perf/x86/intel/uncore: Remove hard-coded implementation for Node ID mapping location

The method to build PCI bus to socket mapping is similar among
platforms. However, the PCI location which stores Node ID mapping could
vary between different platforms. For example, the Node ID mapping address
on Skylake server is different from the previous platform. Also, to
build the mapping for the PCI bus without UBOX, it has to start from
bus 0 on Skylake server.

This patch removes the current hardcoded implementation and adds
three parameters for snbep_pci2phy_map_init(). This way the Node ID mapping
address and bus searching direction can be configured according to
different platforms.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nilay Vaish <nilayvaish@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1471378190-17276-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/events/intel/uncore_snbep.c

@@ -1,6 +1,10 @@
 /* SandyBridge-EP/IvyTown uncore support */
 #include "uncore.h"
 
+/* SNB-EP pci bus to socket mapping */
+#define SNBEP_CPUNODEID			0x40
+#define SNBEP_GIDNIDMAP			0x54
+
 /* SNB-EP Box level control */
 #define SNBEP_PMON_BOX_CTL_RST_CTRL	(1 << 0)
 #define SNBEP_PMON_BOX_CTL_RST_CTRS	(1 << 1)
@@ -1153,7 +1157,7 @@ static struct pci_driver snbep_uncore_pci_driver = {
 /*
  * build pci bus to socket mapping
  */
-static int snbep_pci2phy_map_init(int devid)
+static int snbep_pci2phy_map_init(int devid, int nodeid_loc, int idmap_loc, bool reverse)
 {
 	struct pci_dev *ubox_dev = NULL;
 	int i, bus, nodeid, segment;
@@ -1168,12 +1172,12 @@ static int snbep_pci2phy_map_init(int devid)
 			break;
 		bus = ubox_dev->bus->number;
 		/* get the Node ID of the local register */
-		err = pci_read_config_dword(ubox_dev, 0x40, &config);
+		err = pci_read_config_dword(ubox_dev, nodeid_loc, &config);
 		if (err)
 			break;
 		nodeid = config;
 		/* get the Node ID mapping */
-		err = pci_read_config_dword(ubox_dev, 0x54, &config);
+		err = pci_read_config_dword(ubox_dev, idmap_loc, &config);
 		if (err)
 			break;
 
@@ -1207,11 +1211,20 @@ static int snbep_pci2phy_map_init(int devid)
 		raw_spin_lock(&pci2phy_map_lock);
 		list_for_each_entry(map, &pci2phy_map_head, list) {
 			i = -1;
-			for (bus = 255; bus >= 0; bus--) {
-				if (map->pbus_to_physid[bus] >= 0)
-					i = map->pbus_to_physid[bus];
-				else
-					map->pbus_to_physid[bus] = i;
+			if (reverse) {
+				for (bus = 255; bus >= 0; bus--) {
+					if (map->pbus_to_physid[bus] >= 0)
+						i = map->pbus_to_physid[bus];
+					else
+						map->pbus_to_physid[bus] = i;
+				}
+			} else {
+				for (bus = 0; bus <= 255; bus++) {
+					if (map->pbus_to_physid[bus] >= 0)
+						i = map->pbus_to_physid[bus];
+					else
+						map->pbus_to_physid[bus] = i;
+				}
 			}
 		}
 		raw_spin_unlock(&pci2phy_map_lock);
@@ -1224,7 +1237,7 @@ static int snbep_pci2phy_map_init(int devid)
 
 int snbep_uncore_pci_init(void)
 {
-	int ret = snbep_pci2phy_map_init(0x3ce0);
+	int ret = snbep_pci2phy_map_init(0x3ce0, SNBEP_CPUNODEID, SNBEP_GIDNIDMAP, true);
 	if (ret)
 		return ret;
 	uncore_pci_uncores = snbep_pci_uncores;
@@ -1788,7 +1801,7 @@ static struct pci_driver ivbep_uncore_pci_driver = {
 
 int ivbep_uncore_pci_init(void)
 {
-	int ret = snbep_pci2phy_map_init(0x0e1e);
+	int ret = snbep_pci2phy_map_init(0x0e1e, SNBEP_CPUNODEID, SNBEP_GIDNIDMAP, true);
 	if (ret)
 		return ret;
 	uncore_pci_uncores = ivbep_pci_uncores;
@@ -2897,7 +2910,7 @@ static struct pci_driver hswep_uncore_pci_driver = {
 
 int hswep_uncore_pci_init(void)
 {
-	int ret = snbep_pci2phy_map_init(0x2f1e);
+	int ret = snbep_pci2phy_map_init(0x2f1e, SNBEP_CPUNODEID, SNBEP_GIDNIDMAP, true);
 	if (ret)
 		return ret;
 	uncore_pci_uncores = hswep_pci_uncores;
@@ -3186,7 +3199,7 @@ static struct pci_driver bdx_uncore_pci_driver = {
 
 int bdx_uncore_pci_init(void)
 {
-	int ret = snbep_pci2phy_map_init(0x6f1e);
+	int ret = snbep_pci2phy_map_init(0x6f1e, SNBEP_CPUNODEID, SNBEP_GIDNIDMAP, true);
 
 	if (ret)
 		return ret;