Problem statement: Sometimes aero controllers appears to be returning bad data (0) for doorbell register read and if retries are performed immediately after the bad read, they return good data. Fix: In below four patches added workaround to retry read operation from controller doorbell registers for maximum three times, if read returns zero. Suganath Prabu (4): mpt3sas: Introduce flag for aero based controllers. mpt3sas: Add separate function for aero doorbell reads. mpt3sas: Replace readl with ioc->base_readl. mpt3sas: Update driver version to 27.101.00.00. drivers/scsi/mpt3sas/mpt3sas_base.c | 69 ++++++++++++++++++++++++++---------- drivers/scsi/mpt3sas/mpt3sas_base.h | 7 ++-- drivers/scsi/mpt3sas/mpt3sas_scsih.c | 14 ++++---- 3 files changed, 63 insertions(+), 27 deletions(-) -- 1.8.3.1