arch/arm/mach-imx/avic.c

   1 /*
   2  * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3  * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  17  * MA  02110-1301, USA.
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/irq.h>
  22 #include <linux/irqdomain.h>
  23 #include <linux/io.h>
  24 #include <linux/of.h>
  25 #include <asm/mach/irq.h>
  26 #include <asm/exception.h>
  27
  28 #include "common.h"
  29 #include "hardware.h"
  30 #include "irq-common.h"
  31
  32 #define AVIC_INTCNTL            0x00    /* int control reg */
  33 #define AVIC_NIMASK             0x04    /* int mask reg */
  34 #define AVIC_INTENNUM           0x08    /* int enable number reg */
  35 #define AVIC_INTDISNUM          0x0C    /* int disable number reg */
  36 #define AVIC_INTENABLEH         0x10    /* int enable reg high */
  37 #define AVIC_INTENABLEL         0x14    /* int enable reg low */
  38 #define AVIC_INTTYPEH           0x18    /* int type reg high */
  39 #define AVIC_INTTYPEL           0x1C    /* int type reg low */
  40 #define AVIC_NIPRIORITY(x)      (0x20 + 4 * (7 - (x))) /* int priority */
  41 #define AVIC_NIVECSR            0x40    /* norm int vector/status */
  42 #define AVIC_FIVECSR            0x44    /* fast int vector/status */
  43 #define AVIC_INTSRCH            0x48    /* int source reg high */
  44 #define AVIC_INTSRCL            0x4C    /* int source reg low */
  45 #define AVIC_INTFRCH            0x50    /* int force reg high */
  46 #define AVIC_INTFRCL            0x54    /* int force reg low */
  47 #define AVIC_NIPNDH             0x58    /* norm int pending high */
  48 #define AVIC_NIPNDL             0x5C    /* norm int pending low */
  49 #define AVIC_FIPNDH             0x60    /* fast int pending high */
  50 #define AVIC_FIPNDL             0x64    /* fast int pending low */
  51
  52 #define AVIC_NUM_IRQS 64
  53
  54 void __iomem *avic_base;
  55 static struct irq_domain *domain;
  56
  57 static u32 avic_saved_mask_reg[2];
  58
  59 #ifdef CONFIG_MXC_IRQ_PRIOR
  60 static int avic_irq_set_priority(unsigned char irq, unsigned char prio)
  61 {
  62         struct irq_data *d = irq_get_irq_data(irq);
  63         unsigned int temp;
  64         unsigned int mask = 0x0F << irq % 8 * 4;
  65
  66         irq = d->hwirq;
  67
  68         if (irq >= AVIC_NUM_IRQS)
  69                 return -EINVAL;
  70
  71         temp = __raw_readl(avic_base + AVIC_NIPRIORITY(irq / 8));
  72         temp &= ~mask;
  73         temp |= prio & mask;
  74
  75         __raw_writel(temp, avic_base + AVIC_NIPRIORITY(irq / 8));
  76
  77         return 0;
  78 }
  79 #endif
  80
  81 #ifdef CONFIG_FIQ
  82 static int avic_set_irq_fiq(unsigned int irq, unsigned int type)
  83 {
  84         struct irq_data *d = irq_get_irq_data(irq);
  85         unsigned int irqt;
  86
  87         irq = d->hwirq;
  88
  89         if (irq >= AVIC_NUM_IRQS)
  90                 return -EINVAL;
  91
  92         if (irq < AVIC_NUM_IRQS / 2) {
  93                 irqt = __raw_readl(avic_base + AVIC_INTTYPEL) & ~(1 << irq);
  94                 __raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEL);
  95         } else {
  96                 irq -= AVIC_NUM_IRQS / 2;
  97                 irqt = __raw_readl(avic_base + AVIC_INTTYPEH) & ~(1 << irq);
  98                 __raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEH);
  99         }
 100
 101         return 0;
 102 }
 103 #endif /* CONFIG_FIQ */
 104
 105
 106 static struct mxc_extra_irq avic_extra_irq = {
 107 #ifdef CONFIG_MXC_IRQ_PRIOR
 108         .set_priority = avic_irq_set_priority,
 109 #endif
 110 #ifdef CONFIG_FIQ
 111         .set_irq_fiq = avic_set_irq_fiq,
 112 #endif
 113 };
 114
 115 #ifdef CONFIG_PM
 116 static void avic_irq_suspend(struct irq_data *d)
 117 {
