This interrupt controller is present on bcm63xx SoCs in order to generate
interrupts based on GPIO status changes.

Signed-off-by: Álvaro Fernández Rojas <nolt...@gmail.com>
Signed-off-by: Jonas Gorski <jonas.gor...@gmail.com>
---
 v2: no changes.

 drivers/irqchip/Kconfig           |   4 +
 drivers/irqchip/Makefile          |   1 +
 drivers/irqchip/irq-bcm6345-ext.c | 271 ++++++++++++++++++++++++++++++
 3 files changed, 276 insertions(+)
 create mode 100644 drivers/irqchip/irq-bcm6345-ext.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index e74fa206240a..eaa101939a34 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -113,6 +113,10 @@ config I8259
        bool
        select IRQ_DOMAIN
 
+config BCM6345_EXT_IRQ
+       bool "BCM6345 External IRQ Controller"
+       select IRQ_DOMAIN
+
 config BCM6345_L1_IRQ
        bool
        select GENERIC_IRQ_CHIP
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c59b95a0532c..3cba65bc0aa5 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_XTENSA_MX)                       += 
irq-xtensa-mx.o
 obj-$(CONFIG_XILINX_INTC)              += irq-xilinx-intc.o
 obj-$(CONFIG_IRQ_CROSSBAR)             += irq-crossbar.o
 obj-$(CONFIG_SOC_VF610)                        += irq-vf610-mscm-ir.o
+obj-$(CONFIG_BCM6345_EXT_IRQ)          += irq-bcm6345-ext.o
 obj-$(CONFIG_BCM6345_L1_IRQ)           += irq-bcm6345-l1.o
 obj-$(CONFIG_BCM7038_L1_IRQ)           += irq-bcm7038-l1.o
 obj-$(CONFIG_BCM7120_L2_IRQ)           += irq-bcm7120-l2.o
diff --git a/drivers/irqchip/irq-bcm6345-ext.c 
b/drivers/irqchip/irq-bcm6345-ext.c
new file mode 100644
index 000000000000..5721ac8de295
--- /dev/null
+++ b/drivers/irqchip/irq-bcm6345-ext.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Broadcom BCM6345 style external interrupt controller driver
+ *
+ * Copyright (C) 2021 Álvaro Fernández Rojas <nolt...@gmail.com>
+ * Copyright (C) 2014 Jonas Gorski <jonas.gor...@gmail.com>
+ */
+
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#define MAX_IRQS               4
+
+#define EXTIRQ_CFG_SENSE       0
+#define EXTIRQ_CFG_STAT                1
+#define EXTIRQ_CFG_CLEAR       2
+#define EXTIRQ_CFG_MASK                3
+#define EXTIRQ_CFG_BOTHEDGE    4
+#define EXTIRQ_CFG_LEVELSENSE  5
+
+struct intc_data {
+       struct irq_chip chip;
+       struct irq_domain *domain;
+       raw_spinlock_t lock;
+
+       int parent_irq[MAX_IRQS];
+       void __iomem *reg;
+       int shift;
+       unsigned int toggle_clear_on_ack:1;
+};
+
+static void bcm6345_ext_intc_irq_handle(struct irq_desc *desc)
+{
+       struct intc_data *data = irq_desc_get_handler_data(desc);
+       struct irq_chip *chip = irq_desc_get_chip(desc);
+       unsigned int irq = irq_desc_get_irq(desc);
+       unsigned int idx;
+
+       chained_irq_enter(chip, desc);
+
+       for (idx = 0; idx < MAX_IRQS; idx++) {
+               if (data->parent_irq[idx] != irq)
+                       continue;
+
+               generic_handle_irq(irq_find_mapping(data->domain, idx));
+       }
+
+       chained_irq_exit(chip, desc);
+}
+
+static void bcm6345_ext_intc_irq_ack(struct irq_data *data)
+{
+       struct intc_data *priv = data->domain->host_data;
+       irq_hw_number_t hwirq = irqd_to_hwirq(data);
+       u32 reg;
