by WanderingHarbinger » Thu Apr 21, 2016 3:59 pm
I am happy to see there is someone else still interested in this awesome ac100/dynabook from toshiba.
I also have their AT100 tablet which is tegra 2 too, one of the few tablets with removable/replaceable batteries.
To answer your queries:
$this->bbcode_second_pass_quote('', 'W')hat I wonder now is if it is possible to nuke all the other partitions and make the whole storage into a single partition to boot the TrimSlice rootfs on the AC100? I never use the CM11 install, and it basically just sits there taking place + all the other stupid partitions.
Yes, this is what I am using right now with the trimslice rootfs. You will always have three partitions remaining. Two mmcblk#boot# and one mmcblk#p#. I created a single gpt partition used uboot commands.
First two partitions are your bootloader+BCT( cant remember the order) and/or partition table(PT). You just need to know where those partitions end on your mmc device and exclude them from the system partition. The kernel will automatically map the boot# parts, it did for me. I think you are safe if you just dont touch the first 2048 kilobytes of the mmc device, make it 3MB imo ( in case of something great later, like coreboot bootloader that can deliver a uboot or fastboot payloads )
My uboot is a custom build that adds edid support for any resolution panels as I updated mine to 1366x768. Problem is I haven't merged in the keyboard driver ( use a usb keyboard ) from an earlier version of uboot someone created since I dont understand the new driver model yet. It would be easier to backport my edid changes though as the codebase for that looks the same.
Also, you will want to check this out:
https://github.com/ehalls/cbootimage-configshttps://github.com/ehalls/u-boot-ac100, uboot with edid tegra2 support. Not user friendly, only use if you are ready to upgrade the panel.
and tegra stuff at
https://github.com/NVIDIAand community ac100 stuff at:
https://github.com/ac100-ru/sosboot , based on buildroot .. you can just do this yourself
Basically you build uboot for paz00 ( the ac100 motherboard codename) and flash it using cbootimage-configs. Just make sure to set it up right using
https://github.com/nvidia/tegra-uboot-flasher-scripts I use a custom kernel .. which isnt necessary( stock trimslice zImage is fine as long as your uboot is configured to find the boot.scr/bootscript) but I was trying to get overclocking working on the 4.4/4.5 kernels. OC isnt there yet cause there is a hard software limit somewhere unlike the older code from 2.6-3.10 and I can't find something that correlates to configuration of the dynamic voltage frequency scaling. I need this to overvolt for a 1.4ghz or even try a 1.9Ghz overclock if I wanted to try them using a heatsink.
Notes:
For performance, adjust the ulimits thread size to something like 256k instead of 8Mb.
Had wifi issue with gentoo, make sure to try different firmwares the card under lib/firmware
In uboot, you can manually boot (my addressing could be too spaced out):
ext2load mmc 0:1 0x1000000 /boot/zImage
ext2load mmc 0:1 0x2200000 /boot/uInitrd ( this can just be an empty base rootfs, since you might have initramfs builtin )
ext2load mmc 0:1 0x3000000 /boot/dtb/tegra20-paz00.dtb
bootz 0x1000000 0x2200000 0x3000000
or when the dtb is combined with your zImage, its a simple append to the end of a "fresh" zImage
bootz 0x1000000 0x2200000
Hope this clarifies a few things, I may be porting coreboot and chromium os to this device since it uses a gentoo backend which will make it easier to keep an optimized image (size and speed). Lots of work, less than full time.