[PATCH AUTOSEL for 4.9 291/293] irqchip/gic-v3: Ignore disabled ITS nodes

[Sasha Levin]

From: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>

[ Upstream commit 95a2562590c2f64a0398183f978d5cf3db6d0284 ]

On some platforms there's an ITS available but it's not enabled
because reading or writing the registers is denied by the
firmware. In fact, reading or writing them will cause the system
to reset. We could remove the node from DT in such a case, but
it's better to skip nodes that are marked as "disabled" in DT so
that we can describe the hardware that exists and use the status
property to indicate how the firmware has configured things.

Cc: Stuart Yoder <stuyoder@xxxxxxxxx>
Cc: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
 drivers/irqchip/irq-gic-v3-its-pci-msi.c               | 2 ++
 drivers/irqchip/irq-gic-v3-its-platform-msi.c          | 2 ++
 drivers/irqchip/irq-gic-v3-its.c                       | 2 ++
 drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c | 2 ++
 4 files changed, 8 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
index 77931214d954..6b5f50e1fc72 100644
--- a/drivers/irqchip/irq-gic-v3-its-pci-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c
@@ -132,6 +132,8 @@ static int __init its_pci_of_msi_init(void)
 
 	for (np = of_find_matching_node(NULL, its_device_id); np;
 	     np = of_find_matching_node(np, its_device_id)) {
+		if (!of_device_is_available(np))
+			continue;
 		if (!of_property_read_bool(np, "msi-controller"))
 			continue;
 
diff --git a/drivers/irqchip/irq-gic-v3-its-platform-msi.c b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
index 470b4aa7d62c..e4768fcdc672 100644
--- a/drivers/irqchip/irq-gic-v3-its-platform-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
@@ -80,6 +80,8 @@ static int __init its_pmsi_init(void)
 
 	for (np = of_find_matching_node(NULL, its_device_id); np;
 	     np = of_find_matching_node(np, its_device_id)) {
+		if (!of_device_is_available(np))
+			continue;
 		if (!of_property_read_bool(np, "msi-controller"))
 			continue;
 
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index ac15e5d5d9b2..558c7589c329 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1807,6 +1807,8 @@ static int __init its_of_probe(struct device_node *node)
 
 	for (np = of_find_matching_node(node, its_device_id); np;
 	     np = of_find_matching_node(np, its_device_id)) {
+		if (!of_device_is_available(np))
+			continue;
 		if (!of_property_read_bool(np, "msi-controller")) {
 			pr_warn("%s: no msi-controller property, ITS ignored\n",
 				np->full_name);
diff --git a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
index eaeb3c51e14b..cb95c3e940f1 100644
--- a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
+++ b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
@@ -75,6 +75,8 @@ int __init its_fsl_mc_msi_init(void)
 
 	for (np = of_find_matching_node(NULL, its_device_id); np;
 	     np = of_find_matching_node(np, its_device_id)) {
+		if (!of_device_is_available(np))
+			continue;
 		if (!of_property_read_bool(np, "msi-controller"))
 			continue;
 
-- 
2.15.1