[PATCH] irqchip/gic-v3: Ignore disabled ITS nodes

[Stephen Boyd <sboyd@codeaurora.org>]

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: Marc Zyngier <marc.zyngier@arm.com>
Cc: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
 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 ++
 3 files changed, 6 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 833a90fe33ae..8881a053c173 100644
--- a/drivers/irqchip/irq-gic-v3-its-platform-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
@@ -154,6 +154,8 @@ static void __init its_pmsi_of_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 284738add89b..a84ee6ce244d 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1815,6 +1815,8 @@ 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);
-- 
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