ALARM on Samsung ARM Chromebook

[jacobopantoja]

I've started a Wiki page at the ArchWiki for this Chromebook.

https://wiki.archlinux.org/index.php/Samsung_Chromebook_(ARM)

I will try to add all the stuff already discussed in this thread. Any help is more than welcome.

EDIT: BTW, As far as I have seen, the read-only protection is provided by the sticker, *not* by the screw. Could someone confirm?

[ivanjan]

I confirm, It is only the sticker.
When I cleaned up around the screw, it allowed me to flash nv-u-boot.
It probably some residual material from the sticker that was still creating the contact.

[krrishnarraj]

This looks great. Did you try booting stock chrome OS from the new firmware?
Can some dedicate a page in http://archlinuxarm.org/platforms/armv7 ... chromebook explaining in detail how to flash new nv firmware without breaking the device
http://www.chromium.org/chromium-os/u-b ... chromebook lists 2 prebuilt nv-uboot firmware images. The second image says simple frame buffer.. what exactly is this?

[ivanjan]

krrishnarraj,

I was following the instructions from strata.
Ubuntu was installed previously on the internal eMMC, but when i flashed using nv-u-boot file provided by strata, and rebooted, ubuntu was gone, and chromeos is back. So yes I was able to boot into chrome os.

Strata's instructions are good, except I used google.flashrom instead flashrom only, not sure if it matters.

[doragasu1]

Has anyone in here replaced the default SSD drive with a bigger one? I have been reading a lot, and it looks like ChromeOS is really picky about SSD drives. Do these problems with SSD drives happen also with ALARM?

[doragasu1]

OK, I have been toying a bit with ALARM installed in a chroot, and I definitely love it. Now I would like to get rid of ChromeOS, and of the annoying Ctrl+D when booting. I'd like to install ALARM to the internal eMMC drive. I have been reading for a while, but I'm a bit confused.

What I know (please correct if I'm wrong):

1.- I have to open the device and remove the flash write protection ring.
2.- I have to boot ALARM from the SD (in developer mode) and flash nv-U-Boot (hopefully the one posted by strata will work).

What I'm not sure of:

1.- Reading instructions from strata, it's clear you can boot from the internal eMMC. Once finished following his instructions, it looks like you can boot without the need of a SD card, but I'm not 100% sure.
2.- How is the stability of ALARM using this mode? I know that due to driver issues, video performance is poor (bye bye YouTube), but what about the hardware? Do sound, HDMI output, brightness control, battery readings, etc. work?
3.- I was impressed by the loading speed of ChromeOS. How much time takes ALARM to boot from the internal eMMC?

Edit: Cleaned the post a bit after discovering that the device does not have an internal mSSD (as I thought was the case). It has eMMC memory soldered to the board. Too bad I will not be able to upgrade it

[doragasu1]

I have started trying to install alarm in the internal eMMC. I opened the device, removed the write-protect and successfully flashed nv-U-boot. But I have a problem. I have to write the kernel and modules to the SD, and I don't have them. Since I flashed nv-U-boot, I cannot (or at least I don't know how to) boot ChromeOS in developer mode, so I can't get the files. Is there a way to boot ChromeOS in developer mode using nv-U-boot? Or are these files available for download?

[doragasu1]

OK, I have downloaded kernel and modules from here, and did these steps:

1.- I used gparted to create a new GPT partition table in a 16 GB SD card, created a new 16 MiB EXT2 partition (leaving 4 free MiB before), and an new JFS partition with the remaining space.

2.- I put the kernel (renamed to vmlinux.uimg) in the 16 MiB EXT2 partition, and the modules and rootfs in the JFS partition. Modules are under /usr/lib/modules/3.4.0-5-chromebook. I have noticed the arch rootfs comes with its own modules under /var/lib/modules/3.4.0. I suppose I could delete them, but I left them.

3.- Inserted the SD card in the chromebook, entered nv-U-boot and issued the commands pointed by strata. The kernel loads, but after a second or two, I get a kernel panic: "VFS: Cannot open root device "mmcblk1p2" or unknown-block (179,50): error -19". mmcblk1p2 is listed though in the available partitions shown before the error message...

I don't know if the problem is in the SD card partition table. When I issue the "mmc dev 1" command, I get the following error:

$this->bbcode_second_pass_code('', 'ERROR: v7_dcache_inval_range - stop address is not aligned - 0xbda3c4c8
mmc_init_err 0, time 21666
mmc1 is current device')

But I ignored it because the ext2load command completes without errors...

Could anyone please elaborate on how to correctly create the partitions using cgdisk?

[doragasu1]

I'm slowly progressing, but again I have hit a wall. I have repeated the SD preparation process, but I have formatted the second partition using ext4 filesystem instead of JFS. Now I can boot arch, but I cannot get a lot of hardware (anything that needs modules, I guess) to work.

wifi-menu returns: " > No such interface: mlan0"
lsusb returns: "unable to initialize libusb: -99"
And of course lsmod returns no loaded modules.

To me it looks like I have not matching kernel and modules. ¿Could anyone *please* upload working kernel and modules??? I tried extracting the kernel from the alarm rootfs posted here, but I could not mount the two first 16 MiB partitions containing the kernel. It looks like if they were damaged.

[doragasu1]

FINALLY I could get a working kernel+modules package. Thanks a lot to @xenoxaos for pointing me to them

Hardware is working fine. Time to install a full system to then dump it to the eMMC