1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-hip04.c b/drivers/irqchip/irq-hip04.c
new file mode 100644
index 000000000000..9c8f833522e6
--- /dev/null
+++ b/drivers/irqchip/irq-hip04.c
@@ -0,0 +1,424 @@
+/*
+ * Hisilicon HiP04 INTC
+ *
+ * Copyright (C) 2002-2014 ARM Limited.
+ * Copyright (c) 2013-2014 Hisilicon Ltd.
+ * Copyright (c) 2013-2014 Linaro Ltd.
+ *
+ * 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.
+ *
+ * Interrupt architecture for the HIP04 INTC:
+ *
+ * o There is one Interrupt Distributor, which receives interrupts
+ *   from system devices and sends them to the Interrupt Controllers.
+ *
+ * o There is one CPU Interface per CPU, which sends interrupts sent
+ *   by the Distributor, and interrupts generated locally, to the
+ *   associated CPU. The base address of the CPU interface is usually
+ *   aliased so that the same address points to different chips depending
+ *   on the CPU it is accessed from.
+ *
+ * Note that IRQs 0-31 are special - they are local to each CPU.
+ * As such, the enable set/clear, pending set/clear and active bit
+ * registers are banked per-cpu for these sources.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/cpu_pm.h>
+#include <linux/cpumask.h>
+#include <linux/io.h>
+#include <linux/of.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/irqchip/arm-gic.h>
+
+#include <asm/irq.h>
+#include <asm/exception.h>
+#include <asm/smp_plat.h>
+
+#include "irq-gic-common.h"
+#include "irqchip.h"
+
+#define HIP04_MAX_IRQS		510
+
+struct hip04_irq_data {
+	void __iomem *dist_base;
+	void __iomem *cpu_base;
+	struct irq_domain *domain;
+	unsigned int nr_irqs;
+};
+
+static DEFINE_RAW_SPINLOCK(irq_controller_lock);
+
+/*
+ * The GIC mapping of CPU interfaces does not necessarily match
+ * the logical CPU numbering.  Let's use a mapping as returned
+ * by the GIC itself.
+ */
+#define NR_HIP04_CPU_IF 16
+static u16 hip04_cpu_map[NR_HIP04_CPU_IF] __read_mostly;
+
+static struct hip04_irq_data hip04_data __read_mostly;
+
+static inline void __iomem *hip04_dist_base(struct irq_data *d)
+{
+	struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
+	return hip04_data->dist_base;
+}
+
+static inline void __iomem *hip04_cpu_base(struct irq_data *d)
+{
+	struct hip04_irq_data *hip04_data = irq_data_get_irq_chip_data(d);
+	return hip04_data->cpu_base;
+}
+
+static inline unsigned int hip04_irq(struct irq_data *d)
+{
+	return d->hwirq;
+}
+
+/*
+ * Routines to acknowledge, disable and enable interrupts
+ */
+static void hip04_mask_irq(struct irq_data *d)
+{
+	u32 mask = 1 << (hip04_irq(d) % 32);
+
+	raw_spin_lock(&irq_controller_lock);
+	writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_CLEAR +
+		       (hip04_irq(d) / 32) * 4);
+	raw_spin_unlock(&irq_controller_lock);
+}
+
+static void hip04_unmask_irq(struct irq_data *d)
+{
+	u32 mask = 1 << (hip04_irq(d) % 32);
+
+	raw_spin_lock(&irq_controller_lock);
+	writel_relaxed(mask, hip04_dist_base(d) + GIC_DIST_ENABLE_SET +
+		       (hip04_irq(d) / 32) * 4);
+	raw_spin_unlock(&irq_controller_lock);
+}
+
+static void hip04_eoi_irq(struct irq_data *d)
+{
+	writel_relaxed(hip04_irq(d), hip04_cpu_base(d) + GIC_CPU_EOI);
+}
+
+static int hip04_irq_set_type(struct irq_data *d, unsigned int type)
+{
+	void __iomem *base = hip04_dist_base(d);
+	unsigned int irq = hip04_irq(d);
+
+	/* Interrupt configuration for SGIs can't be changed */
+	if (irq < 16)
+		return -EINVAL;
+
+	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
+		return -EINVAL;
+
+	raw_spin_lock(&irq_controller_lock);
+
+	gic_configure_irq(irq, type, base, NULL);
+
+	raw_spin_unlock(&irq_controller_lock);
+
+	return 0;
+}
+
+#ifdef CONFIG_SMP
