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 #include <asm/traps.h>
  32
  33 DECLARE_PER_CPU(unsigned long, nmi_count);
  34
  35 asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
  36 {
  37 #ifdef CONFIG_DEBUG_STACKOVERFLOW
  38         /* Debugging check for stack overflow: is there less than 1KB free? */
  39         {
  40                 unsigned long sp = current_stack_pointer;
  41
  42                 sp &= THREAD_SIZE - 1;
  43
  44                 if (unlikely(sp < (sizeof(thread_info) + 1024)))
  45                         printk("Stack overflow in do_IRQ: %ld\n",
  46                                sp - sizeof(struct thread_info));
  47         }
  48 #endif
  49         generic_handle_domain_irq(NULL, hwirq);
  50 }
  51
  52 int arch_show_interrupts(struct seq_file *p, int prec)
  53 {
  54         unsigned cpu __maybe_unused;
  55 #ifdef CONFIG_SMP
  56         show_ipi_list(p, prec);
  57 #endif
  58 #if XTENSA_FAKE_NMI
  59         seq_printf(p, "%*s:", prec, "NMI");
  60         for_each_online_cpu(cpu)
  61                 seq_printf(p, " %10lu", per_cpu(nmi_count, cpu));
  62         seq_puts(p, "   Non-maskable interrupts\n");
  63 #endif
  64         return 0;
  65 }
  66
  67 int xtensa_irq_domain_xlate(const u32 *intspec, unsigned int intsize,
  68                 unsigned long int_irq, unsigned long ext_irq,
  69                 unsigned long *out_hwirq, unsigned int *out_type)
  70 {
  71         if (WARN_ON(intsize < 1 || intsize > 2))
  72                 return -EINVAL;
  73         if (intsize == 2 && intspec[1] == 1) {
  74                 int_irq = xtensa_map_ext_irq(ext_irq);
  75                 if (int_irq < XCHAL_NUM_INTERRUPTS)
  76                         *out_hwirq = int_irq;
  77                 else
  78                         return -EINVAL;
  79         } else {
  80                 *out_hwirq = int_irq;
  81         }
  82         *out_type = IRQ_TYPE_NONE;
  83         return 0;
  84 }
  85
  86 int xtensa_irq_map(struct irq_domain *d, unsigned int irq,
  87                 irq_hw_number_t hw)
  88 {
  89         struct irq_chip *irq_chip = d->host_data;
  90         u32 mask = 1 << hw;
  91
  92         if (mask & XCHAL_INTTYPE_MASK_SOFTWARE) {
  93                 irq_set_chip_and_handler_name(irq, irq_chip,
  94                                 handle_simple_irq, "level");
  95                 irq_set_status_flags(irq, IRQ_LEVEL);
  96         } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE) {
  97                 irq_set_chip_and_handler_name(irq, irq_chip,
  98                                 handle_edge_irq, "edge");
  99                 irq_clear_status_flags(irq, IRQ_LEVEL);
 100         } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL) {
 101                 irq_set_chip_and_handler_name(irq, irq_chip,
 102                                 handle_level_irq, "level");
 103                 irq_set_status_flags(irq, IRQ_LEVEL);
 104         } else if (mask & XCHAL_INTTYPE_MASK_TIMER) {
 105                 irq_set_chip_and_handler_name(irq, irq_chip,
 106                                 handle_percpu_irq, "timer");
 107                 irq_clear_status_flags(irq, IRQ_LEVEL);
 108 #ifdef XCHAL_INTTYPE_MASK_PROFILING
 109         } else if (mask & XCHAL_INTTYPE_MASK_PROFILING) {
 110                 irq_set_chip_and_handler_name(irq, irq_chip,
 111                                 handle_percpu_irq, "profiling");
 112                 irq_set_status_flags(irq, IRQ_LEVEL);
 113 #endif
 114         } else {/* XCHAL_INTTYPE_MASK_WRITE_ERROR */
 115                 /* XCHAL_INTTYPE_MASK_NMI */
 116                 irq_set_chip_and_handler_name(irq, irq_chip,
 117                                 handle_level_irq, "level");
 118                 irq_set_status_flags(irq, IRQ_LEVEL);
 119         }
 120         return 0;
 121 }
 122
 123 unsigned xtensa_map_ext_irq(unsigned ext_irq)
 124 {
 125         unsigned mask = XCHAL_INTTYPE_MASK_EXTERN_EDGE |
 126                 XCHAL_INTTYPE_MASK_EXTERN_LEVEL;
 127         unsigned i;
 128
 129         for (i = 0; mask; ++i, mask >>= 1) {
 130                 if ((mask & 1) && ext_irq-- == 0)
 131                         return i;
 132         }
 133         return XCHAL_NUM_INTERRUPTS;
 134 }
 135
 136 unsigned xtensa_get_ext_irq_no(unsigned irq)
 137 {
 138         unsigned mask = (XCHAL_INTTYPE_MASK_EXTERN_EDGE |
 139                 XCHAL_INTTYPE_MASK_EXTERN_LEVEL) &
 140                 ((1u << irq) - 1);
 141         return hweight32(mask);
 142 }
 143
 144 void __init init_IRQ(void)
 145 {
 146 #ifdef CONFIG_USE_OF
 147         irqchip_init();
 148 #else
 149 #ifdef CONFIG_HAVE_SMP
 150         xtensa_mx_init_legacy(NULL);
 151 #else
 152         xtensa_pic_init_legacy(NULL);
 153 #endif
 154 #endif
 155
 156 #ifdef CONFIG_SMP
 157         ipi_init();
 158 #endif
 159 }
 160
 161 #ifdef CONFIG_HOTPLUG_CPU
 162 /*
 163  * The CPU has been marked offline.  Migrate IRQs off this CPU.  If
 164  * the affinity settings do not allow other CPUs, force them onto any
 165  * available CPU.
 166  */
 167 void migrate_irqs(void)
 168 {
 169         unsigned int i, cpu = smp_processor_id();
 170
 171         for_each_active_irq(i) {
 172                 struct irq_data *data = irq_get_irq_data(i);
 173                 const struct cpumask *mask;
 174                 unsigned int newcpu;
 175
 176                 if (irqd_is_per_cpu(data))
 177                         continue;
 178
 179                 mask = irq_data_get_affinity_mask(data);
 180                 if (!cpumask_test_cpu(cpu, mask))
 181                         continue;
 182
 183                 newcpu = cpumask_any_and(mask, cpu_online_mask);
 184
 185                 if (newcpu >= nr_cpu_ids) {
 186                         pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
 187                                             i, cpu);
 188
 189                         irq_set_affinity(i, cpu_all_mask);
 190                 } else {
 191                         irq_set_affinity(i, mask);
 192                 }
 193         }
 194 }
 195 #endif /* CONFIG_HOTPLUG_CPU */