drivers/irqchip/irq-clps711x.c

   1 /*
   2  *  CLPS711X IRQ driver
   3  *
   4  *  Copyright (C) 2013 Alexander Shiyan <shc_work@mail.ru>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/io.h>
  13 #include <linux/irq.h>
  14 #include <linux/irqchip.h>
  15 #include <linux/irqdomain.h>
  16 #include <linux/of_address.h>
  17 #include <linux/of_irq.h>
  18 #include <linux/slab.h>
  19
  20 #include <asm/exception.h>
  21 #include <asm/mach/irq.h>
  22
  23 #define CLPS711X_INTSR1 (0x0240)
  24 #define CLPS711X_INTMR1 (0x0280)
  25 #define CLPS711X_BLEOI  (0x0600)
  26 #define CLPS711X_MCEOI  (0x0640)
  27 #define CLPS711X_TEOI   (0x0680)
  28 #define CLPS711X_TC1EOI (0x06c0)
  29 #define CLPS711X_TC2EOI (0x0700)
  30 #define CLPS711X_RTCEOI (0x0740)
  31 #define CLPS711X_UMSEOI (0x0780)
  32 #define CLPS711X_COEOI  (0x07c0)
  33 #define CLPS711X_INTSR2 (0x1240)
  34 #define CLPS711X_INTMR2 (0x1280)
  35 #define CLPS711X_SRXEOF (0x1600)
  36 #define CLPS711X_KBDEOI (0x1700)
  37 #define CLPS711X_INTSR3 (0x2240)
  38 #define CLPS711X_INTMR3 (0x2280)
  39
  40 static const struct {
  41 #define CLPS711X_FLAG_EN        (1 << 0)
  42 #define CLPS711X_FLAG_FIQ       (1 << 1)
  43         unsigned int    flags;
  44         phys_addr_t     eoi;
  45 } clps711x_irqs[] = {
  46         [1]     = { CLPS711X_FLAG_FIQ, CLPS711X_BLEOI, },
  47         [3]     = { CLPS711X_FLAG_FIQ, CLPS711X_MCEOI, },
  48         [4]     = { CLPS711X_FLAG_EN, CLPS711X_COEOI, },
  49         [5]     = { CLPS711X_FLAG_EN, },
  50         [6]     = { CLPS711X_FLAG_EN, },
  51         [7]     = { CLPS711X_FLAG_EN, },
  52         [8]     = { CLPS711X_FLAG_EN, CLPS711X_TC1EOI, },
  53         [9]     = { CLPS711X_FLAG_EN, CLPS711X_TC2EOI, },
  54         [10]    = { CLPS711X_FLAG_EN, CLPS711X_RTCEOI, },
  55         [11]    = { CLPS711X_FLAG_EN, CLPS711X_TEOI, },
  56         [12]    = { CLPS711X_FLAG_EN, },
  57         [13]    = { CLPS711X_FLAG_EN, },
  58         [14]    = { CLPS711X_FLAG_EN, CLPS711X_UMSEOI, },
  59         [15]    = { CLPS711X_FLAG_EN, CLPS711X_SRXEOF, },
  60         [16]    = { CLPS711X_FLAG_EN, CLPS711X_KBDEOI, },
  61         [17]    = { CLPS711X_FLAG_EN, },
  62         [18]    = { CLPS711X_FLAG_EN, },
  63         [28]    = { CLPS711X_FLAG_EN, },
  64         [29]    = { CLPS711X_FLAG_EN, },
  65         [32]    = { CLPS711X_FLAG_FIQ, },
  66 };
  67
  68 static struct {
  69         void __iomem            *base;
  70         void __iomem            *intmr[3];
  71         void __iomem            *intsr[3];
  72         struct irq_domain       *domain;
  73         struct irq_domain_ops   ops;
  74 } *clps711x_intc;
  75
  76 static asmlinkage void __exception_irq_entry clps711x_irqh(struct pt_regs *regs)
  77 {
  78         u32 irqstat;
  79
  80         do {
  81                 irqstat = readw_relaxed(clps711x_intc->intmr[0]) &
  82                           readw_relaxed(clps711x_intc->intsr[0]);
  83                 if (irqstat)
  84                         handle_domain_irq(clps711x_intc->domain,
  85                                           fls(irqstat) - 1, regs);
  86
  87                 irqstat = readw_relaxed(clps711x_intc->intmr[1]) &
  88                           readw_relaxed(clps711x_intc->intsr[1]);
  89                 if (irqstat)
  90                         handle_domain_irq(clps711x_intc->domain,
  91                                           fls(irqstat) - 1 + 16, regs);
  92         } while (irqstat);
  93 }
  94
  95 static void clps711x_intc_eoi(struct irq_data *d)
  96 {
  97         irq_hw_number_t hwirq = irqd_to_hwirq(d);
  98
  99         writel_relaxed(0, clps711x_intc->base + clps711x_irqs[hwirq].eoi);
 100 }
 101
 102 static void clps711x_intc_mask(struct irq_data *d)
 103 {
 104         irq_hw_number_t hwirq = irqd_to_hwirq(d);
 105         void __iomem *intmr = clps711x_intc->intmr[hwirq / 16];
 106         u32 tmp;
 107
 108         tmp = readl_relaxed(intmr);
 109         tmp &= ~(1 << (hwirq % 16));
 110         writel_relaxed(tmp, intmr);
 111 }
 112
 113 static void clps711x_intc_unmask(struct irq_data *d)
 114 {
 115         irq_hw_number_t hwirq = irqd_to_hwirq(d);
 116         void __iomem *intmr = clps711x_intc->intmr[hwirq / 16];
 117         u32 tmp;
 118
