1 /* 2 * IRQ domain support for SH INTC subsystem 3 * 4 * Copyright (C) 2012 Paul Mundt 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file "COPYING" in the main directory of this archive 8 * for more details. 9 */ 10 #define pr_fmt(fmt) "intc: " fmt 11 12 #include <linux/irqdomain.h> 13 #include <linux/sh_intc.h> 14 #include <linux/export.h> 15 #include "internals.h" 16 17 /** 18 * intc_irq_domain_evt_xlate() - Generic xlate for vectored IRQs. 19 * 20 * This takes care of exception vector to hwirq translation through 21 * by way of evt2irq() translation. 22 * 23 * Note: For platforms that use a flat vector space without INTEVT this 24 * basically just mimics irq_domain_xlate_onecell() by way of a nopped 25 * out evt2irq() implementation. 26 */ 27 static int intc_evt_xlate(struct irq_domain *d, struct device_node *ctrlr, 28 const u32 *intspec, unsigned int intsize, 29 unsigned long *out_hwirq, unsigned int *out_type) 30 { 31 if (WARN_ON(intsize < 1)) 32 return -EINVAL; 33 34 *out_hwirq = evt2irq(intspec[0]); 35 *out_type = IRQ_TYPE_NONE; 36 37 return 0; 38 } 39 40 static const struct irq_domain_ops intc_evt_ops = { 41 .xlate = intc_evt_xlate, 42 }; 43 44 void __init intc_irq_domain_init(struct intc_desc_int *d, 45 struct intc_hw_desc *hw) 46 { 47 unsigned int irq_base, irq_end; 48 49 /* 50 * Quick linear revmap check 51 */ 52 irq_base = evt2irq(hw->vectors[0].vect); 53 irq_end = evt2irq(hw->vectors[hw->nr_vectors - 1].vect); 54 55 /* 56 * Linear domains have a hard-wired assertion that IRQs start at 57 * 0 in order to make some performance optimizations. Lamely 58 * restrict the linear case to these conditions here, taking the 59 * tree penalty for linear cases with non-zero hwirq bases. 60 */ 61 if (irq_base == 0 && irq_end == (irq_base + hw->nr_vectors - 1)) 62 d->domain = irq_domain_add_linear(NULL, hw->nr_vectors, 63 &intc_evt_ops, NULL); 64 else 65 d->domain = irq_domain_add_tree(NULL, &intc_evt_ops, NULL); 66 67 BUG_ON(!d->domain); 68 } 69