Re: [PATCH V14 2/2] scsi: ufs: Add configfs support for UFS provisioning

[Sayali Lokhande <sayalil@codeaurora.org>]

Hi Evan,


On 10/3/2018 11:31 PM, Evan Green wrote:
> On Sun, Sep 23, 2018 at 11:29 PM Sayali Lokhande <sayalil@codeaurora.org> wrote:
>> This patch adds configfs support to provision UFS device at
>> runtime. This feature can be primarily useful in factory or
>> assembly line as some devices may be required to be configured
>> multiple times during initial system development phase.
>> Configuration Descriptors can be written multiple times until
>> bConfigDescrLock attribute is zero.
>>
>> Configuration descriptor buffer consists of Device and Unit
>> descriptor configurable parameters which are parsed from vendor
>> specific provisioning file and then passed via configfs node at
>> runtime to provision ufs device.
>> CONFIG_CONFIGFS_FS and CONFIG_SCSI_UFS_PROVISION needs to be enabled
>> for using this feature.
>>
>> Usage:
>> 1) To read current configuration descriptor with index X
>>     (where index X can be 0/1/2/3) :
>>     cat /config/<device_name>/ufs_config_desc_X
>>
>> 2) To write configuration descriptor with index X :
>>     echo <config_desc_buf> > /config/<device_name>/ufs_config_desc_X
>>
>> Signed-off-by: Sayali Lokhande <sayalil@codeaurora.org>
>> ---
>>   Documentation/ABI/testing/configfs-driver-ufs |  12 ++
>>   drivers/scsi/ufs/Kconfig                      |  10 ++
>>   drivers/scsi/ufs/Makefile                     |   1 +
>>   drivers/scsi/ufs/ufs-configfs.c               | 237 ++++++++++++++++++++++++++
>>   drivers/scsi/ufs/ufshcd.c                     |   3 +-
>>   drivers/scsi/ufs/ufshcd.h                     |  18 ++
>>   6 files changed, 280 insertions(+), 1 deletion(-)
>>   create mode 100644 Documentation/ABI/testing/configfs-driver-ufs
>>   create mode 100644 drivers/scsi/ufs/ufs-configfs.c
>>
>> diff --git a/Documentation/ABI/testing/configfs-driver-ufs b/Documentation/ABI/testing/configfs-driver-ufs
>> new file mode 100644
>> index 0000000..6743ea9
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/configfs-driver-ufs
>> @@ -0,0 +1,12 @@
>> +What:          /config/*/ufs_config_desc_X
>> +Date:          Jun 2018
>> +KernelVersion: 4.20
>> +Description:
>> +               This file shows bytes of the current ufs configuration descriptor
>> +               with index X (where X = 0/1/2/3) set in device. This can be used to
>> +               provision ufs device if bConfigDescrLock is 0.
>> +               For more details, refer 14.1.6.3 Configuration Descriptor and
>> +               table 14-12 - Unit Descriptor configurable parameters from specs for
>> +               description and format of each configuration descriptor parameter.
>> +               Parameters of Configuration descriptor buffer for respective index
>> +               needs to be passed as bytes in space separated format.
>> diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
>> index e27b4d4..6e7ff35 100644
>> --- a/drivers/scsi/ufs/Kconfig
>> +++ b/drivers/scsi/ufs/Kconfig
>> @@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
>>
>>            Select this if you have UFS controller on QCOM chipset.
>>            If unsure, say N.
>> +
>> +config SCSI_UFS_PROVISION
>> +       bool "Runtime UFS Provisioning support"
>> +       depends on SCSI_UFSHCD && CONFIGFS_FS
>> +       help
>> +         This enables runtime UFS provisioning support. This can be used
>> +         primarily during assembly line as some devices may be required to
>> +         be configured multiple times during initial development phase.
>> +
>> +         If unsure, say N.
>> diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
>> index 918f579..09880b9 100644
>> --- a/drivers/scsi/ufs/Makefile
>> +++ b/drivers/scsi/ufs/Makefile
>> @@ -5,5 +5,6 @@ obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-d
>>   obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
>>   obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
>>   ufshcd-core-objs := ufshcd.o ufs-sysfs.o
>> +obj-$(CONFIG_SCSI_UFS_PROVISION) += ufs-configfs.o
> Hi Sayali,
> Can you try both of your patches with "make allmodconfig". There seem
> to be a few issues compiling in that configuration. Also, as it stands
> this file is either not compiled in, or baked into the kernel, where
> it really should go into the driver. Check out the patch below for how
> Guenter patched things up in our tree:
>
> shttps://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/1255524
[Sayali] : the change pointed by you above looks good to me and will 
update it in my patch as well. ufs-configfs should be part of ufshcd-core.
I tried using "make allmodconfig".(basically updating like below for 
test) + include change pointed above and it works fine.
+CONFIG_CONFIGFS_FS=y

+CONFIG_SCSI_UFSHCD=m
+CONFIG_SCSI_UFSHCD_PLATFORM=m
+CONFIG_SCSI_UFS_PROVISION=y