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Thanks for the very helpful advice Heath. |
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I will definitely switch to the 2.6 kernel. As I said, it was a mistake. |
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I was using a machine that I set up long ago and forgot that it was |
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still running 2.4 (gotta fix that some day) Once I realized my mistake I |
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figured I'd continue anyway, in case I discovered anything else that |
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should be corrected. |
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As far as X is concerned, my application is for a headless embedded system. |
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To reduce writes to flash, I am mounting root read only, so the only |
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writes are during installation. Later I'll partition the CF card |
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to allow some writeable space for changing data and applications. |
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Speaking of fstab, there is a comment there: |
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>> # glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for |
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I presume that since we aren't using glibc, this doesn't hold? |
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I look forward to seeing any changes you make to your document, and I |
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will report back on changes I make to my procedure. |
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Michael |
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On Sat, 4 Jun 2005, Heath H Holcomb wrote: |
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> I would not use a 2.4 kernel unless your specific hardware is not stable on |
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> 2.6 or you need a custom application that only runs under 2.4. In either |
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> case these requirements are rare, and 2.6 is mostly the way to go. |
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> |
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> On my development system I have a hard drive with a full install of Gentoo |
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> 2005.0, and 1 GB partition setup so I can set up my embedded rootfs to test. |
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> I use the Gentoo install to mount a NFS shared directory from my development |
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> laptop (were I guild the embedded rootfs) and copy over the embedded rootfs |
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> to the 1 GB partition. I then modify my gurb.conf to give me the option of |
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> booting from the embedded rootfs on the 1 GB partition. This speeds |
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> development because getting the embedded rootfs done write the first time is |
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> almost impossible. |
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> |
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> The problem sounds like a kernel thing. Move to 2.6 and then see what |
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> happens. Remember lspci is your friend (to find out what hardware you have). |
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> |
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> Also remember Compact Flash cards have limited writes to the flash cells |
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> (usually measured in 100,000 to 300,000 writes); while hard drive have writes |
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> measured in hundreds of millions or billions. |
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> |
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> Your board uses the CLE266. If you want X (not using the generic vesa driver) |
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> you need to look at the Unichrome project. I subscribe to there mailing |
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> list. |
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> http://unichrome.sourceforge.net/ |
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> |
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> I'm also sending this response to the mailing list. |
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> |
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> I'm deploying my embedded rootfs to my test hard drive this weekend, so I'll |
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> have corrections and modifications to the how-to. By the end of the weekend |
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> the x86 how-to should be somewhat complete, at least at a very basic level. |
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> |
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> -- |
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> Heath Holcomb |
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> liquidcable |
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> liquidcable at bulah.com |
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> |
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> |
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> On Friday 03 June 2005 01:39 pm, you wrote: |
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>> Hi Heath, |
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>> |
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>> As you may recall, I was going to try to use your HOWTO to |
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>> create a gentoo embedded system on a CF card. I followed your |
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>> instructions up to Step 6, and then I do the following. I'm |
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>> not booting yet. Grub starts, but then seems to crash when |
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>> the kernel starts. I'm not sure because it's on the screen for |
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>> a split second and then my machine reboots. I suspect that I |
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>> made some mistakes in the kernel so I'm going to rebuild it, |
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>> and try again, but if you have any comments or thoughts on my |
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>> process I welcome them: |
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>> |
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>> My target SBC is a VIA EPIA ME-6000. I have my CF card as |
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>> my primary IDE device, and a CDROM drive as the secondary IDE device. |
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>> In the CDROM I'm using the Gentoo 2005.0 live cd. |
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>> |
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>> I'm sending this to you alone because I don't know if it's of |
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>> general enough interest. If you think it is, please feel free |
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>> to send it to the gentoo-embedded list, or tell me and I'll do it. |
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>> |
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>> The mistake I think I made in the kernel is that I built it on an old |
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>> gentoo system with a 2.4 kernel, so it created a 2.4 kernel, but your |
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>> instructions seem to be for a 2.6, so I'm going to repeat the process on |
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>> a newer gentoo system with a 2.6 kernel. |
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>> |
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>> Any comments are welcome |
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>> |
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>> Thanks again for writing your HOWTO |
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>> |
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>> Michael |
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>> |
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>> --- |
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>> |
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>> |
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>> 1. attach CF card as primary, CDROM as secondary |
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>> |
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>> 2. boot Gentoo live CD |
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>> |
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>> 3. fdisk /dev/hda |
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>> |
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>> boot: hda1 32M ext2 type 83 |
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>> root: hda2 rest ext2 type 83 |
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>> remember to make hda1 bootable |
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>> |
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>> 4. |
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>> mke2fs /dev/hda1 |
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>> mke2fs /dev/hda2 |
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>> |
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>> 5. mount the root and boot partitions |
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>> |
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>> mkdir /mnt/hda1 |
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>> mount -t ext2 /dev/hda1 /mnt/hda1 |
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>> mkdir /mnt/hda2 |
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>> mount -t ext2 /dev/hda2 /mnt/hda2 |
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>> |
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>> 6. copy the developed rootfs into the second partition on the CF card |
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>> |
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>> # on devel machine in chroot env |
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>> cp -r /embedded_rootfs /tmp # first copy from chroot env to outside |
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>> world |
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>> |
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>> # on devel machine in normal env |
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>> scp -r /opt/i586-gentoo-uclibc-linux/tmp/embedded_rootfs \ |
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>> root@192.168.0.22:/mnt/hda2 # IP address of my target SBC |
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>> FIXME do something about buzybox links |
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>> FIXME some problem with portage - same? |
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>> |
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>> 7. copy grub |
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>> |
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>> # on devel machine in normal env |
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>> scp /sbin/grub root@192.168.0.22:/mnt/hda2 |
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>> |
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>> 8. copy boot dir to /boot |
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>> |
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>> on target SBC |
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>> cp -r /mnt/hda2/boot/* /mnt/hda1 |
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>> |
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>> 8. install grub |
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>> |
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>> % /mnt/hda2/grub |
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>> |
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>> root (hd0,0) # grub's root i.e. boot |
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>> setup (hd0) |
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>> quit |
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>> |
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>> 9. configure grub.conf |
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>> |
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>> % nano -w /mnt/hda1/grub/grub.conf |
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>> |
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>> default 0 |
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>> timeout 10 |
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>> splashimage=(hd0,0)/grub/splash.xpm.gz |
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>> |
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>> title=Linux 2.6.x |
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>> root (hd0,0) |
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>> kernel /vmlinuz-2.6.x root=/dev/hda1 |
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>> |
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>> 10. fstab |
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>> |
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>> % nano -w /mnt/hda2/etc/fstab |
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>> |
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>> # <fs> <mountpoint> <type> <opts> <dump/pass> |
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>> none /proc proc defaults |
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>> 0 0 |
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>> |
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>> # glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for |
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>> # POSIX shared memory (shm_open, shm_unlink). |
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>> # (tmpfs is a dynamically expandable/shrinkable ramdisk, and will |
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>> # use almost no memory if not populated with files) |
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>> # Adding the following line to /etc/fstab should take care of this: |
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>> |
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>> none /dev/shm tmpfs defaults |
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>> 0 0 /dev/hda2 / ext2 ro 0 1 |
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>> |
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>> |
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>> 11. reboot |
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>> |
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>> sync # make sure writes are flushed to CF card |
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>> reboot |
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> |
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> -- |
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> gentoo-embedded@g.o mailing list |
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> |
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> |
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-- |
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