1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Based on arch/arm/kernel/irq.c
4 *
5 * Copyright (C) 1992 Linus Torvalds
6 * Modifications for ARM processor Copyright (C) 1995-2000 Russell King.
7 * Support for Dynamic Tick Timer Copyright (C) 2004-2005 Nokia Corporation.
8 * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
9 * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
10 * Copyright (C) 2012 ARM Ltd.
11 */
12
13 #include <linux/kernel_stat.h>
14 #include <linux/irq.h>
15 #include <linux/memory.h>
16 #include <linux/smp.h>
17 #include <linux/init.h>
18 #include <linux/irqchip.h>
19 #include <linux/kprobes.h>
20 #include <linux/seq_file.h>
21 #include <linux/vmalloc.h>
22 #include <asm/daifflags.h>
23 #include <asm/vmap_stack.h>
24
25 unsigned long irq_err_count;
26
27 /* Only access this in an NMI enter/exit */
28 DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts);
29
30 DEFINE_PER_CPU(unsigned long *, irq_stack_ptr);
31
arch_show_interrupts(struct seq_file * p,int prec)32 int arch_show_interrupts(struct seq_file *p, int prec)
33 {
34 show_ipi_list(p, prec);
35 seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
36 return 0;
37 }
38
39 #ifdef CONFIG_VMAP_STACK
init_irq_stacks(void)40 static void init_irq_stacks(void)
41 {
42 int cpu;
43 unsigned long *p;
44
45 for_each_possible_cpu(cpu) {
46 p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
47 per_cpu(irq_stack_ptr, cpu) = p;
48 }
49 }
50 #else
51 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
52 DEFINE_PER_CPU_ALIGNED(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack);
53
init_irq_stacks(void)54 static void init_irq_stacks(void)
55 {
56 int cpu;
57
58 for_each_possible_cpu(cpu)
59 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
60 }
61 #endif
62
init_IRQ(void)63 void __init init_IRQ(void)
64 {
65 init_irq_stacks();
66 irqchip_init();
67 if (!handle_arch_irq)
68 panic("No interrupt controller found.");
69
70 if (system_uses_irq_prio_masking()) {
71 /*
72 * Now that we have a stack for our IRQ handler, set
73 * the PMR/PSR pair to a consistent state.
74 */
75 WARN_ON(read_sysreg(daif) & PSR_A_BIT);
76 local_daif_restore(DAIF_PROCCTX_NOIRQ);
77 }
78 }
79
80 /*
81 * Stubs to make nmi_enter/exit() code callable from ASM
82 */
asm_nmi_enter(void)83 asmlinkage void notrace asm_nmi_enter(void)
84 {
85 nmi_enter();
86 }
87 NOKPROBE_SYMBOL(asm_nmi_enter);
88
asm_nmi_exit(void)89 asmlinkage void notrace asm_nmi_exit(void)
90 {
91 nmi_exit();
92 }
93 NOKPROBE_SYMBOL(asm_nmi_exit);
94
