From de3c9e7c784d6ba95553813b17264f1ccec48e21 Mon Sep 17 00:00:00 2001 From: Venkat Gopalakrishnan Date: Thu, 8 Dec 2016 12:38:34 -0800 Subject: [PATCH] scsi: ufs: make sure all interrupts are processed As multiple requests are submitted to the ufs host controller in parallel there could be instances where the command completion interrupt arrives later for a request that is already processed earlier as the corresponding doorbell was cleared when handling the previous interrupt. Read the interrupt status in a loop after processing the received interrupt to catch such interrupts and handle it. Change-Id: I91c1ba3360592f258a2c3c4e902394c3ddc77bca Signed-off-by: Venkat Gopalakrishnan --- drivers/scsi/ufs/ufshcd.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 06defae6d5ba..902a58f0c70f 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6134,19 +6134,30 @@ static irqreturn_t ufshcd_intr(int irq, void *__hba) u32 intr_status, enabled_intr_status; irqreturn_t retval = IRQ_NONE; struct ufs_hba *hba = __hba; + int retries = hba->nutrs; spin_lock(hba->host->host_lock); intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); - enabled_intr_status = - intr_status & ufshcd_readl(hba, REG_INTERRUPT_ENABLE); - if (intr_status) - ufshcd_writel(hba, intr_status, REG_INTERRUPT_STATUS); + /* + * There could be max of hba->nutrs reqs in flight and in worst case + * if the reqs get finished 1 by 1 after the interrupt status is + * read, make sure we handle them by checking the interrupt status + * again in a loop until we process all of the reqs before returning. + */ + do { + enabled_intr_status = + intr_status & ufshcd_readl(hba, REG_INTERRUPT_ENABLE); + if (intr_status) + ufshcd_writel(hba, intr_status, REG_INTERRUPT_STATUS); + if (enabled_intr_status) { + ufshcd_sl_intr(hba, enabled_intr_status); + retval = IRQ_HANDLED; + } + + intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); + } while (intr_status && --retries); - if (enabled_intr_status) { - ufshcd_sl_intr(hba, enabled_intr_status); - retval = IRQ_HANDLED; - } spin_unlock(hba->host->host_lock); return retval; }