[Qemu-devel] [V1 2/4] hw/iommu: AMD IOMMU interrupt remapping

[David Kiarie]

Introduce AMD IOMMU interrupt remapping and hook it onto
the existing interrupt remapping infrastructure

Signed-off-by: David Kiarie <address@hidden>
---
 hw/i386/amd_iommu.c | 226 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 hw/i386/amd_iommu.h |   2 +
 2 files changed, 227 insertions(+), 1 deletion(-)

diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 5fab9aa..825159b 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -18,12 +18,14 @@
  * with this program; if not, see <http://www.gnu.org/licenses/>.
  *
  * Cache implementation inspired by hw/i386/intel_iommu.c
+ *
  */
 #include "qemu/osdep.h"
 #include <math.h>
 #include "hw/pci/msi.h"
 #include "hw/i386/pc.h"
 #include "hw/i386/amd_iommu.h"
+#include "hw/i386/ioapic_internal.h"
 #include "hw/pci/pci_bus.h"
 #include "trace.h"
 
@@ -660,6 +662,11 @@ static void amdvi_inval_inttable(AMDVIState *s, 
CMDInvalIntrTable *inval)
         amdvi_log_illegalcom_error(s, inval->type, s->cmdbuf + s->cmdbuf_head);
         return;
     }
+
+    if (s->ir_cache) {
+        x86_iommu_iec_notify_all(X86_IOMMU_DEVICE(s), true, 0, 0);
+    }
+
     trace_amdvi_intr_inval();
 }
 
@@ -1221,6 +1228,207 @@ static IOMMUTLBEntry amdvi_translate(MemoryRegion 
*iommu, hwaddr addr,
     return ret;
 }
 
