arch/sh/boards/ec3104/irq.c

   1 /*
   2  * linux/arch/sh/boards/ec3104/irq.c
   3  * EC3104 companion chip support
   4  *
   5  * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
   6  *
   7  */
   8
   9 #include <asm/io.h>
  10 #include <asm/irq.h>
  11 #include <asm/ec3104/ec3104.h>
  12
  13 /* This is for debugging mostly;  here's the table that I intend to keep
  14  * in here:
  15  *
  16  *   index      function        base addr       power           interrupt bit
  17  *       0      power           b0ec0000        ---             00000001 (unused)
  18  *       1      irqs            b0ec1000        ---             00000002 (unused)
  19  *       2      ??              b0ec2000        b0ec0008        00000004
  20  *       3      PS2 (1)         b0ec3000        b0ec000c        00000008
  21  *       4      PS2 (2)         b0ec4000        b0ec0010        00000010
  22  *       5      ??              b0ec5000        b0ec0014        00000020
  23  *       6      I2C             b0ec6000        b0ec0018        00000040
  24  *       7      serial (1)      b0ec7000        b0ec001c        00000080
  25  *       8      serial (2)      b0ec8000        b0ec0020        00000100
  26  *       9      serial (3)      b0ec9000        b0ec0024        00000200
  27  *      10      serial (4)      b0eca000        b0ec0028        00000400
  28  *      12      GPIO (1)        b0ecc000        b0ec0030
  29  *      13      GPIO (2)        b0ecc000        b0ec0030
  30  *      16      pcmcia (1)      b0ed0000        b0ec0040        00010000
  31  *      17      pcmcia (2)      b0ed1000        b0ec0044        00020000
  32  */
  33
  34 /* I used the register names from another interrupt controller I worked with,
  35  * since it seems to be identical to the ec3104 except that all bits are
  36  * inverted:
  37  *
  38  * IRR: Interrupt Request Register (pending and enabled interrupts)
  39  * IMR: Interrupt Mask Register (which interrupts are enabled)
  40  * IPR: Interrupt Pending Register (pending interrupts, even disabled ones)
  41  *
  42  * 0 bits mean pending or enabled, 1 bits mean not pending or disabled.  all
  43  * IRQs seem to be level-triggered.
  44  */
  45
  46 #define EC3104_IRR (EC3104_BASE + 0x1000)
  47 #define EC3104_IMR (EC3104_BASE + 0x1004)
  48 #define EC3104_IPR (EC3104_BASE + 0x1008)
  49
  50 #define ctrl_readl(addr) (*(volatile u32 *)(addr))
  51 #define ctrl_writel(data,addr) (*(volatile u32 *)(addr) = (data))
  52 #define ctrl_readb(addr) (*(volatile u8 *)(addr))
  53
  54 static char *ec3104_name(unsigned index)
  55 {
  56         switch(index) {
  57         case 0:
  58                 return "power management";
  59         case 1:
  60                 return "interrupts";
  61         case 3:
  62                 return "PS2 (1)";
  63         case 4:
  64                 return "PS2 (2)";
  65         case 5:
  66                 return "I2C (1)";
  67         case 6:
  68                 return "I2C (2)";
  69         case 7:
  70                 return "serial (1)";
  71         case 8:
  72                 return "serial (2)";
  73         case 9:
  74                 return "serial (3)";
  75         case 10:
  76                 return "serial (4)";
  77         case 16:
  78                 return "pcmcia (1)";
  79         case 17:
  80                 return "pcmcia (2)";
  81         default: {
  82                 static char buf[32];
  83
  84                 sprintf(buf, "unknown (%d)", index);
  85
  86                 return buf;
  87                 }
  88         }
  89 }
  90
  91 int get_pending_interrupts(char *buf)
  92 {
  93         u32 ipr;
  94         u32 bit;
  95         char *p = buf;
  96
  97         p += sprintf(p, "pending: (");
  98
  99         ipr = ctrl_inl(EC3104_IPR);
 100
 101         for (bit = 1; bit < 32; bit++)
 102                 if (!(ipr & (1<<bit)))
 103                         p += sprintf(p, "%s ", ec3104_name(bit));
 104
 105         p += sprintf(p, ")\n");
 106
 107         return p - buf;
 108 }
 109
 110 static inline u32 ec3104_irq2mask(unsigned int irq)
 111 {
 112         return (1 << (irq - EC3104_IRQBASE));
 113 }
 114
 115 static inline void mask_ec3104_irq(unsigned int irq)
 116 {
 117         u32 mask;
 118
 119         mask = ctrl_readl(EC3104_IMR);
 120
 121         mask |= ec3104_irq2mask(irq);
 122
 123         ctrl_writel(mask, EC3104_IMR);
 124 }
 125
 126 static inline void unmask_ec3104_irq(unsigned int irq)
 127 {
 128         u32 mask;
 129
 130         mask = ctrl_readl(EC3104_IMR);
 131
 132         mask &= ~ec3104_irq2mask(irq);
 133
 134         ctrl_writel(mask, EC3104_IMR);
 135 }
 136
 137 static void disable_ec3104_irq(unsigned int irq)
 138 {
 139         mask_ec3104_irq(irq);
 140 }
 141
 142 static void enable_ec3104_irq(unsigned int irq)
 143 {
 144         unmask_ec3104_irq(irq);
 145 }
 146
 147 static void mask_and_ack_ec3104_irq(unsigned int irq)
 148 {
 149         mask_ec3104_irq(irq);
 150 }
 151
 152 static void end_ec3104_irq(unsigned int irq)
 153 {
 154         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 155                 unmask_ec3104_irq(irq);
 156 }
 157
 158 static unsigned int startup_ec3104_irq(unsigned int irq)
 159 {
 160         unmask_ec3104_irq(irq);
 161
 162         return 0;
 163 }
 164
 165 static void shutdown_ec3104_irq(unsigned int irq)
 166 {
 167         mask_ec3104_irq(irq);
 168
 169 }
 170
 171 static struct hw_interrupt_type ec3104_int = {
 172         .typename       = "EC3104",
 173         .enable         = enable_ec3104_irq,
 174         .disable        = disable_ec3104_irq,
 175         .ack            = mask_and_ack_ec3104_irq,
 176         .end            = end_ec3104_irq,
 177         .startup        = startup_ec3104_irq,
 178         .shutdown       = shutdown_ec3104_irq,
 179 };
 180
 181 /* Yuck.  the _demux API is ugly */
 182 int ec3104_irq_demux(int irq)
 183 {
 184         if (irq == EC3104_IRQ) {
 185                 unsigned int mask;
 186
 187                 mask = ctrl_readl(EC3104_IRR);
 188
 189                 if (mask == 0xffffffff)
 190                         return EC3104_IRQ;
 191                 else
 192                         return EC3104_IRQBASE + ffz(mask);
 193         }
 194
 195         return irq;
 196 }