hw/core/sysbus: Introduce sysbus_mmio_map_name() helper

Some sysbus devices have conditional mmio regions. This
happens for instance with the hw/acpi/ged device. In that case
it becomes difficult to predict which index a specific MMIO
region corresponds to when one needs to mmio map the region.
Introduce a new helper that takes the name of the region instead
of its index. If the region is not found this returns -1.
Otherwise it maps the corresponding index and returns this latter.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20250714080639.2525563-31-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

2 files changed, 12 insertions, 0 deletions

diff --git a/hw/core/sysbus.c b/hw/core/sysbus.c
index e71367adfb..ec69e877a2 100644
--- a/hw/core/sysbus.c
+++ b/hw/core/sysbus.c
@@ -151,6 +151,17 @@ void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr)
     sysbus_mmio_map_common(dev, n, addr, false, 0);
 }
 
+int sysbus_mmio_map_name(SysBusDevice *dev, const char *name, hwaddr addr)
+{
+    for (int i = 0; i < dev->num_mmio; i++) {
+        if (!strcmp(dev->mmio[i].memory->name, name)) {
+            sysbus_mmio_map(dev, i, addr);
+            return i;
+        }
+    }
+    return -1;
+}
+
 void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
                              int priority)
 {
diff --git a/include/hw/sysbus.h b/include/hw/sysbus.h
index 7dc88aaa27..18fde8a7b4 100644
--- a/include/hw/sysbus.h
+++ b/include/hw/sysbus.h
@@ -82,6 +82,7 @@ void sysbus_connect_irq(SysBusDevice *dev, int n, qemu_irq irq);
 bool sysbus_is_irq_connected(SysBusDevice *dev, int n);
 qemu_irq sysbus_get_connected_irq(SysBusDevice *dev, int n);
 void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr);
+int sysbus_mmio_map_name(SysBusDevice *dev, const char*name, hwaddr addr);
 void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
                              int priority);