arm64: dts: Revert "specify console via command line"
[linux/fpc-iii.git] / arch / sh / kernel / irq.c
blob5717c7cbdd97a4b86e0f620a1bdc2e53773c37dd
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/sh/kernel/irq.c
5 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
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>
24 atomic_t irq_err_count;
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.
31 void ack_bad_irq(unsigned int irq)
33 atomic_inc(&irq_err_count);
34 printk("unexpected IRQ trap at vector %02x\n", irq);
37 #if defined(CONFIG_PROC_FS)
39 * /proc/interrupts printing for arch specific interrupts
41 int arch_show_interrupts(struct seq_file *p, int prec)
43 int j;
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");
50 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
52 return 0;
54 #endif
56 #ifdef CONFIG_IRQSTACKS
58 * per-CPU IRQ handling contexts (thread information and stack)
60 union irq_ctx {
61 struct thread_info tinfo;
62 u32 stack[THREAD_SIZE/sizeof(u32)];
65 static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
66 static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
68 static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
69 static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
71 static inline void handle_one_irq(unsigned int irq)
73 union irq_ctx *curctx, *irqctx;
75 curctx = (union irq_ctx *)current_thread_info();
76 irqctx = hardirq_ctx[smp_processor_id()];
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)
84 if (curctx != irqctx) {
85 u32 *isp;
87 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
88 irqctx->tinfo.task = curctx->tinfo.task;
89 irqctx->tinfo.previous_sp = current_stack_pointer;
92 * Copy the softirq bits in preempt_count so that the
93 * softirq checks work in the hardirq context.
95 irqctx->tinfo.preempt_count =
96 (irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
97 (curctx->tinfo.preempt_count & SOFTIRQ_MASK);
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"
112 } else
113 generic_handle_irq(irq);
117 * allocate per-cpu stacks for hardirq and for softirq processing
119 void irq_ctx_init(int cpu)
121 union irq_ctx *irqctx;
123 if (hardirq_ctx[cpu])
124 return;
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);
132 hardirq_ctx[cpu] = irqctx;
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);
140 softirq_ctx[cpu] = irqctx;
142 printk("CPU %u irqstacks, hard=%p soft=%p\n",
143 cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
146 void irq_ctx_exit(int cpu)
148 hardirq_ctx[cpu] = NULL;
151 void do_softirq_own_stack(void)
153 struct thread_info *curctx;
154 union irq_ctx *irqctx;
155 u32 *isp;
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;
162 /* build the stack frame on the softirq stack */
163 isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
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"
178 #else
179 static inline void handle_one_irq(unsigned int irq)
181 generic_handle_irq(irq);
183 #endif
185 asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
187 struct pt_regs *old_regs = set_irq_regs(regs);
189 irq_enter();
191 irq = irq_demux(irq_lookup(irq));
193 if (irq != NO_IRQ_IGNORE) {
194 handle_one_irq(irq);
195 irq_finish(irq);
198 irq_exit();
200 set_irq_regs(old_regs);
202 return IRQ_HANDLED;
205 void __init init_IRQ(void)
207 plat_irq_setup();
209 /* Perform the machine specific initialisation */
210 if (sh_mv.mv_init_irq)
211 sh_mv.mv_init_irq();
213 intc_finalize();
215 irq_ctx_init(smp_processor_id());
218 #ifdef CONFIG_HOTPLUG_CPU
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.
224 void migrate_irqs(void)
226 unsigned int irq, cpu = smp_processor_id();
228 for_each_active_irq(irq) {
229 struct irq_data *data = irq_get_irq_data(irq);
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);
239 cpumask_setall(mask);
241 irq_set_affinity(irq, mask);
245 #endif