arch/xtensa/kernel/irq.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/arch/xtensa/kernel/irq.c
   4  *
   5  * Xtensa built-in interrupt controller and some generic functions copied
   6  * from i386.
   7  *
   8  * Copyright (C) 2002 - 2013 Tensilica, Inc.
   9  * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
  10  *
  11  *
  12  * Chris Zankel <chris@zankel.net>
  13  * Kevin Chea
  14  *
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/irq.h>
  21 #include <linux/kernel_stat.h>
  22 #include <linux/irqchip.h>
  23 #include <linux/irqchip/xtensa-mx.h>
  24 #include <linux/irqchip/xtensa-pic.h>
  25 #include <linux/irqdomain.h>
  26 #include <linux/of.h>
  27
  28 #include <asm/mxregs.h>
  29 #include <linux/uaccess.h>
  30 #include <asm/platform.h>
  31
  32 DECLARE_PER_CPU(unsigned long, nmi_count);
  33
  34 asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
  35 {
  36         int irq = irq_find_mapping(NULL, hwirq);
  37
  38 #ifdef CONFIG_DEBUG_STACKOVERFLOW
  39         /* Debugging check for stack overflow: is there less than 1KB free? */
  40         {
  41                 unsigned long sp;
  42
  43                 __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp));
  44                 sp &= THREAD_SIZE - 1;
  45
  46                 if (unlikely(sp < (sizeof(thread_info) + 1024)))
  47                         printk("Stack overflow in do_IRQ: %ld\n",
  48                                sp - sizeof(struct thread_info));
  49         }
  50 #endif
  51         generic_handle_irq(irq);
  52 }
  53
  54 int arch_show_interrupts(struct seq_file *p, int prec)
  55 {
  56         unsigned cpu __maybe_unused;
  57 #ifdef CONFIG_SMP
  58         show_ipi_list(p, prec);
  59 #endif
  60 #if XTENSA_FAKE_NMI
  61         seq_printf(p, "%*s:", prec, "NMI");
  62         for_each_online_cpu(cpu)
  63                 seq_printf(p, " %10lu", per_cpu(nmi_count, cpu));
  64         seq_puts(p, "   Non-maskable interrupts\n");
  65 #endif
  66         return 0;
  67 }
  68
  69 int xtensa_irq_domain_xlate(const u32 *intspec, unsigned int intsize,
  70                 unsigned long int_irq, unsigned long ext_irq,
  71                 unsigned long *out_hwirq, unsigned int *out_type)
  72 {
  73         if (WARN_ON(intsize < 1 || intsize > 2))
  74                 return -EINVAL;
  75         if (intsize == 2 && intspec[1] == 1) {
  76                 int_irq = xtensa_map_ext_irq(ext_irq);
  77                 if (int_irq < XCHAL_NUM_INTERRUPTS)
  78                         *out_hwirq = int_irq;
  79                 else
  80                         return -EINVAL;
  81         } else {
  82                 *out_hwirq = int_irq;
  83         }
  84         *out_type = IRQ_TYPE_NONE;
  85         return 0;
  86 }
  87
  88 int xtensa_irq_map(struct irq_domain *d, unsigned int irq,
  89                 irq_hw_number_t hw)
  90 {
  91         struct irq_chip *irq_chip = d->host_data;
  92         u32 mask = 1 << hw;
  93
  94         if (mask & XCHAL_INTTYPE_MASK_SOFTWARE) {
  95                 irq_set_chip_and_handler_name(irq, irq_chip,
  96                                 handle_simple_irq, "level");
  97                 irq_set_status_flags(irq, IRQ_LEVEL);
  98         } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE) {
  99                 irq_set_chip_and_handler_name(irq, irq_chip,
 100                                 handle_edge_irq, "edge");
 101                 irq_clear_status_flags(irq, IRQ_LEVEL);
 102         } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL) {
 103                 irq_set_chip_and_handler_name(irq, irq_chip,
 104                                 handle_level_irq, "level");
 105                 irq_set_status_flags(irq, IRQ_LEVEL);
 106         } else if (mask & XCHAL_INTTYPE_MASK_TIMER) {
 107                 irq_set_chip_and_handler_name(irq, irq_chip,
 108                                 handle_percpu_irq, "timer");
 109                 irq_clear_status_flags(irq, IRQ_LEVEL);
 110 #ifdef XCHAL_INTTYPE_MASK_PROFILING
 111         } else if (mask & XCHAL_INTTYPE_MASK_PROFILING) {
 112                 irq_set_chip_and_handler_name(irq, irq_chip,
 113                                 handle_percpu_irq, "profiling");
 114                 irq_set_status_flags(irq, IRQ_LEVEL);
 115 #endif
 116         } else {/* XCHAL_INTTYPE_MASK_WRITE_ERROR */
 117                 /* XCHAL_INTTYPE_MASK_NMI */
 118                 irq_set_chip_and_handler_name(irq, irq_chip,
 119                                 handle_level_irq, "level");
 120                 irq_set_status_flags(irq, IRQ_LEVEL);
 121         }
 122         return 0;
 123 }
 124
 125 unsigned xtensa_map_ext_irq(unsigned ext_irq)
 126 {
 127         unsigned mask = XCHAL_INTTYPE_MASK_EXTERN_EDGE |
 128                 XCHAL_INTTYPE_MASK_EXTERN_LEVEL;
 129         unsigned i;
 130
 131         for (i = 0; mask; ++i, mask >>= 1) {
 132                 if ((mask & 1) && ext_irq-- == 0)
 133                         return i;
 134         }
 135         return XCHAL_NUM_INTERRUPTS;
 136 }
 137
 138 unsigned xtensa_get_ext_irq_no(unsigned irq)
 139 {
 140         unsigned mask = (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
 141                 XCHAL_INTTYPE_MASK_EXTERN_LEVEL) &
 142                 ((1u << irq) - 1);
 143         return hweight32(mask);
 144 }
 145
 146 void __init init_IRQ(void)
 147 {
 148 #ifdef CONFIG_OF
 149         irqchip_init();
 150 #else
 151 #ifdef CONFIG_HAVE_SMP
 152         xtensa_mx_init_legacy(NULL);
 153 #else
 154         xtensa_pic_init_legacy(NULL);
 155 #endif
 156 #endif
 157
 158 #ifdef CONFIG_SMP
 159         ipi_init();
 160 #endif
 161         variant_init_irq();
 162 }
 163
 164 #ifdef CONFIG_HOTPLUG_CPU
 165 /*
 166  * The CPU has been marked offline.  Migrate IRQs off this CPU.  If
 167  * the affinity settings do not allow other CPUs, force them onto any
 168  * available CPU.
 169  */
 170 void migrate_irqs(void)
 171 {
 172         unsigned int i, cpu = smp_processor_id();
 173
 174         for_each_active_irq(i) {
 175                 struct irq_data *data = irq_get_irq_data(i);
 176                 struct cpumask *mask;
 177                 unsigned int newcpu;
 178
 179                 if (irqd_is_per_cpu(data))
 180                         continue;
 181
 182                 mask = irq_data_get_affinity_mask(data);
 183                 if (!cpumask_test_cpu(cpu, mask))
 184                         continue;
 185
 186                 newcpu = cpumask_any_and(mask, cpu_online_mask);
 187
 188                 if (newcpu >= nr_cpu_ids) {
 189                         pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
 190                                             i, cpu);
 191
 192                         cpumask_setall(mask);
 193                 }
 194                 irq_set_affinity(i, mask);
 195         }
 196 }
 197 #endif /* CONFIG_HOTPLUG_CPU */