[U-Boot] [PATCH 1/4] mmc: meson-gx: Fix tx phase in the tuning process

[Neil Armstrong]

Hi,

On 27/11/2019 15:42, Anand Moon wrote:
> Hi Neil,
> 
> On Wed, 27 Nov 2019 at 18:30, Neil Armstrong <narmstrong at baylibre.com> wrote:
>>
>> Hi,
>>
>> On 26/11/2019 22:12, Anand Moon wrote:
>>> odroid n2 eMMC module would failed to boot up,
>>> because of TX phase clk failure, fix the typo in
>>> TX phase macro to help tune correct clk freqency.
>>>
>>> Before these changes.
>>>   clock is enabled (380953Hz)
>>>   clock is enabled (25000000Hz)
>>> after these changes
>>>   clock is enabled (380953Hz)
>>>   clock is enabled (25000000Hz)
>>>   clock is enabled (52000000Hz)
>>>   clock is enabled (52000000Hz)
>>>   clock is enabled (52000000Hz)
>>>
>>> Signed-off-by: Anand Moon <linux.amoon at gmail.com>
>>> ---
>>> Tested on
>>> new orange - eMMC AJNB4R 14.6 GiB MMC 5.1
>>> old back   - eMMC CGND3R 58.2 GiB MMC 5.0
>>> ---
>>>  drivers/mmc/meson_gx_mmc.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mmc/meson_gx_mmc.c b/drivers/mmc/meson_gx_mmc.c
>>> index 031cc79ccb..87bea2888b 100644
>>> --- a/drivers/mmc/meson_gx_mmc.c
>>> +++ b/drivers/mmc/meson_gx_mmc.c
>>> @@ -53,7 +53,7 @@ static void meson_mmc_config_clock(struct mmc *mmc)
>>>       meson_mmc_clk |= CLK_CO_PHASE_180;
>>>
>>>       /* 180 phase tx clock */
>>> -     meson_mmc_clk |= CLK_TX_PHASE_000;
>>> +     meson_mmc_clk |= CLK_TX_PHASE_180;
>>>
>>>       /* clock settings */
>>>       meson_mmc_clk |= clk_src;
>>>
>>
>> I don't understand what this change helps, the linux driver sets the TX phase to 0,
>> why 180 would help here ?
>>
>> Neil
> 
> I narrow down to this small changes, without this small change
> it fails to detect the eMMC module. See the below log.
> 
> U-Boot 2020.01-rc3-00082-g4b19b89ca4-dirty (Nov 27 2019 - 18:56:37
> +0530) odroid-n2
> 
> Model: Hardkernel ODROID-N2
> SoC:   Amlogic Meson G12B (S922X) Revision 29:a (40:2)
> DRAM:  3.8 GiB
> mmc_bind: alias ret=-2, devnum=-1
> mmc_bind: alias ret=-2, devnum=-1
> MMC:   clock is enabled (380953Hz)
> clock is enabled (380953Hz)
> sd at ffe05000: 0, mmc at ffe07000: 1
> In:    serial at 3000
> Out:   serial at 3000
> Err:   serial at 3000
> Net:   gpio_request_tail: Node 'ethernet at ff3f0000', property
> 'snps,reset-gpio', failed to request GPIO index 0: -2
> 
> Warning: ethernet at ff3f0000 (eth0) using random MAC address - 26:1e:2a:2a:67:d6
> eth0: ethernet at ff3f0000
> Hit any key to stop autoboot:  0
> clock is disabled (0Hz)
> regulator_common_set_enable: dev='regulator-tflash_vdd', enable=1,
> delay=0, has_gpio=1
> regulator_common_set_enable: done
> clock is enabled (380953Hz)
> Card did not respond to voltage select!
> gpio_request_tail: Node 'regulator-vcc_3v3', property 'gpio', failed
> to request GPIO index 0: -2
> Regulator 'regulator-vcc_3v3' optional enable GPIO - not found! Error: -2
> gpio_request_tail: Node 'regulator-flash_1v8', property 'gpio', failed
> to request GPIO index 0: -2
> Regulator 'regulator-flash_1v8' optional enable GPIO - not found! Error: -2
> clock is disabled (0Hz)
> regulator_common_set_enable: dev='regulator-vcc_3v3', enable=1,
> delay=0, has_gpio=0
> clock is enabled (380953Hz)
> clock is enabled (25000000Hz)
> unable to select a mode
> switch to partitions #0, OK
> mmc1(part 0) is current device
> ** No partition table - mmc 1 **
> MMC Device 2 not found
> no mmc device at slot 2
> starting USB...
> Bus usb at ff500000: gpio_request_tail: Node 'regulator-vcc_5v', property
> 'gpio', failed to request GPIO index 0: -2
> Regulator 'regulator-vcc_5v' optional enable GPIO - not found! Error: -2
> regulator_common_set_enable: dev='regulator-usb_pwr_en', enable=1,
> delay=0, has_gpio=1
> regulator_common_set_enable: done
> Register 3000140 NbrPorts 3
> Starting the controller
> USB XHCI 1.10
> scanning bus usb at ff500000 for devices... 1 USB Device(s) found
>        scanning usb for storage devices... 0 Storage Device(s) found

I have the same behavior with SEI610 on SM1, I need to check this fixes the issue...

Neil

> 
> -Anand
>