hw/pci-host/aspeed: Add AST2600 PCIe Root Device support

Introduce a PCIe Root Device for AST2600 platform.

The AST2600 root complex exposes a PCIe root device at bus 80, devfn 0.
This root device is implemented as a child of the PCIe RC and modeled
as a host bridge PCI function (class_id = PCI_CLASS_BRIDGE_HOST).

Key changes:
- Add a new device type "aspeed.pcie-root-device".
- Instantiate the root device as part of AspeedPCIERcState.
- Initialize it during RC realize() and attach it to the root bus.
- Mark the root device as non-user-creatable.
- Add RC boolean property "has-rd" to control whether the Root Device is
  created (platforms can enable/disable it as needed).

Note: Only AST2600 implements this PCIe root device. AST2700 does not
provide one.

Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250919093017.338309-5-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/include/hw/pci-host/aspeed_pcie.h b/include/hw/pci-host/aspeed_pcie.h
index 850d579189..fe30ac02ae 100644
--- a/include/hw/pci-host/aspeed_pcie.h
+++ b/include/hw/pci-host/aspeed_pcie.h
@@ -40,6 +40,13 @@ typedef struct AspeedPCIERegMap {
     AspeedPCIERcRegs rc;
 } AspeedPCIERegMap;
 
+#define TYPE_ASPEED_PCIE_ROOT_DEVICE "aspeed.pcie-root-device"
+OBJECT_DECLARE_SIMPLE_TYPE(AspeedPCIERootDeviceState, ASPEED_PCIE_ROOT_DEVICE);
+
+struct AspeedPCIERootDeviceState {
+    PCIBridge parent_obj;
+};
+
 #define TYPE_ASPEED_PCIE_RC "aspeed.pcie-rc"
 OBJECT_DECLARE_SIMPLE_TYPE(AspeedPCIERcState, ASPEED_PCIE_RC);
 
@@ -53,7 +60,10 @@ struct AspeedPCIERcState {
 
     uint32_t bus_nr;
     char name[16];
+    bool has_rd;
     qemu_irq irq;
+
+    AspeedPCIERootDeviceState root_device;
 };
 
 /* Bridge between AHB bus and PCIe RC. */
@@ -79,6 +89,7 @@ struct AspeedPCIECfgClass {
 
     uint64_t rc_bus_nr;
     uint64_t nr_regs;
+    bool rc_has_rd;
 };
 
 #define TYPE_ASPEED_PCIE_PHY "aspeed.pcie-phy"