drivers/irqchip/irq-atmel-aic.c

   1 /*
   2  * Atmel AT91 AIC (Advanced Interrupt Controller) driver
   3  *
   4  *  Copyright (C) 2004 SAN People
   5  *  Copyright (C) 2004 ATMEL
   6  *  Copyright (C) Rick Bronson
   7  *  Copyright (C) 2014 Free Electrons
   8  *
   9  *  Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
  10  *
  11  * This file is licensed under the terms of the GNU General Public
  12  * License version 2.  This program is licensed "as is" without any
  13  * warranty of any kind, whether express or implied.
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/mm.h>
  19 #include <linux/bitmap.h>
  20 #include <linux/types.h>
  21 #include <linux/irq.h>
  22 #include <linux/irqchip.h>
  23 #include <linux/of.h>
  24 #include <linux/of_address.h>
  25 #include <linux/of_irq.h>
  26 #include <linux/irqdomain.h>
  27 #include <linux/err.h>
  28 #include <linux/slab.h>
  29 #include <linux/io.h>
  30
  31 #include <asm/exception.h>
  32 #include <asm/mach/irq.h>
  33
  34 #include "irq-atmel-aic-common.h"
  35
  36 /* Number of irq lines managed by AIC */
  37 #define NR_AIC_IRQS     32
  38
  39 #define AT91_AIC_SMR(n)                 ((n) * 4)
  40
  41 #define AT91_AIC_SVR(n)                 (0x80 + ((n) * 4))
  42 #define AT91_AIC_IVR                    0x100
  43 #define AT91_AIC_FVR                    0x104
  44 #define AT91_AIC_ISR                    0x108
  45
  46 #define AT91_AIC_IPR                    0x10c
  47 #define AT91_AIC_IMR                    0x110
  48 #define AT91_AIC_CISR                   0x114
  49
  50 #define AT91_AIC_IECR                   0x120
  51 #define AT91_AIC_IDCR                   0x124
  52 #define AT91_AIC_ICCR                   0x128
  53 #define AT91_AIC_ISCR                   0x12c
  54 #define AT91_AIC_EOICR                  0x130
  55 #define AT91_AIC_SPU                    0x134
  56 #define AT91_AIC_DCR                    0x138
  57
  58 static struct irq_domain *aic_domain;
  59
  60 static asmlinkage void __exception_irq_entry
  61 aic_handle(struct pt_regs *regs)
  62 {
  63         struct irq_domain_chip_generic *dgc = aic_domain->gc;
  64         struct irq_chip_generic *gc = dgc->gc[0];
  65         u32 irqnr;
  66         u32 irqstat;
  67
  68         irqnr = irq_reg_readl(gc, AT91_AIC_IVR);
  69         irqstat = irq_reg_readl(gc, AT91_AIC_ISR);
  70
  71         if (!irqstat)
  72                 irq_reg_writel(gc, 0, AT91_AIC_EOICR);
  73         else
  74                 handle_domain_irq(aic_domain, irqnr, regs);
  75 }
  76
  77 static int aic_retrigger(struct irq_data *d)
  78 {
  79         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  80
  81         /* Enable interrupt on AIC5 */
  82         irq_gc_lock(gc);
  83         irq_reg_writel(gc, d->mask, AT91_AIC_ISCR);
  84         irq_gc_unlock(gc);
  85
  86         return 1;
  87 }
  88
  89 static int aic_set_type(struct irq_data *d, unsigned type)
  90 {
  91         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  92         unsigned int smr;
  93         int ret;
  94
  95         smr = irq_reg_readl(gc, AT91_AIC_SMR(d->hwirq));
  96         ret = aic_common_set_type(d, type, &smr);
  97         if (ret)
  98                 return ret;
  99
 100         irq_reg_writel(gc, smr, AT91_AIC_SMR(d->hwirq));
 101
 102         return 0;
 103 }
 104
 105 #ifdef CONFIG_PM
 106 static void aic_suspend(struct irq_data *d)
 107 {
 108         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 109
 110         irq_gc_lock(gc);
 111         irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IDCR);
 112         irq_reg_writel(gc, gc->wake_active, AT91_AIC_IECR);
 113         irq_gc_unlock(gc);
 114 }
 115
 116 static void aic_resume(struct irq_data *d)
 117 {
 118         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 119
 120         irq_gc_lock(gc);
 121         irq_reg_writel(gc, gc->wake_active, AT91_AIC_IDCR);
 122         irq_reg_writel(gc, gc->mask_cache, AT91_AIC_IECR);
 123         irq_gc_unlock(gc);
 124 }
 125
 126 static void aic_pm_shutdown(struct irq_data *d)
 127 {
 128         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 129
 130         irq_gc_lock(gc);
 131         irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
 132         irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
 133         irq_gc_unlock(gc);
 134 }
 135 #else
 136 #define aic_suspend             NULL
 137 #define aic_resume              NULL
 138 #define aic_pm_shutdown         NULL
 139 #endif /* CONFIG_PM */
 140
 141 static void __init aic_hw_init(struct irq_domain *domain)
 142 {
 143         struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0);
 144         int i;
 145
 146         /*
 147          * Perform 8 End Of Interrupt Command to make sure AIC
 148          * will not Lock out nIRQ
 149          */
 150         for (i = 0; i < 8; i++)
 151                 irq_reg_writel(gc, 0, AT91_AIC_EOICR);
 152
 153         /*
 154          * Spurious Interrupt ID in Spurious Vector Register.
