arch/mips/au1000/pb1200/irqmap.c

   1 /*
   2  * BRIEF MODULE DESCRIPTION
   3  *      Au1xxx irq map table
   4  *
   5  *  This program is free software; you can redistribute  it and/or modify it
   6  *  under  the terms of  the GNU General  Public License as published by the
   7  *  Free Software Foundation;  either version 2 of the  License, or (at your
   8  *  option) any later version.
   9  *
  10  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
  11  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
  12  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  13  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
  14  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  15  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
  16  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  17  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
  18  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  19  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  20  *
  21  *  You should have received a copy of the  GNU General Public License along
  22  *  with this program; if not, write  to the Free Software Foundation, Inc.,
  23  *  675 Mass Ave, Cambridge, MA 02139, USA.
  24  */
  25 #include <linux/errno.h>
  26 #include <linux/init.h>
  27 #include <linux/irq.h>
  28 #include <linux/kernel_stat.h>
  29 #include <linux/module.h>
  30 #include <linux/signal.h>
  31 #include <linux/sched.h>
  32 #include <linux/types.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/ioport.h>
  35 #include <linux/timex.h>
  36 #include <linux/slab.h>
  37 #include <linux/random.h>
  38 #include <linux/delay.h>
  39 #include <linux/bitops.h>
  40
  41 #include <asm/bootinfo.h>
  42 #include <asm/io.h>
  43 #include <asm/mipsregs.h>
  44 #include <asm/system.h>
  45 #include <asm/mach-au1x00/au1000.h>
  46
  47 #ifdef CONFIG_MIPS_PB1200
  48 #include <asm/mach-pb1x00/pb1200.h>
  49 #endif
  50
  51 #ifdef CONFIG_MIPS_DB1200
  52 #include <asm/mach-db1x00/db1200.h>
  53 #define PB1200_INT_BEGIN DB1200_INT_BEGIN
  54 #define PB1200_INT_END DB1200_INT_END
  55 #endif
  56
  57 struct au1xxx_irqmap __initdata au1xxx_irq_map[] = {
  58         { AU1000_GPIO_7, INTC_INT_LOW_LEVEL, 0 }, // This is exteranl interrupt cascade
  59 };
  60
  61 int __initdata au1xxx_nr_irqs = ARRAY_SIZE(au1xxx_irq_map);
  62
  63 /*
  64  *      Support for External interrupts on the PbAu1200 Development platform.
  65  */
  66 static volatile int pb1200_cascade_en=0;
  67
  68 irqreturn_t pb1200_cascade_handler( int irq, void *dev_id)
  69 {
  70         unsigned short bisr = bcsr->int_status;
  71         int extirq_nr = 0;
  72
  73         /* Clear all the edge interrupts. This has no effect on level */
  74         bcsr->int_status = bisr;
  75         for( ; bisr; bisr &= (bisr-1) )
  76         {
  77                 extirq_nr = PB1200_INT_BEGIN + __ffs(bisr);
  78                 /* Ack and dispatch IRQ */
  79                 do_IRQ(extirq_nr);
  80         }
  81
  82         return IRQ_RETVAL(1);
  83 }
  84
  85 inline void pb1200_enable_irq(unsigned int irq_nr)
  86 {
  87         bcsr->intset_mask = 1<<(irq_nr - PB1200_INT_BEGIN);
  88         bcsr->intset = 1<<(irq_nr - PB1200_INT_BEGIN);
  89 }
  90
  91 inline void pb1200_disable_irq(unsigned int irq_nr)
  92 {
  93         bcsr->intclr_mask = 1<<(irq_nr - PB1200_INT_BEGIN);
  94         bcsr->intclr = 1<<(irq_nr - PB1200_INT_BEGIN);
  95 }
  96
  97 static unsigned int pb1200_setup_cascade(void)
  98 {
  99         int err;
 100
 101         err = request_irq(AU1000_GPIO_7, &pb1200_cascade_handler,
 102                           0, "Pb1200 Cascade", &pb1200_cascade_handler);
 103         if (err)
 104                 return err;
 105
 106         return 0;
 107 }
 108
 109 static unsigned int pb1200_startup_irq(unsigned int irq)
 110 {
 111         if (++pb1200_cascade_en == 1) {
 112                 int res;
 113
 114                 res = pb1200_setup_cascade();
 115                 if (res)
 116                         return res;
 117         }
 118
 119         pb1200_enable_irq(irq);
 120
 121         return 0;
 122 }
 123
 124 static void pb1200_shutdown_irq(unsigned int irq)
 125 {
 126         pb1200_disable_irq(irq);
 127         if (--pb1200_cascade_en == 0)
 128                 free_irq(AU1000_GPIO_7, &pb1200_cascade_handler);
 129 }
 130
 131 static struct irq_chip external_irq_type = {
 132 #ifdef CONFIG_MIPS_PB1200
 133         .name = "Pb1200 Ext",
 134 #endif
 135 #ifdef CONFIG_MIPS_DB1200
 136         .name = "Db1200 Ext",
 137 #endif
 138         .startup  = pb1200_startup_irq,
 139         .shutdown = pb1200_shutdown_irq,
 140         .ack      = pb1200_disable_irq,
 141         .mask     = pb1200_disable_irq,
 142         .mask_ack = pb1200_disable_irq,
 143         .unmask   = pb1200_enable_irq,
 144 };
 145
 146 void _board_init_irq(void)
 147 {
 148         unsigned int irq;
 149
 150 #ifdef CONFIG_MIPS_PB1200
 151         /* We have a problem with CPLD rev3. Enable a workaround */
 152         if (((bcsr->whoami & BCSR_WHOAMI_CPLD) >> 4) <= 3) {
 153                 printk("\nWARNING!!!\n");
 154                 printk("\nWARNING!!!\n");
 155                 printk("\nWARNING!!!\n");
 156                 printk("\nWARNING!!!\n");
 157                 printk("\nWARNING!!!\n");
 158                 printk("\nWARNING!!!\n");
 159                 printk("Pb1200 must be at CPLD rev4. Please have Pb1200\n");
 160                 printk("updated to latest revision. This software will not\n");
 161                 printk("work on anything less than CPLD rev4\n");
 162                 printk("\nWARNING!!!\n");
 163                 printk("\nWARNING!!!\n");
 164                 printk("\nWARNING!!!\n");
 165                 printk("\nWARNING!!!\n");
 166                 printk("\nWARNING!!!\n");
 167                 printk("\nWARNING!!!\n");
 168                 panic("Game over.  Your score is 0.");
 169         }
 170 #endif
 171
 172         for (irq = PB1200_INT_BEGIN; irq <= PB1200_INT_END; irq++) {
 173                 set_irq_chip_and_handler(irq, &external_irq_type,
 174                                          handle_level_irq);
 175                 pb1200_disable_irq(irq);
 176         }
 177
 178         /*
 179          * GPIO_7 can not be hooked here, so it is hooked upon first
 180          * request of any source attached to the cascade
 181          */
 182 }