Re: u-boot debug, was: Re: U-boot on RPI3, sees disk but won't boot it

From: Mark Millard <marklmi_at_yahoo.com>
Date: Mon, 10 Oct 2022 07:08:15 UTC
On 2022-Oct-9, at 21:44, Mark Millard <marklmi@yahoo.com> wrote:

> On 2022-Oct-9, at 19:29, Mark Millard <marklmi@yahoo.com> wrote:
> 
>> On 2022-Oct-9, at 17:28, bob prohaska <fbsd@www.zefox.net> wrote:
>>> . . .
>>> Is it possible to boot ARMv7 on a Pi3 or Pi4?
>> 
>> There is no ARMv7 EDK2 so far as I know. So the ARMv7 U-Boot would
>> need to be in use U-Boot and the ARMv7 RPi* firmware files would
>> need to be present.
>> 
>> https://www.raspberrypi.com/news/raspberry-pi-os-64-bit/ (the end of
>> the BETA) is from this year. Prior to that the official support was
>> all ARMv7 or ARMv6 based.
>> 
>>> That would let me
>>> set up a single SATA drive that could be tested on any host in
>>> my collection with any candidate USB-SATA bridge. 
>> 
>> As I understand, such could work. But I've not tested such
>> combinations. I doubt that those FreeBSD folks that developed
>> the RPi4B support did much testing of armv7 use then or since.
>> 
>> I'm not sure how much RAM would be put to use on a RPi4B with
>> more than 2 GiBytes of RAM.
> 
> My experiments indicate that the armv7 u-boot ( u-boot-rpi2 )
> does not deal with the RPi4B's USB:
> 
> U-Boot 2022.04 (May 13 2022 - 23:52:35 +0000)
> 
> DRAM:  alloc space exhausted
> 947 MiB
> RPI 4 Model B (0xd03114)
> Core:  195 devices, 9 uclasses, devicetree: board
> MMC:   mmc@7e300000: 3, emmc2@7e340000: 0
> Loading Environment from FAT... Card did not respond to voltage select! : -110
> In:    serial
> Out:   serial
> Err:   serial
> Net:   No ethernet found.
> starting USB...
> No working controllers found
> Hit any key to stop autoboot:  0 
> Card did not respond to voltage select! : -110
> MMC Device 1 not found
> no mmc device at slot 1
> MMC Device 2 not found
> no mmc device at slot 2
> starting USB...
> No working controllers found
> USB is stopped. Please issue 'usb start' first.
> starting USB...
> No working controllers found
> . . .
> 
> Also, if I had a EtherNet dongle plugged in, it did not
> even get that far. Note the "No ethernet found" as well
> (no dongle present).
> 

My experiments with:

A) An RPi2B v1.1 (so actual armv7)
and:
B) An RPi3B (so aarch64, but a pre-RPi4B design)

are incomplete but both work the same for as far
as I got them to go. I got them to:


. . .
Using DTB provided by EFI at 0x7ef6000.
Kernel entry at 0x36a00200...
Kernel args: (null)


and there is no more output.

This means that the following all happened:

A) RPi* firmware got U-Boot started.
B) U-Boot got the FreeBSD loader started.
C) The FreeBSD loader got as far as those messages
   after loading the kernel.

Beyond that I do not know what is going on.

Still, unlike the RPi4B, the RPi3B looks to be handled
by the armv7 context (at least for as far as I got).


===
Mark Millard
marklmi at yahoo.com