arch/frv/kernel/irq-mb93493.c

   1 /* irq-mb93493.c: MB93493 companion chip interrupt handler
   2  *
   3  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/ptrace.h>
  13 #include <linux/errno.h>
  14 #include <linux/signal.h>
  15 #include <linux/sched.h>
  16 #include <linux/ioport.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/init.h>
  19 #include <linux/irq.h>
  20 #include <linux/bitops.h>
  21
  22 #include <asm/io.h>
  23 #include <asm/system.h>
  24 #include <asm/delay.h>
  25 #include <asm/irq.h>
  26 #include <asm/irc-regs.h>
  27 #include <asm/mb93493-irqs.h>
  28 #include <asm/mb93493-regs.h>
  29
  30 #define IRQ_ROUTE_ONE(X) (X##_ROUTE << (X - IRQ_BASE_MB93493))
  31
  32 #define IRQ_ROUTING                                     \
  33         (IRQ_ROUTE_ONE(IRQ_MB93493_VDC)         |       \
  34          IRQ_ROUTE_ONE(IRQ_MB93493_VCC)         |       \
  35          IRQ_ROUTE_ONE(IRQ_MB93493_AUDIO_OUT)   |       \
  36          IRQ_ROUTE_ONE(IRQ_MB93493_I2C_0)       |       \
  37          IRQ_ROUTE_ONE(IRQ_MB93493_I2C_1)       |       \
  38          IRQ_ROUTE_ONE(IRQ_MB93493_USB)         |       \
  39          IRQ_ROUTE_ONE(IRQ_MB93493_LOCAL_BUS)   |       \
  40          IRQ_ROUTE_ONE(IRQ_MB93493_PCMCIA)      |       \
  41          IRQ_ROUTE_ONE(IRQ_MB93493_GPIO)        |       \
  42          IRQ_ROUTE_ONE(IRQ_MB93493_AUDIO_IN))
  43
  44 /*
  45  * daughter board PIC operations
  46  * - there is no way to ACK interrupts in the MB93493 chip
  47  */
  48 static void frv_mb93493_mask(struct irq_data *d)
  49 {
  50         uint32_t iqsr;
  51         volatile void *piqsr;
  52
  53         if (IRQ_ROUTING & (1 << (d->irq - IRQ_BASE_MB93493)))
  54                 piqsr = __addr_MB93493_IQSR(1);
  55         else
  56                 piqsr = __addr_MB93493_IQSR(0);
  57
  58         iqsr = readl(piqsr);
  59         iqsr &= ~(1 << (d->irq - IRQ_BASE_MB93493 + 16));
  60         writel(iqsr, piqsr);
  61 }
  62
  63 static void frv_mb93493_ack(struct irq_data *d)
  64 {
  65 }
  66
  67 static void frv_mb93493_unmask(struct irq_data *d)
  68 {
  69         uint32_t iqsr;
  70         volatile void *piqsr;
  71
  72         if (IRQ_ROUTING & (1 << (d->irq - IRQ_BASE_MB93493)))
  73                 piqsr = __addr_MB93493_IQSR(1);
  74         else
  75                 piqsr = __addr_MB93493_IQSR(0);
  76
  77         iqsr = readl(piqsr);
  78         iqsr |= 1 << (d->irq - IRQ_BASE_MB93493 + 16);
  79         writel(iqsr, piqsr);
  80 }
  81
  82 static struct irq_chip frv_mb93493_pic = {
  83         .name           = "mb93093",
  84         .irq_ack        = frv_mb93493_ack,
  85         .irq_mask       = frv_mb93493_mask,
  86         .irq_mask_ack   = frv_mb93493_mask,
  87         .irq_unmask     = frv_mb93493_unmask,
  88 };
  89
  90 /*
  91  * MB93493 PIC interrupt handler
  92  */
  93 static irqreturn_t mb93493_interrupt(int irq, void *_piqsr)
  94 {
  95         volatile void *piqsr = _piqsr;
  96         uint32_t iqsr;
  97
  98         iqsr = readl(piqsr);
  99         iqsr = iqsr & (iqsr >> 16) & 0xffff;
 100
 101         /* poll all the triggered IRQs */
 102         while (iqsr) {
 103                 int irq;
 104
 105                 asm("scan %1,gr0,%0" : "=r"(irq) : "r"(iqsr));
 106                 irq = 31 - irq;
 107                 iqsr &= ~(1 << irq);
 108
 109                 generic_handle_irq(IRQ_BASE_MB93493 + irq);
 110         }
 111
 112         return IRQ_HANDLED;
 113 }
 114
 115 /*
 116  * define an interrupt action for each MB93493 PIC output
 117  * - use dev_id to indicate the MB93493 PIC input to output mappings
 118  */
 119 static struct irqaction mb93493_irq[2]  = {
 120         [0] = {
 121                 .handler        = mb93493_interrupt,
 122                 .flags          = IRQF_DISABLED | IRQF_SHARED,
 123                 .name           = "mb93493.0",
 124                 .dev_id         = (void *) __addr_MB93493_IQSR(0),
 125         },
 126         [1] = {
 127                 .handler        = mb93493_interrupt,
 128                 .flags          = IRQF_DISABLED | IRQF_SHARED,
 129                 .name           = "mb93493.1",
 130                 .dev_id         = (void *) __addr_MB93493_IQSR(1),
 131         }
 132 };
 133
 134 /*
 135  * initialise the motherboard MB93493's PIC
 136  */
 137 void __init mb93493_init(void)
 138 {
 139         int irq;
 140
 141         for (irq = IRQ_BASE_MB93493 + 0; irq <= IRQ_BASE_MB93493 + 10; irq++)
 142                 irq_set_chip_and_handler(irq, &frv_mb93493_pic,
 143                                          handle_edge_irq);
 144
 145         /* the MB93493 drives external IRQ inputs on the CPU PIC */
 146         setup_irq(IRQ_CPU_MB93493_0, &mb93493_irq[0]);
 147         setup_irq(IRQ_CPU_MB93493_1, &mb93493_irq[1]);
 148 }