[U-Boot] [PATCH v7 2/3] mmc: meson: add MMC driver for Meson GX (S905)

[Simon Glass]

Hi,

On 17 April 2017 at 16:39, Jaehoon Chung <jh80.chung at samsung.com> wrote:
> On 04/18/2017 06:18 AM, Heinrich Schuchardt wrote:
>> On 04/16/2017 09:34 PM, Simon Glass wrote:
>>> Hi Alex,
>>>
>>> On 16 April 2017 at 04:08, Alexander Graf <agraf at suse.de> wrote:
>>>>
>>>>
>>>> On 16.04.17 04:09, Heinrich Schuchardt wrote:
>>>>>
>>>>> On 04/15/2017 11:51 PM, Andreas Färber wrote:
>>>>>>
>>>>>> Am 15.04.2017 um 23:16 schrieb Andreas Färber:
>>>>>>>
>>>>>>> Am 15.04.2017 um 23:04 schrieb Alexander Graf:
>>>>>>>>>
>>>>>>>>> Am 15.04.2017 um 22:34 schrieb Andreas Färber <afaerber at suse.de>:
>>>>>>>>>>
>>>>>>>>>> Am 15.04.2017 um 20:27 schrieb Alexander Graf:
>>>>>>>>>>>
>>>>>>>>>>> On 15.04.17 20:18, Heiner Kallweit wrote:
>>>>>>>>>>>>
>>>>>>>>>>>> Am 15.04.2017 um 17:05 schrieb Andreas Färber:
>>>>>>>>>>>> But for the Vega S95 Telos I needed to disable the first of three
>>>>>>>>>>>> MMC
>>>>>>>>>>>> nodes (SDIO) - otherwise U-Boot would happily iterate over them for
>>>>>>>>>>>> distro boot with Heinrich's patch, but GRUB would come up with no
>>>>>>>>>>>> disks,
>>>>>>>>>>>> so that booting failed. I'm not yet sure why, maybe it's a
>>>>>>>>>>>> UEFI-side
>>>>>>>>>>>> problem in that it is the first MMC device that is absent rather
>>>>>>>>>>>> than
>>>>>>>>>>>> the last one?
>>>>>>>>>>>>
>>>>>>>>>>> I don't own this device so I can just provide a guess.
>>>>>>>>>>> Based on DT the device ordering most likely is:
>>>>>>>>>>> mmc0: SDIO
>>>>>>>>>>> mmc1: SD
>>>>>>>>>>> mmc2: eMMC
>>>>>>>>>
>>>>>>>>> [...]
>>>>>>>>>>
>>>>>>>>>> If grub comes up, distro boot has successfully found the target
>>>>>>>>>> binary
>>>>>>>>>> and executed it. For some reason, grub can not find its boot origin
>>>>>>>>>> though.
>>>>>>>>>>
>>>>>>>>>> Andreas, please add debug prints like the ones below and check that
>>>>>>>>>> the
>>>>>>>>>> device names match:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> U-Boot 2017.05-rc1-00318-g082535f-dirty (Apr 15 2017 - 22:29:17 +0200)
>>>>>>>>> vega-s95
>>>>>>>>>
>>>>>>>>> DRAM:  2 GiB
>>>>>>>>> MMC:   mmc at 70000: 0, mmc at 72000: 1, mmc at 74000: 2
>>>>>>>>> Using default environment
>>>>>>>>>
>>>>>>>>> In:    serial at 4c0
>>>>>>>>> Out:   serial at 4c0
>>>>>>>>> Err:   serial at 4c0
>>>>>>>>> Net:   eth0: ethernet at c9410000
>>>>>>>>> Hit any key to stop autoboot:  0
>>>>>>>>> mmc_init: -95, time 1806
>>>>>>>>> MMC Device 0 not found
>>>>>>>>> no mmc device at slot 0
>>>>>>>>> switch to partitions #0, OK
>>>>>>>>> mmc1 is current device
>>>>>>>>> Scanning mmc 1:1...
>>>>>>>>> Setting boot device name to '//boot/dtb/amlogic/meson-gxbb-v'
>>>>>>>>> 20335 bytes read in 43 ms (460.9 KiB/s)
>>>>>>>>> Found EFI removable media binary efi/boot/bootaa64.efi
>>>>>>>>> Setting boot device name to '/efi/boot/bootaa64.efi'
>>>>>>>>> reading efi/boot/bootaa64.efi
>>>>>>>>> 129024 bytes read in 13 ms (9.5 MiB/s)
>>>>>>>>> ## Starting EFI application at 01080000 ...
>>>>>>>>> mmc_init: -95, time 1807
>>>>>>>>> Found 0 disks
>>>>>>>>
>>>>>>>>
>>>>>>>> That looks like efi_disk didn't manage to enumerate any devices?
>>>>>>>
>>>>>>>
>>>>>>> Apparently. The last line comes from
>>>>>>> lib/efi_loader_efi_disk:efi_disk_register(), and CONFIG_BLK=y. As you
>>>>>>> can see, there is not a single "Scanning disk" line, so I guess we do
>>>>>>> not iterate over uclass devices properly?
>>>>>>>
>>>>>>> On the Odroid-C2 I get this:
>>>>>>>
>>>>>>> Scanning disk mmc at 72000.blk...
>>>>>>> Card did not respond to voltage select!
>>>>>>> mmc_init: -95, time 9
>>>>>>> Found 1 disks
>>>>>>>
>>>>>>> Therefore my guess that it matters at what point in time - before or
>>>>>>> after the disk we want - the error accessing an MMC device happens.
>>>>>>
>>>>>>
>>>>>> For comparison, Vega S95 with first MMC node disabled in DT:
>>>>>>
>>>>>> Scanning disk mmc at 72000.blk...
>>>>>> Adding disk device 'mmc at 72000.blk'
>>>>>> ** First descriptor is NOT a primary desc on 1:1 **
>>>>>> Scanning disk mmc at 74000.blk...
>>>>>> Adding disk device 'mmc at 74000.blk'
>>>>>> Found 2 disks
>>>>>>
>>>>>> Regards,
>>>>>> Andreas
>>>>>>
>>>>> By adding sd_mmc_a to the odroid-c2.dts I was able to reproduce the
>>>>> problem on the Odroid C2.
>>>>>
>>>>> While booting from SD card via booti still worked
>>>>> bootefi would not find any block device:
>>>>>
>>>>> => bootefi hello
>>>>> ## Starting EFI application at 01000000 ...
>>>>> WARNING: Invalid device tree, expect boot to fail
>>>>> efi_add_memory_map: 0x7cf53000 0x1 2 yes
>>>>> uclass_find_device_by_seq: 0 -1
>>>>> uclass_find_device_by_seq: 0 0
>>>>>    - -1 -1
>>>>>    - -1 -1
>>>>>    - -1 -1
>>>>>    - not found
>>>>> set_state_simple op missing
>>>>> blk_get_device: if_type=6, devnum=0: mmc at 70000.blk, 6, 0
>>>>> mmc_init: -95, time 1807
>
> This error number is "EOPNOTSUPP". Is "cfg->voltages" correct in meson_gx_mmc.c?

Or it could just be that there is no card inserted? See
mmc_start_init(). It would be good to update mmc.c to return different
errors for the different cases.

Regards,
Simon