drivers/irqchip/irq-sunxi-nmi.c

   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);