diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 27792f8c429d301420afd687c2137689f9c547f0..c6f3c7e046840d4b6de11c9c3c06c91e25f14431 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -700,22 +700,7 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt) static void iommu_poll_events(struct amd_iommu *iommu) { - u32 head, tail, status; - unsigned long flags; - - spin_lock_irqsave(&iommu->lock, flags); - - /* enable event interrupts again */ - do { - /* - * Workaround for Erratum ERBT1312 - * Clearing the EVT_INT bit may race in the hardware, so read - * it again and make sure it was really cleared - */ - status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); - writel(MMIO_STATUS_EVT_INT_MASK, - iommu->mmio_base + MMIO_STATUS_OFFSET); - } while (status & MMIO_STATUS_EVT_INT_MASK); + u32 head, tail; head = readl(iommu->mmio_base + MMIO_EVT_HEAD_OFFSET); tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET); @@ -726,8 +711,6 @@ static void iommu_poll_events(struct amd_iommu *iommu) } writel(head, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET); - - spin_unlock_irqrestore(&iommu->lock, flags); } static void iommu_handle_ppr_entry(struct amd_iommu *iommu, u64 *raw) @@ -752,26 +735,11 @@ static void iommu_handle_ppr_entry(struct amd_iommu *iommu, u64 *raw) static void iommu_poll_ppr_log(struct amd_iommu *iommu) { - unsigned long flags; - u32 head, tail, status; + u32 head, tail; if (iommu->ppr_log == NULL) return; - spin_lock_irqsave(&iommu->lock, flags); - - /* enable ppr interrupts again */ - do { - /* - * Workaround for Erratum ERBT1312 - * Clearing the PPR_INT bit may race in the hardware, so read - * it again and make sure it was really cleared - */ - status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); - writel(MMIO_STATUS_PPR_INT_MASK, - iommu->mmio_base + MMIO_STATUS_OFFSET); - } while (status & MMIO_STATUS_PPR_INT_MASK); - head = readl(iommu->mmio_base + MMIO_PPR_HEAD_OFFSET); tail = readl(iommu->mmio_base + MMIO_PPR_TAIL_OFFSET); @@ -807,34 +775,50 @@ static void iommu_poll_ppr_log(struct amd_iommu *iommu) head = (head + PPR_ENTRY_SIZE) % PPR_LOG_SIZE; writel(head, iommu->mmio_base + MMIO_PPR_HEAD_OFFSET); - /* - * Release iommu->lock because ppr-handling might need to - * re-acquire it - */ - spin_unlock_irqrestore(&iommu->lock, flags); - /* Handle PPR entry */ iommu_handle_ppr_entry(iommu, entry); - spin_lock_irqsave(&iommu->lock, flags); - /* Refresh ring-buffer information */ head = readl(iommu->mmio_base + MMIO_PPR_HEAD_OFFSET); tail = readl(iommu->mmio_base + MMIO_PPR_TAIL_OFFSET); } - - spin_unlock_irqrestore(&iommu->lock, flags); } irqreturn_t amd_iommu_int_thread(int irq, void *data) { - struct amd_iommu *iommu; + struct amd_iommu *iommu = (struct amd_iommu *) data; + u32 status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); - for_each_iommu(iommu) { - iommu_poll_events(iommu); - iommu_poll_ppr_log(iommu); - } + while (status & (MMIO_STATUS_EVT_INT_MASK | MMIO_STATUS_PPR_INT_MASK)) { + /* Enable EVT and PPR interrupts again */ + writel((MMIO_STATUS_EVT_INT_MASK | MMIO_STATUS_PPR_INT_MASK), + iommu->mmio_base + MMIO_STATUS_OFFSET); + if (status & MMIO_STATUS_EVT_INT_MASK) { + pr_devel("AMD-Vi: Processing IOMMU Event Log\n"); + iommu_poll_events(iommu); + } + + if (status & MMIO_STATUS_PPR_INT_MASK) { + pr_devel("AMD-Vi: Processing IOMMU PPR Log\n"); + iommu_poll_ppr_log(iommu); + } + + /* + * Hardware bug: ERBT1312 + * When re-enabling interrupt (by writing 1 + * to clear the bit), the hardware might also try to set + * the interrupt bit in the event status register. + * In this scenario, the bit will be set, and disable + * subsequent interrupts. + * + * Workaround: The IOMMU driver should read back the + * status register and check if the interrupt bits are cleared. + * If not, driver will need to go through the interrupt handler + * again and re-clear the bits + */ + status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET); + } return IRQ_HANDLED; } diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index 9767941664818f0f082ab0cf17f5e7e3ac722c38..3d3d6cd52d473e401ab73035f6a29f440afcf6d6 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1324,7 +1324,7 @@ static int iommu_setup_msi(struct amd_iommu *iommu) amd_iommu_int_handler, amd_iommu_int_thread, 0, "AMD-Vi", - iommu->dev); + iommu); if (r) { pci_disable_msi(iommu->dev);