Draft: Removed symlinks to the kernel, initrd, devtree; Device trees for whle-ls1-sdk kernel

Symlinks obsoleted by the use of u-boot-menu

Scope

To get rid of

/boot/board.dtb
/boot/initrd.img
/boot/initrd.img.old
/boot/vmlinuz
/boot/vmlinuz.old

Tests

Tested on WHLE-LS1026A.

Initial state

/boot contents at first login:

root@whle-ls1046a:~# ls /boot

System.map-6.5.6-whle-ls1-g88fc5c2e4673
config-6.5.6-whle-ls1-g88fc5c2e4673
extlinux
initrd.img-6.5.6-whle-ls1-g88fc5c2e4673
vmlinuz-6.5.6-whle-ls1-g88fc5c2e4673

State after linux package installation

1. SDK kernel

   root@whle-ls1046a:~# apt install linux-image-6.1.56-whle-ls1-sdk-g5f6cdda7d834 
   …
   root@whle-ls1046a:~# ls /boot
   
   System.map-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   System.map-6.5.6-whle-ls1-g88fc5c2e4673
   config-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   config-6.5.6-whle-ls1-g88fc5c2e4673
   extlinux
   initrd.img-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   initrd.img-6.5.6-whle-ls1-g88fc5c2e4673
   vmlinuz-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   vmlinuz-6.5.6-whle-ls1-g88fc5c2e4673

2. Regular kernel

   root@whle-ls1046a:~# apt install linux-image-6.5.6-whle-ls1-gcb9fc46d1a8f
   …
   root@whle-ls1046a:~# ls -lh /boot
   
   -rw-r--r-- 1 root root 3.1M May 13 22:22 System.map-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   -rw-r--r-- 1 root root 3.0M Apr 22 19:53 System.map-6.5.6-whle-ls1-g88fc5c2e4673
   -rw-r--r-- 1 root root 3.0M Jan  4 14:56 System.map-6.5.6-whle-ls1-gcb9fc46d1a8f
   -rw-r--r-- 1 root root 164K May 13 22:22 config-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   -rw-r--r-- 1 root root 164K Apr 22 19:53 config-6.5.6-whle-ls1-g88fc5c2e4673
   -rw-r--r-- 1 root root 164K Jan  4 14:56 config-6.5.6-whle-ls1-gcb9fc46d1a8f
   drwxr-xr-x 2 root root 4.0K May 15 22:59 extlinux
   -rw-r--r-- 1 root root  11M May 15 22:44 initrd.img-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   -rw-r--r-- 1 root root 9.8M May 15 21:07 initrd.img-6.5.6-whle-ls1-g88fc5c2e4673
   -rw-r--r-- 1 root root  11M May 15 22:59 initrd.img-6.5.6-whle-ls1-gcb9fc46d1a8f
   -rw-r--r-- 1 root root 8.0M May 13 22:22 vmlinuz-6.1.56-whle-ls1-sdk-g5f6cdda7d834
   -rw-r--r-- 1 root root 7.8M Apr 22 19:53 vmlinuz-6.5.6-whle-ls1-g88fc5c2e4673
   -rw-r--r-- 1 root root 7.8M Jan  4 14:56 vmlinuz-6.5.6-whle-ls1-gcb9fc46d1a8f

Booting with the newly installed kernels: OK

Device trees for the SDK kernel

The whle-ls1-sdk kernel variant requires different device tree than the regular one /usr/lib/linux-image-‹ver›/freescale/fsl-ls1046a-whle.dtb to boot properly - the usdpaa devtrees ("user space DPAA"). Two possibilities:

• Static usdpaa device tree: Assigns the network interface to either kernel or DPDK. Easier to control the queues with FMC. This solution was used in the whales demo. There are 2⁶ = 64 possible device trees, assigning each interface to a different driver. Of these 2 were provided in linux@32855dc4:
  • fsl-ls1046a-whle-usdpaa-000000.dtb: all NICs assigned to kernel
  • fsl-ls1046a-whle-usdpaa-000011.dtb: all 1G NICs assigned to kernel, 10G NICs assigned to DPDK.
• Shared usdpaa device tree: Allows for sharing the network interface between kernel and DPDK. Harder to control the queues with FMC though more convenient for the user. To be accounted for in the next iteration, after full incorporation of the whales demo into CE repositories.

The change in ubuntu-build detects the use of the SDK kernel variant and modifies the /usr/lib/linux-image-‹ver›/fsl-ls1046a-whle.dtb symlink to point to the usdpaa device tree. Example:

root@whle-ls1046a:~# ls -lh  /usr/lib/linux-image-6.1.56-whle-ls1-sdk-g5f6cdda7d834/
drwxr-xr-x 2 root root 4.0K May 15 22:44 freescale
lrwxrwxrwx 1 root root   99 May 15 22:44 fsl-ls1046a-whle.dtb -> /usr/lib/linux-image-6.1.56-whle-ls1-sdk-g5f6cdda7d834/freescale/fsl-ls1046a-whle-usdpaa-000000.dtb
lrwxrwxrwx 1 root root   85 May 15 22:44 fsl-ls1088a-whle.dtb -> /usr/lib/linux-image-6.1.56-whle-ls1-sdk-g5f6cdda7d834/freescale/fsl-ls1088a-whle.dtb

The regular version remains as before

root@whle-ls1046a:~# ls -lh  /usr/lib/linux-image-6.1.56-whle-ls1-g5f6cdda7d834/
drwxr-xr-x 2 root root 4.0K May 15 23:21 freescale
lrwxrwxrwx 1 root root   81 May 15 23:21 fsl-ls1046a-whle.dtb -> /usr/lib/linux-image-6.1.56-whle-ls1-g5f6cdda7d834/freescale/fsl-ls1046a-whle.dtb
lrwxrwxrwx 1 root root   81 May 15 23:21 fsl-ls1088a-whle.dtb -> /usr/lib/linux-image-6.1.56-whle-ls1-g5f6cdda7d834/freescale/fsl-ls1088a-whle.dtb