On Mon, Apr 10, 2017 at 09:21:57PM +0800, John Garry wrote: > From: Xiaofei Tan <tanxiaofei@xxxxxxxxxx> > > This patch provides a workaround a SoC bug where SATA IPTTs for > different devices may conflict. > > The workaround solution requests the following: > 1. SATA device id must be even and not equal to SAS IPTT. > 2. SATA device can not share the same IPTT with other SAS or > SATA device. > > Besides we shall consider IPTT value 0 is reserved for another SoC > bug (STP device open link at firstly after SAS controller reset). > > To sum up, the solution is: > Each SATA device uses independent and continuous 32 even IPTT from > 64 to 4094, then v2 hw can only support 63 SATA devices. > All SAS device(SSP/SMP devices) share odd IPTT value from 1 to > 4095. > > Signed-off-by: Xiaofei Tan <tanxiaofei@xxxxxxxxxx> > Signed-off-by: John Garry <john.garry@xxxxxxxxxx> > --- Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx> -- Johannes Thumshirn Storage jthumshirn@xxxxxxx +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
