ppc/pnv: Introduce user creatable pnv-phb4 devices

This patch introduces pnv-phb4 user creatable devices that are created
in a similar manner as pnv-phb3 devices, allowing the user to interact
with the PHBs directly instead of creating PCI Express Controllers that
will create a certain amount of PHBs per controller index.

We accomplish this by doing the following:

- add a pnv_phb4_get_stack() helper to retrieve which stack an user
created phb4 would occupy;

- when dealing with an user created pnv-phb4 (detected by checking if
phb->stack is NULL at the start of phb4_realize()), retrieve its stack
and initialize its properties as done in stk_realize();

- use 'defaults_enabled()' in stk_realize() to avoid creating and
initializing a 'stack->phb' qdev that might be overwritten by an user
created pnv-phb4 device. This process is wrapped into a new helper
called pnv_pec_stk_default_phb_realize().

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220111131027.599784-5-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

1 files changed, 15 insertions, 2 deletions

diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
index d4c52a5d28..7fe7f1f007 100644
--- a/hw/pci-host/pnv_phb4_pec.c
+++ b/hw/pci-host/pnv_phb4_pec.c
@@ -19,6 +19,7 @@
 #include "hw/pci/pci_bus.h"
 #include "hw/ppc/pnv.h"
 #include "hw/qdev-properties.h"
+#include "sysemu/sysemu.h"
 
 #include <libfdt.h>
 
@@ -275,9 +276,9 @@ static const TypeInfo pnv_pec_type_info = {
     }
 };
 
-static void pnv_pec_stk_realize(DeviceState *dev, Error **errp)
+static void pnv_pec_stk_default_phb_realize(PnvPhb4PecStack *stack,
+                                            Error **errp)
 {
-    PnvPhb4PecStack *stack = PNV_PHB4_PEC_STACK(dev);
     PnvPhb4PecState *pec = stack->pec;
     PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(pec);
     int phb_id = pnv_phb4_pec_get_phb_id(pec, stack->stack_no);
@@ -292,11 +293,23 @@ static void pnv_pec_stk_realize(DeviceState *dev, Error **errp)
                             &error_fatal);
     object_property_set_link(OBJECT(stack->phb), "stack", OBJECT(stack),
                              &error_abort);
+
     if (!sysbus_realize(SYS_BUS_DEVICE(stack->phb), errp)) {
         return;
     }
 }
 
+static void pnv_pec_stk_realize(DeviceState *dev, Error **errp)
+{
+    PnvPhb4PecStack *stack = PNV_PHB4_PEC_STACK(dev);
+
+    if (!defaults_enabled()) {
+        return;
+    }
+
+    pnv_pec_stk_default_phb_realize(stack, errp);
+}
+
 static Property pnv_pec_stk_properties[] = {
         DEFINE_PROP_UINT32("stack-no", PnvPhb4PecStack, stack_no, 0),
         DEFINE_PROP_LINK("pec", PnvPhb4PecStack, pec, TYPE_PNV_PHB4_PEC,