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_MXC_IRQ_PRIOR
  58static int avic_irq_set_priority(unsigned char irq, unsigned char prio)
  59{
  60        struct irq_data *d = irq_get_irq_data(irq);
  61        unsigned int temp;
  62        unsigned int mask = 0x0F << irq % 8 * 4;
  63
  64        irq = d->hwirq;
  65
  66        if (irq >= AVIC_NUM_IRQS)
  67                return -EINVAL;
  68
  69        temp = __raw_readl(avic_base + AVIC_NIPRIORITY(irq / 8));
  70        temp &= ~mask;
  71        temp |= prio & mask;
  72
  73        __raw_writel(temp, avic_base + AVIC_NIPRIORITY(irq / 8));
  74
  75        return 0;
  76}
  77#endif
  78
  79#ifdef CONFIG_FIQ
  80static int avic_set_irq_fiq(unsigned int irq, unsigned int type)
  81{
  82        struct irq_data *d = irq_get_irq_data(irq);
  83        unsigned int irqt;
  84
  85        irq = d->hwirq;
  86
  87        if (irq >= AVIC_NUM_IRQS)
  88                return -EINVAL;
  89
  90        if (irq < AVIC_NUM_IRQS / 2) {
  91                irqt = __raw_readl(avic_base + AVIC_INTTYPEL) & ~(1 << irq);
  92                __raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEL);
  93        } else {
  94                irq -= AVIC_NUM_IRQS / 2;
  95                irqt = __raw_readl(avic_base + AVIC_INTTYPEH) & ~(1 << irq);
  96                __raw_writel(irqt | (!!type << irq), avic_base + AVIC_INTTYPEH);
  97        }
  98
  99        return 0;
 100}
 101#endif /* CONFIG_FIQ */
 102
 103
 104static struct mxc_extra_irq avic_extra_irq = {
 105#ifdef CONFIG_MXC_IRQ_PRIOR
 106        .set_priority = avic_irq_set_priority,
 107#endif
 108#ifdef CONFIG_FIQ
 109        .set_irq_fiq = avic_set_irq_fiq,
 110#endif
 111};
 112
 113#ifdef CONFIG_PM
 114static u32 avic_saved_mask_reg[2];
 115
 116static 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
 126static 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
 140static __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
 163asmlinkage 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 */
 181void __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}
 225