[Qemu-devel] [PATCH 9/9] hw/arm/virt: Add virt-3.0 machine type

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

This machine type supports two new features:
- highmem 256MB ECAM (default). This feature is disabled for
  earlier machine types and if highmem is off.
- max_cpus set to 512 vcpus (255 before)

The high 256MB ECAM region is chosen instead of the legacy
16MB one if the machine type allows it, if highmem is set
(LPAE supported by the guest) and (!firmware_loaded || aarch64).
Indeed aarch32 mode FW may not support this high ECAM region.

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

---

PATCH: merge of ECAM and VCPU extension
- Laszlo reviewed the ECAM changes but I dropped his R-b
  due to the squash

RFC -> v1
- check firmware_loaded and aarch64 value
- do all the computation in machvirt_init
---
 hw/arm/virt.c         | 36 ++++++++++++++++++++++++++++++------
 include/hw/arm/virt.h |  1 +
 2 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 22b9bd1..5ed25b4 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1317,6 +1317,7 @@ static void machvirt_init(MachineState *machine)
     int n, virt_max_cpus;
     MemoryRegion *ram = g_new(MemoryRegion, 1);
     bool firmware_loaded = bios_name || drive_get(IF_PFLASH, 0, 0);
+    bool aarch64 = true;
 
     /* We can probe only here because during property set
      * KVM is not available yet
@@ -1432,6 +1433,8 @@ static void machvirt_init(MachineState *machine)
         numa_cpu_pre_plug(&possible_cpus->cpus[cs->cpu_index], DEVICE(cpuobj),
                           &error_fatal);
 
+        aarch64 &= object_property_get_bool(cpuobj, "aarch64", NULL);
+
         if (!vms->secure) {
             object_property_set_bool(cpuobj, false, "has_el3", NULL);
         }
@@ -1490,6 +1493,8 @@ static void machvirt_init(MachineState *machine)
         create_uart(vms, pic, VIRT_SECURE_UART, secure_sysmem, serial_hd(1));
     }
 
+    vms->highmem_ecam &= vms->highmem && (!firmware_loaded || aarch64);
+
     create_rtc(vms, pic);
 
     create_pcie(vms, pic);
@@ -1700,11 +1705,13 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
 
     mc->init = machvirt_init;
-    /* Start max_cpus at the maximum QEMU supports. We'll further restrict
-     * it later in machvirt_init, where we have more information about the
-     * configuration of the particular instance.
+    /* Start with max_cpus set to 512. This value is chosen since achievable
+     * in accelerated mode with GICv3 and recent host supporting up to 512 vcpus
+     * and multiple redistributor region registration.
+     * This value will be refined later on once we collect more information
+     * about the configuration of the particular instance.
      */
-    mc->max_cpus = 255;
+    mc->max_cpus = 512;
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_CALXEDA_XGMAC);
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_AMD_XGBE);
     mc->block_default_type = IF_VIRTIO;
@@ -1743,7 +1750,7 @@ type_init(machvirt_machine_init);
 #define VIRT_COMPAT_2_12 \
     HW_COMPAT_2_12
 
-static void virt_2_12_instance_init(Object *obj)
+static void virt_3_0_instance_init(Object *obj)
 {
     VirtMachineState *vms = VIRT_MACHINE(obj);
     VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(vms);
@@ -1786,6 +1793,8 @@ static void virt_2_12_instance_init(Object *obj)
                                     "Set GIC version. "
                                     "Valid values are 2, 3 and host", NULL);
 
+    vms->highmem_ecam = !vmc->no_highmem_ecam;
+
     if (vmc->no_its) {
         vms->its = false;
     } else {
@@ -1811,11 +1820,26 @@ static void virt_2_12_instance_init(Object *obj)
     vms->irqmap = a15irqmap;
 }
 
+static void virt_machine_3_0_options(MachineClass *mc)
+{
+}
+DEFINE_VIRT_MACHINE_AS_LATEST(3, 0)
+
+static void virt_2_12_instance_init(Object *obj)
+{
+    virt_3_0_instance_init(obj);
+}
+
 static void virt_machine_2_12_options(MachineClass *mc)
 {
+    VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc));
+
+    virt_machine_3_0_options(mc);
     SET_MACHINE_COMPAT(mc, VIRT_COMPAT_2_12);
+    vmc->no_highmem_ecam = true;
+    mc->max_cpus = 255;
 }
-DEFINE_VIRT_MACHINE_AS_LATEST(2, 12)
+DEFINE_VIRT_MACHINE(2, 12)
 
 #define VIRT_COMPAT_2_11 \
     HW_COMPAT_2_11
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 2c18a59..8c74d4c 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -98,6 +98,7 @@ typedef struct {
     bool no_pmu;
     bool claim_edge_triggered_timers;
     bool smbios_old_sys_ver;
+    bool no_highmem_ecam;
 } VirtMachineClass;
 
 typedef struct {
-- 
2.5.5