1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright 2015-2016 Vladimir Zapolskiy <vz@mleia.com> 4 */ 5 6 #define pr_fmt(fmt) "%s: " fmt, __func__ 7 8 #include <linux/io.h> 9 #include <linux/irqchip.h> 10 #include <linux/irqchip/chained_irq.h> 11 #include <linux/of_address.h> 12 #include <linux/of_irq.h> 13 #include <linux/of_platform.h> 14 #include <linux/slab.h> 15 #include <asm/exception.h> 16 17 #define LPC32XX_INTC_MASK 0x00 18 #define LPC32XX_INTC_RAW 0x04 19 #define LPC32XX_INTC_STAT 0x08 20 #define LPC32XX_INTC_POL 0x0C 21 #define LPC32XX_INTC_TYPE 0x10 22 #define LPC32XX_INTC_FIQ 0x14 23 24 #define NR_LPC32XX_IC_IRQS 32 25 26 struct lpc32xx_irq_chip { 27 void __iomem *base; 28 struct irq_domain *domain; 29 struct irq_chip chip; 30 }; 31 32 static struct lpc32xx_irq_chip *lpc32xx_mic_irqc; 33 34 static inline u32 lpc32xx_ic_read(struct lpc32xx_irq_chip *ic, u32 reg) 35 { 36 return readl_relaxed(ic->base + reg); 37 } 38 39 static inline void lpc32xx_ic_write(struct lpc32xx_irq_chip *ic, 40 u32 reg, u32 val) 41 { 42 writel_relaxed(val, ic->base + reg); 43 } 44 45 static void lpc32xx_irq_mask(struct irq_data *d) 46 { 47 struct lpc32xx_irq_chip *ic = irq_data_get_irq_chip_data(d); 48 u32 val, mask = BIT(d->hwirq); 49 50 val = lpc32xx_ic_read(ic, LPC32XX_INTC_MASK) & ~mask; 51 lpc32xx_ic_write(ic, LPC32XX_INTC_MASK, val); 52 } 53 54 static void lpc32xx_irq_unmask(struct irq_data *d) 55 { 56 struct lpc32xx_irq_chip *ic = irq_data_get_irq_chip_data(d); 57 u32 val, mask = BIT(d->hwirq); 58 59 val = lpc32xx_ic_read(ic, LPC32XX_INTC_MASK) | mask; 60 lpc32xx_ic_write(ic, LPC32XX_INTC_MASK, val); 61 } 62 63 static void lpc32xx_irq_ack(struct irq_data *d) 64 { 65 struct lpc32xx_irq_chip *ic = irq_data_get_irq_chip_data(d); 66 u32 mask = BIT(d->hwirq); 67 68 lpc32xx_ic_write(ic, LPC32XX_INTC_RAW, mask); 69 } 70 71 static int lpc32xx_irq_set_type(struct irq_data *d, unsigned int type) 72 { 73 struct lpc32xx_irq_chip *ic = irq_data_get_irq_chip_data(d); 74 u32 val, mask = BIT(d->hwirq); 75 bool high, edge; 76 77 switch (type) { 78 case IRQ_TYPE_EDGE_RISING: 79 edge = true; 80 high = true; 81 break; 82 case IRQ_TYPE_EDGE_FALLING: 83 edge = true; 84 high = false; 85 break; 86 case IRQ_TYPE_LEVEL_HIGH: 87 edge = false; 88 high = true; 89 break; 90 case IRQ_TYPE_LEVEL_LOW: 91 edge = false; 92 high = false; 93 break; 94 default: 95 pr_info("unsupported irq type %d\n", type); 96 return -EINVAL; 97 } 98 99 irqd_set_trigger_type(d, type); 100 101 val = lpc32xx_ic_read(ic, LPC32XX_INTC_POL); 102 if (high) 103 val |= mask; 104 else 105 val &= ~mask; 106 lpc32xx_ic_write(ic, LPC32XX_INTC_POL, val); 107 108 val = lpc32xx_ic_read(ic, LPC32XX_INTC_TYPE); 109 if (edge) { 110 val |= mask; 111 irq_set_handler_locked(d, handle_edge_irq); 112 } else { 113 val &= ~mask; 114 irq_set_handler_locked(d, handle_level_irq); 115 } 116 lpc32xx_ic_write(ic, LPC32XX_INTC_TYPE, val); 117 118 return 0; 119 } 120 121 static void __exception_irq_entry lpc32xx_handle_irq(struct pt_regs *regs) 122 { 123 struct lpc32xx_irq_chip *ic = lpc32xx_mic_irqc; 124 u32 hwirq = lpc32xx_ic_read(ic, LPC32XX_INTC_STAT), irq; 125 126 