sysbus_add_io() just wraps memory_region_add_subregion() while also
obscuring where the memory is attached. So use
memory_region_add_subregion() directly and attach it to the existing
memory region s->bus->address_space_io which is set as an alias to
get_system_io() by the pc machine.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
 hw/pci-host/i440fx.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/hw/pci-host/i440fx.c b/hw/pci-host/i440fx.c
index 262f82c303..9c6882d3fc 100644
--- a/hw/pci-host/i440fx.c
+++ b/hw/pci-host/i440fx.c
@@ -27,6 +27,7 @@
 #include "qemu/range.h"
 #include "hw/i386/pc.h"
 #include "hw/pci/pci.h"
+#include "hw/pci/pci_bus.h"
 #include "hw/pci/pci_host.h"
 #include "hw/pci-host/i440fx.h"
 #include "hw/qdev-properties.h"
@@ -217,10 +218,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
     PCIHostState *s = PCI_HOST_BRIDGE(dev);
     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 
-    sysbus_add_io(sbd, 0xcf8, &s->conf_mem);
+    memory_region_add_subregion(s->bus->address_space_io, 0xcf8, &s->conf_mem);
     sysbus_init_ioports(sbd, 0xcf8, 4);
 
-    sysbus_add_io(sbd, 0xcfc, &s->data_mem);
+    memory_region_add_subregion(s->bus->address_space_io, 0xcfc, &s->data_mem);
     sysbus_init_ioports(sbd, 0xcfc, 4);
 
     /* register i440fx 0xcf8 port as coalesced pio */
-- 
2.39.1

On 4/2/23 16:10, Bernhard Beschow wrote:
> sysbus_add_io() just wraps memory_region_add_subregion() while also
> obscuring where the memory is attached. So use
> memory_region_add_subregion() directly and attach it to the existing
> memory region s->bus->address_space_io which is set as an alias to
> get_system_io() by the pc machine.
> 
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> ---
>   hw/pci-host/i440fx.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/pci-host/i440fx.c b/hw/pci-host/i440fx.c
> index 262f82c303..9c6882d3fc 100644
> --- a/hw/pci-host/i440fx.c
> +++ b/hw/pci-host/i440fx.c
> @@ -27,6 +27,7 @@
>   #include "qemu/range.h"
>   #include "hw/i386/pc.h"
>   #include "hw/pci/pci.h"
> +#include "hw/pci/pci_bus.h"
>   #include "hw/pci/pci_host.h"
>   #include "hw/pci-host/i440fx.h"
>   #include "hw/qdev-properties.h"
> @@ -217,10 +218,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
>       PCIHostState *s = PCI_HOST_BRIDGE(dev);
>       SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
>   
> -    sysbus_add_io(sbd, 0xcf8, &s->conf_mem);
> +    memory_region_add_subregion(s->bus->address_space_io, 0xcf8, &s->conf_mem);

address_space_io is internal to PCIBus. Better would be adding a helper
like pci_bus_io_region() IMO. Anyhow, removing sysbus_add_io() uses is
good, so:

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>