[U-Boot] [PATCH 0/20] tegra: Expand Nyan-big support

[Simon Glass]

Hi Sjoerd,

On 30 March 2015 at 02:14, Sjoerd Simons <sjoerd.simons at collabora.co.uk> wrote:
> On Fri, 2015-02-27 at 22:11 -0700, Simon Glass wrote:
>> Hi Sjoerd,
>>
>> On 25 February 2015 at 17:12, Sjoerd Simons
>> <sjoerd.simons at collabora.co.uk> wrote:
>> > Hey Simon,
>> >
>> > Incidentally i got acces to a Nyan big and wanted to start testing
>> > u-boot on it. Unfortunately putting a uImage in a vboot signed blob to
>> > chainload it from the primary bootloader like on the exynos based
>> > chromebooks seemed not to work.
>> >
>> > Do you have any good pointers how to use u-boot on nyan? (Ideally
>> > without having to re-flash coreboot, as i would like to create images
>> > people can easily test on a vanilla chromebook)
>>
>> No I don't sorry. I suppose in dev mode it should boot a signed image
>> so if you put U-Boot in a FIT as with snow/pit it should work. But I
>> don't have instructions...if you figure it out it would be good to put
>> this info somewhere.
>
> Finally got time to play a bit with this. On the snow/peach boards the
> approach is to put u-boot in a legacy u-boot image (not a FIT image),
> which has the nice side-effect of re-locating u-boot before jumping to
> it.
>
> Unfortunately the depthcharge on the nyan boards appears not to support
> legacy images, only FIT images, which don't get relocated before jumping
> into the kernel blob. Long story short, on the nyan boards the FIT image
> gets loaded at 0x81000000 and the FIT images i created put the u-boot
> blob at an offset of 0xCC. After re-configuring CONFIG_SYS_TEXT_BASE to
> match i got u-boot starting \o/ ;)
>
> Unfortunately the board seems to hard hang when it tries to enable/use
> the data cache. Enabling CONFIG_SYS_DCACHE_OFF makes it get to the
> u-boot prompt. Unfortunately neither MMC (didn't detect card) nor USB
> (failed to get descriptor from my usb network dongle) worked so i
> couldn't try booting a kernel just, but it's start.
>
> Simon, does data cache/MMC/USB work properly when booting u-boot
> "natively" rather then chainloading from coreboot or does it have
> similar issues?
>
> Fwiw, I've attached the output of u-boot running onthe board (with
> CONFIG_SYS_DCACHE_OFF enabled).
>

Nice work!

I have the data cache enabled. USB does not work. MMC works OK (I can
boot a kernel from the internal eMMC).

I'm not sure about the cache, it seems odd. I wonder if there is
something broken in the cache set, and U-Boot needs to fix it?

Regards,
Simon