Need advise with u-boot on SH-7785LCR

[Simon Glass]

Hi John,

On Sat, 4 Nov 2023 at 13:59, John Paul Adrian Glaubitz
<glaubitz at physik.fu-berlin.de> wrote:
>
> Hello!
>
> I am Debian's maintainer for the SuperH (sh4) port as well as one of the upstream
> maintainers of SuperH support in the kernel. I own various SuperH boards with one
> of them being the Renesas SH-7785LCR board which used to be supported by u-boot
> up to including v2019.01.
>
> My board is currently running v2014.01 with the following output:
>
> U-Boot 2014.01 (Jan 30 2015 - 11:01:14)
>
> CPU: SH4
> BOARD: Renesas Technology Corp. R0P7785LC0011RL
> DRAM:  384MB
> Flash: 64MB
> PCI: SH7780 PCI host bridge found.
> PCI:   Bus Dev VenId DevId Class Int
>   00:00.0     - 10ec:8169 - Network controller
>   00:01.0     - 1095:3512 - Mass storage controller
> In:    serial
> Out:   serial
> Err:   serial
> Net:   RTL8169#0
> Warning: RTL8169#0 MAC addresses don't match:
> Address in SROM is         00:00:87:6b:bd:72
> Address in environment is  74:90:50:00:02:03
>
> Hit any key to stop autoboot:  0
> => printenv
> baudrate=115200
> bootargs=console=ttySC1,115200 root=/dev/sda1 ip=dhcp
> bootcmd=usb reset; fatload usb 0:1 0x89000000 uImage-git.gz; pmb ; bootm
> bootdelay=3
> bootdevice=0:1
> ethact=RTL8169#0
> ethaddr=74:90:50:00:02:03
> stderr=serial
> stdin=serial
> stdout=serial
> usbload=usb reset; fatload usb 0:1 0x89000000 uImage-git.gz; pmb ; bootm
> ver=U-Boot 2014.01 (Jan 30 2015 - 11:01:14)
>
> Environment size: 396/262140 bytes
> =>
>
> I am currently running into the problem that u-boot hangs after verifying the image
> checksum when trying to boot a cross-built kernel. This has happened in the past before
> while often the kernel would boot just fine after performing some resets.
>
> When the boot hangs, it looks like this:
>
> => usb reset; fatload usb 0:1 0x89000000 uImage-next.gz ; pmb ; bootm
> (Re)start USB...
> USB0:   scanning bus 0 for devices... 2 USB Device(s) found
>        scanning usb for storage devices... 1 Storage Device(s) found
> reading uImage-next.gz
> 4348967 bytes read in 2470 ms (1.7 MiB/s)
> ## Booting kernel from Legacy Image at 89000000 ...
>    Image Name:   Linux-6.6.0-rc1-00007-g63f1ee206
>    Image Type:   SuperH Linux Kernel Image (gzip compressed)
>    Data Size:    4348903 Bytes = 4.1 MiB
>    Load Address: 80001000
>    Entry Point:  80002000
>    Verifying Checksum ... OK
> (hangs)
>
> My first attempt at fixing this would be upgrading the board to v2019.01.
>
> Unfortunately, I have not found any documentation yet which explains how to upgrade
> the u-boot firmware on this particular board. Does anyone know whether there are
> any tools for this available? I can see an "erase" command in the u-boot command
> list, but there is no command for writing a new u-boot firmware to flash.
>
> I have already reached out to Nobuhiro Iwamatsu who is the original author of support
> for these boards in u-boot and also provided me with the particular hardware. However,
> I haven't heard back from him yet.
>
> Another question that I have is the loading address. I need to load the kernel to the
> loading address 0x89000000 as otherwise the machine won't boot. However, according to
> the output of the u-boot mkimage tool, the loading address is 0x80001000 and not
> 0x8900000. Could the different addresses be related to the unusual memory layout
> of this board which has to be switched with the "pmb" command prior boot?
>
> Also, I was wondering what it would take to convert this particular board to CONFIG_DM_USB
> and CONFIG_DM_PCI. I would be interested in getting support for SuperH boards in u-boot
> into a better shape with broader hardware support.
>
> From the kernel side, we're currently working on converting SuperH to Device Trees, so I'm
> expecting SuperH Linux to be better suited to modern versions of u-boot in the future.
>
> For now, it would be a great help if anyone could help me with the hanging boot issue.

Is it possible to check if it reaches the kernel? E.g. with
earlyprintk ? It would be good to know if U-Boot managers to jump to
Linux, or not.

Regards,
Simon