--- /dev/null
+/*
+ * 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.
+ *
+ * Copyright (C) 2010 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+#include <linux/irqdomain.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/bootinfo.h>
+#include <asm/irq_cpu.h>
+
+#include <lantiq_soc.h>
+#include <irq.h>
+
+/* register definitions - internal irqs */
+#define LTQ_ICU_IM0_ISR 0x0000
+#define LTQ_ICU_IM0_IER 0x0008
+#define LTQ_ICU_IM0_IOSR 0x0010
+#define LTQ_ICU_IM0_IRSR 0x0018
+#define LTQ_ICU_IM0_IMR 0x0020
+#define LTQ_ICU_IM1_ISR 0x0028
+#define LTQ_ICU_OFFSET (LTQ_ICU_IM1_ISR - LTQ_ICU_IM0_ISR)
+
+/* register definitions - external irqs */
+#define LTQ_EIU_EXIN_C 0x0000
+#define LTQ_EIU_EXIN_INIC 0x0004
+#define LTQ_EIU_EXIN_INC 0x0008
+#define LTQ_EIU_EXIN_INEN 0x000C
+
+/* number of external interrupts */
+#define MAX_EIU 6
+
+/* the performance counter */
+#define LTQ_PERF_IRQ (INT_NUM_IM4_IRL0 + 31)
+
+/*
+ * irqs generated by devices attached to the EBU need to be acked in
+ * a special manner
+ */
+#define LTQ_ICU_EBU_IRQ 22
+
+#define ltq_icu_w32(m, x, y) ltq_w32((x), ltq_icu_membase[m] + (y))
+#define ltq_icu_r32(m, x) ltq_r32(ltq_icu_membase[m] + (x))
+
+#define ltq_eiu_w32(x, y) ltq_w32((x), ltq_eiu_membase + (y))
+#define ltq_eiu_r32(x) ltq_r32(ltq_eiu_membase + (x))
+
+/* our 2 ipi interrupts for VSMP */
+#define MIPS_CPU_IPI_RESCHED_IRQ 0
+#define MIPS_CPU_IPI_CALL_IRQ 1
+
+/* we have a cascade of 8 irqs */
+#define MIPS_CPU_IRQ_CASCADE 8
+
+#ifdef CONFIG_MIPS_MT_SMP
+int gic_present;
+#endif
+
+static int exin_avail;
+static struct resource ltq_eiu_irq[MAX_EIU];
+static void __iomem *ltq_icu_membase[MAX_IM];
+static void __iomem *ltq_eiu_membase;
+static struct irq_domain *ltq_domain;
+static int ltq_perfcount_irq;
+
+int ltq_eiu_get_irq(int exin)
+{
+ if (exin < exin_avail)
+ return ltq_eiu_irq[exin].start;
+ return -1;
+}
+
+void ltq_disable_irq(struct irq_data *d)
+{
+ u32 ier = LTQ_ICU_IM0_IER;
+ int offset = d->hwirq - MIPS_CPU_IRQ_CASCADE;
+ int im = offset / INT_NUM_IM_OFFSET;
+
+ offset %= INT_NUM_IM_OFFSET;
+ ltq_icu_w32(im, ltq_icu_r32(im, ier) & ~BIT(offset), ier);
+}
+
+void ltq_mask_and_ack_irq(struct irq_data *d)
+{
+ u32 ier = LTQ_ICU_IM0_IER;
+ u32 isr = LTQ_ICU_IM0_ISR;
+ int offset = d->hwirq - MIPS_CPU_IRQ_CASCADE;
+ int im = offset / INT_NUM_IM_OFFSET;
+
+ offset %= INT_NUM_IM_OFFSET;
+ ltq_icu_w32(im, ltq_icu_r32(im, ier) & ~BIT(offset), ier);
+ ltq_icu_w32(im, BIT(offset), isr);
+}
+
+static void ltq_ack_irq(struct irq_data *d)
+{
+ u32 isr = LTQ_ICU_IM0_ISR;
+ int offset = d->hwirq - MIPS_CPU_IRQ_CASCADE;
+ int im = offset / INT_NUM_IM_OFFSET;
+
+ offset %= INT_NUM_IM_OFFSET;
+ ltq_icu_w32(im, BIT(offset), isr);
+}
+
+void ltq_enable_irq(struct irq_data *d)
+{
+ u32 ier = LTQ_ICU_IM0_IER;
+ int offset = d->hwirq - MIPS_CPU_IRQ_CASCADE;
+ int im = offset / INT_NUM_IM_OFFSET;
