intel-iommu: set compatibility format interrupt
When extended interrupt mode (x2apic mode) is not supported in a
system, it must set compatibility format interrupt to bypass
interrupt remapping, otherwise compatibility format interrupts
will be blocked.
This will be used when interrupt remapping is enabled while x2apic
is not supported.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index c26633d..ef25caa 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -415,12 +415,27 @@
/* Set interrupt-remapping table pointer */
cmd = iommu->gcmd | DMA_GCMD_SIRTP;
+ iommu->gcmd |= DMA_GCMD_SIRTP;
writel(cmd, iommu->reg + DMAR_GCMD_REG);
IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
readl, (sts & DMA_GSTS_IRTPS), sts);
spin_unlock_irqrestore(&iommu->register_lock, flags);
+ if (mode == 0) {
+ spin_lock_irqsave(&iommu->register_lock, flags);
+
+ /* enable comaptiblity format interrupt pass through */
+ cmd = iommu->gcmd | DMA_GCMD_CFI;
+ iommu->gcmd |= DMA_GCMD_CFI;
+ writel(cmd, iommu->reg + DMAR_GCMD_REG);
+
+ IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+ readl, (sts & DMA_GSTS_CFIS), sts);
+
+ spin_unlock_irqrestore(&iommu->register_lock, flags);
+ }
+
/*
* global invalidation of interrupt entry cache before enabling
* interrupt-remapping.
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 3771cd1..aa8c531 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -164,6 +164,7 @@
#define DMA_GCMD_QIE (((u32)1) << 26)
#define DMA_GCMD_SIRTP (((u32)1) << 24)
#define DMA_GCMD_IRE (((u32) 1) << 25)
+#define DMA_GCMD_CFI (((u32) 1) << 23)
/* GSTS_REG */
#define DMA_GSTS_TES (((u32)1) << 31)
@@ -174,6 +175,7 @@
#define DMA_GSTS_QIES (((u32)1) << 26)
#define DMA_GSTS_IRTPS (((u32)1) << 24)
#define DMA_GSTS_IRES (((u32)1) << 25)
+#define DMA_GSTS_CFIS (((u32)1) << 23)
/* CCMD_REG */
#define DMA_CCMD_ICC (((u64)1) << 63)