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 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 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 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 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 */ 83 asmlinkage void notrace asm_nmi_enter(void) 84 { 85 nmi_enter(); 86 } 87 NOKPROBE_SYMBOL(asm_nmi_enter); 88 89 asmlinkage void notrace asm_nmi_exit(void) 90 { 91 nmi_exit(); 92 } 93 NOKPROBE_SYMBOL(asm_nmi_exit); 94