On Sep 12, 2012, at 9:02 PM, Huang Changming-R66093 wrote:
>>>
>>>> -----Original Message-----
>>>> From: Chris Ball [mailto:[email protected]]
>>>> Sent: Wednesday, September 12, 2012 4:59 AM
>>>> To: Kumar Gala
>>>> Cc: Huang Changming-R66093; [email protected] list;
>>>> linux- [email protected]; Anton Vorontsov
>>>> Subject: Re: [PATCH 2/3] powerpc/esdhc: add property to disable the
>>>> CMD23
>>>>
>>>> Hi,
>>>>
>>>> On Tue, Sep 11 2012, Kumar Gala wrote:
>>>>> thanks for the info. Do you know what's required on controller side
>>>>> to handle cards that support CMD23?
>>>>>
>>>>> I'm trying to figure out if older controller's on FSL SoCs are
>>>>> missing some feature to allow CMD23 to work (vs Auto-CMD23).
>>>>
>>>> It seems plausible that it's just not implemented on these controllers.
>>>> It's a little strange, since the command's been specified for so long
>>>> and we haven't seen any other controllers with problems. The patch
>>>> would be correct if this is true.
>>>>
>>>
>>> I didn't find any description about it, but after testing on FSL
>> silicones, I got this result:
>>> Some silicones support this command, and some silicones don't support
>> it, which will cause I/O error.
>>
>> Can you list out which SoCs support it and which don't. Having this list
>> will be useful in understanding which controller versions supported it.
>>
> P1020, p1021, p1022, p1024, p1015 and p4080 can't support it.
> Mpc8536, p2020, and the other current DPAA silicon (e.g. p5020, p3041)
> support it.
Based on this, why don't we use the HOSTVER register to detect instead of
device tree:
#define FSL_SDHC_VER_1_0 0x00
#define FSL_SDHC_VER_1_1 0x01
#define FSL_SDHC_VER_2_0 0x10
#define FSL_SDHC_VER_2_1 0x11
#define FSL_SDHC_VER_2_2 0x12
#define FSL_SDHC_VER_2_3 0x13
unsigned int vendor_version;
vendor_version = sdhci_readw(host, SDHCI_HOST_VERSION);
vendor_version = (vendor_version & SDHCI_VENDOR_VER_MASK) >>
SDHCI_VENDOR_VER_SHIFT;
if ((vendor_version == FSL_SDHC_VER_1_1) || (vendor_version ==
FSL_SDHC_VER_2_2))
host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
- k
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