while (hwirq) { 127 irq = __ffs(hwirq); 128 hwirq &= ~BIT(irq); 129 generic_handle_domain_irq(lpc32xx_mic_irqc->domain, irq); 130 } 131 } 132 133 static void lpc32xx_sic_handler(struct irq_desc *desc) 134 { 135 struct lpc32xx_irq_chip *ic = irq_desc_get_handler_data(desc); 136 struct irq_chip *chip = irq_desc_get_chip(desc); 137 u32 hwirq = lpc32xx_ic_read(ic, LPC32XX_INTC_STAT), irq; 138 139 chained_irq_enter(chip, desc); 140 141 while (hwirq) { 142 irq = __ffs(hwirq); 143 hwirq &= ~BIT(irq); 144 generic_handle_domain_irq(ic->domain, irq); 145 } 146 147 chained_irq_exit(chip, desc); 148 } 149 150 static int lpc32xx_irq_domain_map(struct irq_domain *id, unsigned int virq, 151 irq_hw_number_t hw) 152 { 153 struct lpc32xx_irq_chip *ic = id->host_data; 154 155 irq_set_chip_data(virq, ic); 156 irq_set_chip_and_handler(virq, &ic->chip, handle_level_irq); 157 irq_set_status_flags(virq, IRQ_LEVEL); 158 irq_set_noprobe(virq); 159 160 return 0; 161 } 162 163 static void lpc32xx_irq_domain_unmap(struct irq_domain *id, unsigned int virq) 164 { 165 irq_set_chip_and_handler(virq, NULL, NULL); 166 } 167 168 static const struct irq_domain_ops lpc32xx_irq_domain_ops = { 169 .map = lpc32xx_irq_domain_map, 170 .unmap = lpc32xx_irq_domain_unmap, 171 .xlate = irq_domain_xlate_twocell, 172 }; 173 174 static int __init lpc32xx_of_ic_init(struct device_node *node, 175 struct device_node *parent) 176 { 177 struct lpc32xx_irq_chip *irqc; 178 bool is_mic = of_device_is_compatible(node, "nxp,lpc3220-mic"); 179 const __be32 *reg = of_get_property(node, "reg", NULL); 180 u32 parent_irq, i, addr = reg ? be32_to_cpu(*reg) : 0; 181 182 irqc = kzalloc(sizeof(*irqc), GFP_KERNEL); 183 if (!irqc) 184 return -ENOMEM; 185 186 irqc->base = of_iomap(node, 0); 187 if (!irqc->base) { 188 pr_err("%pOF: unable to map registers\n", node); 189 kfree(irqc); 190 return -EINVAL; 191 } 192 193 irqc->chip.irq_ack = lpc32xx_irq_ack; 194 irqc->chip.irq_mask = lpc32xx_irq_mask; 195 irqc->chip.irq_unmask = lpc32xx_irq_unmask; 196 irqc->chip.irq_set_type = lpc32xx_irq_set_type; 197 if (is_mic) 198 irqc->chip.name = kasprintf(GFP_KERNEL, "%08x.mic", addr); 199 else 200 irqc->chip.name = kasprintf(GFP_KERNEL, "%08x.sic", addr); 201 202 irqc->domain = irq_domain_add_linear(node, NR_LPC32XX_IC_IRQS, 203 &lpc32xx_irq_domain_ops, irqc); 204 if (!irqc->domain) { 205 pr_err("unable to add irq domain\n"); 206 iounmap(irqc->base); 207 kfree(irqc->chip.name); 208 kfree(irqc); 209 return -ENODEV; 210 } 211 212 if (is_mic) { 213 lpc32xx_mic_irqc = irqc; 214 set_handle_irq(lpc32xx_handle_irq); 215 } else { 216 for (i = 0; i < of_irq_count(node); i++) { 217 parent_irq = irq_of_parse_and_map(node, i); 218 if (parent_irq) 219 irq_set_chained_handler_and_data(parent_irq, 220 lpc32xx_sic_handler, irqc); 221 } 222 } 223 224 lpc32xx_ic_write(irqc, LPC32XX_INTC_MASK, 0x00); 225 lpc32xx_ic_write(irqc, LPC32XX_INTC_POL, 0x00); 226 lpc32xx_ic_write(irqc, LPC32XX_INTC_TYPE, 0x00); 227 228 return 0; 229 } 230 231 IRQCHIP_DECLARE(nxp_lpc32xx_mic, "nxp,lpc3220-mic", lpc32xx_of_ic_init); 232 IRQCHIP_DECLARE(nxp_lpc32xx_sic, "nxp,lpc3220-sic", lpc32xx_of_ic_init); 233