AMD IOMMU requires IntCapXT registers to be setup in order to generate
its own interrupts (for Event Log, PPR Log, and GA Log) with 32-bit
APIC destination ID. Without this support, AMD IOMMU MSI interrupts
will not be routed correctly when booting the system in X2APIC mode.
Cc: Joerg Roedel <j...@8bytes.org>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
drivers/iommu/amd_iommu_init.c | 90 +++++++++++++++++++++++++++++++++++++++++
drivers/iommu/amd_iommu_types.h | 9 +++++
2 files changed, 99 insertions(+)
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index ff40ba7..a4c5b1e 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -35,6 +35,8 @@
#include <linux/mem_encrypt.h>
#include <asm/pci-direct.h>
#include <asm/iommu.h>
+#include <asm/apic.h>
+#include <asm/msidef.h>
#include <asm/gart.h>
#include <asm/x86_init.h>
#include <asm/iommu_table.h>
@@ -1935,6 +1937,90 @@ static int iommu_setup_msi(struct amd_iommu *iommu)
return 0;
}
+#define XT_INT_DEST_MODE(x) (((x) & 0x1ULL) << 2)
+#define XT_INT_DEST_LO(x) (((x) & 0xFFFFFFULL) << 8)
+#define XT_INT_VEC(x) (((x) & 0xFFULL) << 32)
+#define XT_INT_DEST_HI(x) ((((x) >> 24) & 0xFFULL) << 56)
+
+/**
+ * Setup the IntCapXT registers with interrupt routing information
+ * based on the PCI MSI capability block registers, accessed via
+ * MMIO MSI address low/hi and MSI data registers.
+ */
+static void iommu_update_intcapxt(struct amd_iommu *iommu)
+{
+ u64 val;
+ u32 addr_lo = readl(iommu->mmio_base + MMIO_MSI_ADDR_LO_OFFSET);
+ u32 addr_hi = readl(iommu->mmio_base + MMIO_MSI_ADDR_HI_OFFSET);
+ u32 data = readl(iommu->mmio_base + MMIO_MSI_DATA_OFFSET);
+ bool dm = (addr_lo >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;
+ u32 dest = ((addr_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xFF);
+
+ if (x2apic_enabled())
+ dest |= MSI_ADDR_EXT_DEST_ID(addr_hi);
+
+ val = XT_INT_VEC(data & 0xFF) |
+ XT_INT_DEST_MODE(dm) |
+ XT_INT_DEST_LO(dest) |
+ XT_INT_DEST_HI(dest);
+
+ /**
+ * Current IOMMU implemtation uses the same IRQ for all
+ * 3 IOMMU interrupts.
+ */
+ writeq(val, iommu->mmio_base + MMIO_INTCAPXT_EVT_OFFSET);
+ writeq(val, iommu->mmio_base + MMIO_INTCAPXT_PPR_OFFSET);
+ writeq(val, iommu->mmio_base + MMIO_INTCAPXT_GALOG_OFFSET);
+}
+
+static void _irq_notifier_notify(struct irq_affinity_notify *notify,
+ const cpumask_t *mask)
+{
+ struct amd_iommu *iommu;
+
+ for_each_iommu(iommu) {
+ if (iommu->dev->irq == notify->irq) {
+ iommu_update_intcapxt(iommu);
+ break;
+ }
+ }
+}
+
+static void _irq_notifier_release(struct kref *ref)
+{
+}
+
+static int iommu_init_intcapxt(struct amd_iommu *iommu)
+{
+ int ret;
+ struct irq_affinity_notify *notify = &iommu->intcapxt_notify;
+
+ /**
+ * IntCapXT requires XTSup=1, which can be inferred
+ * amd_iommu_xt_mode.
+ */
+ if (amd_iommu_xt_mode != IRQ_REMAP_X2APIC_MODE)
+ return 0;
+
+ /**
+ * Also, we need to setup notifier to update the IntCapXT registers
+ * whenever the irq affinity is changed from user-space.
+ */
+ notify->irq = iommu->dev->irq;
+ notify->notify = _irq_notifier_notify,
+ notify->release = _irq_notifier_release,
+ ret = irq_set_affinity_notifier(iommu->dev->irq, notify);
+ if (ret) {
+ pr_err("Failed to register irq affinity notifier (devid=%#x,
irq %d)\n",
+ iommu->devid, iommu->dev->irq);
+ return ret;
+ }
+
+ iommu_update_intcapxt(iommu);
+ iommu_feature_enable(iommu, CONTROL_INTCAPXT_EN);
+ return ret;
+}
+
static int iommu_init_msi(struct amd_iommu *iommu)
{
int ret;
@@ -1951,6 +2037,10 @@ static int iommu_init_msi(struct amd_iommu *iommu)
return ret;
enable_faults:
+ ret = iommu_init_intcapxt(iommu);
+ if (ret)
+ return ret;
+
iommu_feature_enable(iommu, CONTROL_EVT_INT_EN);
if (iommu->ppr_log != NULL)
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 87965e4..39be804f 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -72,6 +72,12 @@
#define MMIO_PPR_LOG_OFFSET 0x0038
#define MMIO_GA_LOG_BASE_OFFSET 0x00e0
#define MMIO_GA_LOG_TAIL_OFFSET 0x00e8
+#define MMIO_MSI_ADDR_LO_OFFSET 0x015C
+#define MMIO_MSI_ADDR_HI_OFFSET 0x0160
+#define MMIO_MSI_DATA_OFFSET 0x0164
+#define MMIO_INTCAPXT_EVT_OFFSET 0x0170
+#define MMIO_INTCAPXT_PPR_OFFSET 0x0178
+#define MMIO_INTCAPXT_GALOG_OFFSET 0x0180
#define MMIO_CMD_HEAD_OFFSET 0x2000
#define MMIO_CMD_TAIL_OFFSET 0x2008
#define MMIO_EVT_HEAD_OFFSET 0x2010
@@ -162,6 +168,7 @@
#define CONTROL_GALOG_EN 0x1CULL
#define CONTROL_GAINT_EN 0x1DULL
#define CONTROL_XT_EN 0x32ULL
+#define CONTROL_INTCAPXT_EN 0x33ULL
#define CTRL_INV_TO_MASK (7 << CONTROL_INV_TIMEOUT)
#define CTRL_INV_TO_NONE 0
@@ -604,6 +611,8 @@ struct amd_iommu {
/* DebugFS Info */
struct dentry *debugfs;
#endif
+ /* IRQ notifier for IntCapXT interrupt */
+ struct irq_affinity_notify intcapxt_notify;
};
static inline struct amd_iommu *dev_to_amd_iommu(struct device *dev)
--
1.8.3.1
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