On Tue, Oct 23, 2012 at 03:15:44AM +0000, Paul Walmsley wrote: > On Mon, 22 Oct 2012, Matt Porter wrote: > > > I've mentioned this a few times in various threads...no need to use > > appended DTB on a current U-Boot. Some of us are indeed booting this way > > with the DTB properly passed separately from the bootloader and chosen > > filled out by the bootloader. And yes, am335x_evm_config applies to all > > AM33xx TI EVMs and the BeagleBone board. There's an EEPROM onboard all > > that is used to determine what board is present so a single > > MLO/u-boot.img can be used. > > As Kevin mentioned earlier, this is unfortunately not true for those of us > with earlier BeagleBoards: > > http://marc.info/?l=linux-omap&m=135094296931913&w=2 Yes, we spoke about this a bit. > Do you know what the minimum board revision is that you all are > supporting in U-boot? It's not so much a revision as it is getting the right contents in the EEPROM. As it's a community board, it's generally only supported over at beagleboard@xxxxxxxxxxxxxxxx. Jason Kridner recommends posting support questions there (like why isn't my A2 supported in U-Boot?). If there isn't some solution suggested there for updating the A2 I would contact him directly. I have an A1 Bone here that also doesn't work with mainline U-Boot even after configuring the EEPROM. You can try this procedure if you want to write the proper contents in, an A2 may work but for some reason there's no available history on Bone revisions prior to A3. I vaguely recall a lot of chatter around the phy and so forth in the A1 to A2 timeframe so it's entirely possible that your A2 will work with just the eeprom contents programmed. Without it, it's guaranteed to fail as the pin muxing is tied to detecting the board this way. Also, you may need to change <offset>.1 in the below example to <offset>.2 for your eeprom i/o to work as A2 may require an address length of 2. -Matt U-Boot 2012.10-00286-gfe27b3b (Oct 22 2012 - 16:40:21) I2C: ready DRAM: 256 MiB WARNING: Caches not enabled MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1 Using default environment Net: PHY reset timed out cpsw Hit any key to stop autoboot: 0 U-Boot# i2c dev 0 Setting bus to 0 U-Boot# i2c md 50 0.1 0000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ U-Boot# mm.b 84000000 84000000: 55 ? aa 84000001: 51 ? 55 84000002: 16 ? 33 84000003: 00 ? ee 84000004: 40 ? 41 84000005: 94 ? 33 84000006: 28 ? 33 84000007: 41 ? 35 84000008: 11 ? 42 84000009: 55 ? 4f 8400000a: 80 ? 4e 8400000b: 8e ? 45 8400000c: 03 ? 30 8400000d: 5d ? 30 8400000e: 44 ? 41 8400000f: a0 ? 32 84000010: 46 ? . U-Boot# i2c write 84000000 50 0.1 10 U-Boot# i2c md 50 0.1 10 0000: aa 55 33 ee 41 33 33 35 42 4f 4e 45 30 30 41 32 .U3.A335BONE00A2 U-Boot# -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