+
+       raw_spin_lock(&priv->lock);
+       reg = __raw_readl(priv->reg);
+       __raw_writel(reg | (1 << (hwirq + EXTIRQ_CFG_CLEAR * priv->shift)),
+                    priv->reg);
+       if (priv->toggle_clear_on_ack)
+               __raw_writel(reg, priv->reg);
+       raw_spin_unlock(&priv->lock);
+}
+
+static void bcm6345_ext_intc_irq_mask(struct irq_data *data)
+{
+       struct intc_data *priv = data->domain->host_data;
+       irq_hw_number_t hwirq = irqd_to_hwirq(data);
+       u32 reg;
+
+       raw_spin_lock(&priv->lock);
+       reg = __raw_readl(priv->reg);
+       reg &= ~(1 << (hwirq + EXTIRQ_CFG_MASK * priv->shift));
+       __raw_writel(reg, priv->reg);
+       raw_spin_unlock(&priv->lock);
+}
+
+static void bcm6345_ext_intc_irq_unmask(struct irq_data *data)
+{
+       struct intc_data *priv = data->domain->host_data;
+       irq_hw_number_t hwirq = irqd_to_hwirq(data);
+       u32 reg;
+
+       raw_spin_lock(&priv->lock);
+       reg = __raw_readl(priv->reg);
+       reg |= 1 << (hwirq + EXTIRQ_CFG_MASK * priv->shift);
+       __raw_writel(reg, priv->reg);
+       raw_spin_unlock(&priv->lock);
+}
+
+static int bcm6345_ext_intc_set_type(struct irq_data *data,
+                                    unsigned int flow_type)
+{
+       struct intc_data *priv = data->domain->host_data;
+       irq_hw_number_t hwirq = irqd_to_hwirq(data);
+       bool levelsense = 0, sense = 0, bothedge = 0;
+       u32 reg;
+
+       flow_type &= IRQ_TYPE_SENSE_MASK;
+
+       if (flow_type == IRQ_TYPE_NONE)
+               flow_type = IRQ_TYPE_LEVEL_LOW;
+
+       switch (flow_type) {
+       case IRQ_TYPE_EDGE_BOTH:
+               bothedge = 1;
+               break;
+
+       case IRQ_TYPE_EDGE_RISING:
+               sense = 1;
+               break;
+
+       case IRQ_TYPE_EDGE_FALLING:
+               break;
+
+       case IRQ_TYPE_LEVEL_HIGH:
+               levelsense = 1;
+               sense = 1;
+               break;
+
+       case IRQ_TYPE_LEVEL_LOW:
+               levelsense = 1;
+               break;
+
+       default:
+               pr_err("bogus flow type combination given!\n");
+               return -EINVAL;
+       }
+
+       raw_spin_lock(&priv->lock);
+       reg = __raw_readl(priv->reg);
+
+       if (levelsense)
+               reg |= 1 << (hwirq + EXTIRQ_CFG_LEVELSENSE * priv->shift);
+       else
+               reg &= ~(1 << (hwirq + EXTIRQ_CFG_LEVELSENSE * priv->shift));
+       if (sense)
+               reg |= 1 << (hwirq + EXTIRQ_CFG_SENSE * priv->shift);
+       else
+               reg &= ~(1 << (hwirq + EXTIRQ_CFG_SENSE * priv->shift));
+       if (bothedge)
+               reg |= 1 << (hwirq + EXTIRQ_CFG_BOTHEDGE * priv->shift);
+       else
+               reg &= ~(1 << (hwirq + EXTIRQ_CFG_BOTHEDGE * priv->shift));
+
+       __raw_writel(reg, priv->reg);
+       raw_spin_unlock(&priv->lock);
+
+       irqd_set_trigger_type(data, flow_type);
+       if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
+               irq_set_handler_locked(data, handle_level_irq);
+       else
+               irq_set_handler_locked(data, handle_edge_irq);
+
+       return 0;
+}
+
+static int bcm6345_ext_intc_map(struct irq_domain *d, unsigned int irq,
