This is a note to let you know that I've just added the patch titled scsi: arcmsr: Fix doorbell status being updated late on ARC-1886 to the 5.13-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-arcmsr-fix-doorbell-status-being-updated-late-o.patch and it can be found in the queue-5.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2aa51911480308e96a5681c1cf4a71badc11512d Author: ching Huang <ching2048@xxxxxxxxxxxx> Date: Thu May 20 14:55:15 2021 +0800 scsi: arcmsr: Fix doorbell status being updated late on ARC-1886 [ Upstream commit d9a231226f28261a787535e08d0c78669e1ad010 ] It is possible for the IOP to be delayed in updating the doorbell status. The doorbell status should not be 0 so loop until the value changes. Link: https://lore.kernel.org/r/afdfdf7eabecf14632492c4987a6b9ac6312a7ad.camel@xxxxxxxxxxxx Signed-off-by: ching Huang <ching2048@xxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c index 930972cda38c..42e494a7106c 100644 --- a/drivers/scsi/arcmsr/arcmsr_hba.c +++ b/drivers/scsi/arcmsr/arcmsr_hba.c @@ -2419,10 +2419,17 @@ static void arcmsr_hbaD_doorbell_isr(struct AdapterControlBlock *pACB) static void arcmsr_hbaE_doorbell_isr(struct AdapterControlBlock *pACB) { - uint32_t outbound_doorbell, in_doorbell, tmp; + uint32_t outbound_doorbell, in_doorbell, tmp, i; struct MessageUnit_E __iomem *reg = pACB->pmuE; - in_doorbell = readl(®->iobound_doorbell); + if (pACB->adapter_type == ACB_ADAPTER_TYPE_F) { + for (i = 0; i < 5; i++) { + in_doorbell = readl(®->iobound_doorbell); + if (in_doorbell != 0) + break; + } + } else + in_doorbell = readl(®->iobound_doorbell); outbound_doorbell = in_doorbell ^ pACB->in_doorbell; do { writel(0, ®->host_int_status); /* clear interrupt */