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Diffstat (limited to 'arch/mips/bcm3384/irq.c')
-rw-r--r--arch/mips/bcm3384/irq.c193
1 files changed, 193 insertions, 0 deletions
diff --git a/arch/mips/bcm3384/irq.c b/arch/mips/bcm3384/irq.c
new file mode 100644
index 000000000000..0fb5134fb832
--- /dev/null
+++ b/arch/mips/bcm3384/irq.c
@@ -0,0 +1,193 @@
+/*
+ * 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.
+ *
+ * Partially based on arch/mips/ralink/irq.c
+ *
+ * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2014 Kevin Cernekee <cernekee@gmail.com>
+ */
+
+#include <linux/io.h>
+#include <linux/bitops.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <asm/bmips.h>
+#include <asm/irq_cpu.h>
+#include <asm/mipsregs.h>
+
+/* INTC register offsets */
+#define INTC_REG_ENABLE 0x00
+#define INTC_REG_STATUS 0x04
+
+#define MAX_WORDS 2
+#define IRQS_PER_WORD 32
+
+struct bcm3384_intc {
+ int n_words;
+ void __iomem *reg[MAX_WORDS];
+ u32 enable[MAX_WORDS];
+ spinlock_t lock;
+};
+
+static void bcm3384_intc_irq_unmask(struct irq_data *d)
+{
+ struct bcm3384_intc *priv = d->domain->host_data;
+ unsigned long flags;
+ int idx = d->hwirq / IRQS_PER_WORD;
+ int bit = d->hwirq % IRQS_PER_WORD;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->enable[idx] |= BIT(bit);
+ __raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE);
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void bcm3384_intc_irq_mask(struct irq_data *d)
+{
+ struct bcm3384_intc *priv = d->domain->host_data;
+ unsigned long flags;
+ int idx = d->hwirq / IRQS_PER_WORD;
+ int bit = d->hwirq % IRQS_PER_WORD;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->enable[idx] &= ~BIT(bit);
+ __raw_writel(priv->enable[idx], priv->reg[idx] + INTC_REG_ENABLE);
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static struct irq_chip bcm3384_intc_irq_chip = {
+ .name = "INTC",
+ .irq_unmask = bcm3384_intc_irq_unmask,
+ .irq_mask = bcm3384_intc_irq_mask,
+ .irq_mask_ack = bcm3384_intc_irq_mask,
+};
+
+unsigned int get_c0_compare_int(void)
+{
+ return CP0_LEGACY_COMPARE_IRQ;
+}
+
+static void bcm3384_intc_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+ struct irq_domain *domain = irq_get_handler_data(irq);
+ struct bcm3384_intc *priv = domain->host_data;
+ unsigned long flags;
+ unsigned int idx;
+
+ for (idx = 0; idx < priv->n_words; idx++) {
+ unsigned long pending;
+ int hwirq;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ pending = __raw_readl(priv->reg[idx] + INTC_REG_STATUS) &
+ priv->enable[idx];
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
+ generic_handle_irq(irq_find_mapping(domain,
+ hwirq + idx * IRQS_PER_WORD));
+ }
+ }
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+ unsigned long pending =
+ (read_c0_status() & read_c0_cause() & ST0_IM) >> STATUSB_IP0;
+ int bit;
+
+ for_each_set_bit(bit, &pending, 8)
+ do_IRQ(MIPS_CPU_IRQ_BASE + bit);
+}
+
+static int intc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(irq, &bcm3384_intc_irq_chip, handle_level_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops irq_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = intc_map,
+};
+
+static int __init ioremap_one_pair(struct bcm3384_intc *priv,
+ struct device_node *node,
+ int idx)
+{
+ struct resource res;
+
+ if (of_address_to_resource(node, idx, &res))
+ return 0;
+
+ if (request_mem_region(res.start, resource_size(&res),
+ res.name) < 0)
+ pr_err("Failed to request INTC register region\n");
+
+ priv->reg[idx] = ioremap_nocache(res.start, resource_size(&res));
+ if (!priv->reg[idx])
+ panic("Failed to ioremap INTC register range");
+
+ /* start up with everything masked before we hook the parent IRQ */
+ __raw_writel(0, priv->reg[idx] + INTC_REG_ENABLE);
+ priv->enable[idx] = 0;
+
+ return IRQS_PER_WORD;
+}
+
+static int __init intc_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_domain *domain;
+ unsigned int parent_irq, n_irqs = 0;
+ struct bcm3384_intc *priv;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ panic("Failed to allocate bcm3384_intc struct");
+
+ spin_lock_init(&priv->lock);
+
+ parent_irq = irq_of_parse_and_map(node, 0);
+ if (!parent_irq)
+ panic("Failed to get INTC IRQ");
+
+ n_irqs += ioremap_one_pair(priv, node, 0);
+ n_irqs += ioremap_one_pair(priv, node, 1);
+
+ if (!n_irqs)
+ panic("Failed to map INTC registers");
+
+ priv->n_words = n_irqs / IRQS_PER_WORD;
+ domain = irq_domain_add_linear(node, n_irqs, &irq_domain_ops, priv);
+ if (!domain)
+ panic("Failed to add irqdomain");
+
+ irq_set_chained_handler(parent_irq, bcm3384_intc_irq_handler);
+ irq_set_handler_data(parent_irq, domain);
+
+ return 0;
+}
+
+static struct of_device_id of_irq_ids[] __initdata = {
+ { .compatible = "mti,cpu-interrupt-controller",
+ .data = mips_cpu_intc_init },
+ { .compatible = "brcm,bcm3384-intc",
+ .data = intc_of_init },
+ {},
+};
+
+void __init arch_init_irq(void)
+{
+ bmips_tp1_irqs = 0;
+ of_irq_init(of_irq_ids);
+}