~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/sh/kernel/irq.c

Version: ~ [ linux-5.5-rc1 ] ~ [ linux-5.4.2 ] ~ [ linux-5.3.15 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.88 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.158 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.206 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.206 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.78 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 
 24 atomic_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  */
 31 void 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  */
 41 int 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  */
 60 union irq_ctx {
 61         struct thread_info      tinfo;
 62         u32                     stack[THREAD_SIZE/sizeof(u32)];
 63 };
 64 
 65 static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
 66 static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
 67 
 68 static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
 69 static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
 70 
 71 static 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  */
119 void 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 
146 void irq_ctx_exit(int cpu)
147 {
148         hardirq_ctx[cpu] = NULL;
149 }
150 
151 void 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
179 static inline void handle_one_irq(unsigned int irq)
180 {
181         generic_handle_irq(irq);
182 }
183 #endif
184 
185 asmlinkage __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 
205 void __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  */
224 void 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
246 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp