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1/*
2 * linux/arch/sh/kernel/irq.c
3 *
4 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
5 *
6 *
7 * SuperH version: Copyright (C) 1999 Niibe Yutaka
8 */
9#include <linux/irq.h>
10#include <linux/interrupt.h>
11#include <linux/module.h>
12#include <linux/kernel_stat.h>
13#include <linux/seq_file.h>
14#include <linux/ftrace.h>
15#include <linux/delay.h>
16#include <linux/ratelimit.h>
17#include <asm/processor.h>
18#include <asm/machvec.h>
19#include <asm/uaccess.h>
20#include <asm/thread_info.h>
21#include <cpu/mmu_context.h>
22
23atomic_t irq_err_count;
24
25/*
26 * 'what should we do if we get a hw irq event on an illegal vector'.
27 * each architecture has to answer this themselves, it doesn't deserve
28 * a generic callback i think.
29 */
30void ack_bad_irq(unsigned int irq)
31{
32 atomic_inc(&irq_err_count);
33 printk("unexpected IRQ trap at vector %02x\n", irq);
34}
35
36#if defined(CONFIG_PROC_FS)
37/*
38 * /proc/interrupts printing for arch specific interrupts
39 */
40int arch_show_interrupts(struct seq_file *p, int prec)
41{
42 int j;
43
44 seq_printf(p, "%*s: ", prec, "NMI");
45 for_each_online_cpu(j)
46 seq_printf(p, "%10u ", irq_stat[j].__nmi_count);
47 seq_printf(p, " Non-maskable interrupts\n");
48
49 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
50
51 return 0;
52}
53#endif
54
55#ifdef CONFIG_IRQSTACKS
56/*
57 * per-CPU IRQ handling contexts (thread information and stack)
58 */
59union irq_ctx {
60 struct thread_info tinfo;
61 u32 stack[THREAD_SIZE/sizeof(u32)];
62};
63
64static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
65static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
66
67static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
68static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
69
70static inline void handle_one_irq(unsigned int irq)
71{
72 union irq_ctx *curctx, *irqctx;
73
74 curctx = (union irq_ctx *)current_thread_info();
75 irqctx = hardirq_ctx[smp_processor_id()];
76
77 /*
78 * this is where we switch to the IRQ stack. However, if we are
79 * already using the IRQ stack (because we interrupted a hardirq
80 * handler) we can't do that and just have to keep using the
81 * current stack (which is the irq stack already after all)
82 */
83 if (curctx != irqctx) {
84 u32 *isp;
85
86 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
87 irqctx->tinfo.task = curctx->tinfo.task;
88 irqctx->tinfo.previous_sp = current_stack_pointer;
89
90 /*
91 * Copy the softirq bits in preempt_count so that the
92 * softirq checks work in the hardirq context.
93 */
94 irqctx->tinfo.preempt_count =
95 (irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
96 (curctx->tinfo.preempt_count & SOFTIRQ_MASK);
97
98 __asm__ __volatile__ (
99 "mov %0, r4 \n"
100 "mov r15, r8 \n"
101 "jsr @%1 \n"
102 /* swith to the irq stack */
103 " mov %2, r15 \n"
104 /* restore the stack (ring zero) */
105 "mov r8, r15 \n"
106 : /* no outputs */
107 : "r" (irq), "r" (generic_handle_irq), "r" (isp)
108 : "memory", "r0", "r1", "r2", "r3", "r4",
109 "r5", "r6", "r7", "r8", "t", "pr"
110 );
111 } else
112 generic_handle_irq(irq);
113}
114
115/*
116 * allocate per-cpu stacks for hardirq and for softirq processing
117 */
118void irq_ctx_init(int cpu)
119{
120 union irq_ctx *irqctx;
121
122 if (hardirq_ctx[cpu])
123 return;
124
125 irqctx = (union irq_ctx *)&hardirq_stack[cpu * THREAD_SIZE];
126 irqctx->tinfo.task = NULL;
127 irqctx->tinfo.cpu = cpu;
128 irqctx->tinfo.preempt_count = HARDIRQ_OFFSET;
129 irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
130
131 hardirq_ctx[cpu] = irqctx;
132
133 irqctx = (union irq_ctx *)&softirq_stack[cpu * THREAD_SIZE];
134 irqctx->tinfo.task = NULL;
135 irqctx->tinfo.cpu = cpu;
136 irqctx->tinfo.preempt_count = 0;
137 irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
138
139 softirq_ctx[cpu] = irqctx;
140
141 printk("CPU %u irqstacks, hard=%p soft=%p\n",
142 cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
143}
144
145void irq_ctx_exit(int cpu)
146{
147 hardirq_ctx[cpu] = NULL;
148}
149
150void do_softirq_own_stack(void)
151{
152 struct thread_info *curctx;
153 union irq_ctx *irqctx;
154 u32 *isp;
155
156 curctx = current_thread_info();
157 irqctx = softirq_ctx[smp_processor_id()];
158 irqctx->tinfo.task = curctx->task;
159 irqctx->tinfo.previous_sp = current_stack_pointer;
160
161 /* build the stack frame on the softirq stack */
