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Discussion Starter · #1 ·
Experimenting with custom kernels I noticed occasional failures to boot - the kernel stalled up looking for root block device mmcblk0p2. Sounds similar to the problems people have reported with Debian.My problem was simply that the MMC card takes slightly longer to appear in the kernel layer than the kernel waits, sometimes.To fix, add 'rootdelay' in the kernel params in 'scriptcmd', ie setenv bootargs mem=112M root=/dev/mmcblk0p2 console=ttyS0,11520 lcdid=1 rootdelay=5(You might be able to get away with a lot less than 5 seconds.)This might explain the "Debian only works with CE installed" experience as well, it's possible something about scanning the NAND flash takes longer when it has CE installed and this lets the MMC catch up.I've updated the Debian scriptcmd that I was hosting on my website, you can grab it here:http://projectgus.com/files/eken/debian/scriptcmd(although that one only sets 109M of memory not 112M because I was using it to experiment with Android.)
 

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Reminds me of a similar problem which occurred with many ath wireless cards on cardbus (pcmcia) in Puppy. Wireless problems can be caused by lots of things, but in this case the cards just needed longer to initialize, and worked fine after a delay was added to the wireles scan routine.
 

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projectgus;28970]I said:
http://projectgus.com/files/eken/debian/scriptcmd[/url]
Question for ya, how did you generate that scriptcmd file ? I know you prolly used mkimage from the u-boot source, but what command line args did you use ? I've been trying to generate one that my tablet will recognize and for the life of me everytime mine fail and yours looks like it works.Any help would be appreciated!
 

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Discussion Starter · #5 ·
Command to convert 'cmd' to 'scriptcmd' is
mkimage -A arm -O linux -T script -C none -a 1 -e 0 -n "my awesome script" -d cmd scriptcmd
Also, if you need to read a scriptcmd minus the header then you can do
tail -c +73 scriptcmd
FWIW those two commands, plus other details, are in the README on the kernel git repository that I've started: projectgus's kernel_wm8505 at wm8505_2.6.29 - GitHub (You can read it all down the bottom of the page.)Also FWIW, if you really want to get involved then I strongly recommend hooking in a serial cable to your tablet. So many problems become obvious once you can look at the serial console.
 

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Discussion Starter · #7 ·
Ah well, it definitely happens with my custom-built kernels - they must still be booting with less hardware detection.Are you using the kernel from Abrasive's original Debian release? That might explain the discrepancy. I found I -had- to use the kernel from the official Eken 1.7.4 update.I'll take md5sums of those two kernels when I get home and post them.
 

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Discussion Starter · #8 ·
md5sums of binary kernels:Eken's official update: 4c22a500ea65a092d2a953a958aa5c39 uzImage.binabrasive's original debian kernel: 6d94b2c908b5980f436c452c2cfaedad uzImage.bin... I didn't keep a copy of the kernel that came in the release torrent, but it came up as different when diffed against the official Eken one.Custom kernel still a work in progress, although I pushed what I have to git just now. USB controllers are registering but not finding any USB devices (ie no wifi card.)
 

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Discussion Starter · #9 ·
PS I realised something else annoying using the linked scriptcmd: if you mount the ext2 partition from the SD on your computer and then boot from it, fsck freaks out due to "last mounted date in future." If console= is set, then it will prompt on the console for the root password to drop into single user mode. So don't use a scriptcmd with console= set (like the one above) with jacob's build, unless you actually have a serial console hooked in.(There's a fix you can do to the config files to make it not care about the last mounted date being in the future, btw.)
 

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Discussion Starter · #11 ·
projectgus;31506 said:
USB controllers are registering but not finding any USB devices (ie no wifi card.)
Still no progress here. In the custom kernel, no interrupts are coming in on interrupt 1 (as shown in /proc/interrupts), whereas in VIA's kernel they do.lspci -vv output is identical for both kernels, as is nearly everything else I can see/measure. All I can guess is that interrupt must be being masked off or something, or never enabled. Will keep looking into it.
 

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[quote name='projectgus;34055]Was it rootdelay' date=' or lcdid=1? I think maybe lcdid=1 (rootdelay can't hurt though.)[/QUOTE'] I successfully boot the debian in my flytouch:1. ProjectGus's scriptcmd2. official uzImage3. OLD extpart.tgzBut stll can't make wifi works.Hope this helps.
 

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I have a problem with booting debian. When device is powered and screen with android logo appears then screen is turning off and nothing more happens.According to partition manager, there 2 partition on sd card: fat and ext2 . It looks like all files successfully copied.Using Transcend SDHC class B 4 GB flash.
 
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