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 /* 31 * For deprecated sun6i-a31-sc-nmi compatible. 32 */ 33 #define SUN6I_NMI_CTRL 0x00 34 #define SUN6I_NMI_PENDING 0x04 35 #define SUN6I_NMI_ENABLE 0x34 36 37 #define SUN7I_NMI_CTRL 0x00 38 #define SUN7I_NMI_PENDING 0x04 39 #define SUN7I_NMI_ENABLE 0x08 40 41 #define SUN9I_NMI_CTRL 0x00 42 #define SUN9I_NMI_ENABLE 0x04 43 #define SUN9I_NMI_PENDING 0x08 44 45 enum { 46 SUNXI_SRC_TYPE_LEVEL_LOW = 0, 47 SUNXI_SRC_TYPE_EDGE_FALLING, 48 SUNXI_SRC_TYPE_LEVEL_HIGH, 49 SUNXI_SRC_TYPE_EDGE_RISING, 50 }; 51 52 struct sunxi_sc_nmi_reg_offs { 53 u32 ctrl; 54 u32 pend; 55 u32 enable; 56 }; 57 58 static const struct sunxi_sc_nmi_reg_offs sun6i_reg_offs __initconst = { 59 .ctrl = SUN6I_NMI_CTRL, 60 .pend = SUN6I_NMI_PENDING, 61 .enable = SUN6I_NMI_ENABLE, 62 }; 63 64 static const struct sunxi_sc_nmi_reg_offs sun7i_reg_offs __initconst = { 65 .ctrl = SUN7I_NMI_CTRL, 66 .pend = SUN7I_NMI_PENDING, 67 .enable = SUN7I_NMI_ENABLE, 68 }; 69 70 static const struct sunxi_sc_nmi_reg_offs sun9i_reg_offs __initconst = { 71 .ctrl = SUN9I_NMI_CTRL, 72 .pend = SUN9I_NMI_PENDING, 73 .enable = SUN9I_NMI_ENABLE, 74 }; 75 76 static inline void sunxi_sc_nmi_write(struct irq_chip_generic *gc, u32 off, 77 u32 val) 78 { 79 irq_reg_writel(gc, val, off); 80 } 81 82 static inline u32 sunxi_sc_nmi_read(struct irq_chip_generic *gc, u32 off) 83 { 84 return irq_reg_readl(gc, off); 85 } 86 87 static void sunxi_sc_nmi_handle_irq(struct irq_desc *desc) 88 { 89 struct irq_domain *domain = irq_desc_get_handler_data(desc); 90 struct irq_chip *chip = irq_desc_get_chip(desc); 91 92 chained_irq_enter(chip, desc); 93 generic_handle_domain_irq(domain, 0); 94 chained_irq_exit(chip, desc); 95 } 96 97 static int sunxi_sc_nmi_set_type(struct irq_data *data, unsigned int flow_type) 98 { 99 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); 100 struct irq_chip_type *ct = gc->chip_types; 101 u32 src_type_reg; 102 u32 ctrl_off = ct->regs.type; 103 unsigned int src_type; 104 unsigned int i; 105 106 irq_gc_lock(gc); 107 108 switch (flow_type & IRQF_TRIGGER_MASK) { 109 case IRQ_TYPE_EDGE_FALLING: 110 src_type = SUNXI_SRC_TYPE_EDGE_FALLING; 111 break; 112 case IRQ_TYPE_EDGE_RISING: 113 src_type = SUNXI_SRC_TYPE_EDGE_RISING; 114 break; 115 case IRQ_TYPE_LEVEL_HIGH: 116 src_type = SUNXI_SRC_TYPE_LEVEL_HIGH; 117 break; 118 case IRQ_TYPE_NONE: 119 case IRQ_TYPE_LEVEL_LOW: 120 src_type = SUNXI_SRC_TYPE_LEVEL_LOW; 121 break; 122 default: 123 irq_gc_unlock(gc); 124 pr_err("Cannot assign multiple trigger modes to IRQ %d.\n", 125 data->irq); 126 return -EBADR; 127 } 128 129 irqd_set_trigger_type(data, flow_type); 130 irq_setup_alt_chip(data, flow_type); 131 132 for (i = 0; i < gc->num_ct; i++, ct++) 133 if (ct->type & flow_type) 134 ctrl_off = ct->regs.type; 135 136 src_type_reg = sunxi_sc_nmi_read(gc, ctrl_off); 137 src_type_reg &= ~SUNXI_NMI_SRC_TYPE_MASK; 138 src_type_reg |= src_type; 139 sunxi_sc_nmi_write(gc, ctrl_off, src_type_reg); 140 141 irq_gc_unlock(gc); 142 143 return IRQ_SET_MASK_OK; 144 } 145 146 static int __init sunxi_sc_nmi_irq_init(struct device_node *node, 147 const struct sunxi_sc_nmi_reg_offs *reg_offs) 148 { 149 struct irq_domain *domain; 150 struct irq_chip_generic *gc; 151 unsigned int irq; 152 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; 153 int ret; 154 155 156 domain = irq_domain_add_linear(node, 1, &irq_generic_chip_ops, NULL); 157 if (!domain) { 158 pr_err("Could not register interrupt domain.