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
19static struct fwnode_handle *(*__get_intc_node)(void);
20
21void riscv_set_intc_hwnode_fn(struct fwnode_handle *(*fn)(void))
22{
23 __get_intc_node = fn;
24}
25
26struct fwnode_handle *riscv_get_intc_hwnode(void)
27{
28 if (__get_intc_node)
29 return __get_intc_node();
30
31 return NULL;
32}
33EXPORT_SYMBOL_GPL(riscv_get_intc_hwnode);
34
35#ifdef CONFIG_IRQ_STACKS
36#include <asm/irq_stack.h>
37
38DECLARE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
39
40#ifdef CONFIG_SHADOW_CALL_STACK
41DEFINE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
42#endif
43
44static 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
56DEFINE_PER_CPU(ulong *, irq_stack_ptr);
57
58#ifdef CONFIG_VMAP_STACK
59static 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. */
71DEFINE_PER_CPU_ALIGNED(ulong [IRQ_STACK_SIZE/sizeof(ulong)], irq_stack);
72
73static 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_SOFTIRQ_ON_OWN_STACK
83static void ___do_softirq(struct pt_regs *regs)
84{
85 __do_softirq();
86}
87
88void 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_SOFTIRQ_ON_OWN_STACK */
96
97#else
98static void init_irq_scs(void) {}
99static void init_irq_stacks(void) {}
100#endif /* CONFIG_IRQ_STACKS */
101
102int arch_show_interrupts(struct seq_file *p, int prec)
103{
104 show_ipi_stats(p, prec);
105 return 0;
106}
107
108void __init init_IRQ(void)
109{
110 init_irq_scs();
111 init_irq_stacks();
112 irqchip_init();
113 if (!handle_arch_irq)
114 panic(fmt: "No interrupt controller found.");
115 sbi_ipi_init();
116}
117

source code of linux/arch/riscv/kernel/irq.c