+                               irq_hw_number_t hw)
+{
+       struct intc_data *priv = d->host_data;
+
+       irq_set_chip_and_handler(irq, &priv->chip, handle_level_irq);
+
+       return 0;
+}
+
+static const struct irq_domain_ops bcm6345_ext_domain_ops = {
+       .xlate = irq_domain_xlate_twocell,
+       .map = bcm6345_ext_intc_map,
+};
+
+static int __init bcm6345_ext_intc_init(struct device_node *node,
+                                       int num_irqs, int *irqs,
+                                       void __iomem *reg, int shift,
+                                       bool toggle_clear_on_ack)
+{
+       struct intc_data *data;
+       unsigned int i;
+
+       data = kzalloc(sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       raw_spin_lock_init(&data->lock);
+
+       for (i = 0; i < num_irqs; i++) {
+               data->parent_irq[i] = irqs[i];
+
+               irq_set_handler_data(irqs[i], data);
+               irq_set_chained_handler(irqs[i], bcm6345_ext_intc_irq_handle);
+       }
+
+       data->reg = reg;
+       data->shift = shift;
+       data->toggle_clear_on_ack = toggle_clear_on_ack;
+
+       data->chip.name = "bcm6345-ext-intc";
+       data->chip.irq_ack = bcm6345_ext_intc_irq_ack;
+       data->chip.irq_mask = bcm6345_ext_intc_irq_mask;
+       data->chip.irq_unmask = bcm6345_ext_intc_irq_unmask;
+       data->chip.irq_set_type = bcm6345_ext_intc_set_type;
+
+       data->domain = irq_domain_add_simple(node, num_irqs, 0,
+                                            &bcm6345_ext_domain_ops, data);
+       if (!data->domain) {
+               kfree(data);
+               return -ENOMEM;
+       }
+
+       return 0;
+}
+
+static int __init bcm6345_ext_intc_of_init(struct device_node *node,
+                                          struct device_node *parent)
+{
+       int num_irqs, ret = -EINVAL;
+       unsigned i;
+       void __iomem *base;
+       int irqs[MAX_IRQS] = { 0 };
+       u32 shift;
+       bool toggle_clear_on_ack = false;
+
+       num_irqs = of_irq_count(node);
+
+       if (!num_irqs || num_irqs > MAX_IRQS)
+               return -EINVAL;
+
+       if (of_property_read_u32(node, "brcm,field-width", &shift))
+               shift = 4;
+
+       /* On BCM6318 setting CLEAR seems to continuously mask interrupts */
+       if (of_device_is_compatible(node, "brcm,bcm6318-ext-intc"))
+               toggle_clear_on_ack = true;
+
+       for (i = 0; i < num_irqs; i++) {
+               irqs[i] = irq_of_parse_and_map(node, i);
+               if (!irqs[i])
+                       return -ENOMEM;
+       }
+
+       base = of_iomap(node, 0);
+       if (!base)
+               return -ENXIO;
+
+       ret = bcm6345_ext_intc_init(node, num_irqs, irqs, base, shift,
+                                   toggle_clear_on_ack);
+       if (!ret)
+               return 0;
+
+       iounmap(base);
+
+       for (i = 0; i < num_irqs; i++)
+               irq_dispose_mapping(irqs[i]);
+
+       return ret;
+}
+
+IRQCHIP_DECLARE(bcm6318_ext_intc, "brcm,bcm6318-ext-intc",
+               bcm6345_ext_intc_of_init);
+IRQCHIP_DECLARE(bcm6345_ext_intc, "brcm,bcm6345-ext-intc",
+               bcm6345_ext_intc_of_init);
-- 
2.20.1

Reply via email to