[Qemu-arm] [RFC v5 7/7] hw/arm/virt-acpi-build: Add ITS description in ACPI MADT table

[Eric Auger <eric.auger@redhat.com>]

This patch exposes the GICv3 ITS to the ACPI guest. The ITS structure
is added to the MADT table.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v5: new

Tested with Tomasz' kernel series on guest side:
- [PATCH V7 0/8] Introduce ACPI world to ITS,
  https://lkml.org/lkml/2016/6/20/321
- for running PCIe on the guest (virtio-pci-net or vhost-net)
  the following series is also needed, although not directly ITS:
  Support for ARM64 ACPI based PCI host controller,
  https://lwn.net/Articles/690995/
---
 hw/arm/virt-acpi-build.c    |  7 +++++++
 include/hw/acpi/acpi-defs.h | 13 ++++++++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 28fc59c..6cfedff 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -546,6 +546,7 @@ build_madt(GArray *table_data, BIOSLinker *linker, VirtGuestInfo *guest_info)
     }
 
     if (guest_info->gic_version == 3) {
+        AcpiMadtGicIts *gic_its;
         AcpiMadtGenericRedistributor *gicr = acpi_data_push(table_data,
                                                          sizeof *gicr);
 
@@ -553,6 +554,12 @@ build_madt(GArray *table_data, BIOSLinker *linker, VirtGuestInfo *guest_info)
         gicr->length = sizeof(*gicr);
         gicr->base_address = cpu_to_le64(memmap[VIRT_GIC_REDIST].base);
         gicr->range_length = cpu_to_le32(memmap[VIRT_GIC_REDIST].size);
+
+        gic_its = acpi_data_push(table_data, sizeof *gic_its);
+        gic_its->type = ACPI_APIC_ITS_STRUCTURE;
+        gic_its->length = sizeof(*gic_its);
+        gic_its->gic_its_id = 0;
+        gic_its->base_address = cpu_to_le64(memmap[VIRT_GIC_ITS].base);
     } else {
         gic_msi = acpi_data_push(table_data, sizeof *gic_msi);
         gic_msi->type = ACPI_APIC_GENERIC_MSI_FRAME;
diff --git a/include/hw/acpi/acpi-defs.h b/include/hw/acpi/acpi-defs.h
index 41c1d95..ba3be1e 100644
--- a/include/hw/acpi/acpi-defs.h
+++ b/include/hw/acpi/acpi-defs.h
@@ -294,7 +294,8 @@ typedef struct AcpiMultipleApicTable AcpiMultipleApicTable;
 #define ACPI_APIC_GENERIC_DISTRIBUTOR   12
 #define ACPI_APIC_GENERIC_MSI_FRAME     13
 #define ACPI_APIC_GENERIC_REDISTRIBUTOR 14
-#define ACPI_APIC_RESERVED              15   /* 15 and greater are reserved */
+#define ACPI_APIC_ITS_STRUCTURE         15
+#define ACPI_APIC_RESERVED              16   /* 16 and greater are reserved */
 
 /*
  * MADT sub-structures (Follow MULTIPLE_APIC_DESCRIPTION_TABLE)
@@ -386,6 +387,16 @@ struct AcpiMadtGenericMsiFrame {
 
 typedef struct AcpiMadtGenericMsiFrame AcpiMadtGenericMsiFrame;
 
+struct AcpiMadtGicIts {
+    ACPI_SUB_HEADER_DEF
+    uint16_t reserved;
+    uint32_t gic_its_id;
+    uint64_t base_address;
+    uint32_t reserved2;
+} QEMU_PACKED;
+
+typedef struct AcpiMadtGicIts AcpiMadtGicIts;
+
 struct AcpiMadtGenericRedistributor {
     ACPI_SUB_HEADER_DEF
     uint16_t reserved;
-- 
2.5.5