+static inline int amdvi_ir_pass(MSIMessage *src, MSIMessage *dst, uint8_t bit,
+                                uint64_t dte)
+{
+    if ((dte & (1UL << bit))) {
+        /* passing interrupt enabled */
+        dst->address = src->address;
+        dst->data = src->data;
+    } else {
+        /* should be target aborted */
+        return -AMDVI_TARGET_ABORT;
+    }
+    return 0;
+}
+
+static int amdvi_remap_ir_intctl(uint64_t dte, uint32_t irte,
+                                 MSIMessage *src, MSIMessage *dst)
+{
+    int ret = 0;
+
+    switch ((dte >> AMDVI_DTE_INTCTL ) & 3UL) {
+    case 1:
+        /* pass */
+        memcpy(dst, src, sizeof(*dst));
+        break;
+    case 2:
+        /* remap */
+        if (irte & AMDVI_IRTE_REMAP_MASK) {
+            /* LOCAL APIC address */
+            dst->address = AMDVI_LOCAL_APIC_ADDR;
+            /* destination mode */
+            dst->address |= (((irte & AMDVI_IRTE_DM_MASK) >> 6) <<
+                    AMDVI_MSI_ADDR_DM_RSHIFT);
+            /* RH */
+            dst->address |= ((irte & AMDVI_IRTE_RQEOI_MASK) >> 5) <<
+                AMDVI_MSI_ADDR_RH_RSHIFT;
+            /* Destination ID */
+            dst->address |= ((irte & AMDVI_IRTE_DEST_MASK) >> 8) <<
+                AMDVI_MSI_ADDR_DEST_RSHIFT;
+            /* construct data - vector */
+            dst->data |= (irte & AMDVI_IRTE_VECTOR_MASK) >> 16;
+            /* Interrupt type */
+            dst->data |= ((irte & AMDVI_IRTE_INTTYPE_MASK) >> 2) <<
+                AMDVI_MSI_DATA_DM_RSHIFT;
+        } else  {
+            ret = -AMDVI_TARGET_ABORT;
+        }
+        break;
+    case 0:
+    case 3:
+    default:
+        ret = -AMDVI_TARGET_ABORT;
+    }
+    return ret;
+}
+/*
+ * We don't support guest virtual APIC so IRTE size will most likely always be 
4
+ */
+static int amdvi_irte_get(AMDVIState *s, MSIMessage *src, uint32_t *irte,
+                          uint64_t *dte, uint16_t devid)
+{
+    uint64_t irte_root, offset = devid * AMDVI_DEVTAB_ENTRY_SIZE,
+             irte_size = AMDVI_DEFAULT_IRTE_SIZE,
+             ir_table_size;
+
+    /* check for GASup and if it's enabled */
+    if ((amdvi_readq(s, AMDVI_EXT_FEATURES) & AMDVI_GASUP)
+        && (amdvi_readq(s, AMDVI_MMIO_CONTROL) & AMDVI_GAEN)) {
+        /* set a different IRTE size */
+        irte_size = AMDVI_IRTE_SIZE_GASUP;
+    }
+    if (dma_memory_read(&address_space_memory, s->devtab + offset, dte,
+                        AMDVI_DEVTAB_ENTRY_SIZE)) {
+        trace_amdvi_dte_get_fail(s->devtab, offset);
+        return -AMDVI_DEV_TAB_HW;
+    }
+
+    irte_root = dte[2] & AMDVI_IRTEROOT_MASK;
+    offset = (src->data & AMDVI_IRTE_INDEX_MASK) << 2;
+    ir_table_size = pow(2, dte[2] & AMDVI_IR_TABLE_SIZE_MASK);
+    /* enforce IR table size */
+    if (offset > (ir_table_size * irte_size)) {
+        trace_amdvi_invalid_irte_entry(offset, ir_table_size);
+        return -AMDVI_TARGET_ABORT;
+    }
+    /* read IRTE */
+    if (dma_memory_read(&address_space_memory, irte_root + offset,
+        irte, sizeof(*irte))) {
+        trace_amdvi_irte_get_fail(irte_root, offset);
+        return -AMDVI_DEV_TAB_HW;
+    }
+    return 0;
+}
+
+static int amdvi_int_remap(X86IOMMUState *iommu, MSIMessage *src,
+                           MSIMessage *dst, uint16_t sid)
+{
+    trace_amdvi_ir_request(src->data, src->address, sid);
+
+    AMDVIState *s = AMD_IOMMU_DEVICE(iommu);
+    int ret = 0;
+    uint64_t dte[4];
+    uint32_t ir_enabled, irte;
+
+    ret = amdvi_irte_get(s, src, &irte, dte, sid);
+    if (ret < 0) {
+        goto no_remap;
+    }
+    /* interrupt remapping disabled */
+    if (!(dte[2] & AMDVI_IR_VALID)) {
+        memcpy(dst, src, sizeof(*src));
+        return ret;
+    }
+    switch (src->data & AMDVI_IR_TYPE_MASK) {
+    case AMDVI_MT_FIXED:
+    case AMDVI_MT_ARBIT:
+        ret = amdvi_remap_ir_intctl(dte[2], irte, src, dst);
+        if (ret < 0) {
+            goto no_remap;
+        } else {
+            s->ir_cache = true;
+            trace_amdvi_ir_remap(dst->data, dst->address, sid);
+            return ret;
+        }
+    /* not handling SMI currently */
+    case AMDVI_MT_SMI:
+        goto no_remap;
+    case AMDVI_MT_NMI:
+        ir_enabled = AMDVI_DTE_NMIPASS;
+        break;
+    case AMDVI_MT_INIT:
+        ir_enabled = AMDVI_DTE_INTPASS;
+        break;
+    case AMDVI_MT_EXTINT:
+        ir_enabled = AMDVI_DTE_EINTPASS;
+        break;
+    case AMDVI_MT_LINT1:
+        ir_enabled = AMDVI_DTE_LINT1PASS;
+        break;
+    case AMDVI_MT_LINT0:
+        ir_enabled = AMDVI_DTE_LINT0PASS;
+    }
+
+    ret = amdvi_ir_pass(src, dst, ir_enabled, dte[2]);
+    if (ret < 0){
+        goto no_remap;
+    }
+    s->ir_cache = true;
+    trace_amdvi_ir_remap(dst->data, dst->address, sid);
+    return ret;
+no_remap:
+    memcpy(dst, src, sizeof(*src));
+    trace_amdvi_ir_target_abort(dst->data, dst->address, sid);
+    return ret;
+}
+
+static MemTxResult amdvi_ir_read(void *opaque, hwaddr addr,
+                                 uint64_t *data, unsigned size,
+                                 MemTxAttrs attrs)
+{
+    return MEMTX_OK;
+}
+
+static MemTxResult amdvi_ir_write(void *opaque, hwaddr addr, uint64_t val,
+                                  unsigned size, MemTxAttrs attrs)
+{
+    AMDVIAddressSpace *as = opaque;
+    MSIMessage from = { addr + AMDVI_INT_ADDR_FIRST, val }, to = { 0, 0};
+    uint16_t sid = PCI_BUILD_BDFi(as->bus_num, as->devfn);
+    int ret = 0;
+
+    ret  = amdvi_int_remap(X86_IOMMU_DEVICE(as->iommu_state), &from, &to,
+                           attrs.requester_id);
+
+    if (ret < 0) {
+        trace_amdvi_ir_target_abort(from.data, from.address,
+                                    attrs.requester_id);
+        return MEMTX_ERROR;
+    }
+
+    if(dma_memory_write(&address_space_memory, to.address, &to.data, size)) {
+        trace_amdvi_ir_write_fail(to.address, to.data);
+        return MEMTX_ERROR;
+    }
+
+    return MEMTX_OK;
+}
+
+static const MemoryRegionOps amdvi_ir_ops = {
+    .read_with_attrs = amdvi_ir_read,
+    .write_with_attrs = amdvi_ir_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    }
+};
+
 static AddressSpace *amdvi_host_dma_iommu(PCIBus *bus, void *opaque, int devfn)
 {
     AMDVIState *s = opaque;
@@ -1244,6 +1452,12 @@ static AddressSpace *amdvi_host_dma_iommu(PCIBus *bus, 
void *opaque, int devfn)
 