+
+ offset %= INT_NUM_IM_OFFSET;
+ ltq_icu_w32(im, ltq_icu_r32(im, ier) | BIT(offset), ier);
+}
+
+static int ltq_eiu_settype(struct irq_data *d, unsigned int type)
+{
+ int i;
+
+ for (i = 0; i < MAX_EIU; i++) {
+ if (d->hwirq == ltq_eiu_irq[i].start) {
+ int val = 0;
+ int edge = 0;
+
+ switch (type) {
+ case IRQF_TRIGGER_NONE:
+ break;
+ case IRQF_TRIGGER_RISING:
+ val = 1;
+ edge = 1;
+ break;
+ case IRQF_TRIGGER_FALLING:
+ val = 2;
+ edge = 1;
+ break;
+ case IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING:
+ val = 3;
+ edge = 1;
+ break;
+ case IRQF_TRIGGER_HIGH:
+ val = 5;
+ break;
+ case IRQF_TRIGGER_LOW:
+ val = 6;
+ break;
+ default:
+ pr_err("invalid type %d for irq %ld\n",
+ type, d->hwirq);
+ return -EINVAL;
+ }
+
+ if (edge)
+ irq_set_handler(d->hwirq, handle_edge_irq);
+
+ ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_C) |
+ (val << (i * 4)), LTQ_EIU_EXIN_C);
+ }
+ }
+
+ return 0;
+}
+
+static unsigned int ltq_startup_eiu_irq(struct irq_data *d)
+{
+ int i;
+
+ ltq_enable_irq(d);
+ for (i = 0; i < MAX_EIU; i++) {
+ if (d->hwirq == ltq_eiu_irq[i].start) {
+ /* by default we are low level triggered */
+ ltq_eiu_settype(d, IRQF_TRIGGER_LOW);
+ /* clear all pending */
+ ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INC) & ~BIT(i),
+ LTQ_EIU_EXIN_INC);
+ /* enable */
+ ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) | BIT(i),
+ LTQ_EIU_EXIN_INEN);
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static void ltq_shutdown_eiu_irq(struct irq_data *d)
+{
+ int i;
+
+ ltq_disable_irq(d);
+ for (i = 0; i < MAX_EIU; i++) {
+ if (d->hwirq == ltq_eiu_irq[i].start) {
+ /* disable */
+ ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) & ~BIT(i),
+ LTQ_EIU_EXIN_INEN);
+ break;
+ }
+ }
+}
+
+static struct irq_chip ltq_irq_type = {
+ "icu",
+ .irq_enable = ltq_enable_irq,
+ .irq_disable = ltq_disable_irq,
+ .irq_unmask = ltq_enable_irq,
+ .irq_ack = ltq_ack_irq,
+ .irq_mask = ltq_disable_irq,
+ .irq_mask_ack = ltq_mask_and_ack_irq,
+};
+
+static struct irq_chip ltq_eiu_type = {
+ "eiu",
+ .irq_startup = ltq_startup_eiu_irq,
+ .irq_shutdown = ltq_shutdown_eiu_irq,
+ .irq_enable = ltq_enable_irq,
+ .irq_disable = ltq_disable_irq,
+ .irq_unmask = ltq_enable_irq,
+ .irq_ack = ltq_ack_irq,
+ .irq_mask = ltq_disable_irq,
+ .irq_mask_ack = ltq_mask_and_ack_irq,
+ .irq_set_type = ltq_eiu_settype,
+};
+
+static void ltq_hw_irqdispatch(int module)
+{
+ u32 irq;
+
+ irq = ltq_icu_r32(module, LTQ_ICU_IM0_IOSR);
+ if (irq == 0)
+ return;
+
+ /*
+ * silicon bug causes only the msb set to 1 to be valid. all
+ * other bits might be bogus
+ */
+ irq = __fls(irq);
+ do_IRQ((int)irq + MIPS_CPU_IRQ_CASCADE + (INT_NUM_IM_OFFSET * module));
+
+ /* if this is a EBU irq, we need to ack it or get a deadlock */
+ if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
+ ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_ISTAT) | 0x10,
