1 /* 2 * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 */ 9 10 #include <linux/interrupt.h> 11 #include <linux/irqchip.h> 12 #include <asm/mach_desc.h> 13 14 /* 15 * Late Interrupt system init called from start_kernel for Boot CPU only 16 * 17 * Since slab must already be initialized, platforms can start doing any 18 * needed request_irq( )s 19 */ 20 void __init init_IRQ(void) 21 { 22 /* Any external intc can be setup here */ 23 if (machine_desc->init_irq) 24 machine_desc->init_irq(); 25 26 /* process the entire interrupt tree in one go */ 27 irqchip_init(); 28 29 #ifdef CONFIG_SMP 30 /* Master CPU can initialize it's side of IPI */ 31 if (machine_desc->init_smp) 32 machine_desc->init_smp(smp_processor_id()); 33 #endif 34 } 35 36 /* 37 * "C" Entry point for any ARC ISR, called from low level vector handler 38 * @irq is the vector number read from ICAUSE reg of on-chip intc 39 */ 40 void arch_do_IRQ(unsigned int irq, struct pt_regs *regs) 41 { 42 struct pt_regs *old_regs = set_irq_regs(regs); 43 44 irq_enter(); 45 generic_handle_irq(irq); 46 irq_exit(); 47 set_irq_regs(old_regs); 48 } 49 50 void arc_request_percpu_irq(int irq, int cpu, 51 irqreturn_t (*isr)(int irq, void *dev), 52 const char *irq_nm, 53 void *percpu_dev) 54 { 55 /* Boot cpu calls request, all call enable */ 56 if (!cpu) { 57 int rc; 58 59 /* 60 * These 2 calls are essential to making percpu IRQ APIs work 61 * Ideally these details could be hidden in irq chip map function 62 * but the issue is IPIs IRQs being static (non-DT) and platform 63 * specific, so we can't identify them there. 64 */ 65 irq_set_percpu_devid(irq); 66 irq_modify_status(irq, IRQ_NOAUTOEN, 0); /* @irq, @clr, @set */ 67 68 rc = request_percpu_irq(irq, isr, irq_nm, percpu_dev); 69 if (rc) 70 panic("Percpu IRQ request failed for %d\n", irq); 71 } 72 73 enable_percpu_irq(irq, 0); 74 } 75