Boot the SmartQ from SD card

 

http://www.jiongtang.com/blog/html/smartq5/boot-the-smartq-5-from-sd-card.html

 

roberto from spain has made a modified Qi bootloader for the SmartQ 5 MID that can boot from the external SD card, as a convenient way of developping or testing OS, or for system rescue purposes in case of internal flash corruption. This is the bootloader operation:

• Search for a valid ext2/ext3 partition in the SD card (4 primary partitions).
• If the file /boot/noboot-SDMK6410 exists, it will skip that partition and try the next one. Useful for disabling partitions temporary.
• Load and run the kernel image from file /boot/linux-SMDK6410.bin (if it exists). It should be on uImage or zImage formats.
• The optional file /boot/append-SMDK6410 can be used to specify additional kernel arguments.

The SmartQ Qi bootloader is written to the end of the SD card. Create partitions to suit your preferences, make at least one ext2/ext3 partition to install the root filesystem and optionally a swap partition, but always remember to reserve 1 MiB of free, unpartitioned space at the end of the SD card . To be precise, at least the latest 1042 blocks (512 bytes each) must be reserved.

The precompiled bootloader and a kernel, installation script and source code are here:

http://zenvoid.org/software/qi-smartq

Look at the script install-smartq-qi.sh in order to make a bootable SD card:

./install-smartq-qi.sh /dev/SD_CARD_DEVICE qi-smartq-20090603.bin

To boot from the SD card, keep the “move” (also known as fullscreen) button pressed and then press the “power” button.

• Yellow LED: bootloader running, trying to locate and loading a kernel image.
• Green LED: Linux kernel loaded and running.

Update:

This release has some fixes and helpful changes for debugging. But remember that it is experimental and unsupported code, so be careful. Source code and binaries are here:

http://zenvoid.org/software/qi-smartq

The kernel is also updated. It is recommended to use the kernel and modules included in that directory as it has been modified to show Linux console messages on the screen (very useful for locating and fixing problems). To install the bootloader, follow the instructions of the previous release .

When booting, it shows a very short red light, followed by a short yellow, followed by green light. If green light is reached, it means that the bootloader has finished its job and Linux is booting. If you are using my modified kernel, you should see the boot messages from this point. This is the meaning of the LED lights:

• Red LED: First stage – bootloader is loading itself into memory.
• Yellow LED: Second stage – bootloader running, trying to locate and loading a kernel image.
• Green LED: Linux kernel loaded and running.

• Blinking yellow LED: A critical error while reading from the SD card.
• Blinking green LED: No kernel found.

Blinking red LED should mean that the battery is too low, but it is not implemented yet.

Photos of the boot messages and Mer distribution running from SD card:

roberto is a developer of Mer ,if you are interested in cooperating with the Mer project please join to the #mer channel at irc.freenode.net.