+ LTQ_EBU_PCC_ISTAT);
+}
+
+#define DEFINE_HWx_IRQDISPATCH(x) \
+ static void ltq_hw ## x ## _irqdispatch(void) \
+ { \
+ ltq_hw_irqdispatch(x); \
+ }
+DEFINE_HWx_IRQDISPATCH(0)
+DEFINE_HWx_IRQDISPATCH(1)
+DEFINE_HWx_IRQDISPATCH(2)
+DEFINE_HWx_IRQDISPATCH(3)
+DEFINE_HWx_IRQDISPATCH(4)
+
+#if MIPS_CPU_TIMER_IRQ == 7
+static void ltq_hw5_irqdispatch(void)
+{
+ do_IRQ(MIPS_CPU_TIMER_IRQ);
+}
+#else
+DEFINE_HWx_IRQDISPATCH(5)
+#endif
+
+#ifdef CONFIG_MIPS_MT_SMP
+void __init arch_init_ipiirq(int irq, struct irqaction *action)
+{
+ setup_irq(irq, action);
+ irq_set_handler(irq, handle_percpu_irq);
+}
+
+static void ltq_sw0_irqdispatch(void)
+{
+ do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_RESCHED_IRQ);
+}
+
+static void ltq_sw1_irqdispatch(void)
+{
+ do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_CALL_IRQ);
+}
+static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id)
+{
+ scheduler_ipi();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ipi_call_interrupt(int irq, void *dev_id)
+{
+ smp_call_function_interrupt();
+ return IRQ_HANDLED;
+}
+
+static struct irqaction irq_resched = {
+ .handler = ipi_resched_interrupt,
+ .flags = IRQF_PERCPU,
+ .name = "IPI_resched"
+};
+
+static struct irqaction irq_call = {
+ .handler = ipi_call_interrupt,
+ .flags = IRQF_PERCPU,
+ .name = "IPI_call"
+};
+#endif
+
+asmlinkage void plat_irq_dispatch(void)
+{
+ unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
+ unsigned int i;
+
+ if ((MIPS_CPU_TIMER_IRQ == 7) && (pending & CAUSEF_IP7)) {
+ do_IRQ(MIPS_CPU_TIMER_IRQ);
+ goto out;
+ } else {
+ for (i = 0; i < MAX_IM; i++) {
+ if (pending & (CAUSEF_IP2 << i)) {
+ ltq_hw_irqdispatch(i);
+ goto out;
+ }
+ }
+ }
+ pr_alert("Spurious IRQ: CAUSE=0x%08x\n", read_c0_status());
+
+out:
+ return;
+}
+
+static int icu_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+{
+ struct irq_chip *chip = <q_irq_type;
+ int i;
+
+ if (hw < MIPS_CPU_IRQ_CASCADE)
+ return 0;
+
+ for (i = 0; i < exin_avail; i++)
+ if (hw == ltq_eiu_irq[i].start)
+ chip = <q_eiu_type;
+
+ irq_set_chip_and_handler(hw, chip, handle_level_irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops irq_domain_ops = {
+ .xlate = irq_domain_xlate_onetwocell,
+ .map = icu_map,
+};
+
+static struct irqaction cascade = {
+ .handler = no_action,
+ .name = "cascade",
+};
+
+int __init icu_of_init(struct device_node *node, struct device_node *parent)
+{
+ struct device_node *eiu_node;
+ struct resource res;
+ int i, ret;
+
+ for (i = 0; i < MAX_IM; i++) {
+ if (of_address_to_resource(node, i, &res))
+ panic("Failed to get icu memory range");
+
+ if (request_mem_region(res.start, resource_size(&res),
+ res.name) < 0)
+ pr_err("Failed to request icu memory");
+
+ ltq_icu_membase[i] = ioremap_nocache(res.start,
+ resource_size(&res));
+ if (!ltq_icu_membase[i])
+ panic("Failed to remap icu memory");
+ }