 155          * When there is no current interrupt, the IRQ Vector Register
 156          * reads the value stored in AIC_SPU
 157          */
 158         irq_reg_writel(gc, 0xffffffff, AT91_AIC_SPU);
 159
 160         /* No debugging in AIC: Debug (Protect) Control Register */
 161         irq_reg_writel(gc, 0, AT91_AIC_DCR);
 162
 163         /* Disable and clear all interrupts initially */
 164         irq_reg_writel(gc, 0xffffffff, AT91_AIC_IDCR);
 165         irq_reg_writel(gc, 0xffffffff, AT91_AIC_ICCR);
 166
 167         for (i = 0; i < 32; i++)
 168                 irq_reg_writel(gc, i, AT91_AIC_SVR(i));
 169 }
 170
 171 static int aic_irq_domain_xlate(struct irq_domain *d,
 172                                 struct device_node *ctrlr,
 173                                 const u32 *intspec, unsigned int intsize,
 174                                 irq_hw_number_t *out_hwirq,
 175                                 unsigned int *out_type)
 176 {
 177         struct irq_domain_chip_generic *dgc = d->gc;
 178         struct irq_chip_generic *gc;
 179         unsigned long flags;
 180         unsigned smr;
 181         int idx;
 182         int ret;
 183
 184         if (!dgc)
 185                 return -EINVAL;
 186
 187         ret = aic_common_irq_domain_xlate(d, ctrlr, intspec, intsize,
 188                                           out_hwirq, out_type);
 189         if (ret)
 190                 return ret;
 191
 192         idx = intspec[0] / dgc->irqs_per_chip;
 193         if (idx >= dgc->num_chips)
 194                 return -EINVAL;
 195
 196         gc = dgc->gc[idx];
 197
 198         irq_gc_lock_irqsave(gc, flags);
 199         smr = irq_reg_readl(gc, AT91_AIC_SMR(*out_hwirq));
 200         aic_common_set_priority(intspec[2], &smr);
 201         irq_reg_writel(gc, smr, AT91_AIC_SMR(*out_hwirq));
 202         irq_gc_unlock_irqrestore(gc, flags);
 203
 204         return ret;
 205 }
 206
 207 static const struct irq_domain_ops aic_irq_ops = {
 208         .map    = irq_map_generic_chip,
 209         .xlate  = aic_irq_domain_xlate,
 210 };
 211
 212 static void __init at91rm9200_aic_irq_fixup(void)
 213 {
 214         aic_common_rtc_irq_fixup();
 215 }
 216
 217 static void __init at91sam9260_aic_irq_fixup(void)
 218 {
 219         aic_common_rtt_irq_fixup();
 220 }
 221
 222 static void __init at91sam9g45_aic_irq_fixup(void)
 223 {
 224         aic_common_rtc_irq_fixup();
 225         aic_common_rtt_irq_fixup();
 226 }
 227
 228 static const struct of_device_id aic_irq_fixups[] __initconst = {
 229         { .compatible = "atmel,at91rm9200", .data = at91rm9200_aic_irq_fixup },
 230         { .compatible = "atmel,at91sam9g45", .data = at91sam9g45_aic_irq_fixup },
 231         { .compatible = "atmel,at91sam9n12", .data = at91rm9200_aic_irq_fixup },
 232         { .compatible = "atmel,at91sam9rl", .data = at91sam9g45_aic_irq_fixup },
 233         { .compatible = "atmel,at91sam9x5", .data = at91rm9200_aic_irq_fixup },
 234         { .compatible = "atmel,at91sam9260", .data = at91sam9260_aic_irq_fixup },
 235         { .compatible = "atmel,at91sam9261", .data = at91sam9260_aic_irq_fixup },
 236         { .compatible = "atmel,at91sam9263", .data = at91sam9260_aic_irq_fixup },
 237         { .compatible = "atmel,at91sam9g20", .data = at91sam9260_aic_irq_fixup },
 238         { /* sentinel */ },
 239 };
 240
 241 static int __init aic_of_init(struct device_node *node,
 242                               struct device_node *parent)
 243 {
 244         struct irq_chip_generic *gc;
 245         struct irq_domain *domain;
 246
 247         if (aic_domain)
 248                 return -EEXIST;
 249
 250         domain = aic_common_of_init(node, &aic_irq_ops, "atmel-aic",
 251                                     NR_AIC_IRQS, aic_irq_fixups);
 252         if (IS_ERR(domain))
 253                 return PTR_ERR(domain);
 254
 255         aic_domain = domain;
 256         gc = irq_get_domain_generic_chip(domain, 0);
 257
 258         gc->chip_types[0].regs.eoi = AT91_AIC_EOICR;
 259         gc->chip_types[0].regs.enable = AT91_AIC_IECR;
 260         gc->chip_types[0].regs.disable = AT91_AIC_IDCR;
 261         gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
 262         gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
 263         gc->chip_types[0].chip.irq_retrigger = aic_retrigger;
 264         gc->chip_types[0].chip.irq_set_type = aic_set_type;
 265         gc->chip_types[0].chip.irq_suspend = aic_suspend;
 266         gc->chip_types[0].chip.irq_resume = aic_resume;
 267         gc->chip_types[0].chip.irq_pm_shutdown = aic_pm_shutdown;
 268
 269         aic_hw_init(domain);
 270         set_handle_irq(aic_handle);
 271
 272         return 0;
 273 }
 274 IRQCHIP_DECLARE(at91rm9200_aic, "atmel,at91rm9200-aic", aic_of_init);