162 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
163
164 __asm__ __volatile__ (
165 "mov r15, r9 \n"
166 "jsr @%0 \n"
167 /* switch to the softirq stack */
168 " mov %1, r15 \n"
169 /* restore the thread stack */
170 "mov r9, r15 \n"
171 : /* no outputs */
172 : "r" (__do_softirq), "r" (isp)
173 : "memory", "r0", "r1", "r2", "r3", "r4",
174 "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
175 );
176}
177#else
178static inline void handle_one_irq(unsigned int irq)
179{
180 generic_handle_irq(irq);
181}
182#endif
183
184asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
185{
186 struct pt_regs *old_regs = set_irq_regs(regs);
187
188 irq_enter();
189
190 irq = irq_demux(irq_lookup(irq));
191
192 if (irq != NO_IRQ_IGNORE) {
193 handle_one_irq(irq);
194 irq_finish(irq);
195 }
196
197 irq_exit();
198
199 set_irq_regs(old_regs);
200
201 return IRQ_HANDLED;
202}
203
204void __init init_IRQ(void)
205{
206 plat_irq_setup();
207
208 /* Perform the machine specific initialisation */
209 if (sh_mv.mv_init_irq)
210 sh_mv.mv_init_irq();
211
212 intc_finalize();
213
214 irq_ctx_init(smp_processor_id());
215}
216
217#ifdef CONFIG_HOTPLUG_CPU
218/*
219 * The CPU has been marked offline. Migrate IRQs off this CPU. If
220 * the affinity settings do not allow other CPUs, force them onto any
221 * available CPU.
222 */
223void migrate_irqs(void)
224{
225 unsigned int irq, cpu = smp_processor_id();
226
227 for_each_active_irq(irq) {
228 struct irq_data *data = irq_get_irq_data(irq);
229
230 if (irq_data_get_node(data) == cpu) {
231 struct cpumask *mask = irq_data_get_affinity_mask(data);
232 unsigned int newcpu = cpumask_any_and(mask,
233 cpu_online_mask);
234 if (newcpu >= nr_cpu_ids) {
235 pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
236 irq, cpu);
237
238 cpumask_setall(mask);
239 }
240 irq_set_affinity(irq, mask);
241 }
242 }
243}
244#endif
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/sh/kernel/irq.c
4 *
5 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
6 *
7 *
8 * SuperH version: Copyright (C) 1999 Niibe Yutaka
9 */
10#include <linux/irq.h>
11#include <linux/interrupt.h>
12#include <linux/module.h>
13#include <linux/kernel_stat.h>
14#include <linux/seq_file.h>
15#include <linux/ftrace.h>
16#include <linux/delay.h>
17#include <linux/ratelimit.h>
18#include <asm/processor.h>
19#include <asm/machvec.h>
20#include <linux/uaccess.h>
21#include <asm/thread_info.h>
22#include <cpu/mmu_context.h>
23
24atomic_t irq_err_count;
25
26/*
27 * 'what should we do if we get a hw irq event on an illegal vector'.
28 * each architecture has to answer this themselves, it doesn't deserve
29 * a generic callback i think.
30 */
31void ack_bad_irq(unsigned int irq)
32{
33 atomic_inc(&irq_err_count);
34 printk("unexpected IRQ trap at vector %02x\n", irq);
35}
36
37#if defined(CONFIG_PROC_FS)
38/*
39 * /proc/interrupts printing for arch specific interrupts
40 */
41int arch_show_interrupts(struct seq_file *p, int prec)
42{
43 int j;
44
45 seq_printf(p, "%*s: ", prec, "NMI");
46 for_each_online_cpu(j)
47 seq_printf(p, "%10u ", nmi_count(j));
48 seq_printf(p, " Non-maskable interrupts\n");
49
50 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
51
52 return 0;
53}
54#endif
55
56#ifdef CONFIG_IRQSTACKS
57/*
58 * per-CPU IRQ handling contexts (thread information and stack)
59 */
60union irq_ctx {
61 struct thread_info tinfo;
62 u32 stack[THREAD_SIZE/sizeof(u32)];
63};
64
65static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
66static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
67
68static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
69static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
70
71static inline void handle_one_irq(unsigned int irq)
72{
73 union irq_ctx *curctx, *irqctx;
74
75 curctx = (union irq_ctx *)current_thread_info();
76 irqctx = hardirq_ctx[smp_processor_id()];
77
78 /*
79 * this is where we switch to the IRQ stack. However, if we are
80 * already using the IRQ stack (because we interrupted a hardirq
81 * handler) we can't do that and just have to keep using the
82 * current stack (which is the irq stack already after all)
83 */
84 if (curctx != irqctx) {
85 u32 *isp;
86
87 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
88 irqctx->tinfo.task = curctx->tinfo.task;
89 irqctx->tinfo.previous_sp = current_stack_pointer;
90
91 /*
92 * Copy the softirq bits in preempt_count so that the
93 * softirq checks work in the hardirq context.
