microvm: make virtio irq base runtime configurable

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-id: 20200915120909.20838-8-kraxel@redhat.com

hw/i386/microvm.c

@@ -121,10 +121,11 @@ static void microvm_devices_init(MicrovmMachineState *mms)
 
     kvmclock_create();
 
+    mms->virtio_irq_base = 5;
     for (i = 0; i < VIRTIO_NUM_TRANSPORTS; i++) {
         sysbus_create_simple("virtio-mmio",
                              VIRTIO_MMIO_BASE + i * 512,
-                             x86ms->gsi[VIRTIO_IRQ_BASE + i]);
+                             x86ms->gsi[mms->virtio_irq_base + i]);
     }
 
     /* Optional and legacy devices */
@@ -227,7 +228,7 @@ static void microvm_memory_init(MicrovmMachineState *mms)
     x86ms->ioapic_as = &address_space_memory;
 }
 
-static gchar *microvm_get_mmio_cmdline(gchar *name)
+static gchar *microvm_get_mmio_cmdline(gchar *name, uint32_t virtio_irq_base)
 {
     gchar *cmdline;
     gchar *separator;
@@ -247,7 +248,7 @@ static gchar *microvm_get_mmio_cmdline(gchar *name)
     ret = g_snprintf(cmdline, VIRTIO_CMDLINE_MAXLEN,
                      " virtio_mmio.device=512@0x%lx:%ld",
                      VIRTIO_MMIO_BASE + index * 512,
-                     VIRTIO_IRQ_BASE + index);
+                     virtio_irq_base + index);
     if (ret < 0 || ret >= VIRTIO_CMDLINE_MAXLEN) {
         g_free(cmdline);
         return NULL;
@@ -259,6 +260,7 @@ static gchar *microvm_get_mmio_cmdline(gchar *name)
 static void microvm_fix_kernel_cmdline(MachineState *machine)
 {
     X86MachineState *x86ms = X86_MACHINE(machine);
+    MicrovmMachineState *mms = MICROVM_MACHINE(machine);
     BusState *bus;
     BusChild *kid;
     char *cmdline;
@@ -282,7 +284,8 @@ static void microvm_fix_kernel_cmdline(MachineState *machine)
             BusState *mmio_bus = &mmio_virtio_bus->parent_obj;
 
             if (!QTAILQ_EMPTY(&mmio_bus->children)) {
-                gchar *mmio_cmdline = microvm_get_mmio_cmdline(mmio_bus->name);
+                gchar *mmio_cmdline = microvm_get_mmio_cmdline
+                    (mmio_bus->name, mms->virtio_irq_base);
                 if (mmio_cmdline) {
                     char *newcmd = g_strjoin(NULL, cmdline, mmio_cmdline, NULL);
                     g_free(mmio_cmdline);

include/hw/i386/microvm.h

@@ -28,7 +28,6 @@
 
 /* Platform virtio definitions */
 #define VIRTIO_MMIO_BASE      0xfeb00000
-#define VIRTIO_IRQ_BASE       5
 #define VIRTIO_NUM_TRANSPORTS 8
 #define VIRTIO_CMDLINE_MAXLEN 64
 
@@ -59,6 +58,7 @@ struct MicrovmMachineState {
     bool auto_kernel_cmdline;
 
     /* Machine state */
+    uint32_t virtio_irq_base;
     bool kernel_cmdline_fixed;
 };
 typedef struct MicrovmMachineState MicrovmMachineState;