 119         tmp = readl_relaxed(intmr);
 120         tmp |= 1 << (hwirq % 16);
 121         writel_relaxed(tmp, intmr);
 122 }
 123
 124 static struct irq_chip clps711x_intc_chip = {
 125         .name           = "clps711x-intc",
 126         .irq_eoi        = clps711x_intc_eoi,
 127         .irq_mask       = clps711x_intc_mask,
 128         .irq_unmask     = clps711x_intc_unmask,
 129 };
 130
 131 static int __init clps711x_intc_irq_map(struct irq_domain *h, unsigned int virq,
 132                                         irq_hw_number_t hw)
 133 {
 134         irq_flow_handler_t handler = handle_level_irq;
 135         unsigned int flags = 0;
 136
 137         if (!clps711x_irqs[hw].flags)
 138                 return 0;
 139
 140         if (clps711x_irqs[hw].flags & CLPS711X_FLAG_FIQ) {
 141                 handler = handle_bad_irq;
 142                 flags |= IRQ_NOAUTOEN;
 143         } else if (clps711x_irqs[hw].eoi) {
 144                 handler = handle_fasteoi_irq;
 145         }
 146
 147         /* Clear down pending interrupt */
 148         if (clps711x_irqs[hw].eoi)
 149                 writel_relaxed(0, clps711x_intc->base + clps711x_irqs[hw].eoi);
 150
 151         irq_set_chip_and_handler(virq, &clps711x_intc_chip, handler);
 152         irq_modify_status(virq, IRQ_NOPROBE, flags);
 153
 154         return 0;
 155 }
 156
 157 static int __init _clps711x_intc_init(struct device_node *np,
 158                                       phys_addr_t base, resource_size_t size)
 159 {
 160         int err;
 161
 162         clps711x_intc = kzalloc(sizeof(*clps711x_intc), GFP_KERNEL);
 163         if (!clps711x_intc)
 164                 return -ENOMEM;
 165
 166         clps711x_intc->base = ioremap(base, size);
 167         if (!clps711x_intc->base) {
 168                 err = -ENOMEM;
 169                 goto out_kfree;
 170         }
 171
 172         clps711x_intc->intsr[0] = clps711x_intc->base + CLPS711X_INTSR1;
 173         clps711x_intc->intmr[0] = clps711x_intc->base + CLPS711X_INTMR1;
 174         clps711x_intc->intsr[1] = clps711x_intc->base + CLPS711X_INTSR2;
 175         clps711x_intc->intmr[1] = clps711x_intc->base + CLPS711X_INTMR2;
 176         clps711x_intc->intsr[2] = clps711x_intc->base + CLPS711X_INTSR3;
 177         clps711x_intc->intmr[2] = clps711x_intc->base + CLPS711X_INTMR3;
 178
 179         /* Mask all interrupts */
 180         writel_relaxed(0, clps711x_intc->intmr[0]);
 181         writel_relaxed(0, clps711x_intc->intmr[1]);
 182         writel_relaxed(0, clps711x_intc->intmr[2]);
 183
 184         err = irq_alloc_descs(-1, 0, ARRAY_SIZE(clps711x_irqs), numa_node_id());
 185         if (err < 0)
 186                 goto out_iounmap;
 187
 188         clps711x_intc->ops.map = clps711x_intc_irq_map;
 189         clps711x_intc->ops.xlate = irq_domain_xlate_onecell;
 190         clps711x_intc->domain =
 191                 irq_domain_add_legacy(np, ARRAY_SIZE(clps711x_irqs),
 192                                       0, 0, &clps711x_intc->ops, NULL);
 193         if (!clps711x_intc->domain) {
 194                 err = -ENOMEM;
 195                 goto out_irqfree;
 196         }
 197
 198         irq_set_default_host(clps711x_intc->domain);
 199         set_handle_irq(clps711x_irqh);
 200
 201 #ifdef CONFIG_FIQ
 202         init_FIQ(0);
 203 #endif
 204
 205         return 0;
 206
 207 out_irqfree:
 208         irq_free_descs(0, ARRAY_SIZE(clps711x_irqs));
 209
 210 out_iounmap:
 211         iounmap(clps711x_intc->base);
 212
 213 out_kfree:
 214         kfree(clps711x_intc);
 215
 216         return err;
 217 }
 218
 219 void __init clps711x_intc_init(phys_addr_t base, resource_size_t size)
 220 {
 221         BUG_ON(_clps711x_intc_init(NULL, base, size));
 222 }
 223
 224 #ifdef CONFIG_IRQCHIP
 225 static int __init clps711x_intc_init_dt(struct device_node *np,
 226                                         struct device_node *parent)
 227 {
 228         struct resource res;
 229         int err;
 230
 231         err = of_address_to_resource(np, 0, &res);
 232         if (err)
 233                 return err;
 234
 235         return _clps711x_intc_init(np, res.start, resource_size(&res));
 236 }
 237 IRQCHIP_DECLARE(clps711x, "cirrus,clps711x-intc", clps711x_intc_init_dt);
 238 #endif