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
riscv_set_intc_hwnode_fn(struct fwnode_handle * (* fn)(void))21 void riscv_set_intc_hwnode_fn(struct fwnode_handle *(*fn)(void))
22 {
23 __get_intc_node = fn;
24 }
25
riscv_get_intc_hwnode(void)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 /**
36 * riscv_get_hart_index() - get hart index for interrupt delivery
37 * @fwnode: interrupt controller node
38 * @logical_index: index within the "interrupts-extended" property
39 * @hart_index: filled with the hart index to use
40 *
41 * RISC-V uses term "hart index" for its interrupt controllers, for the
42 * purpose of the interrupt routing to destination harts.
43 * It may be arbitrary numbers assigned to each destination hart in context
44 * of the particular interrupt domain.
45 *
46 * These numbers encoded in the optional property "riscv,hart-indexes"
47 * that should contain hart index for each interrupt destination in the same
48 * order as in the "interrupts-extended" property. If this property
49 * not exist, it assumed equal to the logical index, i.e. index within the
50 * "interrupts-extended" property.
51 *
52 * Return: error code
53 */
riscv_get_hart_index(struct fwnode_handle * fwnode,u32 logical_index,u32 * hart_index)54 int riscv_get_hart_index(struct fwnode_handle *fwnode, u32 logical_index,
55 u32 *hart_index)
56 {
57 static const char *prop_hart_index = "riscv,hart-indexes";
58 struct device_node *np = to_of_node(fwnode);
59
60 if (!np || !of_property_present(np, prop_hart_index)) {
61 *hart_index = logical_index;
62 return 0;
63 }
64
65 return of_property_read_u32_index(np, prop_hart_index,
66 logical_index, hart_index);
67 }
68
69 #ifdef CONFIG_IRQ_STACKS
70 #include <asm/irq_stack.h>
71
72 DECLARE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
73
74 #ifdef CONFIG_SHADOW_CALL_STACK
75 DEFINE_PER_CPU(ulong *, irq_shadow_call_stack_ptr);
76 #endif
77
init_irq_scs(void)78 static void init_irq_scs(void)
79 {
80 int cpu;
81
82 if (!scs_is_enabled())
83 return;
84
85 for_each_possible_cpu(cpu)
86 per_cpu(irq_shadow_call_stack_ptr, cpu) =
87 scs_alloc(cpu_to_node(cpu));
88 }
89
90 DEFINE_PER_CPU(ulong *, irq_stack_ptr);
91
92 #ifdef CONFIG_VMAP_STACK
init_irq_stacks(void)93 static void init_irq_stacks(void)
94 {
95 int cpu;
96 ulong *p;
97
98 for_each_possible_cpu(cpu) {
99 p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
100 per_cpu(irq_stack_ptr, cpu) = p;
101 }
102 }
103 #else
104 /* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
105 DEFINE_PER_CPU_ALIGNED(ulong [IRQ_STACK_SIZE/sizeof(ulong)], irq_stack);
106
init_irq_stacks(void)107 static void init_irq_stacks(void)
108 {
109 int cpu;
110
111 for_each_possible_cpu(cpu)
112 per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
113 }
114 #endif /* CONFIG_VMAP_STACK */
115
116 #ifdef CONFIG_SOFTIRQ_ON_OWN_STACK
___do_softirq(struct pt_regs * regs)117 static void ___do_softirq(struct pt_regs *regs)
118 {
119 __do_softirq();
120 }
121
do_softirq_own_stack(void)122 void do_softirq_own_stack(void)
123 {
124 if (on_thread_stack())
125 call_on_irq_stack(NULL, ___do_softirq);
126 else
127 __do_softirq();
128 }
129 #endif /* CONFIG_SOFTIRQ_ON_OWN_STACK */
130
131 #else
init_irq_scs(void)132 static void init_irq_scs(void) {}
init_irq_stacks(void)133 static void init_irq_stacks(void) {}
134 #endif /* CONFIG_IRQ_STACKS */
135
arch_show_interrupts(struct seq_file * p,int prec)136 int arch_show_interrupts(struct seq_file *p, int prec)
137 {
138 show_ipi_stats(p, prec);
139 return 0;
140 }
141
init_IRQ(void)142 void __init init_IRQ(void)
143 {
144 init_irq_scs();
145 init_irq_stacks();
146 irqchip_init();
147 if (!handle_arch_irq)
148 panic("No interrupt controller found.");
149 sbi_ipi_init();
150 }
151