         memory_region_init_iommu(&iommu_as[devfn]->iommu, OBJECT(s),
                                  &s->iommu_ops, "amd-iommu", UINT64_MAX);
+        memory_region_init_io(&iommu_as[devfn]->iommu_ir, OBJECT(s),
+                              &amdvi_ir_ops, iommu_as[devfn], "amd-iommu-ir",
+                              AMDVI_INT_ADDR_SIZE);
+        memory_region_add_subregion(&iommu_as[devfn]->iommu,
+                                    AMDVI_INT_ADDR_FIRST,
+                                    &iommu_as[devfn]->iommu_ir);
         address_space_init(&iommu_as[devfn]->as, &iommu_as[devfn]->iommu,
                            "amd-iommu");
     }
@@ -1292,6 +1506,7 @@ static void amdvi_init(AMDVIState *s)
     s->enabled = false;
     s->ats_enabled = false;
     s->cmdbuf_enabled = false;
+    s->ir_cache = false;
 
     /* reset MMIO */
     memset(s->mmior, 0, AMDVI_MMIO_SIZE);
@@ -1331,11 +1546,15 @@ static void amdvi_realize(DeviceState *dev, Error **err)
     AMDVIState *s = AMD_IOMMU_DEVICE(dev);
     X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
     PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;
+    PCMachineState *pcms = PC_MACHINE(qdev_get_machine());
     s->iotlb = g_hash_table_new_full(amdvi_uint64_hash,
                                      amdvi_uint64_equal, g_free, g_free);
 
-    /* This device should take care of IOMMU PCI properties */
+    /* AMD IOMMU has Interrupt Remapping on by default */
+    x86_iommu->intr_supported = true;
     x86_iommu->type = TYPE_AMD;
+
+    /* This device should take care of IOMMU PCI properties */
     qdev_set_parent_bus(DEVICE(&s->pci), &bus->qbus);
     object_property_set_bool(OBJECT(&s->pci), true, "realized", err);
     s->capab_offset = pci_add_capability(&s->pci.dev, AMDVI_CAPAB_ID_SEC, 0,
@@ -1347,9 +1566,13 @@ static void amdvi_realize(DeviceState *dev, Error **err)
     memory_region_init_io(&s->mmio, OBJECT(s), &mmio_mem_ops, s, "amdvi-mmio",
                           AMDVI_MMIO_SIZE);
 
+    x86_iommu->ioapic_bdf = PCI_BUILD_BDF(AMDVI_BUS_NUM,
+             AMDVI_DEVFN_IOAPIC);
+
     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->mmio);
     sysbus_mmio_map(SYS_BUS_DEVICE(s), 0, AMDVI_BASE_ADDR);
     pci_setup_iommu(bus, amdvi_host_dma_iommu, s);
+    pcms->ioapic_as = amdvi_host_dma_iommu(bus, s, AMDVI_DEVFN_IOAPIC);
     s->devid = object_property_get_int(OBJECT(&s->pci), "addr", err);
     msi_init(&s->pci.dev, 0, 1, true, false, err);
     amdvi_init(s);
@@ -1376,6 +1599,7 @@ static void amdvi_class_init(ObjectClass *klass, void* 
data)
     dc->vmsd = &vmstate_amdvi;
     dc->hotpluggable = false;
     dc_class->realize = amdvi_realize;
+    dc_class->int_remap = amdvi_int_remap;
 }
 
 static const TypeInfo amdvi = {
diff --git a/hw/i386/amd_iommu.h b/hw/i386/amd_iommu.h
index 2a7f19e..f0e23a8 100644
--- a/hw/i386/amd_iommu.h
+++ b/hw/i386/amd_iommu.h
@@ -356,6 +356,8 @@ typedef struct AMDVIState {
     uint32_t evtlog_len;         /* event log length             */
     uint32_t evtlog_head;        /* current IOMMU write position */
     uint32_t evtlog_tail;        /* current Software read position */
+    /* whether we have remapped any interrupts and hence IR cache */
+    bool ir_cache;
 
     /* unused for now */
     hwaddr excl_base;            /* base DVA - IOMMU exclusion range */
-- 
2.1.4