> From: Stanley Chu <stanley....@mediatek.com> > Sent: Monday, May 4, 2020 4:56 PM > To: linux-s...@vger.kernel.org; martin.peter...@oracle.com; > avri.alt...@wdc.com; alim.akh...@samsung.com; j...@linux.ibm.com; > asuto...@codeaurora.org > Cc: Bean Huo (beanhuo) <bean...@micron.com>; c...@codeaurora.org; > matthias....@gmail.com; bvanass...@acm.org; linux- > media...@lists.infradead.org; linux-arm-ker...@lists.infradead.org; linux- > ker...@vger.kernel.org; kuohong.w...@mediatek.com; > peter.w...@mediatek.com; chun-hung...@mediatek.com; > andy.t...@mediatek.com; Stanley Chu <stanley....@mediatek.com> > Subject: [EXT] [PATCH v6 6/8] scsi: ufs: add LU Dedicated buffer mode support > for WriteBooster > > According to UFS specification, there are two WriteBooster mode of > operations: "LU dedicated buffer" mode and "shared buffer" mode. > In the "LU dedicated buffer" mode, the WriteBooster Buffer is dedicated to a > logical unit. > > If the device supports the "LU dedicated buffer" mode, this mode is configured > by setting bWriteBoosterBufferType to 00h. The logical unit WriteBooster > Buffer > size is configured by setting the dLUNumWriteBoosterBufferAllocUnits field of > the related Unit Descriptor. Only a value greater than zero enables the > WriteBooster feature in the logical unit. > > Modify ufshcd_wb_probe() as above description to support LU Dedicated buffer > mode. > > Note that according to UFS 3.1 specification, the valid value of > bDeviceMaxWriteBoosterLUs parameter in Geometry Descriptor is 1, which > means at most one LUN can have WriteBooster buffer in "LU dedicated buffer > mode". Therefore this patch supports only one LUN with WriteBooster enabled. > All WriteBooster related sysfs nodes are specifically mapped to the LUN with > WriteBooster enabled in LU Dedicated buffer mode. > > Signed-off-by: Stanley Chu <stanley....@mediatek.com> > Reviewed-by: Avri Altman <avri.alt...@wdc.com> Reviewed-by: Bean Huo <bean...@micron.com>
