arch/frv/kernel/irq-mb93091.c

   1 /* irq-mb93091.c: MB93091 FPGA interrupt handling
   2  *
   3  * Copyright (C) 2003 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
  21 #include <asm/io.h>
  22 #include <asm/system.h>
  23 #include <asm/bitops.h>
  24 #include <asm/delay.h>
  25 #include <asm/irq.h>
  26 #include <asm/irc-regs.h>
  27 #include <asm/irq-routing.h>
  28
  29 #define __reg16(ADDR) (*(volatile unsigned short *)(ADDR))
  30
  31 #define __get_IMR()     ({ __reg16(0xffc00004); })
  32 #define __set_IMR(M)    do { __reg16(0xffc00004) = (M); wmb(); } while(0)
  33 #define __get_IFR()     ({ __reg16(0xffc0000c); })
  34 #define __clr_IFR(M)    do { __reg16(0xffc0000c) = ~(M); wmb(); } while(0)
  35
  36 static void frv_fpga_doirq(struct irq_source *source);
  37 static void frv_fpga_control(struct irq_group *group, int irq, int on);
  38
  39 /*****************************************************************************/
  40 /*
  41  * FPGA IRQ multiplexor
  42  */
  43 static struct irq_source frv_fpga[4] = {
  44 #define __FPGA(X, M)                                    \
  45         [X] = {                                         \
  46                 .muxname        = "fpga."#X,            \
  47                 .irqmask        = M,                    \
  48                 .doirq          = frv_fpga_doirq,       \
  49         }
  50
  51         __FPGA(0, 0x0028),
  52         __FPGA(1, 0x0050),
  53         __FPGA(2, 0x1c00),
  54         __FPGA(3, 0x6386),
  55 };
  56
  57 static struct irq_group frv_fpga_irqs = {
  58         .first_irq      = IRQ_BASE_FPGA,
  59         .control        = frv_fpga_control,
  60         .sources = {
  61                 [ 1] = &frv_fpga[3],
  62                 [ 2] = &frv_fpga[3],
  63                 [ 3] = &frv_fpga[0],
  64                 [ 4] = &frv_fpga[1],
  65                 [ 5] = &frv_fpga[0],
  66                 [ 6] = &frv_fpga[1],
  67                 [ 7] = &frv_fpga[3],
  68                 [ 8] = &frv_fpga[3],
  69                 [ 9] = &frv_fpga[3],
  70                 [10] = &frv_fpga[2],
  71                 [11] = &frv_fpga[2],
  72                 [12] = &frv_fpga[2],
  73                 [13] = &frv_fpga[3],
  74                 [14] = &frv_fpga[3],
  75         },
  76 };
  77
  78
  79 static void frv_fpga_control(struct irq_group *group, int index, int on)
  80 {
  81         uint16_t imr = __get_IMR();
  82
  83         if (on)
  84                 imr &= ~(1 << index);
  85         else
  86                 imr |= 1 << index;
  87
  88         __set_IMR(imr);
  89 }
  90
  91 static void frv_fpga_doirq(struct irq_source *source)
  92 {
  93         uint16_t mask, imr;
  94
  95         imr = __get_IMR();
  96         mask = source->irqmask & ~imr & __get_IFR();
  97         if (mask) {
  98                 __set_IMR(imr | mask);
  99                 __clr_IFR(mask);
 100                 distribute_irqs(&frv_fpga_irqs, mask);
 101                 __set_IMR(imr);
 102         }
 103 }
 104
 105 void __init fpga_init(void)
 106 {
 107         __set_IMR(0x7ffe);
 108         __clr_IFR(0x0000);
 109
 110         frv_irq_route_external(&frv_fpga[0], IRQ_CPU_EXTERNAL0);
 111         frv_irq_route_external(&frv_fpga[1], IRQ_CPU_EXTERNAL1);
 112         frv_irq_route_external(&frv_fpga[2], IRQ_CPU_EXTERNAL2);
 113         frv_irq_route_external(&frv_fpga[3], IRQ_CPU_EXTERNAL3);
 114         frv_irq_set_group(&frv_fpga_irqs);
 115 }