[PATCH 08/17] pnv_phb4.c: introduce pnv_phb4_set_stack_phb_props()

From: Daniel Henrique Barboza <danielhb413@gmail.com>
To: qemu-devel@nongnu.org
Cc: Daniel Henrique Barboza <danielhb413@gmail.com>,
	qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au
Subject: [PATCH 08/17] pnv_phb4.c: introduce pnv_phb4_set_stack_phb_props()
Date: Tue, 28 Dec 2021 16:37:57 -0300	[thread overview]
Message-ID: <20211228193806.1198496-9-danielhb413@gmail.com> (raw)
In-Reply-To: <20211228193806.1198496-1-danielhb413@gmail.com>

We want to be able to support user creatable pnv-phb4 objects to allow
users to instantiate a powernv9 machine similar to what it is done with
powernv8.

The main difference is that pnv-phb3 devs are attached directly to the
system bus and can be created in the command line. PCI devices such as
root-ports can be explictly connected to them. This allows users to
create the phbs, assign a bus name if desired, then connect devices onto
them.

pnv-phb4 devices on the other hand are created by adding PCI Express
Controllers (PEC) that will create a certain amount of pnv-phb4 buses
depending on the PEC index used. Index 0 will create 1 phb, index 1
creates 2 phbs, index 2 creates 3 phbs. Creating all PECs from the same
chip will create 6 PHBs. This doesn't users to rename the buses, like it
is done with pnv-phb3, because there's no user control over how the
pnv-phb4 are being created - aside from the amount of phbs and in which
chips they'll reside.

This implicit relationship between PEC devices and available buses can
be tolerable for users that knows how the hardware works, but it's
annoying for Libvirt to deal with. Since there's no explicit
relationship, in the command line, between the created buses and the PCI
devices that will connect to them, the domain XML needs to make a lot of
extra assumptions regarding the relationship between regular PCI devices
and the existing PECs.

The first step to allow for user creatable pnv-phb4 devices is to
decouple the pvn-phb logic from the pnv-phb4-pec code. This patch adds a
helper called pnv_phb4_set_stack_phb_props() to remove the code from
pnv_phb4_pec.c that initiates the object properties of pnv-phb4 devices.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
---
 hw/pci-host/pnv_phb4.c         | 27 +++++++++++++++++++++++++++
 hw/pci-host/pnv_phb4_pec.c     | 14 +-------------
 include/hw/pci-host/pnv_phb4.h |  1 +
 3 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index 6bd907f91a..0ea505cc94 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -1164,6 +1164,33 @@ static AddressSpace *pnv_phb4_dma_iommu(PCIBus *bus, void *opaque, int devfn)
     return &ds->dma_as;
 }
 
+/*
+ * Set the object properties of a phb in relation with its stack.
+ *
+ * Note: stack->pec must not be NULL.
+ */
+void pnv_phb4_set_stack_phb_props(PnvPhb4PecStack *stack,
+                                  PnvPHB4 *phb)
+{
+    PnvPhb4PecState *pec = stack->pec;
+    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(pec);
+    char name[64];
+
+    snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-stack-%d-phb",
+             pec->chip_id, pec->index, stack->stack_no);
+    pnv_xscom_region_init(&stack->phb_regs_mr, OBJECT(phb),
+                          &pnv_phb4_xscom_ops, phb, name, 0x40);
+
+    object_property_set_int(OBJECT(phb), "chip-id", pec->chip_id,
+                            &error_fatal);
+    object_property_set_int(OBJECT(phb), "version", pecc->version,
+                            &error_fatal);
+    object_property_set_int(OBJECT(phb), "device-id", pecc->device_id,
+                            &error_fatal);
+    object_property_set_link(OBJECT(phb), "stack", OBJECT(stack),
+                             &error_abort);
+}
+
 static void pnv_phb4_instance_init(Object *obj)
 {
     PnvPHB4 *phb = PNV_PHB4(obj);
diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
index 98e7ff78bd..700ee4b185 100644
--- a/hw/pci-host/pnv_phb4_pec.c
+++ b/hw/pci-host/pnv_phb4_pec.c
@@ -595,19 +595,7 @@ static void pnv_pec_stk_realize(DeviceState *dev, Error **errp)
                           PHB4_PEC_PCI_STK_REGS_COUNT);
 
     /* PHB pass-through */
-    snprintf(name, sizeof(name), "xscom-pec-%d.%d-pci-stack-%d-phb",
-             pec->chip_id, pec->index, stack->stack_no);
-    pnv_xscom_region_init(&stack->phb_regs_mr, OBJECT(&stack->phb),
-                          &pnv_phb4_xscom_ops, &stack->phb, name, 0x40);
-
-    object_property_set_int(OBJECT(&stack->phb), "chip-id", pec->chip_id,
-                            &error_fatal);
-    object_property_set_int(OBJECT(&stack->phb), "version", pecc->version,
-                            &error_fatal);
-    object_property_set_int(OBJECT(&stack->phb), "device-id", pecc->device_id,
-                            &error_fatal);
-    object_property_set_link(OBJECT(&stack->phb), "stack", OBJECT(stack),
-                             &error_abort);
+    pnv_phb4_set_stack_phb_props(stack, &stack->phb);
     if (!sysbus_realize(SYS_BUS_DEVICE(&stack->phb), errp)) {
         return;
     }
diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h
index 629db632d9..d7838513f1 100644
--- a/include/hw/pci-host/pnv_phb4.h
+++ b/include/hw/pci-host/pnv_phb4.h
@@ -133,6 +133,7 @@ struct PnvPHB4 {
 
 void pnv_phb4_pic_print_info(PnvPHB4 *phb, Monitor *mon);
 void pnv_phb4_update_regions(PnvPhb4PecStack *stack);
+void pnv_phb4_set_stack_phb_props(PnvPhb4PecStack *stack, PnvPHB4 *phb);
 extern const MemoryRegionOps pnv_phb4_xscom_ops;
 
 /*
-- 
2.33.1


