1 /* 2 * Allwinner A20/A31 SoCs NMI IRQ chip driver. 3 * 4 * Carlo Caione <carlo.caione@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 #define DRV_NAME "sunxi-nmi" 12 #define pr_fmt(fmt) DRV_NAME ": " fmt 13 14 #include <linux/bitops.h> 15 #include <linux/device.h> 16 #include <linux/io.h> 17 #include <linux/irq.h> 18 #include <linux/interrupt.h> 19 #include <linux/irqdomain.h> 20 #include <linux/of_irq.h> 21 #include <linux/of_address.h> 22 #include <linux/of_platform.h> 23 #include <linux/irqchip.h> 24 #include <linux/irqchip/chained_irq.h> 25 26 #define SUNXI_NMI_SRC_TYPE_MASK 0x00000003 27 28 #define SUNXI_NMI_IRQ_BIT BIT(0) 29 30 #define SUN6I_R_INTC_CTRL 0x0c 31 #define SUN6I_R_INTC_PENDING 0x10 32 #define SUN6I_R_INTC_ENABLE 0x40 33 34 /* 35 * For deprecated sun6i-a31-sc-nmi compatible. 36 * Registers are offset by 0x0c. 37 */ 38 #define SUN6I_R_INTC_NMI_OFFSET 0x0c 39 #define SUN6I_NMI_CTRL (SUN6I_R_INTC_CTRL - SUN6I_R_INTC_NMI_OFFSET) 40 #define SUN6I_NMI_PENDING (SUN6I_R_INTC_PENDING - SUN6I_R_INTC_NMI_OFFSET) 41 #define SUN6I_NMI_ENABLE (SUN6I_R_INTC_ENABLE - SUN6I_R_INTC_NMI_OFFSET) 42 43 #define SUN7I_NMI_CTRL 0x00 44 #define SUN7I_NMI_PENDING 0x04 45 #define SUN7I_NMI_ENABLE 0x08 46 47 #define SUN9I_NMI_CTRL 0x00 48 #define SUN9I_NMI_ENABLE 0x04 49 #define SUN9I_NMI_PENDING 0x08 50 51 enum { 52 SUNXI_SRC_TYPE_LEVEL_LOW = 0, 53 SUNXI_SRC_TYPE_EDGE_FALLING, 54 SUNXI_SRC_TYPE_LEVEL_HIGH, 55 SUNXI_SRC_TYPE_EDGE_RISING, 56 }; 57 58 struct sunxi_sc_nmi_reg_offs { 59 u32 ctrl; 60 u32 pend; 61 u32 enable; 62 }; 63 64 static const struct sunxi_sc_nmi_reg_offs sun6i_r_intc_reg_offs __initconst = { 65 .ctrl = SUN6I_R_INTC_CTRL, 66 .pend = SUN6I_R_INTC_PENDING, 67 .enable = SUN6I_R_INTC_ENABLE, 68 }; 69 70 static const struct sunxi_sc_nmi_reg_offs sun6i_reg_offs __initconst = { 71 .ctrl = SUN6I_NMI_CTRL, 72 .pend = SUN6I_NMI_PENDING, 73 .enable = SUN6I_NMI_ENABLE, 74 }; 75 76 static const struct sunxi_sc_nmi_reg_offs sun7i_reg_offs __initconst = { 77 .ctrl = SUN7I_NMI_CTRL, 78 .pend = SUN7I_NMI_PENDING, 79 .enable = SUN7I_NMI_ENABLE, 80 }; 81 82 static const struct sunxi_sc_nmi_reg_offs sun9i_reg_offs __initconst = { 83 .ctrl = SUN9I_NMI_CTRL, 84 .pend = SUN9I_NMI_PENDING, 85 .enable = SUN9I_NMI_ENABLE, 86 }; 87 88 static inline void sunxi_sc_nmi_write(struct irq_chip_generic *gc, u32 off, 89 u32 val) 90 { 91 irq_reg_writel(gc, val, off); 92 } 93 94 static inline u32 sunxi_sc_nmi_read(struct irq_chip_generic *gc, u32 off) 95 { 96 return irq_reg_readl(gc, off); 97 } 98 99 static void sunxi_sc_nmi_handle_irq(struct irq_desc *desc) 100 { 101 struct irq_domain *domain = irq_desc_get_handler_data(desc); 102 struct irq_chip *chip = irq_desc_get_chip(desc); 103 unsigned int virq = irq_find_mapping(domain, 0); 104 105 chained_irq_enter(chip, desc); 106 generic_handle_irq(virq); 107 chained_irq_exit(chip, desc); 108 } 109 110 static int sunxi_sc_nmi_set_type(struct irq_data *data, unsigned int flow_type) 111 { 112 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); 113 struct irq_chip_type *ct = gc->chip_types; 114 u32 src_type_reg; 115 u32 ctrl_off = ct->regs.type; 116 unsigned int src_type; 117 unsigned int i; 118 119 irq_gc_lock(gc); 120 121 switch (flow_type & IRQF_TRIGGER_MASK) { 122 case IRQ_TYPE_EDGE_FALLING: 123 src_type = SUNXI_SRC_TYPE_EDGE_FALLING; 124 break; 125 case IRQ_TYPE_EDGE_RISING: 126 src_type = SUNXI_SRC_TYPE_EDGE_RISING; 127 break; 128 case IRQ_TYPE_LEVEL_HIGH: 129 src_type = SUNXI_SRC_TYPE_LEVEL_HIGH; 130 break; 131 case IRQ_TYPE_NONE: 132 case IRQ_TYPE_LEVEL_LOW: 133 src_type = SUNXI_SRC_TYPE_LEVEL_LOW; 134 break; 135 default: 136 irq_gc_unlock(gc); 137 pr_err("Cannot assign multiple trigger modes to IRQ %d.