1 /* 2 * Marvell Orion SoCs IRQ chip driver. 3 * 4 * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> 5 * 6 * This file is licensed under the terms of the GNU General Public 7 * License version 2. This program is licensed "as is" without any 8 * warranty of any kind, whether express or implied. 9 */ 10 11 #include <linux/io.h> 12 #include <linux/irq.h> 13 #include <linux/irqchip.h> 14 #include <linux/of.h> 15 #include <linux/of_address.h> 16 #include <linux/of_irq.h> 17 #include <asm/exception.h> 18 #include <asm/mach/irq.h> 19 20 /* 21 * Orion SoC main interrupt controller 22 */ 23 #define ORION_IRQS_PER_CHIP 32 24 25 #define ORION_IRQ_CAUSE 0x00 26 #define ORION_IRQ_MASK 0x04 27 #define ORION_IRQ_FIQ_MASK 0x08 28 #define ORION_IRQ_ENDP_MASK 0x0c 29 30 static struct irq_domain *orion_irq_domain; 31 32 static void 33 __exception_irq_entry orion_handle_irq(struct pt_regs *regs) 34 { 35 struct irq_domain_chip_generic *dgc = orion_irq_domain->gc; 36 int n, base = 0; 37 38 for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) { 39 struct irq_chip_generic *gc = 40 irq_get_domain_generic_chip(orion_irq_domain, base); 41 u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) & 42 gc->mask_cache; 43 while (stat) { 44 u32 hwirq = __fls(stat); 45 generic_handle_domain_irq(orion_irq_domain, 46 gc->irq_base + hwirq); 47 stat &= ~(1 << hwirq); 48 } 49 } 50 } 51 52 static int __init orion_irq_init(struct device_node *np, 53 struct device_node *parent) 54 { 55 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; 56 int n, ret, base, num_chips = 0; 57 struct resource r; 58 59 /* count number of irq chips by valid reg addresses */ 60 num_chips = of_address_count(np); 61 62 orion_irq_domain = irq_domain_add_linear(np, 63 num_chips * ORION_IRQS_PER_CHIP, 64 &irq_generic_chip_ops, NULL); 65 if (!orion_irq_domain) 66 panic("%pOFn: unable to add irq domain\n", np); 67 68 ret = irq_alloc_domain_generic_chips(orion_irq_domain, 69 ORION_IRQS_PER_CHIP, 1, np->full_name, 70 handle_level_irq, clr, 0, 71 IRQ_GC_INIT_MASK_CACHE); 72 if (ret) 73 panic("%pOFn: unable to alloc irq domain gc\n", np); 74 75 for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) { 76 struct irq_chip_generic *gc = 77 irq_get_domain_generic_chip(orion_irq_domain, base); 78 79 of_address_to_resource(np, n, &r); 80 81 if (!request_mem_region(r.start, resource_size(&r), np->name)) 82 panic("%pOFn: unable to request mem region %d", 83 np, n); 84 85 gc->reg_base = ioremap(r.start, resource_size(&r)); 86 if (!gc->reg_base) 87 panic("%pOFn: unable to map resource %d", np, n); 88 89 gc->chip_types[0].regs.mask = ORION_IRQ_MASK; 90 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; 91 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; 92 93 /* mask all interrupts */ 94 writel(0, gc->reg_base + ORION_IRQ_MASK); 95 } 96 97 set_handle_irq(orion_handle_irq); 98 return 0; 99 } 100 IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init); 101 102 /* 103 * Orion SoC bridge interrupt controller 104 */ 105 #define ORION_BRIDGE_IRQ_CAUSE 0x00 106 #define ORION_BRIDGE_IRQ_MASK 0x04 107 108 static void orion_bridge_irq_handler(struct irq_desc *desc) 109 { 110 struct irq_domain *d = irq_desc_get_handler_data(desc); 111 112 struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0); 113 u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) & 114 gc->mask_cache; 115 116 while (stat) { 117 u32 hwirq = __fls(stat); 118 119 generic_handle_domain_irq(d, gc->irq_base + hwirq); 120 stat &= ~(1 << hwirq); 121 } 122 } 123 124 /* 125 * Bridge IRQ_CAUSE is asserted regardless of IRQ_MASK register. 126 * To avoid interrupt events on stale irqs, we clear them before unmask. 127 */ 128 static unsigned int orion_bridge_irq_startup(struct irq_data *d) 129 { 130 struct irq_chip_type *ct = irq_data_get_chip_type(d); 131 132 ct->chip.irq_ack(d); 133 ct->chip.irq_unmask(d); 134 return 0; 135 } 136 137 static int __init orion_bridge_irq_init(struct device_node *np, 138 struct device_node *parent) 139 { 140 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; 141 struct resource r; 142 struct irq_domain *domain; 143 struct irq_chip_generic *gc; 144 int ret, irq, nrirqs = 32; 145 146 /* get optional number of interrupts provided */ 147 of_property_read_u32(np, "marvell,#interrupts", &nrirqs); 148 149 domain = irq_domain_add_linear(np, nrirqs, 150 &irq_generic_chip_ops, NULL); 151 if (!domain) { 152 pr_err("%pOFn: unable to add irq domain\n", np); 153 return -ENOMEM; 154 } 155 156 ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name, 157 handle_edge_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE); 158 if (ret) { 159 pr_err("%pOFn: unable to alloc irq domain gc\n", np); 160 return ret; 161 } 162 163 ret = of_address_to_resource(np, 0, &r); 164 if (ret) { 165 pr_err("%pOFn: unable to get resource\n", np); 166 return ret; 167 } 168 169 if (!request_mem_region(r.start, resource_size(&r), np->name)) { 170 pr_err("%s: unable to request mem region\n", np->name); 171 return -ENOMEM; 172 } 173 174 /* Map the parent interrupt for the chained handler */ 175 irq = irq_of_parse_and_map(np, 0); 176 if (irq <= 0) { 177 pr_err("%pOFn: unable to parse irq\n", np); 178 return -EINVAL; 179 } 180 181 gc = irq_get_domain_generic_chip(domain, 0); 182 gc->reg_base = ioremap(r.start, resource_size(&r)); 183 if (!gc->reg_base) { 184 pr_err("%pOFn: unable to map resource\n", np); 185 return -ENOMEM; 186 } 187 188 gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE; 189 gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK; 190 gc->chip_types[0].chip.irq_startup = orion_bridge_irq_startup; 191 gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit; 192 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; 193 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; 194 195 /* mask and clear all interrupts */ 196 writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK); 197 writel(0, gc->reg_base + ORION_BRIDGE_IRQ_CAUSE); 198 199 irq_set_chained_handler_and_data(irq, orion_bridge_irq_handler, 200 domain); 201 202 return 0; 203 } 204 IRQCHIP_DECLARE(orion_bridge_intc, 205 "marvell,orion-bridge-intc", orion_bridge_irq_init); 206