On 06/02/15 13:37, Vagrant Cascadian wrote:
I'm able to get both openrd_base and openrd_ultimate to build (no idea if it boots) by disabling MMC support with u-boot 2015.04. But then, it sounds like you're actively looking for MMC support... Another option might be to move where the stored u-boot environment is to allow for a larger u-boot binary, but this breaks backwards compatibility; this may also be an issue for the SheevaPlug and other marvell platforms: https://lists.debian.org/debian-arm/2015/04/msg00023.html https://bugs.debian.org/781874 https://bugs.debian.org/781873 There isn't much traction in upstream u-boot on this, and I suspect u-boot is basically broken on sheevaplug, guruplug and openrd_ultimate in jessie, stretch and sid... With no activity upstream, I'm hesitant to just break backwards compatibility by moving the environment; it might be better to drop support. The choices seem to be between not including features, or breaking backwards compatibility with the environment location, and I'd like to move in whichever direction gets into upstream u-boot on this, which currently is neither... live well, vagrant
Is there a pre-built (however old) U-Boot I can use that supports MMC?I'd really like to be able to use all three sources for booting: MMC (SD card), USB (USB stick or USB hard drive) and eSATA (hard drive).
I'm using the box for experimenting, so as much flexibility as possible is highly desirable...
Here's an interesting thought... I don't know how much effort it would require, or even if it would work at all, but:
Maybe a chain-loader approach; A totally minimal stripped down U-boot lives in the usual place in ROM. It loads a much more robust U-Boot from the SD card (which can be as big as 32GB!) Then the big U-boot is finally used to boot the Linux system from whatever system residency device you chose -- eSATA, USB-stick, USB hard drive, or even a different partition on the SD card...
All the minimal U-boot in ROM needs to do is load from MMC, so, once installed, it can be considered static -- "part of the hardware". The "real" U-boot lives on the SD card, so (as if by magic) the box becomes "un-brickable". I can keep an SD card with a working U-boot on it in reserve if I mess up using an experimental version for testing.
What do you think? Enjoy! Rick