[U-Boot] mmc: sdhci: Add a quirk to add delay during completion of sdhci_send_cmd

[Jagan Teki]

Hi Tushar,

On Tue, Apr 9, 2013 at 3:23 PM, Jaehoon Chung <jh80.chung at samsung.com> wrote:
> On 04/09/2013 06:41 PM, Jagan Teki wrote:
>> Hi Tushar,
>>
>> On Mon, Apr 8, 2013 at 9:22 AM, Tushar Behera <tushar.behera at linaro.org> wrote:
>>> On 04/07/2013 10:27 AM, Jagan Teki wrote:
>>>> Hi,
>>>>
>>>> I saw that you have been added the SDHCI_QUIRK_WAIT_SEND_CMD on below commit
>>>> http://git.denx.de/?p=u-boot.git;a=commitdiff;h=13243f2eafc4292917178051fe1bb5aab2774dca
>>>>
>>>> I need few quires regarding the QUIRK delay.
>>>> 1. Why the delay is 1000
>>>> +       if (host->quirks & SDHCI_QUIRK_WAIT_SEND_CMD)
>>>> +               udelay(1000);
>>>> +
>>>> 2. is this delay specific to s5p_sdhci  controller?
>>>
>>
>> BTW:
>> Can you please help me out what is the reason for max and min clocks
>> are at 52000000 and 400000 respectively.
>>
>> As per my knowledge the max clock of sdhci on spec-2 is 50000000
>> (50Mhz), I may be in correct.
> Right..But eMMC can use up to 52MHz.
> And see into the drivers/mmc/mmc.c..SD-card's max_dtr is set to 50MHz, if card is supported HS_MODE.

Ok, Thanks for your information.
means the max_clk 52MHz will handle eMMC as well.. is it?
What is this min_clk as 400000?
Any idea if the max_clk and min_clk value are initialized to 0 so-that
sdhci will re-init based on the  capabilities register
Base_Clock_Frequency_for_SD_Clock[13:8].?

Thanks,
Jagan.

>>
>> Request for your help.
>>
>> Thanks,
>> Jagan.
>>
>>> This was specific to s5p_sdhci driver so as to replicate the behavior of
>>> s5p_mmc driver.
>>>
>>>> 3. I have an issue "Controller never released inhibit bit(s)"
>>>>    but when I enable this quirk on my driver with udelay(10000), it's
>>>> working.
>>>
>>> I am not sure about the exact delay as per the spec. I have added
>>> Jaehoon to CC who might have additional information about this.
>>>
>>>>
>>>> Could you please help me.
>>>>
>>>> Thanks,
>>>> Jagan.
>>>>
>>>
>>>
>>> --
>>> Tushar Behera
>>
>