[PATCH 6/6] irqchip: brcmstb-l2: Add support for the BCM7271 L2 controller

[Doug Berger]

Add the initialization of the generic irq chip for the BCM7271 L2
interrupt controller.  This controller only supports level
interrupts and uses the "brcm,bcm7271-l2-intc" compatibility
string.

Signed-off-by: Doug Berger <opendmb@xxxxxxxxx>
---
 .../bindings/interrupt-controller/brcm,l2-intc.txt |  3 +-
 drivers/irqchip/irq-brcmstb-l2.c                   | 86 ++++++++++++++++------
 2 files changed, 66 insertions(+), 23 deletions(-)

diff --git a/Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt b/Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt
index 448273a30a11..36df06c5c567 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt
@@ -2,7 +2,8 @@ Broadcom Generic Level 2 Interrupt Controller
 
 Required properties:
 
-- compatible: should be "brcm,l2-intc"
+- compatible: should be "brcm,l2-intc" for latched interrupt controllers
+              should be "brcm,bcm7271-l2-intc" for level interrupt controllers
 - reg: specifies the base physical address and size of the registers
 - interrupt-controller: identifies the node as an interrupt controller
 - #interrupt-cells: specifies the number of cells needed to encode an
diff --git a/drivers/irqchip/irq-brcmstb-l2.c b/drivers/irqchip/irq-brcmstb-l2.c
index ce3850530e2b..f77e6c9530dc 100644
--- a/drivers/irqchip/irq-brcmstb-l2.c
+++ b/drivers/irqchip/irq-brcmstb-l2.c
@@ -31,13 +31,34 @@
 #include <linux/irqchip.h>
 #include <linux/irqchip/chained_irq.h>
 
-/* Register offsets in the L2 interrupt controller */
-#define CPU_STATUS	0x00
-#define CPU_SET		0x04
-#define CPU_CLEAR	0x08
-#define CPU_MASK_STATUS	0x0c
-#define CPU_MASK_SET	0x10
-#define CPU_MASK_CLEAR	0x14
+struct brcmstb_intc_init_params {
+	irq_flow_handler_t handler;
+	int cpu_status;
+	int cpu_clear;
+	int cpu_mask_status;
+	int cpu_mask_set;
+	int cpu_mask_clear;
+};
+
+/* Register offsets in the L2 latched interrupt controller */
+static const struct brcmstb_intc_init_params l2_edge_intc_init = {
+	.handler		= handle_edge_irq,
+	.cpu_status		= 0x00,
+	.cpu_clear		= 0x08,
+	.cpu_mask_status	= 0x0c,
+	.cpu_mask_set		= 0x10,
+	.cpu_mask_clear		= 0x14
+};
+
+/* Register offsets in the L2 level interrupt controller */
+static const struct brcmstb_intc_init_params l2_lvl_intc_init = {
+	.handler		= handle_level_irq,
+	.cpu_status		= 0x00,
+	.cpu_clear		= -1, /* Register not present */
+	.cpu_mask_status	= 0x04,
+	.cpu_mask_set		= 0x08,
+	.cpu_mask_clear		= 0x0C
+};
 
 /* L2 intc private data structure */
 struct brcmstb_l2_intc_data {
@@ -102,7 +123,7 @@ static void brcmstb_l2_intc_resume(struct irq_data *d)
 	struct brcmstb_l2_intc_data *b = gc->private;
 
 	irq_gc_lock(gc);
-	if (ct->chip.irq_ack != irq_gc_noop) {
+	if (ct->chip.irq_ack) {
 		/* Clear unmasked non-wakeup interrupts */
 		irq_reg_writel(gc, ~b->saved_mask & ~gc->wake_active,
 				ct->regs.ack);
@@ -115,7 +136,9 @@ static void brcmstb_l2_intc_resume(struct irq_data *d)
 }
 
 static int __init brcmstb_l2_intc_of_init(struct device_node *np,
-					  struct device_node *parent)
+					  struct device_node *parent,
+					  const struct brcmstb_intc_init_params
+					  *init_params)
 {
 	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
 	struct brcmstb_l2_intc_data *data;
@@ -137,12 +160,12 @@ static int __init brcmstb_l2_intc_of_init(struct device_node *np,
 	}
 
 	/* Disable all interrupts by default */
-	writel(0xffffffff, base + CPU_MASK_SET);
+	writel(0xffffffff, base + init_params->cpu_mask_set);
 
 	/* Wakeup interrupts may be retained from S5 (cold boot) */
 	data->can_wake = of_property_read_bool(np, "brcm,irq-can-wake");
-	if (!data->can_wake)
-		writel(0xffffffff, base + CPU_CLEAR);
+	if (!data->can_wake && (init_params->cpu_clear >= 0))
+		writel(0xffffffff, base + init_params->cpu_clear);
 
 	parent_irq = irq_of_parse_and_map(np, 0);
 	if (!parent_irq) {
@@ -167,7 +190,7 @@ static int __init brcmstb_l2_intc_of_init(struct device_node *np,
 
 	/* Allocate a single Generic IRQ chip for this node */
 	ret = irq_alloc_domain_generic_chips(data->domain, 32, 1,
-				np->full_name, handle_edge_irq, clr, 0, flags);
+			np->full_name, init_params->handler, clr, 0, flags);
 	if (ret) {
 		pr_err("failed to allocate generic irq chip\n");
 		goto out_free_domain;
@@ -180,21 +203,26 @@ static int __init brcmstb_l2_intc_of_init(struct device_node *np,
 	data->gc = irq_get_domain_generic_chip(data->domain, 0);
 	data->gc->reg_base = base;
 	data->gc->private = data;
-	data->status_offset = CPU_STATUS;
-	data->mask_offset = CPU_MASK_STATUS;
+	data->status_offset = init_params->cpu_status;
+	data->mask_offset = init_params->cpu_mask_status;
 
 	ct = data->gc->chip_types;
 
-	ct->chip.irq_ack = irq_gc_ack_set_bit;
-	ct->regs.ack = CPU_CLEAR;
+	if (init_params->cpu_clear >= 0) {
+		ct->regs.ack = init_params->cpu_clear;
+		ct->chip.irq_ack = irq_gc_ack_set_bit;
+		ct->chip.irq_mask_ack = irq_gc_mask_disable_and_ack_set;
+	} else {
+		/* No Ack - but still slightly more efficient to define this */
+		ct->chip.irq_mask_ack = irq_gc_mask_disable_reg;
+	}
 
 	ct->chip.irq_mask = irq_gc_mask_disable_reg;
-	ct->chip.irq_mask_ack = irq_gc_mask_disable_and_ack_set;
-	ct->regs.disable = CPU_MASK_SET;
-	ct->regs.mask = CPU_MASK_STATUS;
+	ct->regs.disable = init_params->cpu_mask_set;
+	ct->regs.mask = init_params->cpu_mask_status;
 
 	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
-	ct->regs.enable = CPU_MASK_CLEAR;
+	ct->regs.enable = init_params->cpu_mask_clear;
 
 	ct->chip.irq_suspend = brcmstb_l2_intc_suspend;
 	ct->chip.irq_resume = brcmstb_l2_intc_resume;
@@ -220,4 +248,18 @@ static int __init brcmstb_l2_intc_of_init(struct device_node *np,
 	kfree(data);
 	return ret;
 }
-IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,l2-intc", brcmstb_l2_intc_of_init);
+
+int __init brcmstb_l2_edge_intc_of_init(struct device_node *np,
+	struct device_node *parent)
+{
+	return brcmstb_l2_intc_of_init(np, parent, &l2_edge_intc_init);
+}
+IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,l2-intc", brcmstb_l2_edge_intc_of_init);
+
+int __init brcmstb_l2_lvl_intc_of_init(struct device_node *np,
+	struct device_node *parent)
+{
+	return brcmstb_l2_intc_of_init(np, parent, &l2_lvl_intc_init);
+}
+IRQCHIP_DECLARE(bcm7271_l2_intc, "brcm,bcm7271-l2-intc",
+	brcmstb_l2_lvl_intc_of_init);
-- 
2.13.0