Diffstat (limited to 'wiki/src/blueprint/ARM_platforms/Acer_Chromebook_R_13_CB5-312T.mdwn')
1 files changed, 20 insertions, 0 deletions
diff --git a/wiki/src/blueprint/ARM_platforms/Acer_Chromebook_R_13_CB5-312T.mdwn b/wiki/src/blueprint/ARM_platforms/Acer_Chromebook_R_13_CB5-312T.mdwn
index 41f6501..d7d698e 100644
@@ -235,12 +235,16 @@ turned on:
console=tty1 printk.time=1 nosplash rootwait root=/dev/mmcblk0p2 ro rootfstype=ext4 lsm.module_locking=0 debug
console=tty0 printk.time=1 nosplash rootwait root=/dev/mmcblk0p2 ro rootfstype=ext4 lsm.module_locking=0 debug
+> anonym speaking: FWIW, I cannot reproduce (backlight remains off).
Now, `/dev/mmcblk0` is really the internal flash storage, and not my
micro-SD, as pointing `root=` to the ChromeOS root partition like this
does start ChromeOS:
console=tty1 printk.time=1 nosplash rootwait root=/dev/mmcblk0p5 ro rootfstype=ext4 lsm.module_locking=0 debug
+> anonym speaking: FWIW, I cannot reproduce this (nothing boots).
So to sum up, FWIW the "backlight turns on" behavior happens when…
`root=` is pointed to a ChromeOS kernel partition (that's definitely
not ext4). So, at least this kernel _is_ able to turn on backlight,
@@ -253,6 +257,14 @@ backlight doesn't turn on.
Conclusion: the official ChromeOS kernel lacks too much stuff that
a Debian userspace needs.
+> anonym speaking: I'm less sure about this conclusion; the Arch linux
+> one that works for us *is* a ChromeOS Kernel, with 13 patches
+> applied, none which looks relevant for boot issues (except
+> `0008-Downgrade-mmc1-speed.patch`, but it targets the .dtb file and
+> I tried rebuilding it with the patch => no joy).
+> TODO: retry with all the patches applied?
## Kernel approach 2 - Debian's kernel
XXX: retry with a more recent Debian kernel.
@@ -497,6 +509,9 @@ and the backlight remains off.
## Kernel approach 3 - custom Chrome OS kernel
+> anonym speaking: I tried these steps from the `chromeos-4.14` branch
+> with no success.
I've also tried building a custom ChromeOS kernel with added drivers
we might need. Instructions below are based on
@@ -564,6 +579,9 @@ The results below are about `ArchLinuxARM-2017.09-oak-rootfs.tar.gz`,
that's available at the time of writing in
+> anonym speaking: I have reproduced this with:
+> `ArchLinuxARM-2017.11-oak-rootfs.tar.gz` yay!
to install Arch Linux on a USB stick, and it booted flawlessly.
@@ -635,6 +653,8 @@ the partitioning and debootstrap steps have been done already.
## Kernel approach 5: custom Debian kernel
+> anonym speaking: I last tried linux-image-4.13.0-1-arm64
the Debian kernel with the `CONFIG_ARCH_MEDIATEK` and