 118         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 119         struct irq_chip_type *ct = gc->chip_types;
 120         int idx = d->hwirq >> 5;
 121
 122         avic_saved_mask_reg[idx] = __raw_readl(avic_base + ct->regs.mask);
 123         __raw_writel(gc->wake_active, avic_base + ct->regs.mask);
 124 }
 125
 126 static void avic_irq_resume(struct irq_data *d)
 127 {
 128         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 129         struct irq_chip_type *ct = gc->chip_types;
 130         int idx = d->hwirq >> 5;
 131
 132         __raw_writel(avic_saved_mask_reg[idx], avic_base + ct->regs.mask);
 133 }
 134
 135 #else
 136 #define avic_irq_suspend NULL
 137 #define avic_irq_resume NULL
 138 #endif
 139
 140 static __init void avic_init_gc(int idx, unsigned int irq_start)
 141 {
 142         struct irq_chip_generic *gc;
 143         struct irq_chip_type *ct;
 144
 145         gc = irq_alloc_generic_chip("mxc-avic", 1, irq_start, avic_base,
 146                                     handle_level_irq);
 147         gc->private = &avic_extra_irq;
 148         gc->wake_enabled = IRQ_MSK(32);
 149
 150         ct = gc->chip_types;
 151         ct->chip.irq_mask = irq_gc_mask_clr_bit;
 152         ct->chip.irq_unmask = irq_gc_mask_set_bit;
 153         ct->chip.irq_ack = irq_gc_mask_clr_bit;
 154         ct->chip.irq_set_wake = irq_gc_set_wake;
 155         ct->chip.irq_suspend = avic_irq_suspend;
 156         ct->chip.irq_resume = avic_irq_resume;
 157         ct->regs.mask = !idx ? AVIC_INTENABLEL : AVIC_INTENABLEH;
 158         ct->regs.ack = ct->regs.mask;
 159
 160         irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
 161 }
 162
 163 asmlinkage void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
 164 {
 165         u32 nivector;
 166
 167         do {
 168                 nivector = __raw_readl(avic_base + AVIC_NIVECSR) >> 16;
 169                 if (nivector == 0xffff)
 170                         break;
 171
 172                 handle_IRQ(irq_find_mapping(domain, nivector), regs);
 173         } while (1);
 174 }
 175
 176 /*
 177  * This function initializes the AVIC hardware and disables all the
 178  * interrupts. It registers the interrupt enable and disable functions
 179  * to the kernel for each interrupt source.
 180  */
 181 void __init mxc_init_irq(void __iomem *irqbase)
 182 {
 183         struct device_node *np;
 184         int irq_base;
 185         int i;
 186
 187         avic_base = irqbase;
 188
 189         /* put the AVIC into the reset value with
 190          * all interrupts disabled
 191          */
 192         __raw_writel(0, avic_base + AVIC_INTCNTL);
 193         __raw_writel(0x1f, avic_base + AVIC_NIMASK);
 194
 195         /* disable all interrupts */
 196         __raw_writel(0, avic_base + AVIC_INTENABLEH);
 197         __raw_writel(0, avic_base + AVIC_INTENABLEL);
 198
 199         /* all IRQ no FIQ */
 200         __raw_writel(0, avic_base + AVIC_INTTYPEH);
 201         __raw_writel(0, avic_base + AVIC_INTTYPEL);
 202
 203         irq_base = irq_alloc_descs(-1, 0, AVIC_NUM_IRQS, numa_node_id());
 204         WARN_ON(irq_base < 0);
 205
 206         np = of_find_compatible_node(NULL, NULL, "fsl,avic");
 207         domain = irq_domain_add_legacy(np, AVIC_NUM_IRQS, irq_base, 0,
 208                                        &irq_domain_simple_ops, NULL);
 209         WARN_ON(!domain);
 210
 211         for (i = 0; i < AVIC_NUM_IRQS / 32; i++, irq_base += 32)
 212                 avic_init_gc(i, irq_base);
 213
 214         /* Set default priority value (0) for all IRQ's */
 215         for (i = 0; i < 8; i++)
 216                 __raw_writel(0, avic_base + AVIC_NIPRIORITY(i));
 217
 218 #ifdef CONFIG_FIQ
 219         /* Initialize FIQ */
 220         init_FIQ(FIQ_START);
 221 #endif
 222
 223         printk(KERN_INFO "MXC IRQ initialized\n");
 224 }