[U-Boot] [PATCH] Revert "fdt: Fix fdtdec_get_addr_size() for 64-bit"

[Stephen Warren]

On 09/02/2015 01:54 PM, Stephen Warren wrote:
> On 09/02/2015 01:39 PM, Tom Warren wrote:
>>
>>
>>> -----Original Message-----
>>> From: Stephen Warren
>>> Sent: Wednesday, September 02, 2015 1:05 PM
>>> To: Tom Warren; Simon Glass
>>> Cc: Bin Meng; Thierry Reding; Tom Rini; U-Boot Mailing List
>>> Subject: Re: [U-Boot] [PATCH] Revert "fdt: Fix fdtdec_get_addr_size() for 64-
>>> bit"
>>>
>>> On 09/02/2015 09:52 AM, Tom Warren wrote:
>>>> Simon, et al,
>>>>
>>>>> Simon Glass wrote at Friday, August 14, 2015 3:05 AM:
>>>>> I plan to apply this revert to u-boot-x86 (where SPI is currently
>>>>> broken) and (once it has a bit more testing) also this patch which I
>>>>> think makes the change in a safer way:
>>>>>
>>>>> https://patchwork.ozlabs.org/patch/504918/
>>>>>
>>>>> At present that patch breaks at least one x86 board and I have not
>>>>> dug into it yet.
>>>>>
>>>>> The revert should not break tegra, according to Stephen.
>>>>
>>>> Unfortunately, my testing on P2571 with TOT u-boot-tegra (rebased against
>>> TOT u-boot/master this morning) shows that that is not true.
>>>>
>>>> The revert of the disputed 'fdtdec_get_addr_size' patch _does_ break Tegra
>>> 64-bit (P2571, at least). Nyan-big is OK.  With Simon's revert in place, my board
>>> just loops on SPL signon, so I assume it's faulting, etc. in CPU init.  Note that this
>>> is the current state of TOT u-boot/master.
>>>
>>> I'm a bit confused. So far, we don't support SPL on T210 since we assume some
>>> other bootloader runs on the boot CPU and starts just the main U-Boot on the
>>> main CPU. It sounds like you're testing some local-only SPL support?
>>
>> Currently there are a couple of ways to get T210 64-bit U-Boot loaded/executed. The first is the way I've always done it (during development and today) - use a 32-bit SPL that I built when I first ported 32-bit U-Boot to T210. I've saved away the SPL portion as a binary, and combine it with the current 64-bit T210 U-Boot proper when building my image.  It's always worked up to now.  What I'm seeing is a failure in the 64-bit CPU U-Boot portion. I just mentioned the looping SPL signon symptom because that's what I see as the indicator of a broken 64-bit image.
> 
> Oh I see; the SPL is only looping because the main U-Boot binary
> crashes/... and resets the CPU, hence re-executing the SPL. I thought
> you were referring to a loop purely within SPL.
> 
> Now it makes more sense.
> 
>> The other way is to use your proprietary NV bootloader for the 32-bit portion (this will become the de facto standard when we release said NV bootloader code as open-source, or a binary first-stage loader 'tool').  I haven't tried that, since my way works and is an easy part of my workflow.
>>
>> If you can point me to your boot CPU loader internally, I can try your method and see if it makes a difference, but I doubt it will.
> 
> I sent you an internal email message.
> 
> Perhaps you could also try my upstream U-Boot dev branch at:
> 
> repo git://github.com/swarren/u-boot.git branch tegra_dev
> 
> That has the revert of the original patch in, but also has the following
> replacement which you'd want to revert (or perhaps best: try with and
> without it):
> 
> c1fd5e1d5586 fdt: add new fdt address parsing functions
> 
> I'm sure I tested Simon's revert at the time I said it was OK. I wonder
> if the revert used to work fine, but something since then fails if the
> revert is in place? I would try testing this now, but I'm travelling so
> it's a bit more painful.

I worked out how to remote control my device, and tested the current
u-boot-tegra/master (which contains the patch revert this email thread
is about) with and without "fdt: add new fdt address parsing functions"
removed, and it works fine for me.

When you're concatenating SPL+U-Boot+DTB, are you using the DTB from the
same source tree as the main U-Boot (likely by getting U-Boot+DTB from
u-boot-dtb.bin in that source tree)?