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

[Sayali Lokhande]

Hi Evan,


On 10/3/2018 11:31 PM, Evan Green wrote:
> On Sun, Sep 23, 2018 at 11:29 PM Sayali Lokhande <sayalil@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx>
> > ---
> >   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