1 files changed, 335 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
new file mode 100644
index 000000000000..d3b8c8be15f6
--- /dev/null
+++ b/drivers/irqchip/irq-bcm7038-l1.c
@@ -0,0 +1,335 @@
+/*
+ * Broadcom BCM7038 style Level 1 interrupt controller driver
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ * Author: Kevin Cernekee
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME	": " fmt
+
+#include <linux/bitops.h>
+#include <linux/kconfig.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/types.h>
+#include <linux/irqchip/chained_irq.h>
+
+#include "irqchip.h"
+
+#define IRQS_PER_WORD		32
+#define REG_BYTES_PER_IRQ_WORD	(sizeof(u32) * 4)
+#define MAX_WORDS		8
+
+struct bcm7038_l1_cpu;
+
+struct bcm7038_l1_chip {
+	raw_spinlock_t		lock;
+	unsigned int		n_words;
+	struct irq_domain	*domain;
+	struct bcm7038_l1_cpu	*cpus[NR_CPUS];
+	u8			affinity[MAX_WORDS * IRQS_PER_WORD];
+};
+
+struct bcm7038_l1_cpu {
+	void __iomem		*map_base;
+	u32			mask_cache[0];
+};
+
+/*
+ * STATUS/MASK_STATUS/MASK_SET/MASK_CLEAR are packed one right after another:
+ *
+ * 7038:
+ *   0x1000_1400: W0_STATUS
+ *   0x1000_1404: W1_STATUS
+ *   0x1000_1408: W0_MASK_STATUS
+ *   0x1000_140c: W1_MASK_STATUS
+ *   0x1000_1410: W0_MASK_SET
+ *   0x1000_1414: W1_MASK_SET
+ *   0x1000_1418: W0_MASK_CLEAR
+ *   0x1000_141c: W1_MASK_CLEAR
+ *
+ * 7445:
+ *   0xf03e_1500: W0_STATUS
+ *   0xf03e_1504: W1_STATUS
+ *   0xf03e_1508: W2_STATUS
+ *   0xf03e_150c: W3_STATUS
+ *   0xf03e_1510: W4_STATUS
+ *   0xf03e_1514: W0_MASK_STATUS
+ *   0xf03e_1518: W1_MASK_STATUS
+ *   [...]
+ */
+
+static inline unsigned int reg_status(struct bcm7038_l1_chip *intc,
+				      unsigned int word)
+{
+	return (0 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_status(struct bcm7038_l1_chip *intc,
+					   unsigned int word)
+{
+	return (1 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_set(struct bcm7038_l1_chip *intc,
+					unsigned int word)
+{
+	return (2 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_clr(struct bcm7038_l1_chip *intc,
+					unsigned int word)
+{
+	return (3 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline u32 l1_readl(void __iomem *reg)
+{
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		return ioread32be(reg);
+	else
+		return readl(reg);
+}
+
+static inline void l1_writel(u32 val, void __iomem *reg)
+{
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		iowrite32be(val, reg);
+	else
+		writel(val, reg);
+}
+
+static void bcm7038_l1_irq_handle(unsigned int irq, struct irq_desc *desc)
+{
+	struct bcm7038_l1_chip *intc = irq_desc_get_handler_data(desc);
+	struct bcm7038_l1_cpu *cpu;
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned int idx;
+
+#ifdef CONFIG_SMP
+	cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
+#else
+	cpu = intc->cpus[0];
+#endif
+
+	chained_irq_enter(chip, desc);
+
+	for (idx = 0; idx < intc->n_words; idx++) {
+		int base = idx * IRQS_PER_WORD;
+		unsigned long pending, flags;
+		int hwirq;
+
+		raw_spin_lock_irqsave(&intc->lock, flags);
+		pending = l1_readl(cpu->map_base + reg_status(intc, idx)) &
+			  ~cpu->mask_cache[idx];
+		raw_spin_unlock_irqrestore(&intc->lock, flags);
+
+		for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
+			generic_handle_irq(irq_find_mapping(intc->domain,
+							    base + hwirq));
+		}
+	}
+
+	chained_irq_exit(chip, desc);
+}
+
+static void __bcm7038_l1_unmask(struct irq_data *d, unsigned int cpu_idx)
+{
+	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+	u32 word = d->hwirq / IRQS_PER_WORD;
+	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);
+
+	intc->cpus[cpu_idx]->mask_cache[word] &= ~mask;
+	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
+			reg_mask_clr(intc, word));
+}
+
+static void __bcm7038_l1_mask(struct irq_data *d, unsigned int cpu_idx)
+{
+	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+	u32 word = d->hwirq / IRQS_PER_WORD;
+	u32 mask = BIT(d->hwirq % IRQS_PER_WORD);
+
+	intc->cpus[cpu_idx]->mask_cache[word] |= mask;
+	l1_writel(mask, intc->cpus[cpu_idx]->map_base +
