On Mon, 6 Aug 2018 at 19:39, Cédric Le Goater <c...@kaod.org> wrote: > > On 08/06/2018 05:25 AM, Joel Stanley wrote: > > Hello, > > > > I am attempting to boot evb-ast2500 in Qemu before flashing it to a > > system. It doesn't get past the DRAM step, due to getting stuck > > endlessly looping in some libfdt code. > > > > With some debugging turned on, I get this: > > > > OF: translating address: 0040781e > > OF: parent translation for: 00000000 > > OF: one level translation: 0040781e > > OF: parent translation for: 00000000 > > OF: one level translation: 0040781e > > OF: translating address: 00206e1e > > > > > > U-Boot 2018.09-rc1-00096-gbb694d4e898b-dirty (Aug 06 2018 - 12:27:22 +0930) > > > > Model: Aspeed BMC > > DRAM: OF: translating address: 00006e1e > > OF: translating address: 00026e1e > > OF: translating address: 0050781e > > OF: parent translation for: 00000000 > > OF: one level translation: 0050781e > > OF: parent translation for: 00000000 > > OF: one level translation: 0050781e > > Watchdog timer expired. > > > > And then the watchdog causes the system to reboot. The build is master > > as of gbb694d4e898b, with the addition of some #define DEBUG. > > > > I don't think this is a qemu issue. If it is, I can work on fixing > > qemu, but I need some help on understanding what u-boot is doing. > > The sdram driver in U-Boot uses the watchdog1 and the SCU power > reset register to reset the SDRAM controller. Our QEMU emulation > is not precise enough I think.
Thanks for the pointer. I was able to get u-boot to load to the prompt after some hacks to get rid of the watchdog requirement. It was a surprise to find out that the watchdog is used to reset the SDRAM controller! I have some patches to send to the qemu list that will allow it to run. Cheers, Joel _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot