[PATCH v4 3/3] irqchip: brcmstb-l2: Add support for the BCM7271 L2 controller

From: Doug Berger
Date: Mon Sep 18 2017 - 21:00:37 EST


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.

Acked-by: Rob Herring <robh@xxxxxxxxxx>
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 8d54cd7a090d..691d20eb0bec 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 {
@@ -128,7 +149,7 @@ 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);
@@ -141,7 +162,9 @@ 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;
@@ -163,12 +186,12 @@ 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) {
@@ -193,7 +216,7 @@ 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;
@@ -206,21 +229,26 @@ 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 = brcmstb_l2_mask_and_ack;
+ } 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 = brcmstb_l2_mask_and_ack;
- 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;
@@ -247,4 +275,18 @@ 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);
--
2.14.1