arch/riscv/kernel/irq.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2012 Regents of the University of California
   4  * Copyright (C) 2017 SiFive
   5  * Copyright (C) 2018 Christoph Hellwig
   6  */
   7
   8 #include <linux/interrupt.h>
   9 #include <linux/irqchip.h>
  10 #include <linux/irqdomain.h>
  11 #include <linux/module.h>
  12 #include <linux/scs.h>
  13 #include <linux/seq_file.h>
  14 #include <asm/sbi.h>
  15 #include <asm/smp.h>
  16 #include <asm/softirq_stack.h>
  17 #include <asm/stacktrace.h>
  18
  19 static struct fwnode_handle *(*__get_intc_node)(void);
  20
  21 void riscv_set_intc_hwnode_fn(struct fwnode_handle *(*fn)(void))
  22 {
  23         __get_intc_node = fn;
  24 }
  25
  26 struct fwnode_handle *riscv_get_intc_hwnode(void)
  27 {
  28         if (__get_intc_node)
  29                 return __get_intc_node();
  30
  31         return NULL;
  32 }
  33 EXPORT_SYMBOL_GPL(riscv_get_intc_hwnode);
  34
  35 #ifdef CONFIG_IRQ_STACKS
  36 #include <asm/irq_stack.h>
  37
  38 DECLARE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
  39
  40 #ifdef CONFIG_SHADOW_CALL_STACK
  41 DEFINE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
  42 #endif
  43
  44 static void init_irq_scs(void)
  45 {
  46         int cpu;
  47
  48         if (!scs_is_enabled())
  49                 return;
  50
  51         for_each_possible_cpu(cpu)
  52                 per_cpu(irq_shadow_call_stack_ptr, cpu) =
  53                         scs_alloc(cpu_to_node(cpu));
  54 }
  55
  56 DEFINE_PER_CPU(ulong *, irq_stack_ptr);
  57
  58 #ifdef CONFIG_VMAP_STACK
  59 static void init_irq_stacks(void)
  60 {
  61         int cpu;
  62         ulong *p;
  63
  64         for_each_possible_cpu(cpu) {
  65                 p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
  66                 per_cpu(irq_stack_ptr, cpu) = p;
  67         }
  68 }
  69 #else
  70 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
  71 DEFINE_PER_CPU_ALIGNED(ulong [IRQ_STACK_SIZE/sizeof(ulong)], irq_stack);
  72
  73 static void init_irq_stacks(void)
  74 {
  75         int cpu;
  76
  77         for_each_possible_cpu(cpu)
  78                 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
  79 }
  80 #endif /* CONFIG_VMAP_STACK */
  81
  82 #ifdef CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK
  83 static void ___do_softirq(struct pt_regs *regs)
  84 {
  85         __do_softirq();
  86 }
  87
  88 void do_softirq_own_stack(void)
  89 {
  90         if (on_thread_stack())
  91                 call_on_irq_stack(NULL, ___do_softirq);
  92         else
  93                 __do_softirq();
  94 }
  95 #endif /* CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK */
  96
  97 #else
  98 static void init_irq_scs(void) {}
  99 static void init_irq_stacks(void) {}
 100 #endif /* CONFIG_IRQ_STACKS */
 101
 102 int arch_show_interrupts(struct seq_file *p, int prec)
 103 {
 104         show_ipi_stats(p, prec);
 105         return 0;
 106 }
 107
 108 void __init init_IRQ(void)
 109 {
 110         init_irq_scs();
 111         init_irq_stacks();
 112         irqchip_init();
 113         if (!handle_arch_irq)
 114                 panic("No interrupt controller found.");
 115         sbi_ipi_init();
 116 }