[PATCH] piix4: don't reserve hw resources when hotplug is off globally

[Ani Sinha]

When acpi hotplug is turned off for both root pci bus as well as for pci
bridges, we should not generate the related amls for DSDT table or initialize
related hw ports or reserve hw resources. This change makes sure all those
operations are turned off in the case acpi pci hotplug is off globally.

Signed-off-by: Ani Sinha <a...@anisinha.ca>
---
 hw/acpi/piix4.c      |  6 ++++--
 hw/i386/acpi-build.c | 10 ++++++++--
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index e6163bb6ce..b70b1f98af 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -596,8 +596,10 @@ static void piix4_acpi_system_hot_add_init(MemoryRegion 
*parent,
                           "acpi-gpe0", GPE_LEN);
     memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe);
 
-    acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, parent,
-                    s->use_acpi_hotplug_bridge);
+    if (s->use_acpi_hotplug_bridge || s->use_acpi_root_pci_hotplug) {
+        acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, parent,
+                        s->use_acpi_hotplug_bridge);
+    }
 
     s->cpu_hotplug_legacy = true;
     object_property_add_bool(OBJECT(s), "cpu-hotplug-legacy",
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index b7bcbbbb2a..5365b3d290 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -95,6 +95,7 @@ typedef struct AcpiPmInfo {
     bool s3_disabled;
     bool s4_disabled;
     bool pcihp_bridge_en;
+    bool pcihp_root_en;
     uint8_t s4_val;
     AcpiFadtData fadt;
     uint16_t cpu_hp_io_base;
@@ -245,6 +246,9 @@ static void acpi_get_pm_info(MachineState *machine, 
AcpiPmInfo *pm)
     pm->pcihp_bridge_en =
         object_property_get_bool(obj, "acpi-pci-hotplug-with-bridge-support",
                                  NULL);
+    pm->pcihp_root_en =
+        object_property_get_bool(obj, "acpi-root-pci-hotplug",
+                                 NULL);
 }
 
 static void acpi_get_misc_info(AcpiMiscInfo *info)
@@ -1504,7 +1508,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         build_hpet_aml(dsdt);
         build_piix4_isa_bridge(dsdt);
         build_isa_devices_aml(dsdt);
-        build_piix4_pci_hotplug(dsdt);
+        if (pm->pcihp_bridge_en || pm->pcihp_root_en) {
+            build_piix4_pci_hotplug(dsdt);
+        }
         build_piix4_pci0_int(dsdt);
     } else {
         sb_scope = aml_scope("_SB");
@@ -1698,7 +1704,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
     crs_range_set_free(&crs_range_set);
 
     /* reserve PCIHP resources */
-    if (pm->pcihp_io_len) {
+    if (pm->pcihp_io_len && (pm->pcihp_bridge_en || pm->pcihp_root_en)) {
         dev = aml_device("PHPR");
         aml_append(dev, aml_name_decl("_HID", aml_string("PNP0A06")));
         aml_append(dev,
-- 
2.17.1