+static int hip04_irq_set_affinity(struct irq_data *d,
+				  const struct cpumask *mask_val,
+				  bool force)
+{
+	void __iomem *reg;
+	unsigned int cpu, shift = (hip04_irq(d) % 2) * 16;
+	u32 val, mask, bit;
+
+	if (!force)
+		cpu = cpumask_any_and(mask_val, cpu_online_mask);
+	else
+		cpu = cpumask_first(mask_val);
+
+	if (cpu >= NR_HIP04_CPU_IF || cpu >= nr_cpu_ids)
+		return -EINVAL;
+
+	raw_spin_lock(&irq_controller_lock);
+	reg = hip04_dist_base(d) + GIC_DIST_TARGET + ((hip04_irq(d) * 2) & ~3);
+	mask = 0xffff << shift;
+	bit = hip04_cpu_map[cpu] << shift;
+	val = readl_relaxed(reg) & ~mask;
+	writel_relaxed(val | bit, reg);
+	raw_spin_unlock(&irq_controller_lock);
+
+	return IRQ_SET_MASK_OK;
+}
+#endif
+
+static void __exception_irq_entry hip04_handle_irq(struct pt_regs *regs)
+{
+	u32 irqstat, irqnr;
+	void __iomem *cpu_base = hip04_data.cpu_base;
+
+	do {
+		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
+		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
+
+		if (likely(irqnr > 15 && irqnr <= HIP04_MAX_IRQS)) {
+			irqnr = irq_find_mapping(hip04_data.domain, irqnr);
+			handle_IRQ(irqnr, regs);
+			continue;
+		}
+		if (irqnr < 16) {
+			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
+#ifdef CONFIG_SMP
+			handle_IPI(irqnr, regs);
+#endif
+			continue;
+		}
+		break;
+	} while (1);
+}
+
+static struct irq_chip hip04_irq_chip = {
+	.name			= "HIP04 INTC",
+	.irq_mask		= hip04_mask_irq,
+	.irq_unmask		= hip04_unmask_irq,
+	.irq_eoi		= hip04_eoi_irq,
+	.irq_set_type		= hip04_irq_set_type,
+#ifdef CONFIG_SMP
+	.irq_set_affinity	= hip04_irq_set_affinity,
+#endif
+};
+
+static u16 hip04_get_cpumask(struct hip04_irq_data *intc)
+{
+	void __iomem *base = intc->dist_base;
+	u32 mask, i;
+
+	for (i = mask = 0; i < 32; i += 2) {
+		mask = readl_relaxed(base + GIC_DIST_TARGET + i * 2);
+		mask |= mask >> 16;
+		if (mask)
+			break;
+	}
+
+	if (!mask)
+		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
+
+	return mask;
+}
+
+static void __init hip04_irq_dist_init(struct hip04_irq_data *intc)
+{
+	unsigned int i;
+	u32 cpumask;
+	unsigned int nr_irqs = intc->nr_irqs;
+	void __iomem *base = intc->dist_base;
+
+	writel_relaxed(0, base + GIC_DIST_CTRL);
+
+	/*
+	 * Set all global interrupts to this CPU only.
+	 */
+	cpumask = hip04_get_cpumask(intc);
+	cpumask |= cpumask << 16;
+	for (i = 32; i < nr_irqs; i += 2)
+		writel_relaxed(cpumask, base + GIC_DIST_TARGET + ((i * 2) & ~3));
+
+	gic_dist_config(base, nr_irqs, NULL);
+
+	writel_relaxed(1, base + GIC_DIST_CTRL);
+}
+
+static void hip04_irq_cpu_init(struct hip04_irq_data *intc)
+{
+	void __iomem *dist_base = intc->dist_base;
+	void __iomem *base = intc->cpu_base;
+	unsigned int cpu_mask, cpu = smp_processor_id();
+	int i;
+
+	/*
+	 * Get what the GIC says our CPU mask is.
+	 */
+	BUG_ON(cpu >= NR_HIP04_CPU_IF);
+	cpu_mask = hip04_get_cpumask(intc);
+	hip04_cpu_map[cpu] = cpu_mask;
+
+	/*
+	 * Clear our mask from the other map entries in case they're
+	 * still undefined.
+	 */
+	for (i = 0; i < NR_HIP04_CPU_IF; i++)
+		if (i != cpu)
+			hip04_cpu_map[i] &= ~cpu_mask;
+
+	gic_cpu_config(dist_base, NULL);
+
+	writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
+	writel_relaxed(1, base + GIC_CPU_CTRL);
+}
+
+#ifdef CONFIG_SMP
+static void hip04_raise_softirq(const struct cpumask *mask, unsigned int irq)
+{
+	int cpu;
+	unsigned long flags, map = 0;
+
+	raw_spin_lock_irqsave(&irq_controller_lock, flags);
+
+	/* Convert our logical CPU mask into a physical one. */
+	for_each_cpu(cpu, mask)
+		map |= hip04_cpu_map[cpu];
+
+	/*
+	 * Ensure that stores to Normal memory are visible to the
+	 * other CPUs before they observe us issuing the IPI.