+			reg_mask_set(intc, word));
+}
+
+static void bcm7038_l1_unmask(struct irq_data *d)
+{
+	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&intc->lock, flags);
+	__bcm7038_l1_unmask(d, intc->affinity[d->hwirq]);
+	raw_spin_unlock_irqrestore(&intc->lock, flags);
+}
+
+static void bcm7038_l1_mask(struct irq_data *d)
+{
+	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&intc->lock, flags);
+	__bcm7038_l1_mask(d, intc->affinity[d->hwirq]);
+	raw_spin_unlock_irqrestore(&intc->lock, flags);
+}
+
+static int bcm7038_l1_set_affinity(struct irq_data *d,
+				   const struct cpumask *dest,
+				   bool force)
+{
+	struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+	unsigned long flags;
+	irq_hw_number_t hw = d->hwirq;
+	u32 word = hw / IRQS_PER_WORD;
+	u32 mask = BIT(hw % IRQS_PER_WORD);
+	unsigned int first_cpu = cpumask_any_and(dest, cpu_online_mask);
+	bool was_disabled;
+
+	raw_spin_lock_irqsave(&intc->lock, flags);
+
+	was_disabled = !!(intc->cpus[intc->affinity[hw]]->mask_cache[word] &
+			  mask);
+	__bcm7038_l1_mask(d, intc->affinity[hw]);
+	intc->affinity[hw] = first_cpu;
+	if (!was_disabled)
+		__bcm7038_l1_unmask(d, first_cpu);
+
+	raw_spin_unlock_irqrestore(&intc->lock, flags);
+	return 0;
+}
+
+static int __init bcm7038_l1_init_one(struct device_node *dn,
+				      unsigned int idx,
+				      struct bcm7038_l1_chip *intc)
+{
+	struct resource res;
+	resource_size_t sz;
+	struct bcm7038_l1_cpu *cpu;
+	unsigned int i, n_words, parent_irq;
+
+	if (of_address_to_resource(dn, idx, &res))
+		return -EINVAL;
+	sz = resource_size(&res);
+	n_words = sz / REG_BYTES_PER_IRQ_WORD;
+
+	if (n_words > MAX_WORDS)
+		return -EINVAL;
+	else if (!intc->n_words)
+		intc->n_words = n_words;
+	else if (intc->n_words != n_words)
+		return -EINVAL;
+
+	cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
+					GFP_KERNEL);
+	if (!cpu)
+		return -ENOMEM;
+
+	cpu->map_base = ioremap(res.start, sz);
+	if (!cpu->map_base)
+		return -ENOMEM;
+
+	for (i = 0; i < n_words; i++) {
+		l1_writel(0xffffffff, cpu->map_base + reg_mask_set(intc, i));
+		cpu->mask_cache[i] = 0xffffffff;
+	}
+
+	parent_irq = irq_of_parse_and_map(dn, idx);
+	if (!parent_irq) {
+		pr_err("failed to map parent interrupt %d\n", parent_irq);
+		return -EINVAL;
+	}
+	irq_set_handler_data(parent_irq, intc);
+	irq_set_chained_handler(parent_irq, bcm7038_l1_irq_handle);
+
+	return 0;
+}
+
+static struct irq_chip bcm7038_l1_irq_chip = {
+	.name			= "bcm7038-l1",
+	.irq_mask		= bcm7038_l1_mask,
+	.irq_unmask		= bcm7038_l1_unmask,
+	.irq_set_affinity	= bcm7038_l1_set_affinity,
+};
+
+static int bcm7038_l1_map(struct irq_domain *d, unsigned int virq,
+			  irq_hw_number_t hw_irq)
+{
+	irq_set_chip_and_handler(virq, &bcm7038_l1_irq_chip, handle_level_irq);
+	irq_set_chip_data(virq, d->host_data);
+	return 0;
+}
+
+static const struct irq_domain_ops bcm7038_l1_domain_ops = {
+	.xlate			= irq_domain_xlate_onecell,
+	.map			= bcm7038_l1_map,
+};
+
+int __init bcm7038_l1_of_init(struct device_node *dn,
+			      struct device_node *parent)
+{
+	struct bcm7038_l1_chip *intc;
+	int idx, ret;
+
+	intc = kzalloc(sizeof(*intc), GFP_KERNEL);
+	if (!intc)
+		return -ENOMEM;
+
+	raw_spin_lock_init(&intc->lock);
+	for_each_possible_cpu(idx) {
+		ret = bcm7038_l1_init_one(dn, idx, intc);
+		if (ret < 0) {
+			if (idx)
+				break;
+			pr_err("failed to remap intc L1 registers\n");
+			goto out_free;
+		}
+	}
+
+	intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words,
+					     &bcm7038_l1_domain_ops,
+					     intc);
+	if (!intc->domain) {
+		ret = -ENOMEM;
+		goto out_unmap;
+	}
+
+	pr_info("registered BCM7038 L1 intc (mem: 0x%p, IRQs: %d)\n",
+		intc->cpus[0]->map_base, IRQS_PER_WORD * intc->n_words);
+
+	return 0;
+
+out_unmap:
+	for_each_possible_cpu(idx) {
+		struct bcm7038_l1_cpu *cpu = intc->cpus[idx];
+
+		if (cpu) {
+			if (cpu->map_base)
+				iounmap(cpu->map_base);
+			kfree(cpu);
+		}
+	}
+out_free:
+	kfree(intc);
+	return ret;
+}
+
+IRQCHIP_DECLARE(bcm7038_l1, "brcm,bcm7038-l1-intc", bcm7038_l1_of_init);