Hi Martin, All raid controllers, newer HBAs, and sas expanders do this operation in the product firmware itself and there is no mass need to have it done in libsas. In that case, Will it be good to keep this in driver itself ? Regards, Viswas G > -----Original Message----- > From: Martin K. Petersen <martin.petersen@xxxxxxxxxx> > Sent: Wednesday, September 2, 2020 6:51 AM > To: Viswas G <Viswas.G@xxxxxxxxxxxxxxxxx> > Cc: linux-scsi@xxxxxxxxxxxxxxx; Vasanthalakshmi Tharmarajan - I30664 > <Vasanthalakshmi.Tharmarajan@xxxxxxxxxxxxx>; Viswas G - I30667 > <Viswas.G@xxxxxxxxxxxxx>; Deepak Ukey - I31172 > <Deepak.Ukey@xxxxxxxxxxxxx>; martin.petersen@xxxxxxxxxx; > yuuzheng@xxxxxxxxxx; auradkar@xxxxxxxxxx; vishakhavc@xxxxxxxxxx; > bjashnani@xxxxxxxxxx; radha@xxxxxxxxxx; akshatzen@xxxxxxxxxx > Subject: Re: [PATCH v8 2/2] pm80xx : Staggered spin up support. > > EXTERNAL EMAIL: Do not click links or open attachments unless you know > the content is safe > > Viswas, > > > As a part of drive discovery, driver will initaite the drive spin up. > > If all drives do spin up together, it will result in large power > > consumption. To reduce the power consumption, driver provide an option > > to make a small group of drives (say 3 or 4 drives together) to do the > > spin up. The delay between two spin up group and no of drives to spin > > up (group) can be programmed by the customer in seeprom and driver > > will use it to control the spinup. > > Please implement this in libsas as several people have suggested. > Thanks! > > -- > Martin K. Petersen Oracle Linux Engineering
