The driver retries certain register reads for 3 times if the returned value is 0, this was done based on hardware specification where the controller could possibly return 0 for certain registers when there is a parallel access to some of other registers from the firmware due to BMC out of band interactions.Recently it is observed that in certain systems with increased BMC interactions, the values returned are 0 even for 3 retries (the proper value is returned between 4 to 6 retries).Hence this patch changes the retry count 3 to 30, which is a revised recommendation, to avoid the out of band conflict.

Fixes: b899202901a8 ("mpt3sas: Add separate function for aero doorbell reads") Cc: stable@vger.kernel.org Signed-off-by: Ranjan Kumar ranjan.kumar@broadcom.com --- drivers/scsi/mpt3sas/mpt3sas_base.c | 46 +++++++++++++++++++++-------- drivers/scsi/mpt3sas/mpt3sas_base.h | 1 + 2 files changed, 34 insertions(+), 13 deletions(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c index 53f5492579cb..5284584e4cd2 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.c +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c @@ -138,6 +138,9 @@ _base_get_ioc_facts(struct MPT3SAS_ADAPTER *ioc); static void _base_clear_outstanding_commands(struct MPT3SAS_ADAPTER *ioc);

+static u32 +_base_readl_ext_retry(const volatile void __iomem *addr); + /** * mpt3sas_base_check_cmd_timeout - Function * to check timeout and command termination due @@ -213,6 +216,20 @@ _base_readl_aero(const volatile void __iomem *addr) return ret_val; }

+static u32 +_base_readl_ext_retry(const volatile void __iomem *addr) +{ + u32 i, ret_val; + + for (i = 0 ; i < 30 ; i++) { + ret_val = readl(addr); + if (ret_val == 0) + continue; + } + + return ret_val; +} + static inline u32 _base_readl(const volatile void __iomem *addr) { @@ -940,7 +957,7 @@ mpt3sas_halt_firmware(struct MPT3SAS_ADAPTER *ioc)

dump_stack();

- doorbell = ioc->base_readl(&ioc->chip->Doorbell); + doorbell = ioc->base_readl_ext_retry(&ioc->chip->Doorbell); if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT) { mpt3sas_print_fault_code(ioc, doorbell & MPI2_DOORBELL_DATA_MASK); @@ -6686,7 +6703,7 @@ mpt3sas_base_get_iocstate(struct MPT3SAS_ADAPTER *ioc, int cooked) { u32 s, sc;

- s = ioc->base_readl(&ioc->chip->Doorbell); + s = ioc->base_readl_ext_retry(&ioc->chip->Doorbell); sc = s & MPI2_IOC_STATE_MASK; return cooked ? sc : s; } @@ -6831,7 +6848,7 @@ _base_wait_for_doorbell_ack(struct MPT3SAS_ADAPTER *ioc, int timeout) __func__, count, timeout)); return 0; } else if (int_status & MPI2_HIS_IOC2SYS_DB_STATUS) { - doorbell = ioc->base_readl(&ioc->chip->Doorbell); + doorbell = ioc->base_readl_ext_retry(&ioc->chip->Doorbell); if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT) { mpt3sas_print_fault_code(ioc, doorbell); @@ -6871,7 +6888,7 @@ _base_wait_for_doorbell_not_used(struct MPT3SAS_ADAPTER *ioc, int timeout) count = 0; cntdn = 1000 * timeout; do { - doorbell_reg = ioc->base_readl(&ioc->chip->Doorbell); + doorbell_reg = ioc->base_readl_ext_retry(&ioc->chip->Doorbell); if (!(doorbell_reg & MPI2_DOORBELL_USED)) { dhsprintk(ioc, ioc_info(ioc, "%s: successful count(%d), timeout(%d)\n", @@ -7019,7 +7036,7 @@ _base_handshake_req_reply_wait(struct MPT3SAS_ADAPTER *ioc, int request_bytes, __le32 *mfp;

/* make sure doorbell is not in use */ - if ((ioc->base_readl(&ioc->chip->Doorbell) & MPI2_DOORBELL_USED)) { + if ((ioc->base_readl_ext_retry(&ioc->chip->Doorbell) & MPI2_DOORBELL_USED)) { ioc_err(ioc, "doorbell is in use (line=%d)\n", __LINE__); return -EFAULT; } @@ -7068,7 +7085,7 @@ _base_handshake_req_reply_wait(struct MPT3SAS_ADAPTER *ioc, int request_bytes, }

/* read the first two 16-bits, it gives the total length of the reply */ - reply[0] = le16_to_cpu(ioc->base_readl(&ioc->chip->Doorbell) + reply[0] = le16_to_cpu(ioc->base_readl_ext_retry(&ioc->chip->Doorbell) & MPI2_DOORBELL_DATA_MASK); writel(0, &ioc->chip->HostInterruptStatus); if ((_base_wait_for_doorbell_int(ioc, 5))) { @@ -7076,7 +7093,7 @@ _base_handshake_req_reply_wait(struct MPT3SAS_ADAPTER *ioc, int request_bytes, __LINE__); return -EFAULT; } - reply[1] = le16_to_cpu(ioc->base_readl(&ioc->chip->Doorbell) + reply[1] = le16_to_cpu(ioc->base_readl_ext_retry(&ioc->chip->Doorbell) & MPI2_DOORBELL_DATA_MASK); writel(0, &ioc->chip->HostInterruptStatus);

@@ -7087,10 +7104,10 @@ _base_handshake_req_reply_wait(struct MPT3SAS_ADAPTER *ioc, int request_bytes, return -EFAULT; } if (i >= reply_bytes/2) /* overflow case */ - ioc->base_readl(&ioc->chip->Doorbell); + ioc->base_readl_ext_retry(&ioc->chip->Doorbell); else reply[i] = le16_to_cpu( - ioc->base_readl(&ioc->chip->Doorbell) + ioc->base_readl_ext_retry(&ioc->chip->Doorbell) & MPI2_DOORBELL_DATA_MASK); writel(0, &ioc->chip->HostInterruptStatus); } @@ -7949,7 +7966,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc) goto out; }

- host_diagnostic = ioc->base_readl(&ioc->chip->HostDiagnostic); + host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic); drsprintk(ioc, ioc_info(ioc, "wrote magic sequence: count(%d), host_diagnostic(0x%08x)\n", count, host_diagnostic)); @@ -7969,7 +7986,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER *ioc) for (count = 0; count < (300000000 / MPI2_HARD_RESET_PCIE_SECOND_READ_DELAY_MICRO_SEC); count++) {

- host_diagnostic = ioc->base_readl(&ioc->chip->HostDiagnostic); + host_diagnostic = ioc->base_readl_ext_retry(&ioc->chip->HostDiagnostic);

if (host_diagnostic == 0xFFFFFFFF) { ioc_info(ioc, @@ -8359,10 +8376,13 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc) ioc->rdpq_array_enable_assigned = 0; ioc->use_32bit_dma = false; ioc->dma_mask = 64; - if (ioc->is_aero_ioc) + if (ioc->is_aero_ioc) { ioc->base_readl = &_base_readl_aero; - else + ioc->base_readl_ext_retry = &_base_readl_ext_retry; + } else { ioc->base_readl = &_base_readl; + ioc->base_readl_ext_retry = &_base_readl; + } r = mpt3sas_base_map_resources(ioc); if (r) goto out_free_resources; diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h index 05364aa15ecd..10055c7e4a9f 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.h +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h @@ -1618,6 +1618,7 @@ struct MPT3SAS_ADAPTER { u8 diag_trigger_active; u8 atomic_desc_capable; BASE_READ_REG base_readl; + BASE_READ_REG base_readl_ext_retry; struct SL_WH_MASTER_TRIGGER_T diag_trigger_master; struct SL_WH_EVENT_TRIGGERS_T diag_trigger_event; struct SL_WH_SCSI_TRIGGERS_T diag_trigger_scsi;