\n", 138 data->irq); 139 return -EBADR; 140 } 141 142 irqd_set_trigger_type(data, flow_type); 143 irq_setup_alt_chip(data, flow_type); 144 145 for (i = 0; i < gc->num_ct; i++, ct++) 146 if (ct->type & flow_type) 147 ctrl_off = ct->regs.type; 148 149 src_type_reg = sunxi_sc_nmi_read(gc, ctrl_off); 150 src_type_reg &= ~SUNXI_NMI_SRC_TYPE_MASK; 151 src_type_reg |= src_type; 152 sunxi_sc_nmi_write(gc, ctrl_off, src_type_reg); 153 154 irq_gc_unlock(gc); 155 156 return IRQ_SET_MASK_OK; 157 } 158 159 static int __init sunxi_sc_nmi_irq_init(struct device_node *node, 160 const struct sunxi_sc_nmi_reg_offs *reg_offs) 161 { 162 struct irq_domain *domain; 163 struct irq_chip_generic *gc; 164 unsigned int irq; 165 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; 166 int ret; 167 168 169 domain = irq_domain_add_linear(node, 1, &irq_generic_chip_ops, NULL); 170 if (!domain) { 171 pr_err("Could not register interrupt domain.\n"); 172 return -ENOMEM; 173 } 174 175 ret = irq_alloc_domain_generic_chips(domain, 1, 2, DRV_NAME, 176 handle_fasteoi_irq, clr, 0, 177 IRQ_GC_INIT_MASK_CACHE); 178 if (ret) { 179 pr_err("Could not allocate generic interrupt chip.\n"); 180 goto fail_irqd_remove; 181 } 182 183 irq = irq_of_parse_and_map(node, 0); 184 if (irq <= 0) { 185 pr_err("unable to parse irq\n"); 186 ret = -EINVAL; 187 goto fail_irqd_remove; 188 } 189 190 gc = irq_get_domain_generic_chip(domain, 0); 191 gc->reg_base = of_io_request_and_map(node, 0, of_node_full_name(node)); 192 if (IS_ERR(gc->reg_base)) { 193 pr_err("unable to map resource\n"); 194 ret = PTR_ERR(gc->reg_base); 195 goto fail_irqd_remove; 196 } 197 198 gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK; 199 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; 200 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; 201 gc->chip_types[0].chip.irq_eoi = irq_gc_ack_set_bit; 202 gc->chip_types[0].chip.irq_set_type = sunxi_sc_nmi_set_type; 203 gc->chip_types[0].chip.flags = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED; 204 gc->chip_types[0].regs.ack = reg_offs->pend; 205 gc->chip_types[0].regs.mask = reg_offs->enable; 206 gc->chip_types[0].regs.type = reg_offs->ctrl; 207 208 gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH; 209 gc->chip_types[1].chip.name = gc->chip_types[0].chip.name; 210 gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit; 211 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit; 212 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit; 213 gc->chip_types[1].chip.irq_set_type = sunxi_sc_nmi_set_type; 214 gc->chip_types[1].regs.ack = reg_offs->pend; 215 gc->chip_types[1].regs.mask = reg_offs->enable; 216 gc->chip_types[1].regs.type = reg_offs->ctrl; 217 gc->chip_types[1].handler = handle_edge_irq; 218 219 /* Disable any active interrupts */ 220 sunxi_sc_nmi_write(gc, reg_offs->enable, 0); 221 222 /* Clear any pending NMI interrupts */ 223 sunxi_sc_nmi_write(gc, reg_offs->pend, SUNXI_NMI_IRQ_BIT); 224 225 irq_set_chained_handler_and_data(irq, sunxi_sc_nmi_handle_irq, domain); 226 227 return 0; 228 229 fail_irqd_remove: 230 irq_domain_remove(domain); 231 232 return ret; 233 } 234 235 static int __init sun6i_r_intc_irq_init(struct device_node *node, 236 struct device_node *parent) 237 { 238 return sunxi_sc_nmi_irq_init(node, &sun6i_r_intc_reg_offs); 239 } 240 IRQCHIP_DECLARE(sun6i_r_intc, "allwinner,sun6i-a31-r-intc", 241 sun6i_r_intc_irq_init); 242 243 static int __init sun6i_sc_nmi_irq_init(struct device_node *node, 244 struct device_node *parent) 245 { 246 return sunxi_sc_nmi_irq_init(node, &sun6i_reg_offs); 247 } 248 IRQCHIP_DECLARE(sun6i_sc_nmi, "allwinner,sun6i-a31-sc-nmi", sun6i_sc_nmi_irq_init); 249 250 static int __init sun7i_sc_nmi_irq_init(struct device_node *node, 251 struct device_node *parent) 252 { 253 return sunxi_sc_nmi_irq_init(node, &sun7i_reg_offs); 254 } 255 IRQCHIP_DECLARE(sun7i_sc_nmi, "allwinner,sun7i-a20-sc-nmi", sun7i_sc_nmi_irq_init); 256 257 static int __init sun9i_nmi_irq_init(struct device_node *node, 258 struct device_node *parent) 259 { 260 return sunxi_sc_nmi_irq_init(node, &sun9i_reg_offs); 261 } 262 IRQCHIP_DECLARE(sun9i_nmi, "allwinner,sun9i-a80-nmi", sun9i_nmi_irq_init); 263