1 /* 2 * Abilis Systems interrupt controller driver 3 * 4 * Copyright (C) Abilis Systems 2012 5 * 6 * Author: Christian Ruppert <christian.ruppert@abilis.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include <linux/interrupt.h> 23 #include <linux/irqdomain.h> 24 #include <linux/irq.h> 25 #include <linux/irqchip.h> 26 #include <linux/of_irq.h> 27 #include <linux/of_address.h> 28 #include <linux/of_platform.h> 29 #include <linux/io.h> 30 #include <linux/slab.h> 31 #include <linux/bitops.h> 32 33 #define AB_IRQCTL_INT_ENABLE 0x00 34 #define AB_IRQCTL_INT_STATUS 0x04 35 #define AB_IRQCTL_SRC_MODE 0x08 36 #define AB_IRQCTL_SRC_POLARITY 0x0C 37 #define AB_IRQCTL_INT_MODE 0x10 38 #define AB_IRQCTL_INT_POLARITY 0x14 39 #define AB_IRQCTL_INT_FORCE 0x18 40 41 #define AB_IRQCTL_MAXIRQ 32 42 43 static inline void ab_irqctl_writereg(struct irq_chip_generic *gc, u32 reg, 44 u32 val) 45 { 46 irq_reg_writel(gc, val, reg); 47 } 48 49 static inline u32 ab_irqctl_readreg(struct irq_chip_generic *gc, u32 reg) 50 { 51 return irq_reg_readl(gc, reg); 52 } 53 54 static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type) 55 { 56 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); 57 uint32_t im, mod, pol; 58 59 im = data->mask; 60 61 irq_gc_lock(gc); 62 63 mod = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_MODE) | im; 64 pol = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_POLARITY) | im; 65 66 switch (flow_type & IRQF_TRIGGER_MASK) { 67 case IRQ_TYPE_EDGE_FALLING: 68 pol ^= im; 69 break; 70 case IRQ_TYPE_LEVEL_HIGH: 71 mod ^= im; 72 break; 73 case IRQ_TYPE_NONE: 74 flow_type = IRQ_TYPE_LEVEL_LOW; 75 case IRQ_TYPE_LEVEL_LOW: 76 mod ^= im; 77 pol ^= im; 78 break; 79 case IRQ_TYPE_EDGE_RISING: 80 break; 81 default: 82 irq_gc_unlock(gc); 83 pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n", 84 __func__, data->irq); 85 return -EBADR; 86 } 87 88 irqd_set_trigger_type(data, flow_type); 89 irq_setup_alt_chip(data, flow_type); 90 91 ab_irqctl_writereg(gc, AB_IRQCTL_SRC_MODE, mod); 92 ab_irqctl_writereg(gc, AB_IRQCTL_SRC_POLARITY, pol); 93 ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, im); 94 95 irq_gc_unlock(gc); 96 97 return IRQ_SET_MASK_OK; 98 } 99 100 static void tb10x_irq_cascade(struct irq_desc *desc) 101 { 102 struct irq_domain *domain = irq_desc_get_handler_data(desc); 103 unsigned int irq = irq_desc_get_irq(desc); 104 105 generic_handle_irq(irq_find_mapping(domain, irq)); 106 } 107 108 static int __init of_tb10x_init_irq(struct device_node *ictl, 109 struct device_node *parent) 110 { 111 int i, ret, nrirqs = of_irq_count(ictl); 112 struct resource mem; 113 struct irq_chip_generic *gc; 114 struct irq_domain *domain; 115 void __iomem *reg_base; 116 117 if (of_address_to_resource(ictl, 0, &mem)) { 118 pr_err("%s: No registers declared in DeviceTree.\n", 119 ictl->name); 120 return -EINVAL; 121 } 122 123 if (!request_mem_region(mem.start, resource_size(&mem), 124 ictl->name)) { 125 pr_err("%s: Request mem region failed.\n", ictl->name); 126 return -EBUSY; 127 } 128 129 reg_base = ioremap(mem.start, resource_size(&mem)); 130 if (!reg_base) { 131 ret = -EBUSY; 132 pr_err("%s: ioremap failed.\n", ictl->name); 133 goto ioremap_fail; 134 } 135 136 domain = irq_domain_add_linear(ictl, AB_IRQCTL_MAXIRQ, 137 &irq_generic_chip_ops, NULL); 138 if (!domain) { 139 ret = -ENOMEM; 140 pr_err("%s: Could not register interrupt domain.\n", 141 ictl->name); 142 goto irq_domain_add_fail; 143 } 144 145 ret = irq_alloc_domain_generic_chips(domain, AB_IRQCTL_MAXIRQ, 146 2, ictl->name, handle_level_irq, 147 IRQ_NOREQUEST, IRQ_NOPROBE, 148 IRQ_GC_INIT_MASK_CACHE); 149 if (ret) { 150 pr_err("%s: Could not allocate generic interrupt chip.\n", 151 ictl->name); 152 goto gc_alloc_fail; 153 } 154 155 gc = domain->gc->gc[0]; 156 gc->reg_base = reg_base; 157 158 gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK; 159 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; 160 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; 161 gc->chip_types[0].chip.irq_set_type = tb10x_irq_set_type; 162 gc->chip_types[0].regs.mask = AB_IRQCTL_INT_ENABLE; 163 164 gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH; 165 gc->chip_types[1].chip.name = gc->chip_types[0].chip.name; 166 gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit; 167 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit; 168 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit; 169 gc->chip_types[1].chip.irq_set_type = tb10x_irq_set_type; 170 gc->chip_types[1].regs.ack = AB_IRQCTL_INT_STATUS; 171 gc->chip_types[1].regs.mask = AB_IRQCTL_INT_ENABLE; 172 gc->chip_types[1].handler = handle_edge_irq; 173 174 for (i = 0; i < nrirqs; i++) { 175 unsigned int irq = irq_of_parse_and_map(ictl, i); 176 177 irq_set_chained_handler_and_data(irq, tb10x_irq_cascade, 178 domain); 179 } 180 181 ab_irqctl_writereg(gc, AB_IRQCTL_INT_ENABLE, 0); 182 ab_irqctl_writereg(gc, AB_IRQCTL_INT_MODE, 0); 183 ab_irqctl_writereg(gc, AB_IRQCTL_INT_POLARITY, 0); 184 ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, ~0UL); 185 186 return 0; 187 188 gc_alloc_fail: 189 irq_domain_remove(domain); 190 irq_domain_add_fail: 191 iounmap(reg_base); 192 ioremap_fail: 193 release_mem_region(mem.start, resource_size(&mem)); 194 return ret; 195 } 196 IRQCHIP_DECLARE(tb10x_intc, "abilis,tb10x-ictl", of_tb10x_init_irq); 197