1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright 2008 Freescale Semiconductor, Inc. 4 */ 5 6 #include <linux/stddef.h> 7 #include <linux/kernel.h> 8 #include <linux/interrupt.h> 9 #include <linux/of.h> 10 #include <linux/of_irq.h> 11 12 #include <asm/mpic.h> 13 #include <asm/i8259.h> 14 15 #include "mpc86xx.h" 16 17 #ifdef CONFIG_PPC_I8259 18 static void mpc86xx_8259_cascade(struct irq_desc *desc) 19 { 20 struct irq_chip *chip = irq_desc_get_chip(desc); 21 unsigned int cascade_irq = i8259_irq(); 22 23 if (cascade_irq) 24 generic_handle_irq(cascade_irq); 25 26 chip->irq_eoi(&desc->irq_data); 27 } 28 #endif /* CONFIG_PPC_I8259 */ 29 30 void __init mpc86xx_init_irq(void) 31 { 32 #ifdef CONFIG_PPC_I8259 33 struct device_node *np; 34 struct device_node *cascade_node = NULL; 35 int cascade_irq; 36 #endif 37 38 struct mpic *mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN | 39 MPIC_SINGLE_DEST_CPU, 40 0, 256, " MPIC "); 41 BUG_ON(mpic == NULL); 42 43 mpic_init(mpic); 44 45 #ifdef CONFIG_PPC_I8259 46 /* Initialize i8259 controller */ 47 for_each_node_by_type(np, "interrupt-controller") 48 if (of_device_is_compatible(np, "chrp,iic")) { 49 cascade_node = np; 50 break; 51 } 52 53 if (cascade_node == NULL) { 54 printk(KERN_DEBUG "Could not find i8259 PIC\n"); 55 return; 56 } 57 58 cascade_irq = irq_of_parse_and_map(cascade_node, 0); 59 if (!cascade_irq) { 60 printk(KERN_ERR "Failed to map cascade interrupt\n"); 61 return; 62 } 63 64 i8259_init(cascade_node, 0); 65 of_node_put(cascade_node); 66 67 irq_set_chained_handler(cascade_irq, mpc86xx_8259_cascade); 68 #endif 69 } 70