIO assignments. This can be stubbed out by including jh7110-milkv-mars.dts until there are accepted upstream devicetree files for Mars CM and CM Lite. There are different GPIO assignments depending if it is U-Boot phase or Linux phase of the boot process; per the vendor sources. It is enough to pass a loaded jh7110-milkv-mars.dts to Linux on Mars CM and CM Lite hardware, if this GPIO assignment was done at U-Boot time and since then there is never any MMC reset while in Linux kernel:
https://github.com/milkv-mars/mars-buildroot-sdk/commit/880a249518f72ecf1e29...
https://github.com/milkv-mars/mars-buildroot-sdk/commit/042ea06598995db99ddb...
Much of the above diff listings can be ignored as already implemented or not needed, however, provided for reference what I am talking about for GPIO assignments 22 24 62 depending on the phase of boot process.
-E