From 2ab51ddeca2fc32a7040d8560415be3366fa9ba7 Mon Sep 17 00:00:00 2001
From: Tomasz Nowicki <tn@semihalf.com>
Date: Fri, 10 Jun 2016 15:36:26 -0500
Subject: [PATCH] ARM64: PCI: Add acpi_pci_bus_find_domain_nr()

Extend pci_bus_find_domain_nr() so it can find the domain from either:

  - ACPI, via the new acpi_pci_bus_find_domain_nr() interface, or
  - DT, via of_pci_bus_find_domain_nr()

Note that this is only used for CONFIG_PCI_DOMAINS_GENERIC=y, so it does
not affect x86 or ia64.

[bhelgaas: changelog]
Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 arch/arm64/kernel/pci.c | 7 +++++++
 drivers/pci/pci.c       | 4 +++-
 include/linux/pci.h     | 6 ++++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 3c4e308b40a0..d5d3d26834cf 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -17,6 +17,7 @@
 #include <linux/mm.h>
 #include <linux/of_pci.h>
 #include <linux/of_platform.h>
+#include <linux/pci.h>
 #include <linux/slab.h>
 
 /*
@@ -85,6 +86,12 @@ EXPORT_SYMBOL(pcibus_to_node);
 #endif
 
 #ifdef CONFIG_ACPI
+
+int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
+{
+	return 0;
+}
+
 /* Root bridge scanning */
 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 {
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 97f7cd4a7e86..4834ceeca0d2 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -7,6 +7,7 @@
  *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
  */
 
+#include <linux/acpi.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/init.h>
@@ -4990,7 +4991,8 @@ static int of_pci_bus_find_domain_nr(struct device *parent)
 
 int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
 {
-	return of_pci_bus_find_domain_nr(parent);
+	return acpi_disabled ? of_pci_bus_find_domain_nr(parent) :
+			       acpi_pci_bus_find_domain_nr(bus);
 }
 #endif
 #endif
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 48839e817ef2..0671e9a840cb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1390,6 +1390,12 @@ static inline int pci_domain_nr(struct pci_bus *bus)
 {
 	return bus->domain_nr;
 }
+#ifdef CONFIG_ACPI
+int acpi_pci_bus_find_domain_nr(struct pci_bus *bus);
+#else
+static inline int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
+{ return 0; }
+#endif
 int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent);
 #endif
 
-- 
2.39.5