1 /* 2 * Copyright 2008 Freescale Semiconductor, Inc. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License as published by the 6 * Free Software Foundation; either version 2 of the License, or (at your 7 * option) any later version. 8 */ 9 10 #include <linux/stddef.h> 11 #include <linux/kernel.h> 12 #include <linux/interrupt.h> 13 #include <linux/of_platform.h> 14 15 #include <asm/system.h> 16 #include <asm/mpic.h> 17 #include <asm/i8259.h> 18 19 #ifdef CONFIG_PPC_I8259 20 static void mpc86xx_8259_cascade(unsigned int irq, struct irq_desc *desc) 21 { 22 struct irq_chip *chip = irq_desc_get_chip(desc); 23 unsigned int cascade_irq = i8259_irq(); 24 25 if (cascade_irq != NO_IRQ) 26 generic_handle_irq(cascade_irq); 27 28 chip->irq_eoi(&desc->irq_data); 29 } 30 #endif /* CONFIG_PPC_I8259 */ 31 32 void __init mpc86xx_init_irq(void) 33 { 34 #ifdef CONFIG_PPC_I8259 35 struct device_node *np; 36 struct device_node *cascade_node = NULL; 37 int cascade_irq; 38 #endif 39 40 struct mpic *mpic = mpic_alloc(NULL, 0, 41 MPIC_WANTS_RESET | MPIC_BIG_ENDIAN | 42 MPIC_BROKEN_FRR_NIRQS | MPIC_SINGLE_DEST_CPU, 43 0, 256, " MPIC "); 44 BUG_ON(mpic == NULL); 45 46 mpic_init(mpic); 47 48 #ifdef CONFIG_PPC_I8259 49 /* Initialize i8259 controller */ 50 for_each_node_by_type(np, "interrupt-controller") 51 if (of_device_is_compatible(np, "chrp,iic")) { 52 cascade_node = np; 53 break; 54 } 55 56 if (cascade_node == NULL) { 57 printk(KERN_DEBUG "Could not find i8259 PIC\n"); 58 return; 59 } 60 61 cascade_irq = irq_of_parse_and_map(cascade_node, 0); 62 if (cascade_irq == NO_IRQ) { 63 printk(KERN_ERR "Failed to map cascade interrupt\n"); 64 return; 65 } 66 67 i8259_init(cascade_node, 0); 68 of_node_put(cascade_node); 69 70 irq_set_chained_handler(cascade_irq, mpc86xx_8259_cascade); 71 #endif 72 } 73