Re: [PATCH 3/3] arm64: dts: rockchip: fix RockPro64 sdmmc settings【请注意，邮件由linux-rockchip-bounces+shawn.lin=rock-chips.com@lists.infradead.org代发】

[Robin Murphy <robin.murphy@arm.com>]

On 04/10/2019 04:39, Soeren Moch wrote:
> 
> 
> On 04.10.19 04:13, Shawn Lin wrote:
>> On 2019/10/4 8:53, Soeren Moch wrote:
>>>
>>>
>>> On 04.10.19 02:01, Robin Murphy wrote:
>>>> On 2019-10-03 10:50 pm, Soeren Moch wrote:
>>>>> According to the RockPro64 schematic [1] the rk3399 sdmmc
>>>>> controller is
>>>>> connected to a microSD (TF card) slot, which cannot be switched to
>>>>> 1.8V.
>>>>
>>>> Really? AFAICS the SDMMC0 wiring looks pretty much identical to the
>>>> NanoPC-T4 schematic (it's the same reference design, after all), and I
>>>> know that board can happily drive a UHS-I microSD card with 1.8v I/Os,
>>>> because mine's doing so right now.
>>>>
>>>> Robin.
>>> OK, the RockPro64 does not allow a card reset (power cycle) since
>>> VCC3V0_SD is directly connected to VCC3V3_SYS (via R89555), the
>>> SDMMC0_PWH_H signal is not connected. So the card fails to identify
>>> itself after suspend or reboot when switched to 1.8V operation.

Ah, thanks for clarifying - I did overlook the subtlety that U12 and 
friends have "NC" as alternative part numbers, even though they aren't 
actually marked as DNP. So it's still not so much "cannot be switched" 
as "switching can lead to other problems".

>>
>> I believe we addressed this issue long time ago, please check:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6a11fc47f175c8d87018e89cb58e2d36c66534cb
>>
> Thanks for the pointer.
> In this case I guess I should use following patch instead:
> 
> --- rk3399-rockpro64.dts.bak    2019-10-03 22:14:00.067745799 +0200
> +++ rk3399-rockpro64.dts    2019-10-04 00:02:50.047892366 +0200
> @@ -619,6 +619,8 @@
>       max-frequency = <150000000>;
>       pinctrl-names = "default";
>       pinctrl-0 = <&sdmmc_clk &sdmmc_cmd &sdmmc_bus4>;
> +    sd-uhs-sdr104;
> +    vqmmc-supply = <&vcc_sdio>;
>       status = "okay";
>   };
>   
> When I do so, the sd card is detected as SDR104, but a reboot hangs:
> 
> Boot1: 2018-06-26, version: 1.14
> CPUId = 0x0
> ChipType = 0x10, 286
> Spi_ChipId = c84018
> no find rkpartition
> SpiBootInit:ffffffff
> mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000
> mmc: ERROR: Card did not respond to voltage select!
> emmc reinit
> mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000
> mmc: ERROR: Card did not respond to voltage select!
> emmc reinit
> mmc: ERROR: SDHCI ERR:cmd:0x102,stat:0x18000
> mmc: ERROR: Card did not respond to voltage select!
> SdmmcInit=2 1
> mmc0:cmd5,32
> mmc0:cmd7,32
> mmc0:cmd5,32
> mmc0:cmd7,32
> mmc0:cmd5,32
> mmc0:cmd7,32
> SdmmcInit=0 1
> 
> So I guess I should use a different miniloader for this reboot to work!?
> Or what else could be wrong here?

Hmm, I guess this is "the Tinkerboard problem" again - the patch above 
would be OK if we could get as far as the kernel, but can't help if the 
offending card is itself the boot medium. There was a proposal here:

https://patchwork.kernel.org/patch/10817217/

although I'm not sure what if any progress has been made since then.

Robin.