kernel 里面的中断代码分析

More documents

Recommendations

Info

if (irq >= NR_IRQS) return -EINVAL; if (desc->chip == &no_irq_chip) //这里很很关键 /* return -ENOSYS; //功能没有实现 * Some drivers like serial.c use request_irq() heavily, * so we have to be careful not to interfere with a * running system. */ if (new->flags & IRQF_SAMPLE_RANDOM) { } /* /* * This function might sleep, we want to call it first, * outside of the atomic block. * Yes, this might clear the entropy pool if the wrong * driver is attempted to be loaded, without actually * installing a new handler, but is this really a problem, * only the sysadmin is able to do this. */ rand_initialize_irq(irq); * The following block of code has to be executed atomically */ spin_lock_irqsave(&desc->lock, flags); // ---------------------------------------------------------------------------------------------------- p = &desc->action; old = *p; if (old) { /* * Can't share interrupts unless both agree to and are * the same type (level, edge, polarity). So both flag * fields must have IRQF_SHARED set and the bits which * set the trigger type must match. */ if (!((old->flags & new->flags) & IRQF_SHARED) || ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) goto mismatch;
#if defined(CONFIG_IRQ_PER_CPU) #endif } /* All handlers must agree on per-cpuness */ if ((old->flags & IRQF_PERCPU) != (new->flags & IRQF_PERCPU)) goto mismatch; /* add new interrupt at end of irq queue */ do { p = &old->next; old = *p; } while (old); shared = 1; //----------------------------------------------------------------------------------------------------------------------- *p = new; #if defined(CONFIG_IRQ_PER_CPU) #endif if (new->flags & IRQF_PERCPU) desc->status |= IRQ_PER_CPU; //这边还得设置 chip 级别的设置,看来我们在 porting <strong>kernel</strong> 的时候,可能还要加这些函数 if (!shared) { irq_chip_set_defaults(desc->chip); /* Setup the type (level, edge polarity) if configured: */ if (new->flags & IRQF_TRIGGER_MASK) { if (desc->chip && desc->chip->set_type) else desc->chip->set_type(irq, /* new->flags & IRQF_TRIGGER_MASK); * IRQF_TRIGGER_* but the PIC does not support * multiple flow-types? */ printk(KERN_WARNING "No IRQF_TRIGGER set_type " "function for IRQ %d (%s)\n", irq,
Page 1 and 2: Index : 1.1 涉及到的代码简
Page 3 and 4: * struct irq_desc - interrupt descr
Page 5: } if (!action) return -ENOMEM; acti
Page 9 and 10: * * do_IRQ handles all hardware IRQ
Page 11 and 12: 从这表中, 我们很清楚了,
Page 13 and 14: mrs r0, cpsr eor r0, r0, #(\mode ^
Page 15 and 16: 第二部分是外部中断请求
Page 17 and 18: 可以看出, 2410a的中断控制
Page 19 and 20: 下面要重点注意的问题就
Page 21 and 22: 下面涉及的就是外部的设

kernel 里面的中断代码分析

Create successful ePaper yourself

Delete template?

Save as template?