This is a note to let you know that I've just added the patch titled scsi: mpt3sas: Perform additional retries if doorbell read returns 0 to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-mpt3sas-perform-additional-retries-if-doorbell-read-returns-0.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 4ca10f3e31745d35249a727ecd108eb58f0a8c5e Mon Sep 17 00:00:00 2001 From: Ranjan Kumar <ranjan.kumar@xxxxxxxxxxxx> Date: Tue, 29 Aug 2023 14:30:19 +0530 Subject: scsi: mpt3sas: Perform additional retries if doorbell read returns 0 From: Ranjan Kumar <ranjan.kumar@xxxxxxxxxxxx> commit 4ca10f3e31745d35249a727ecd108eb58f0a8c5e upstream. The driver retries certain register reads 3 times if the returned value is 0. This was done because the controller could return 0 for certain registers if other registers were being accessed concurrently by the BMC. In certain systems with increased BMC interactions, the register values returned can be 0 for longer than 3 retries. Change the retry count from 3 to 30 for the affected registers to prevent problems with out-of-band management. Fixes: b899202901a8 ("scsi: mpt3sas: Add separate function for aero doorbell reads") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ranjan Kumar <ranjan.kumar@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230829090020.5417-2-ranjan.kumar@xxxxxxxxxxxx Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/mpt3sas/mpt3sas_base.c | 46 +++++++++++++++++++++++++----------- drivers/scsi/mpt3sas/mpt3sas_base.h | 1 2 files changed, 34 insertions(+), 13 deletions(-) --- a/drivers/scsi/mpt3sas/mpt3sas_base.c +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c @@ -131,6 +131,9 @@ _base_get_ioc_facts(struct MPT3SAS_ADAPT 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 @@ -206,6 +209,20 @@ _base_readl_aero(const volatile void __i 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) { @@ -861,7 +878,7 @@ mpt3sas_halt_firmware(struct MPT3SAS_ADA 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); @@ -5667,7 +5684,7 @@ mpt3sas_base_get_iocstate(struct MPT3SAS { 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; } @@ -5812,7 +5829,7 @@ _base_wait_for_doorbell_ack(struct MPT3S __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); @@ -5852,7 +5869,7 @@ _base_wait_for_doorbell_not_used(struct 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", @@ -5989,7 +6006,7 @@ _base_handshake_req_reply_wait(struct MP __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; } @@ -6038,7 +6055,7 @@ _base_handshake_req_reply_wait(struct MP } /* 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))) { @@ -6046,7 +6063,7 @@ _base_handshake_req_reply_wait(struct MP __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); @@ -6057,10 +6074,10 @@ _base_handshake_req_reply_wait(struct MP 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); } @@ -6906,7 +6923,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER 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)); @@ -6926,7 +6943,7 @@ _base_diag_reset(struct MPT3SAS_ADAPTER 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, @@ -7313,10 +7330,13 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPT 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; --- a/drivers/scsi/mpt3sas/mpt3sas_base.h +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h @@ -1469,6 +1469,7 @@ 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; Patches currently in stable-queue which might be from ranjan.kumar@xxxxxxxxxxxx are queue-5.10/scsi-mpt3sas-perform-additional-retries-if-doorbell-read-returns-0.patch