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-rw-r--r--arch/xtensa/kernel/irq.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
new file mode 100644
index 000000000..80cc9770a
--- /dev/null
+++ b/arch/xtensa/kernel/irq.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/xtensa/kernel/irq.c
+ *
+ * Xtensa built-in interrupt controller and some generic functions copied
+ * from i386.
+ *
+ * Copyright (C) 2002 - 2013 Tensilica, Inc.
+ * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
+ *
+ *
+ * Chris Zankel <chris@zankel.net>
+ * Kevin Chea
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel_stat.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/xtensa-mx.h>
+#include <linux/irqchip/xtensa-pic.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+
+#include <asm/mxregs.h>
+#include <linux/uaccess.h>
+#include <asm/platform.h>
+
+DECLARE_PER_CPU(unsigned long, nmi_count);
+
+asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
+{
+ int irq = irq_find_mapping(NULL, hwirq);
+
+#ifdef CONFIG_DEBUG_STACKOVERFLOW
+ /* Debugging check for stack overflow: is there less than 1KB free? */
+ {
+ unsigned long sp;
+
+ __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp));
+ sp &= THREAD_SIZE - 1;
+
+ if (unlikely(sp < (sizeof(thread_info) + 1024)))
+ printk("Stack overflow in do_IRQ: %ld\n",
+ sp - sizeof(struct thread_info));
+ }
+#endif
+ generic_handle_irq(irq);
+}
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+ unsigned cpu __maybe_unused;
+#ifdef CONFIG_SMP
+ show_ipi_list(p, prec);
+#endif
+#if XTENSA_FAKE_NMI
+ seq_printf(p, "%*s:", prec, "NMI");
+ for_each_online_cpu(cpu)
+ seq_printf(p, " %10lu", per_cpu(nmi_count, cpu));
+ seq_puts(p, " Non-maskable interrupts\n");
+#endif
+ return 0;
+}
+
+int xtensa_irq_domain_xlate(const u32 *intspec, unsigned int intsize,
+ unsigned long int_irq, unsigned long ext_irq,
+ unsigned long *out_hwirq, unsigned int *out_type)
+{
+ if (WARN_ON(intsize < 1 || intsize > 2))
+ return -EINVAL;
+ if (intsize == 2 && intspec[1] == 1) {
+ int_irq = xtensa_map_ext_irq(ext_irq);
+ if (int_irq < XCHAL_NUM_INTERRUPTS)
+ *out_hwirq = int_irq;
+ else
+ return -EINVAL;
+ } else {
+ *out_hwirq = int_irq;
+ }
+ *out_type = IRQ_TYPE_NONE;
+ return 0;
+}
+
+int xtensa_irq_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ struct irq_chip *irq_chip = d->host_data;
+ u32 mask = 1 << hw;
+
+ if (mask & XCHAL_INTTYPE_MASK_SOFTWARE) {
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_simple_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE) {
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_edge_irq, "edge");
+ irq_clear_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL) {
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_level_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_TIMER) {
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_percpu_irq, "timer");
+ irq_clear_status_flags(irq, IRQ_LEVEL);
+#ifdef XCHAL_INTTYPE_MASK_PROFILING
+ } else if (mask & XCHAL_INTTYPE_MASK_PROFILING) {
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_percpu_irq, "profiling");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+#endif
+ } else {/* XCHAL_INTTYPE_MASK_WRITE_ERROR */
+ /* XCHAL_INTTYPE_MASK_NMI */
+ irq_set_chip_and_handler_name(irq, irq_chip,
+ handle_level_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ }
+ return 0;
+}
+
+unsigned xtensa_map_ext_irq(unsigned ext_irq)
+{
+ unsigned mask = XCHAL_INTTYPE_MASK_EXTERN_EDGE |
+ XCHAL_INTTYPE_MASK_EXTERN_LEVEL;
+ unsigned i;
+
+ for (i = 0; mask; ++i, mask >>= 1) {
+ if ((mask & 1) && ext_irq-- == 0)
+ return i;
+ }
+ return XCHAL_NUM_INTERRUPTS;
+}
+
+unsigned xtensa_get_ext_irq_no(unsigned irq)
+{
+ unsigned mask = (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
+ XCHAL_INTTYPE_MASK_EXTERN_LEVEL) &
+ ((1u << irq) - 1);
+ return hweight32(mask);
+}
+
+void __init init_IRQ(void)
+{
+#ifdef CONFIG_USE_OF
+ irqchip_init();
+#else
+#ifdef CONFIG_HAVE_SMP
+ xtensa_mx_init_legacy(NULL);
+#else
+ xtensa_pic_init_legacy(NULL);
+#endif
+#endif
+
+#ifdef CONFIG_SMP
+ ipi_init();
+#endif
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * The CPU has been marked offline. Migrate IRQs off this CPU. If
+ * the affinity settings do not allow other CPUs, force them onto any
+ * available CPU.
+ */
+void migrate_irqs(void)
+{
+ unsigned int i, cpu = smp_processor_id();
+
+ for_each_active_irq(i) {
+ struct irq_data *data = irq_get_irq_data(i);
+ struct cpumask *mask;
+ unsigned int newcpu;
+
+ if (irqd_is_per_cpu(data))
+ continue;
+
+ mask = irq_data_get_affinity_mask(data);
+ if (!cpumask_test_cpu(cpu, mask))
+ continue;
+
+ newcpu = cpumask_any_and(mask, cpu_online_mask);
+
+ if (newcpu >= nr_cpu_ids) {
+ pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
+ i, cpu);
+
+ cpumask_setall(mask);
+ }
+ irq_set_affinity(i, mask);
+ }
+}
+#endif /* CONFIG_HOTPLUG_CPU */