Re: [PATCH for-7.2 2/2] ppc/pnv: fix QOM parenting of user creatable root ports

[Cédric Le Goater]

On 8/19/22 00:45, Daniel Henrique Barboza wrote:

User creatable root ports are being parented by the 'peripheral' or the
'peripheral-anon' container. This happens because this is the regular
QOM schema for sysbus devices that are added via the command line.

Let's make this QOM hierarchy similar to what we have with default root
ports, i.e. the root port must be parented by the pnv-root-bus. To do
that we change the qom and bus parent of the root port during
root_port_realize(). The realize() is shared by the default root port
code path, so we can remove the code inside pnv_phb_attach_root_port()
that was adding the root port as a child of the bus as well.

While we're at it, change pnv_phb_attach_root_port() to receive a PCIBus
instead of a PCIHostState to make it clear that the function does not
make use of the PHB.

Signed-off-by: Daniel Henrique Barboza <danielhb...@gmail.com>
---
  hw/pci-host/pnv_phb.c | 38 +++++++++++++++++++-------------------
  1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/hw/pci-host/pnv_phb.c b/hw/pci-host/pnv_phb.c
index 4ea33fb6ba..38ec8571b7 100644
--- a/hw/pci-host/pnv_phb.c
+++ b/hw/pci-host/pnv_phb.c
@@ -62,27 +62,11 @@ static bool pnv_parent_fixup(Object *parent, BusState 
*parent_bus,
      return true;
  }

-/*

- * Attach a root port device.
- *
- * 'index' will be used both as a PCIE slot value and to calculate
- * QOM id. 'chip_id' is going to be used as PCIE chassis for the
- * root port.
- */
-static void pnv_phb_attach_root_port(PCIHostState *pci)
+static void pnv_phb_attach_root_port(PCIBus *bus)

Do we still need this pnv_phb_attach_root_port routine ?

  {
      PCIDevice *root = pci_new(PCI_DEVFN(0, 0), TYPE_PNV_PHB_ROOT_PORT);
-    const char *dev_id = DEVICE(root)->id;
-    g_autofree char *default_id = NULL;
-    int index;

- index = object_property_get_int(OBJECT(pci->bus), "phb-id", &error_fatal);

-    default_id = g_strdup_printf("%s[%d]", TYPE_PNV_PHB_ROOT_PORT, index);
-
-    object_property_add_child(OBJECT(pci->bus), dev_id ? dev_id : default_id,
-                              OBJECT(root));
-
-    pci_realize_and_unref(root, pci->bus, &error_fatal);
+    pci_realize_and_unref(root, bus, &error_fatal);
  }

/*

@@ -184,7 +168,7 @@ static void pnv_phb_realize(DeviceState *dev, Error **errp)
          return;
      }

- pnv_phb_attach_root_port(pci);

+    pnv_phb_attach_root_port(pci->bus);
  }

static const char *pnv_phb_root_bus_path(PCIHostState *host_bridge,

@@ -259,6 +243,11 @@ static void pnv_phb_root_port_realize(DeviceState *dev, 
Error **errp)
      Error *local_err = NULL;
      int chip_id, index;

+ /*

+     * 'index' will be used both as a PCIE slot value and to calculate
+     * QOM id. 'chip_id' is going to be used as PCIE chassis for the
+     * root port.
+     */
      chip_id = object_property_get_int(OBJECT(bus), "chip-id", &error_fatal);
      index = object_property_get_int(OBJECT(bus), "phb-id", &error_fatal);

@@ -266,6 +255,17 @@ static void pnv_phb_root_port_realize(DeviceState *dev, Error **errp)

      qdev_prop_set_uint8(dev, "chassis", chip_id);
      qdev_prop_set_uint16(dev, "slot", index);

+ /*

+     * User created root ports are QOM parented to one of
+     * the peripheral containers but it's already at the right
+     * parent bus. Change the QOM parent to be the same as the
+     * parent bus it's already assigned to.
+     */
+    if (!pnv_parent_fixup(OBJECT(bus), BUS(bus), OBJECT(dev),
+                          index, errp)) {
+        return;
+    }
+
      rpc->parent_realize(dev, &local_err);
      if (local_err) {
          error_propagate(errp, local_err);