\n"); 159 return -ENOMEM; 160 } 161 162 ret = irq_alloc_domain_generic_chips(domain, 1, 2, DRV_NAME, 163 handle_fasteoi_irq, clr, 0, 164 IRQ_GC_INIT_MASK_CACHE); 165 if (ret) { 166 pr_err("Could not allocate generic interrupt chip.\n"); 167 goto fail_irqd_remove; 168 } 169 170 irq = irq_of_parse_and_map(node, 0); 171 if (irq <= 0) { 172 pr_err("unable to parse irq\n"); 173 ret = -EINVAL; 174 goto fail_irqd_remove; 175 } 176 177 gc = irq_get_domain_generic_chip(domain, 0); 178 gc->reg_base = of_io_request_and_map(node, 0, of_node_full_name(node)); 179 if (IS_ERR(gc->reg_base)) { 180 pr_err("unable to map resource\n"); 181 ret = PTR_ERR(gc->reg_base); 182 goto fail_irqd_remove; 183 } 184 185 gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK; 186 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; 187 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; 188 gc->chip_types[0].chip.irq_eoi = irq_gc_ack_set_bit; 189 gc->chip_types[0].chip.irq_set_type = sunxi_sc_nmi_set_type; 190 gc->chip_types[0].chip.flags = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED; 191 gc->chip_types[0].regs.ack = reg_offs->pend; 192 gc->chip_types[0].regs.mask = reg_offs->enable; 193 gc->chip_types[0].regs.type = reg_offs->ctrl; 194 195 gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH; 196 gc->chip_types[1].chip.name = gc->chip_types[0].chip.name; 197 gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit; 198 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit; 199 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit; 200 gc->chip_types[1].chip.irq_set_type = sunxi_sc_nmi_set_type; 201 gc->chip_types[1].regs.ack = reg_offs->pend; 202 gc->chip_types[1].regs.mask = reg_offs->enable; 203 gc->chip_types[1].regs.type = reg_offs->ctrl; 204 gc->chip_types[1].handler = handle_edge_irq; 205 206 /* Disable any active interrupts */ 207 sunxi_sc_nmi_write(gc, reg_offs->enable, 0); 208 209 /* Clear any pending NMI interrupts */ 210 sunxi_sc_nmi_write(gc, reg_offs->pend, SUNXI_NMI_IRQ_BIT); 211 212 irq_set_chained_handler_and_data(irq, sunxi_sc_nmi_handle_irq, domain); 213 214 return 0; 215 216 fail_irqd_remove: 217 irq_domain_remove(domain); 218 219 return ret; 220 } 221 222 static int __init sun6i_sc_nmi_irq_init(struct device_node *node, 223 struct device_node *parent) 224 { 225 return sunxi_sc_nmi_irq_init(node, &sun6i_reg_offs); 226 } 227 IRQCHIP_DECLARE(sun6i_sc_nmi, "allwinner,sun6i-a31-sc-nmi", sun6i_sc_nmi_irq_init); 228 229 static int __init sun7i_sc_nmi_irq_init(struct device_node *node, 230 struct device_node *parent) 231 { 232 return sunxi_sc_nmi_irq_init(node, &sun7i_reg_offs); 233 } 234 IRQCHIP_DECLARE(sun7i_sc_nmi, "allwinner,sun7i-a20-sc-nmi", sun7i_sc_nmi_irq_init); 235 236 static int __init sun9i_nmi_irq_init(struct device_node *node, 237 struct device_node *parent) 238 { 239 return sunxi_sc_nmi_irq_init(node, &sun9i_reg_offs); 240 } 241 IRQCHIP_DECLARE(sun9i_nmi, "allwinner,sun9i-a80-nmi", sun9i_nmi_irq_init); 242