[U-Boot] [PATCH 00/22] mmc: Add support for HS200 and UHS modes

[Jaehoon Chung]

Hi,

On 05/24/2017 12:24 AM, Jean-Jacques Hiblot wrote:
> Hi,
> 
> 
> On 18/05/2017 06:27, Jaehoon Chung wrote:
>> Hi,
>>
>> On 05/13/2017 03:16 AM, Jean-Jacques Hiblot wrote:
>>> This series brings support for HS200 and UHS modes to the mmc core.
>>> It has been tested with the hsmmc driver on several platforms (DRA7,
>>> AM57x, AM437x, beaglebone black). Some modifications are required in
>>> the host driver to take advantage of this (voltage switching, tuning).
>>> The changes to the host driver will be posted a another series as this
>>> one is already long enough.
>>>
>>> The series starts with a small refactoring of th sd/mmc startup. The first 4 commits
>>> are mostly moving code around with little or no functionnal change.
>>>
>>> Then the notion of "mode" is introduced. Until now, this information wasn't
>>> kept in struct mmc. Only the clock and a flag for ddr was kept. Later the mode
>>> information will be used to select the clock frequency, the ddr flag and the
>>> tuning procedure. It will be also be check against the host capabilities.
>>>
>>> Then comes the big refactoring job in:
>>> "mmc: refactor MMC startup to make it easier to support new modes" and
>>> "mmc: refactor SD startup to make it easier to support new modes"
>>> Since the number of modes is increasing, it makes sense to try them in a more
>>> organized way. those commits use a list of supported modes and iterate through
>>> them to find the best working one. It also allows to switch more easilly from
>>> one mode to another (switching from HS200 to DDR52 to access boot partitions for example)
>>>
>>> Then there are a couple of new callback added to:
>>> - enable/disable Vdd
>>> - check if the card is busy (used during UHS voltage switching)
>>> - select the IO voltage
>>>
>>> Then Power cycle is added. Without power cycle, if a UHS card fails to enumerate in
>>> UHS mode, it can't fall back to high speed mode and card enumeration will fail.
>>>
>>> And finally the last commits add the support for HS200 and UHS.
>>> I haven't been able to test the UHS SDR104 mode by lack of compatible sdcard.
>> After testing my targets, some boards don't work fine..So i'm checking this problem..
> Jaehoon,
> 
> what kind of issues are you running into and on what platforms ?
> So far, besides the items brought-up by the reviews, there are 2 issues that are in the pipe for the next version:
>  * signal voltage selection is not done for the MMCs only for SDs.
>  * I noticed a timing constraint in voltage selection for SDs that can be a problem when trying a UHS mode with some SDs (seen only with Sandisk Ultra  64Gb micro SD class I) :  the voltage must be switched quickly after the cmd SWITCH_UHS18V has been sent, making debug messages in that context a problem. With this SD I've been able to check that SDR104 is working.

How about making the "testing-hs200-uhs" branch for this? It needs to test more..
I guess my target doesn't do the voltage change..i'm doing for ufs driver on u-boot in my local..
So i didn't see fully..today i have a free time..So i'm doing full review other thing..and about pending patches.

Thanks for waiting me.. :)

Best Regards,
Jaehoon Chung

> 
> Jean-Jacques
>>
>>> With this in place and the required changes in the HSMMC (including DAM), we observe significant
>>> improvements in the performances on a DRA7 evm:
>>> eMMC HS200: 130 MB/s
>>> eMMC DDR52: 80 MB/s
>>> sd   SDR50: 80 MB/s
>>>
>>> cheers,
>>>
>>> Jean-Jacques
>>>
>>>
>>> Jean-Jacques Hiblot (18):
>>>    mmc: split mmc_startup()
>>>    mmc: move the MMC startup for version above v4.0 in a separate
>>>      function
>>>    mmc: make ext_csd part of struct mmc
>>>    mmc: add a function to read and test the ext csd (mmc >= 4)
>>>    mmc: introduces mmc modes.
>>>    mmc: Add a fonction to dump the mmc capabilities
>>>    mmc: use mmc modes to select the correct bus speed
>>>    cmd: mmc: display the mode name and current bus speed in the mmc info
>>>    mmc: refactor SD startup to make it easier to support new modes
>>>    mmc: refactor MMC startup to make it easier to support new modes
>>>    mmc: make mmc_set_ios() return status
>>>    mmc: add power cyle support in mmc core
>>>    mmc: add a new mmc parameter to disable mmc clock
>>>    mmc: Add a execute_tuning() callback to the mmc operations.
>>>    mmc: add HS200 support in MMC core
>>>    mmc: Add a new callback function to check if the card is busy
>>>    mmc: Add support for UHS modes
>>>    mmc: Change mode when switching to a boot partition
>>>
>>> Kishon Vijay Abraham I (3):
>>>    mmc: Enable signal voltage to be selected from mmc core
>>>    mmc: Add a new callback function to enable/disable vdd
>>>    mmc: disable the mmc clock during power off
>>>
>>> Vignesh R (1):
>>>    mmc: Retry some MMC cmds on failure
>>>
>>>   cmd/mmc.c                |    3 +-
>>>   drivers/mmc/fsl_esdhc.c  |    2 +-
>>>   drivers/mmc/mmc-uclass.c |   42 ++
>>>   drivers/mmc/mmc.c        | 1220 +++++++++++++++++++++++++++++++++-------------
>>>   include/mmc.h            |  138 +++++-
>>>   5 files changed, 1058 insertions(+), 347 deletions(-)
>>>
>>
> 
> 
> 
>