1 /* 2 * Xtensa MX interrupt distributor 3 * 4 * Copyright (C) 2002 - 2013 Tensilica, Inc. 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 11 #include <linux/interrupt.h> 12 #include <linux/irqdomain.h> 13 #include <linux/irq.h> 14 #include <linux/irqchip.h> 15 #include <linux/of.h> 16 17 #include <asm/mxregs.h> 18 19 #define HW_IRQ_IPI_COUNT 2 20 #define HW_IRQ_MX_BASE 2 21 #define HW_IRQ_EXTERN_BASE 3 22 23 static DEFINE_PER_CPU(unsigned int, cached_irq_mask); 24 25 static int xtensa_mx_irq_map(struct irq_domain *d, unsigned int irq, 26 irq_hw_number_t hw) 27 { 28 if (hw < HW_IRQ_IPI_COUNT) { 29 struct irq_chip *irq_chip = d->host_data; 30 irq_set_chip_and_handler_name(irq, irq_chip, 31 handle_percpu_irq, "ipi"); 32 irq_set_status_flags(irq, IRQ_LEVEL); 33 return 0; 34 } 35 irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq))); 36 return xtensa_irq_map(d, irq, hw); 37 } 38 39 /* 40 * Device Tree IRQ specifier translation function which works with one or 41 * two cell bindings. First cell value maps directly to the hwirq number. 42 * Second cell if present specifies whether hwirq number is external (1) or 43 * internal (0). 44 */ 45 static int xtensa_mx_irq_domain_xlate(struct irq_domain *d, 46 struct device_node *ctrlr, 47 const u32 *intspec, unsigned int intsize, 48 unsigned long *out_hwirq, unsigned int *out_type) 49 { 50 return xtensa_irq_domain_xlate(intspec, intsize, 51 intspec[0], intspec[0] + HW_IRQ_EXTERN_BASE, 52 out_hwirq, out_type); 53 } 54 55 static const struct irq_domain_ops xtensa_mx_irq_domain_ops = { 56 .xlate = xtensa_mx_irq_domain_xlate, 57 .map = xtensa_mx_irq_map, 58 }; 59 60 void secondary_init_irq(void) 61 { 62 __this_cpu_write(cached_irq_mask, 63 XCHAL_INTTYPE_MASK_EXTERN_EDGE | 64 XCHAL_INTTYPE_MASK_EXTERN_LEVEL); 65 set_sr(XCHAL_INTTYPE_MASK_EXTERN_EDGE | 66 XCHAL_INTTYPE_MASK_EXTERN_LEVEL, intenable); 67 } 68 69 static void xtensa_mx_irq_mask(struct irq_data *d) 70 { 71 unsigned int mask = 1u << d->hwirq; 72 73 if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE | 74 XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) { 75 set_er(1u << (xtensa_get_ext_irq_no(d->hwirq) - 76 HW_IRQ_MX_BASE), MIENG); 77 } else { 78 mask = __this_cpu_read(cached_irq_mask) & ~mask; 79 __this_cpu_write(cached_irq_mask, mask); 80 set_sr(mask, intenable); 81 } 82 } 83 84 static void xtensa_mx_irq_unmask(struct irq_data *d) 85 { 86 unsigned int mask = 1u << d->hwirq; 87 88 if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE | 89 XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) { 90 set_er(1u << (xtensa_get_ext_irq_no(d->hwirq) - 91 HW_IRQ_MX_BASE), MIENGSET); 92 } else { 93 mask |= __this_cpu_read(cached_irq_mask); 94 __this_cpu_write(cached_irq_mask, mask); 95 set_sr(mask, intenable); 96 } 97 } 98 99 static void xtensa_mx_irq_enable(struct irq_data *d) 100 { 101 variant_irq_enable(d->hwirq); 102 xtensa_mx_irq_unmask(d); 103 } 104 105 static void xtensa_mx_irq_disable(struct irq_data *d) 106 { 107 xtensa_mx_irq_mask(d); 108 variant_irq_disable(d->hwirq); 109 } 110 111 static void xtensa_mx_irq_ack(struct irq_data *d) 112 { 113 set_sr(1 << d->hwirq, intclear); 114 } 115 116 static int xtensa_mx_irq_retrigger(struct irq_data *d) 117 { 118 set_sr(1 << d->hwirq, intset); 119 return 1; 120 } 121 122 static int xtensa_mx_irq_set_affinity(struct irq_data *d, 123 const struct cpumask *dest, bool force) 124 { 125 int cpu = cpumask_any_and(dest, cpu_online_mask); 126 unsigned mask = 1u << cpu; 127 128 set_er(mask, MIROUT(d->hwirq - HW_IRQ_MX_BASE)); 129 irq_data_update_effective_affinity(d, cpumask_of(cpu)); 130 131 return 0; 132 133 } 134 135 static struct irq_chip xtensa_mx_irq_chip = { 136 .name = "xtensa-mx", 137 .irq_enable = xtensa_mx_irq_enable, 138 .irq_disable = xtensa_mx_irq_disable, 139 .irq_mask = xtensa_mx_irq_mask, 140 .irq_unmask = xtensa_mx_irq_unmask, 141 .irq_ack = xtensa_mx_irq_ack, 142 .irq_retrigger = xtensa_mx_irq_retrigger, 143 .irq_set_affinity = xtensa_mx_irq_set_affinity, 144 }; 145 146 int __init xtensa_mx_init_legacy(struct device_node *interrupt_parent) 147 { 148 struct irq_domain *root_domain = 149 irq_domain_add_legacy(NULL, NR_IRQS - 1, 1, 0, 150 &xtensa_mx_irq_domain_ops, 151 &xtensa_mx_irq_chip); 152 irq_set_default_host(root_domain); 153 secondary_init_irq(); 154 return 0; 155 } 156 157 static int __init xtensa_mx_init(struct device_node *np, 158 struct device_node *interrupt_parent) 159 { 160 struct irq_domain *root_domain = 161 irq_domain_add_linear(np, NR_IRQS, &xtensa_mx_irq_domain_ops, 162 &xtensa_mx_irq_chip); 163 irq_set_default_host(root_domain); 164 secondary_init_irq(); 165 return 0; 166 } 167 IRQCHIP_DECLARE(xtensa_mx_irq_chip, "cdns,xtensa-mx", xtensa_mx_init); 168