LXR linux/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
  54static void __iomem *avic_base;
  55static struct irq_domain *domain;
  56
  57#ifdef CONFIG_FIQ
  58static int avic_set_irq_fiq(unsigned int hwirq, unsigned int type)
  59{
  60        unsigned int irqt;
  61
  62        if (hwirq >= AVIC_NUM_IRQS)
  63                return -EINVAL;
  64
  65        if (hwirq < AVIC_NUM_IRQS / 2) {
  66                irqt = imx_readl(avic_base + AVIC_INTTYPEL) & ~(1 << hwirq);
  67                imx_writel(irqt | (!!type << hwirq), avic_base + AVIC_INTTYPEL);
  68        } else {
  69                hwirq -= AVIC_NUM_IRQS / 2;
  70                irqt = imx_readl(avic_base + AVIC_INTTYPEH) & ~(1 << hwirq);
  71                imx_writel(irqt | (!!type << hwirq), avic_base + AVIC_INTTYPEH);
  72        }
  73
  74        return 0;
  75}
  76#endif /* CONFIG_FIQ */
  77
  78
  79static struct mxc_extra_irq avic_extra_irq = {
  80#ifdef CONFIG_FIQ
  81        .set_irq_fiq = avic_set_irq_fiq,
  82#endif
  83};
  84
  85#ifdef CONFIG_PM
  86static u32 avic_saved_mask_reg[2];
  87
  88static void avic_irq_suspend(struct irq_data *d)
  89{
  90        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  91        struct irq_chip_type *ct = gc->chip_types;
  92        int idx = d->hwirq >> 5;
  93
  94        avic_saved_mask_reg[idx] = imx_readl(avic_base + ct->regs.mask);
  95        imx_writel(gc->wake_active, avic_base + ct->regs.mask);
  96}
  97
  98static void avic_irq_resume(struct irq_data *d)
  99{
 100        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 101        struct irq_chip_type *ct = gc->chip_types;
 102        int idx = d->hwirq >> 5;
 103
 104        imx_writel(avic_saved_mask_reg[idx], avic_base + ct->regs.mask);
 105}
 106
 107#else
 108#define avic_irq_suspend NULL
 109#define avic_irq_resume NULL
 110#endif
 111
 112static __init void avic_init_gc(int idx, unsigned int irq_start)
 113{
 114        struct irq_chip_generic *gc;
 115        struct irq_chip_type *ct;
 116
 117        gc = irq_alloc_generic_chip("mxc-avic", 1, irq_start, avic_base,
 118                                    handle_level_irq);
 119        gc->private = &avic_extra_irq;
 120        gc->wake_enabled = IRQ_MSK(32);
 121
 122        ct = gc->chip_types;
 123        ct->chip.irq_mask = irq_gc_mask_clr_bit;
 124        ct->chip.irq_unmask = irq_gc_mask_set_bit;
 125        ct->chip.irq_ack = irq_gc_mask_clr_bit;
 126        ct->chip.irq_set_wake = irq_gc_set_wake;
 127        ct->chip.irq_suspend = avic_irq_suspend;
 128        ct->chip.irq_resume = avic_irq_resume;
 129        ct->regs.mask = !idx ? AVIC_INTENABLEL : AVIC_INTENABLEH;
 130        ct->regs.ack = ct->regs.mask;
 131
 132        irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
 133}
 134
 135static void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
 136{
 137        u32 nivector;
 138
 139        do {
 140                nivector = imx_readl(avic_base + AVIC_NIVECSR) >> 16;
 141                if (nivector == 0xffff)
 142                        break;
 143
 144                handle_domain_irq(domain, nivector, regs);
 145        } while (1);
 146}
 147
 148/*
 149 * This function initializes the AVIC hardware and disables all the
 150 * interrupts. It registers the interrupt enable and disable functions
 151 * to the kernel for each interrupt source.
 152 */
 153void __init mxc_init_irq(void __iomem *irqbase)
 154{
 155        struct device_node *np;
 156        int irq_base;
 157        int i;
 158
 159        avic_base = irqbase;
 160
 161        /* put the AVIC into the reset value with
 162         * all interrupts disabled
 163         */
 164        imx_writel(0, avic_base + AVIC_INTCNTL);
 165        imx_writel(0x1f, avic_base + AVIC_NIMASK);
 166
 167        /* disable all interrupts */
 168        imx_writel(0, avic_base + AVIC_INTENABLEH);
 169        imx_writel(0, avic_base + AVIC_INTENABLEL);
 170
 171        /* all IRQ no FIQ */
 172        imx_writel(0, avic_base + AVIC_INTTYPEH);
 173        imx_writel(0, avic_base + AVIC_INTTYPEL);
 174
 175        irq_base = irq_alloc_descs(-1, 0, AVIC_NUM_IRQS, numa_node_id());
 176        WARN_ON(irq_base < 0);
 177
 178        np = of_find_compatible_node(NULL, NULL, "fsl,avic");
 179        domain = irq_domain_add_legacy(np, AVIC_NUM_IRQS, irq_base, 0,
 180                                       &irq_domain_simple_ops, NULL);
 181        WARN_ON(!domain);
 182
 183        for (i = 0; i < AVIC_NUM_IRQS / 32; i++, irq_base += 32)
 184                avic_init_gc(i, irq_base);
 185
 186        /* Set default priority value (0) for all IRQ's */
 187        for (i = 0; i < 8; i++)
 188                imx_writel(0, avic_base + AVIC_NIPRIORITY(i));
 189
 190        set_handle_irq(avic_handle_irq);
 191
 192#ifdef CONFIG_FIQ
 193        /* Initialize FIQ */
 194        init_FIQ(FIQ_START);
 195#endif
 196
 197        printk(KERN_INFO "MXC IRQ initialized\n");
 198}
 199