+	 */
+	dmb(ishst);
+
+	/* this always happens on GIC0 */
+	writel_relaxed(map << 8 | irq, hip04_data.dist_base + GIC_DIST_SOFTINT);
+
+	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
+}
+#endif
+
+static int hip04_irq_domain_map(struct irq_domain *d, unsigned int irq,
+				irq_hw_number_t hw)
+{
+	if (hw < 32) {
+		irq_set_percpu_devid(irq);
+		irq_set_chip_and_handler(irq, &hip04_irq_chip,
+					 handle_percpu_devid_irq);
+		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
+	} else {
+		irq_set_chip_and_handler(irq, &hip04_irq_chip,
+					 handle_fasteoi_irq);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+	}
+	irq_set_chip_data(irq, d->host_data);
+	return 0;
+}
+
+static int hip04_irq_domain_xlate(struct irq_domain *d,
+				  struct device_node *controller,
+				  const u32 *intspec, unsigned int intsize,
+				  unsigned long *out_hwirq,
+				  unsigned int *out_type)
+{
+	unsigned long ret = 0;
+
+	if (d->of_node != controller)
+		return -EINVAL;
+	if (intsize < 3)
+		return -EINVAL;
+
+	/* Get the interrupt number and add 16 to skip over SGIs */
+	*out_hwirq = intspec[1] + 16;
+
+	/* For SPIs, we need to add 16 more to get the irq ID number */
+	if (!intspec[0])
+		*out_hwirq += 16;
+
+	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+
+	return ret;
+}
+
+#ifdef CONFIG_SMP
+static int hip04_irq_secondary_init(struct notifier_block *nfb,
+				    unsigned long action,
+				    void *hcpu)
+{
+	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
+		hip04_irq_cpu_init(&hip04_data);
+	return NOTIFY_OK;
+}
+
+/*
+ * Notifier for enabling the INTC CPU interface. Set an arbitrarily high
+ * priority because the GIC needs to be up before the ARM generic timers.
+ */
+static struct notifier_block hip04_irq_cpu_notifier = {
+	.notifier_call	= hip04_irq_secondary_init,
+	.priority	= 100,
+};
+#endif
+
+static const struct irq_domain_ops hip04_irq_domain_ops = {
+	.map	= hip04_irq_domain_map,
+	.xlate	= hip04_irq_domain_xlate,
+};
+
+static int __init
+hip04_of_init(struct device_node *node, struct device_node *parent)
+{
+	irq_hw_number_t hwirq_base = 16;
+	int nr_irqs, irq_base, i;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	hip04_data.dist_base = of_iomap(node, 0);
+	WARN(!hip04_data.dist_base, "fail to map hip04 intc dist registers\n");
+
+	hip04_data.cpu_base = of_iomap(node, 1);
+	WARN(!hip04_data.cpu_base, "unable to map hip04 intc cpu registers\n");
+
+	/*
+	 * Initialize the CPU interface map to all CPUs.
+	 * It will be refined as each CPU probes its ID.
+	 */
+	for (i = 0; i < NR_HIP04_CPU_IF; i++)
+		hip04_cpu_map[i] = 0xff;
+
+	/*
+	 * Find out how many interrupts are supported.
+	 * The HIP04 INTC only supports up to 510 interrupt sources.
+	 */
+	nr_irqs = readl_relaxed(hip04_data.dist_base + GIC_DIST_CTR) & 0x1f;
+	nr_irqs = (nr_irqs + 1) * 32;
+	if (nr_irqs > HIP04_MAX_IRQS)
+		nr_irqs = HIP04_MAX_IRQS;
+	hip04_data.nr_irqs = nr_irqs;
+
+	nr_irqs -= hwirq_base; /* calculate # of irqs to allocate */
+
+	irq_base = irq_alloc_descs(-1, hwirq_base, nr_irqs, numa_node_id());
+	if (IS_ERR_VALUE(irq_base)) {
+		pr_err("failed to allocate IRQ numbers\n");
+		return -EINVAL;
+	}
+
+	hip04_data.domain = irq_domain_add_legacy(node, nr_irqs, irq_base,
+						  hwirq_base,
+						  &hip04_irq_domain_ops,
+						  &hip04_data);
+
+	if (WARN_ON(!hip04_data.domain))
+		return -EINVAL;
+
+#ifdef CONFIG_SMP
+	set_smp_cross_call(hip04_raise_softirq);
+	register_cpu_notifier(&hip04_irq_cpu_notifier);
+#endif
+	set_handle_irq(hip04_handle_irq);
+
+	hip04_irq_dist_init(&hip04_data);
+	hip04_irq_cpu_init(&hip04_data);
+
+	return 0;
+}
+IRQCHIP_DECLARE(hip04_intc, "hisilicon,hip04-intc", hip04_of_init);