[U-Boot] da850evm: u-boot does not start without UBL since commit f1d2b313c9eb6808d30c16a9eb5251240452a56c

[Ben Gardiner]

Hello Christian,

On Wed, Jun 1, 2011 at 12:58 PM, Christian Riesch
<christian.riesch at omicron.at> wrote:
> I have tried to run recent versions of u-boot on the da850evm (AM1808
> eXperimenter's Kit) board. Using Texas Instrument's User Boot Loader (UBL)
> to start u-boot (the default configuration for the EVM) everything works
> fine. However, if I try to get rid of this UBL (I don't need to voltage
> scaling features that it provides, so it's useless for me, just additional
> code that needs maintenance), I run into trouble.
>
> Instead of using UBL, I use AIS [1] to configure PLLs and mDDR timings.
> My AIS script is generated by the HexAIS tool [2], the settings in the
> input file of HexAIS are
>
> [General]
> busWidth=8
> BootMode=SPIMASTER
> crcCheckType=NO_CRC
> [PLLANDCLOCKCONFIG]
> PLL0CFG0 = 0x00180001
> PLL0CFG1 = 0x00000205
> PERIPHCLKCFG = 0x0000000a
> [EMIF3DDR]
> PLL1CFG0 = 0x15010001
> PLL1CFG1 = 0x00000002
> DDRPHYC1R = 0x000000C4
> SDCR = 0x0A034622
> SDTIMR = 0x184929C8
> SDTIMR2 = 0xB80FC700
> SDRCR = 0x00000406
> CLK2XSRC = 0x00000000
> [INPUTFILE]
> FILENAME=u-boot.bin
> LOADADDRESS=0xC1080000
> ENTRYPOINTADDRESS=0xC1080000
>
> While this configuration works fine for older versions of u-boot (like
> v2009.11), it fails with recent u-boot versions (no sign of life on the
> serial port). I have bisected down to the commits from
>
> commit f1d2b313c9eb6808d30c16a9eb5251240452a56c
> ARM: add relocation support
>
> to
>
> commit ab86f72c354f9b2572340f72b74ca0a258c451bd
> ARM: implement relocation for ARM926
>
> Since these commits u-boot does not boot without the help of UBL. So I
> guess these commits require some additional initialization that is done
> by UBL, but not by my AIS.
>
> I have tried to figure out what I am missing, but without success so
> far.
>
> Any ideas what I could try to get it running?

Last I heard about this [1] the AIS signer was unable to handle the
dynamic elf format resulting from the introduction of arm relocation.

If that particular problem is no more, then I  imagine that UBL would
have been doing pinmux for serial port among other things. If you are
able to debug with JTAG then you might be able to inspect where the
execution goes wrong; otherwise maybe removing as much peripheral
access from u-boot as is possible and adding it back incrementally
could reveal what UBL setup is missing.

Best Regards,
Ben Gardiner

[1] http://article.gmane.org/gmane.comp.boot-loaders.u-boot/95097

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