1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gic-realview.c b/drivers/irqchip/irq-gic-realview.c
new file mode 100644
index 000000000..38fab02ff
--- /dev/null
+++ b/drivers/irqchip/irq-gic-realview.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Special GIC quirks for the ARM RealView
+ * Copyright (C) 2015 Linus Walleij
+ */
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/bitops.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/arm-gic.h>
+
+#define REALVIEW_SYS_LOCK_OFFSET	0x20
+#define REALVIEW_SYS_PLD_CTRL1		0x74
+#define REALVIEW_EB_REVB_SYS_PLD_CTRL1	0xD8
+#define VERSATILE_LOCK_VAL		0xA05F
+#define PLD_INTMODE_MASK		BIT(22)|BIT(23)|BIT(24)
+#define PLD_INTMODE_LEGACY		0x0
+#define PLD_INTMODE_NEW_DCC		BIT(22)
+#define PLD_INTMODE_NEW_NO_DCC		BIT(23)
+#define PLD_INTMODE_FIQ_ENABLE		BIT(24)
+
+/* For some reason RealView EB Rev B moved this register */
+static const struct of_device_id syscon_pldset_of_match[] = {
+	{
+		.compatible = "arm,realview-eb11mp-revb-syscon",
+		.data = (void *)REALVIEW_EB_REVB_SYS_PLD_CTRL1,
+	},
+	{
+		.compatible = "arm,realview-eb11mp-revc-syscon",
+		.data = (void *)REALVIEW_SYS_PLD_CTRL1,
+	},
+	{
+		.compatible = "arm,realview-eb-syscon",
+		.data = (void *)REALVIEW_SYS_PLD_CTRL1,
+	},
+	{
+		.compatible = "arm,realview-pb11mp-syscon",
+		.data = (void *)REALVIEW_SYS_PLD_CTRL1,
+	},
+	{},
+};
+
+static int __init
+realview_gic_of_init(struct device_node *node, struct device_node *parent)
+{
+	struct regmap *map;
+	struct device_node *np;
+	const struct of_device_id *gic_id;
+	u32 pld1_ctrl;
+
+	np = of_find_matching_node_and_match(NULL, syscon_pldset_of_match,
+					     &gic_id);
+	if (!np)
+		return -ENODEV;
+	pld1_ctrl = (u32)gic_id->data;
+
+	/* The PB11MPCore GIC needs to be configured in the syscon */
+	map = syscon_node_to_regmap(np);
+	of_node_put(np);
+	if (!IS_ERR(map)) {
+		/* new irq mode with no DCC */
+		regmap_write(map, REALVIEW_SYS_LOCK_OFFSET,
+			     VERSATILE_LOCK_VAL);
+		regmap_update_bits(map, pld1_ctrl,
+				   PLD_INTMODE_NEW_NO_DCC,
+				   PLD_INTMODE_MASK);
+		regmap_write(map, REALVIEW_SYS_LOCK_OFFSET, 0x0000);
+		pr_info("RealView GIC: set up interrupt controller to NEW mode, no DCC\n");
+	} else {
+		pr_err("RealView GIC setup: could not find syscon\n");
+		return -ENODEV;
+	}
+	return gic_of_init(node, parent);
+}
+IRQCHIP_DECLARE(armtc11mp_gic, "arm,tc11mp-gic", realview_gic_of_init);
+IRQCHIP_DECLARE(armeb11mp_gic, "arm,eb11mp-gic", realview_gic_of_init);