3 files changed, 209 insertions, 0 deletions

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index d770f7406631..bbb746e35500 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -30,6 +30,12 @@ config ARM_VIC_NR
           The maximum number of VICs available in the system, for
           power management.
 
+config BRCMSTB_L2_IRQ
+        bool
+        depends on ARM
+        select GENERIC_IRQ_CHIP
+        select IRQ_DOMAIN
+
 config DW_APB_ICTL
         bool
         select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index f180f8d5fb7b..62a13e5ef98f 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -29,3 +29,4 @@ obj-$(CONFIG_TB10X_IRQC)		+= irq-tb10x.o
 obj-$(CONFIG_XTENSA)                    += irq-xtensa-pic.o
 obj-$(CONFIG_XTENSA_MX)                 += irq-xtensa-mx.o
 obj-$(CONFIG_IRQ_CROSSBAR)              += irq-crossbar.o
+obj-$(CONFIG_BRCMSTB_L2_IRQ)            += irq-brcmstb-l2.o
diff --git a/drivers/irqchip/irq-brcmstb-l2.c b/drivers/irqchip/irq-brcmstb-l2.c
new file mode 100644
index 000000000000..8ee2a36d5840
--- /dev/null
+++ b/drivers/irqchip/irq-brcmstb-l2.c
@@ -0,0 +1,202 @@
+/*
+ * Generic Broadcom Set Top Box Level 2 Interrupt controller driver
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt)     KBUILD_MODNAME  ": " fmt
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+
+#include <asm/mach/irq.h>
+
+#include "irqchip.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
+
+/* L2 intc private data structure */
+struct brcmstb_l2_intc_data {
+        int parent_irq;
+        void __iomem *base;
+        struct irq_domain *domain;
+        bool can_wake;
+        u32 saved_mask; /* for suspend/resume */
+};
+
+static void brcmstb_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc)
+{
+        struct brcmstb_l2_intc_data *b = irq_desc_get_handler_data(desc);
+        struct irq_chip *chip = irq_desc_get_chip(desc);
+        u32 status;
+
+        chained_irq_enter(chip, desc);
+
+        status = __raw_readl(b->base + CPU_STATUS) &
+                ~(__raw_readl(b->base + CPU_MASK_STATUS));
+
+        if (status == 0) {
+                do_bad_IRQ(irq, desc);
+                goto out;
+        }
+
+        do {
+                irq = ffs(status) - 1;
+                /* ack at our level */
+                __raw_writel(1 << irq, b->base + CPU_CLEAR);
+                status &= ~(1 << irq);
+                generic_handle_irq(irq_find_mapping(b->domain, irq));
+        } while (status);
+out:
+        chained_irq_exit(chip, desc);
+}
+
+static void brcmstb_l2_intc_suspend(struct irq_data *d)
+{
+        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+        struct brcmstb_l2_intc_data *b = gc->private;
+
+        irq_gc_lock(gc);
+        /* Save the current mask */
+        b->saved_mask = __raw_readl(b->base + CPU_MASK_STATUS);
+
+        if (b->can_wake) {
+                /* Program the wakeup mask */
+                __raw_writel(~gc->wake_active, b->base + CPU_MASK_SET);
+                __raw_writel(gc->wake_active, b->base + CPU_MASK_CLEAR);
+        }
+        irq_gc_unlock(gc);
+}
+
+static void brcmstb_l2_intc_resume(struct irq_data *d)
+{
+        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+        struct brcmstb_l2_intc_data *b = gc->private;
+
+        irq_gc_lock(gc);
+        /* Clear unmasked non-wakeup interrupts */
+        __raw_writel(~b->saved_mask & ~gc->wake_active, b->base + CPU_CLEAR);
+
+        /* Restore the saved mask */
+        __raw_writel(b->saved_mask, b->base + CPU_MASK_SET);
+        __raw_writel(~b->saved_mask, b->base + CPU_MASK_CLEAR);
+        irq_gc_unlock(gc);
+}
+
+int __init brcmstb_l2_intc_of_init(struct device_node *np,
+                                        struct device_node *parent)
+{
+        unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+        struct brcmstb_l2_intc_data *data;
+        struct irq_chip_generic *gc;
+        struct irq_chip_type *ct;
+        int ret;
+
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        data->base = of_iomap(np, 0);
+        if (!data->base) {
+                pr_err("failed to remap intc L2 registers\n");
+                ret = -ENOMEM;
+                goto out_free;
+        }
+
+        /* Disable all interrupts by default */
+        __raw_writel(0xffffffff, data->base + CPU_MASK_SET);
+        __raw_writel(0xffffffff, data->base + CPU_CLEAR);
+
+        data->parent_irq = irq_of_parse_and_map(np, 0);
+        if (data->parent_irq < 0) {
+                pr_err("failed to find parent interrupt\n");
+                ret = data->parent_irq;
+                goto out_unmap;
+        }
+
+        data->domain = irq_domain_add_linear(np, 32,
+                                &irq_generic_chip_ops, NULL);
+        if (!data->domain) {
+                ret = -ENOMEM;
+                goto out_unmap;
+        }
+
+        /* Allocate a single Generic IRQ chip for this node */
+        ret = irq_alloc_domain_generic_chips(data->domain, 32, 1,
+                                np->full_name, handle_level_irq, clr, 0, 0);
+        if (ret) {
+                pr_err("failed to allocate generic irq chip\n");
+                goto out_free_domain;
+        }
+
+        /* Set the IRQ chaining logic */
+        irq_set_handler_data(data->parent_irq, data);
+        irq_set_chained_handler(data->parent_irq, brcmstb_l2_intc_irq_handle);
+
+        gc = irq_get_domain_generic_chip(data->domain, 0);
+        gc->reg_base = data->base;
+        gc->private = data;
+        ct = gc->chip_types;
+
+        ct->chip.irq_ack = irq_gc_ack_set_bit;
+        ct->regs.ack = CPU_CLEAR;
+
+        ct->chip.irq_mask = irq_gc_mask_disable_reg;
+        ct->regs.disable = CPU_MASK_SET;
+
+        ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
+        ct->regs.enable = CPU_MASK_CLEAR;
+
+        ct->chip.irq_suspend = brcmstb_l2_intc_suspend;
+        ct->chip.irq_resume = brcmstb_l2_intc_resume;
+
+        if (of_property_read_bool(np, "brcm,irq-can-wake")) {
+                data->can_wake = true;
+                /* This IRQ chip can wake the system, set all child interrupts
+                 * in wake_enabled mask
+                 */
+                gc->wake_enabled = 0xffffffff;
+                ct->chip.irq_set_wake = irq_gc_set_wake;
+        }
+
+        pr_info("registered L2 intc (mem: 0x%p, parent irq: %d)\n",
+                        data->base, data->parent_irq);
+
+        return 0;
+
+out_free_domain:
+        irq_domain_remove(data->domain);
+out_unmap:
+        iounmap(data->base);
+out_free:
+        kfree(data);
+        return ret;
+}
+IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,l2-intc", brcmstb_l2_intc_of_init);