94 */
95 irqctx->tinfo.preempt_count =
96 (irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
97 (curctx->tinfo.preempt_count & SOFTIRQ_MASK);
98
99 __asm__ __volatile__ (
100 "mov %0, r4 \n"
101 "mov r15, r8 \n"
102 "jsr @%1 \n"
103 /* switch to the irq stack */
104 " mov %2, r15 \n"
105 /* restore the stack (ring zero) */
106 "mov r8, r15 \n"
107 : /* no outputs */
108 : "r" (irq), "r" (generic_handle_irq), "r" (isp)
109 : "memory", "r0", "r1", "r2", "r3", "r4",
110 "r5", "r6", "r7", "r8", "t", "pr"
111 );
112 } else
113 generic_handle_irq(irq);
114}
115
116/*
117 * allocate per-cpu stacks for hardirq and for softirq processing
118 */
119void irq_ctx_init(int cpu)
120{
121 union irq_ctx *irqctx;
122
123 if (hardirq_ctx[cpu])
124 return;
125
126 irqctx = (union irq_ctx *)&hardirq_stack[cpu * THREAD_SIZE];
127 irqctx->tinfo.task = NULL;
128 irqctx->tinfo.cpu = cpu;
129 irqctx->tinfo.preempt_count = HARDIRQ_OFFSET;
130 irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
131
132 hardirq_ctx[cpu] = irqctx;
133
134 irqctx = (union irq_ctx *)&softirq_stack[cpu * THREAD_SIZE];
135 irqctx->tinfo.task = NULL;
136 irqctx->tinfo.cpu = cpu;
137 irqctx->tinfo.preempt_count = 0;
138 irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
139
140 softirq_ctx[cpu] = irqctx;
141
142 printk("CPU %u irqstacks, hard=%p soft=%p\n",
143 cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
144}
145
146void irq_ctx_exit(int cpu)
147{
148 hardirq_ctx[cpu] = NULL;
149}
150
151void do_softirq_own_stack(void)
152{
153 struct thread_info *curctx;
154 union irq_ctx *irqctx;
155 u32 *isp;
156
157 curctx = current_thread_info();
158 irqctx = softirq_ctx[smp_processor_id()];
159 irqctx->tinfo.task = curctx->task;
160 irqctx->tinfo.previous_sp = current_stack_pointer;
161
162 /* build the stack frame on the softirq stack */
163 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
164
165 __asm__ __volatile__ (
166 "mov r15, r9 \n"
167 "jsr @%0 \n"
168 /* switch to the softirq stack */
169 " mov %1, r15 \n"
170 /* restore the thread stack */
171 "mov r9, r15 \n"
172 : /* no outputs */
173 : "r" (__do_softirq), "r" (isp)
174 : "memory", "r0", "r1", "r2", "r3", "r4",
175 "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
176 );
177}
178#else
179static inline void handle_one_irq(unsigned int irq)
180{
181 generic_handle_irq(irq);
182}
183#endif
184
185asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
186{
187 struct pt_regs *old_regs = set_irq_regs(regs);
188
189 irq_enter();
190
191 irq = irq_demux(irq_lookup(irq));
192
193 if (irq != NO_IRQ_IGNORE) {
194 handle_one_irq(irq);
195 irq_finish(irq);
196 }
197
198 irq_exit();
199
200 set_irq_regs(old_regs);
201
202 return IRQ_HANDLED;
203}
204
205void __init init_IRQ(void)
206{
207 plat_irq_setup();
208
209 /* Perform the machine specific initialisation */
210 if (sh_mv.mv_init_irq)
211 sh_mv.mv_init_irq();
212
213 intc_finalize();
214
215 irq_ctx_init(smp_processor_id());
216}
217
218#ifdef CONFIG_HOTPLUG_CPU
219/*
220 * The CPU has been marked offline. Migrate IRQs off this CPU. If
221 * the affinity settings do not allow other CPUs, force them onto any
222 * available CPU.
223 */
224void migrate_irqs(void)
225{
226 unsigned int irq, cpu = smp_processor_id();
227
228 for_each_active_irq(irq) {
229 struct irq_data *data = irq_get_irq_data(irq);
230
231 if (irq_data_get_node(data) == cpu) {
232 struct cpumask *mask = irq_data_get_affinity_mask(data);
233 unsigned int newcpu = cpumask_any_and(mask,
234 cpu_online_mask);
235 if (newcpu >= nr_cpu_ids) {
236 pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
237 irq, cpu);
238
239 cpumask_setall(mask);
240 }
241 irq_set_affinity(irq, mask);
242 }
243 }
244}
245#endif