[PATCH AUTOSEL for 4.9 17/24] irqchip/gic: Make quirks matching conditional on init return value

[alexander . levin]

From: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

[ Upstream commit 9d111d49106b61f5a652d5418e85d8741b1a0427 ]

As it turns out, the IIDR is not sufficient to distinguish between GICv3
implementations when it comes to enabling quirks. So update the prototype
of the init() hook to return a bool, and interpret a 'false' return value
as no match, in which case the 'enabling workaround' log message should
not be printed.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 drivers/irqchip/irq-gic-common.c |  5 +++--
 drivers/irqchip/irq-gic-common.h |  2 +-
 drivers/irqchip/irq-gic-v3-its.c | 12 +++++++++---
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c
index 9ae71804b5dd..30017df5b54c 100644
--- a/drivers/irqchip/irq-gic-common.c
+++ b/drivers/irqchip/irq-gic-common.c
@@ -40,8 +40,9 @@ void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
 	for (; quirks->desc; quirks++) {
 		if (quirks->iidr != (quirks->mask & iidr))
 			continue;
-		quirks->init(data);
-		pr_info("GIC: enabling workaround for %s\n", quirks->desc);
+		if (quirks->init(data))
+			pr_info("GIC: enabling workaround for %s\n",
+				quirks->desc);
 	}
 }
 
diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
index 205e5fddf6da..3919cd7c5285 100644
--- a/drivers/irqchip/irq-gic-common.h
+++ b/drivers/irqchip/irq-gic-common.h
@@ -23,7 +23,7 @@
 
 struct gic_quirk {
 	const char *desc;
-	void (*init)(void *data);
+	bool (*init)(void *data);
 	u32 iidr;
 	u32 mask;
 };
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index acb9d250a905..41996ed1b003 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1584,26 +1584,32 @@ static int its_force_quiescent(void __iomem *base)
 	}
 }
 
-static void __maybe_unused its_enable_quirk_cavium_22375(void *data)
+static bool __maybe_unused its_enable_quirk_cavium_22375(void *data)
 {
 	struct its_node *its = data;
 
 	its->flags |= ITS_FLAGS_WORKAROUND_CAVIUM_22375;
+
+	return true;
 }
 
-static void __maybe_unused its_enable_quirk_cavium_23144(void *data)
+static bool __maybe_unused its_enable_quirk_cavium_23144(void *data)
 {
 	struct its_node *its = data;
 
 	its->flags |= ITS_FLAGS_WORKAROUND_CAVIUM_23144;
+
+	return true;
 }
 
-static void __maybe_unused its_enable_quirk_qdf2400_e0065(void *data)
+static bool __maybe_unused its_enable_quirk_qdf2400_e0065(void *data)
 {
 	struct its_node *its = data;
 
 	/* On QDF2400, the size of the ITE is 16Bytes */
 	its->ite_size = 16;
+
+	return true;
 }
 
 static const struct gic_quirk its_quirks[] = {
-- 
2.11.0