+
+ /* turn off all irqs by default */
+ for (i = 0; i < MAX_IM; i++) {
+ /* make sure all irqs are turned off by default */
+ ltq_icu_w32(i, 0, LTQ_ICU_IM0_IER);
+ /* clear all possibly pending interrupts */
+ ltq_icu_w32(i, ~0, LTQ_ICU_IM0_ISR);
+ }
+
+ mips_cpu_irq_init();
+
+ for (i = 0; i < MAX_IM; i++)
+ setup_irq(i + 2, &cascade);
+
+ if (cpu_has_vint) {
+ pr_info("Setting up vectored interrupts\n");
+ set_vi_handler(2, ltq_hw0_irqdispatch);
+ set_vi_handler(3, ltq_hw1_irqdispatch);
+ set_vi_handler(4, ltq_hw2_irqdispatch);
+ set_vi_handler(5, ltq_hw3_irqdispatch);
+ set_vi_handler(6, ltq_hw4_irqdispatch);
+ set_vi_handler(7, ltq_hw5_irqdispatch);
+ }
+
+ ltq_domain = irq_domain_add_linear(node,
+ (MAX_IM * INT_NUM_IM_OFFSET) + MIPS_CPU_IRQ_CASCADE,
+ &irq_domain_ops, 0);
+
+#if defined(CONFIG_MIPS_MT_SMP)
+ if (cpu_has_vint) {
+ pr_info("Setting up IPI vectored interrupts\n");
+ set_vi_handler(MIPS_CPU_IPI_RESCHED_IRQ, ltq_sw0_irqdispatch);
+ set_vi_handler(MIPS_CPU_IPI_CALL_IRQ, ltq_sw1_irqdispatch);
+ }
+ arch_init_ipiirq(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_RESCHED_IRQ,
+ &irq_resched);
+ arch_init_ipiirq(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_CALL_IRQ, &irq_call);
+#endif
+
+#ifndef CONFIG_MIPS_MT_SMP
+ set_c0_status(IE_IRQ0 | IE_IRQ1 | IE_IRQ2 |
+ IE_IRQ3 | IE_IRQ4 | IE_IRQ5);
+#else
+ set_c0_status(IE_SW0 | IE_SW1 | IE_IRQ0 | IE_IRQ1 |
+ IE_IRQ2 | IE_IRQ3 | IE_IRQ4 | IE_IRQ5);
+#endif
+
+ /* tell oprofile which irq to use */
+ ltq_perfcount_irq = irq_create_mapping(ltq_domain, LTQ_PERF_IRQ);
+
+ /*
+ * if the timer irq is not one of the mips irqs we need to
+ * create a mapping
+ */
+ if (MIPS_CPU_TIMER_IRQ != 7)
+ irq_create_mapping(ltq_domain, MIPS_CPU_TIMER_IRQ);
+
+ /* the external interrupts are optional and xway only */
+ eiu_node = of_find_compatible_node(NULL, NULL, "lantiq,eiu-xway");
+ if (eiu_node && !of_address_to_resource(eiu_node, 0, &res)) {
+ /* find out how many external irq sources we have */
+ exin_avail = of_irq_count(eiu_node);
+
+ if (exin_avail > MAX_EIU)
+ exin_avail = MAX_EIU;
+
+ ret = of_irq_to_resource_table(eiu_node,
+ ltq_eiu_irq, exin_avail);
+ if (ret != exin_avail)
+ panic("failed to load external irq resources");
+
+ if (request_mem_region(res.start, resource_size(&res),
+ res.name) < 0)
+ pr_err("Failed to request eiu memory");
+
+ ltq_eiu_membase = ioremap_nocache(res.start,
+ resource_size(&res));
+ if (!ltq_eiu_membase)
+ panic("Failed to remap eiu memory");
+ }
+
+ return 0;
+}
+
+int get_c0_perfcount_int(void)
+{
+ return ltq_perfcount_irq;
+}
+
+unsigned int get_c0_compare_int(void)
+{
+ return MIPS_CPU_TIMER_IRQ;
+}
+
+static struct of_device_id __initdata of_irq_ids[] = {
+ { .compatible = "lantiq,icu", .data = icu_of_init },
+ {},
+};
+
+void __init arch_init_irq(void)
+{
+ of_irq_init(of_irq_ids);
+}
Code Review / kvmfornfv.git / blobdiff