[U-Boot] ZynqMP breakage

[Simon Glass]

Hi Alex,

On 6 September 2016 at 06:55, Alexander Graf <agraf at suse.de> wrote:
> On 09/06/2016 02:52 PM, Simon Glass wrote:
>>
>> Hi Alex,
>>
>> On 6 September 2016 at 03:09, Alexander Graf <agraf at suse.de> wrote:
>>>
>>> On 09/06/2016 03:05 AM, Simon Glass wrote:
>>>>
>>>> Hi Alex,
>>>>
>>>> On 5 September 2016 at 04:51, Alexander Graf <agraf at suse.de> wrote:
>>>>>
>>>>> On 08/19/2016 08:45 AM, Michal Simek wrote:
>>>>>>
>>>>>> On 16.8.2016 20:39, Alexander Graf wrote:
>>>>>>>
>>>>>>> Hi Michal,
>>>>>>>
>>>>>>> I just tried to run the latest u-boot master + a few patches to
>>>>>>> implement
>>>>>>> generic PSCI RTS support on zynqmp and got this:
>>>>>>>
>>>>>>> e
>>>>>>> U-Boot 2016.09-rc1-00453-ga0592f1 (Aug 16 2016 - 20:27:40 +0200)
>>>>>>> Xilinx
>>>>>>> ZynqMP ZCU102
>>>>>>>
>>>>>>> I2C:   ready
>>>>>>> DRAM:  4 GiB
>>>>>>> EL Level:       EL2
>>>>>>> MMC:   sdhci at ff170000: 0
>>>>>>> Using default environment
>>>>>>>
>>>>>>> In:    serial at ff000000
>>>>>>> Out:   serial at ff000000
>>>>>>> Err:   serial at ff000000
>>>>>>> Bootmode: SD_MODE1
>>>>>>> SCSI:  SATA link 0 timeout.
>>>>>>> Target spinup took 0 ms.
>>>>>>> AHCI 0001.0301 32 slots 2 ports 6 Gbps 0x3 impl SATA mode
>>>>>>> flags: 64bit ncq pm clo only pmp fbss pio slum part ccc apst
>>>>>>> scanning bus for devices...
>>>>>>> "Synchronous Abort" handler, esr 0x96000004
>>>>>>> ELR:     7ff42d20
>>>>>>> LR:      7ff3ff10
>>>>>>> x0 : 0000000000000000 x1 : 0000000000000000
>>>>>>> x2 : 0000000000000001 x3 : 000000007df1aa80
>>>>>>> x4 : aaaaaaaaaaaaaaaa x5 : 0000000000000001
>>>>>>> x6 : 0000000000000200 x7 : 0000000000000004
>>>>>>> x8 : 000000007ff9f800 x9 : 0000000000000008
>>>>>>> x10: 000000007ff9f8f0 x11: 0000000000000000
>>>>>>> x12: 00000000ffffffff x13: 00000000ffffffff
>>>>>>> x14: 000000007ff8242f x15: 000000007ff82435
>>>>>>> x16: 000000007ff84388 x17: 000000007ff84388
>>>>>>> x18: 000000007df1ade8 x19: 000000007df1aa80
>>>>>>> x20: 000000007ff92cb8 x21: 000000007ff9f800
>>>>>>> x22: 000000007ff9f000 x23: 0000000000000078
>>>>>>> x24: 000000007ff9f8f0 x25: 0000000000000000
>>>>>>> x26: 000000007ff9f800 x27: 000000007ff9f000
>>>>>>> x28: 000000007ff9fb00 x29: 000000007df1aca0
>>>>>>>
>>>>>>> Resetting CPU ...
>>>>>>>
>>>>>>> resetting …
>>>>>>>
>>>>>>> Is this a known problem?
>>>>>>
>>>>>> Is this issue with usb?
>>>>>> I have usb off on zcu102 that's why if this usb issue
>>>>>> I am not aware about it.
>>>>>
>>>>>
>>>>> After a bit of digging, turns out it's CONFIG_BLK. If I disable that
>>>>> things
>>>>> work again (albeit without mmc access, since that one requires
>>>>> CONFIG_BLK
>>>>> now).
>>>>
>>>> I don't have a zynqmp device, so cannot test with that unfortunately.
>>>
>>>
>>> Well, QEMU supports zcu102 emulation in the latest version, so you could
>>> use
>>> that to emulate the board:
>>>
>>>    $ qemu-system-aarch64 -M xlnx-zcu102 -kernel u-boot.elf -nographic -m
>>> 2G
>>> -drive file=u-boot,id=d,if=none -device ide-drive,drive=d,bus=ide.0
>>>
>>> However, I don't see the data abort with the emulated device, only with
>>> actual hardware. Probably because real hardware is more upset about
>>> reading
>>> from address 0 ;). But I can provoke the oops even in QEMU if I unmap the
>>> first page from the memory map using the patch below.
>>>
>>> The oops happens in blk_dread because block_dev->bdev is NULL.
>>
>> Yes, this field really should be removed. As the comment says it's a
>> hangover from pre-CONFIG_BLK where functions use a struct blk_dev * to
>> specify the block device instead of a struct udevice *. It came up
>> recently on a patch you sent also which is why I am so against using
>> it.
>>
>> That said, I'm not sure why it is unset. The path should be:
>>
>> sdhci_bind()
>> mmc_bind()
>> blk_create_devicef()
>> blk_create_device()
>> which sets:
>>
>> desc->bdev = dev;
>>
>> [snip]
>
>
> The special case about ZynqMP is that it has 2 storage backends, one that
> uses DM (the sdhc controller) and one that isn't converted to DM (the AHCI
> controller). I guess something goes wrong with the latter.

OK, well it would be good to convert it. It certainly won't work
without it and I'm a little surprised that it compiles :-)

Regards,
Simon