arch/arm/plat-s3c64xx/irq-eint.c

   1 /* arch/arm/plat-s3c64xx/irq-eint.c
   2  *
   3  * Copyright 2008 Openmoko, Inc.
   4  * Copyright 2008 Simtec Electronics
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *      http://armlinux.simtec.co.uk/
   7  *
   8  * S3C64XX - Interrupt handling for IRQ_EINT(x)
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/irq.h>
  18 #include <linux/io.h>
  19
  20 #include <asm/hardware/vic.h>
  21
  22 #include <plat/regs-irqtype.h>
  23
  24 #include <mach/map.h>
  25 #include <plat/cpu.h>
  26
  27 /* GPIO is 0x7F008xxx, */
  28 #define S3C64XX_GPIOREG(x)      (S3C64XX_VA_GPIO + (x))
  29
  30 #define S3C64XX_EINT0CON0       S3C64XX_GPIOREG(0x900)
  31 #define S3C64XX_EINT0CON1       S3C64XX_GPIOREG(0x904)
  32 #define S3C64XX_EINT0FLTCON0    S3C64XX_GPIOREG(0x910)
  33 #define S3C64XX_EINT0FLTCON1    S3C64XX_GPIOREG(0x914)
  34 #define S3C64XX_EINT0FLTCON2    S3C64XX_GPIOREG(0x918)
  35 #define S3C64XX_EINT0FLTCON3    S3C64XX_GPIOREG(0x91C)
  36
  37 #define S3C64XX_EINT0MASK       S3C64XX_GPIOREG(0x920)
  38 #define S3C64XX_EINT0PEND       S3C64XX_GPIOREG(0x924)
  39
  40
  41 #define eint_offset(irq)        ((irq) - IRQ_EINT(0))
  42 #define eint_irq_to_bit(irq)    (1 << eint_offset(irq))
  43
  44 static inline void s3c_irq_eint_mask(unsigned int irq)
  45 {
  46         u32 mask;
  47
  48         mask = __raw_readl(S3C64XX_EINT0MASK);
  49         mask |= eint_irq_to_bit(irq);
  50         __raw_writel(mask, S3C64XX_EINT0MASK);
  51 }
  52
  53 static void s3c_irq_eint_unmask(unsigned int irq)
  54 {
  55         u32 mask;
  56
  57         mask = __raw_readl(S3C64XX_EINT0MASK);
  58         mask |= eint_irq_to_bit(irq);
  59         __raw_writel(mask, S3C64XX_EINT0MASK);
  60 }
  61
  62 static inline void s3c_irq_eint_ack(unsigned int irq)
  63 {
  64         __raw_writel(eint_irq_to_bit(irq), S3C64XX_EINT0PEND);
  65 }
  66
  67 static void s3c_irq_eint_maskack(unsigned int irq)
  68 {
  69         /* compiler should in-line these */
  70         s3c_irq_eint_mask(irq);
  71         s3c_irq_eint_ack(irq);
  72 }
  73
  74 static int s3c_irq_eint_set_type(unsigned int irq, unsigned int type)
  75 {
  76         int offs = eint_offset(irq);
  77         int shift;
  78         u32 ctrl, mask;
  79         u32 newvalue = 0;
  80         void __iomem *reg;
  81
  82         if (offs > 27)
  83                 return -EINVAL;
  84
  85         if (offs <= 15)
  86                 reg = S3C64XX_EINT0CON0;
  87         else
  88                 reg = S3C64XX_EINT0CON1;
  89
  90         switch (type) {
  91         case IRQ_TYPE_NONE:
  92                 printk(KERN_WARNING "No edge setting!\n");
  93                 break;
  94
  95         case IRQ_TYPE_EDGE_RISING:
  96                 newvalue = S3C2410_EXTINT_RISEEDGE;
  97                 break;
  98
  99         case IRQ_TYPE_EDGE_FALLING:
 100                 newvalue = S3C2410_EXTINT_FALLEDGE;
 101                 break;
 102
 103         case IRQ_TYPE_EDGE_BOTH:
 104                 newvalue = S3C2410_EXTINT_BOTHEDGE;
 105                 break;
 106
 107         case IRQ_TYPE_LEVEL_LOW:
 108                 newvalue = S3C2410_EXTINT_LOWLEV;
 109                 break;
 110
 111         case IRQ_TYPE_LEVEL_HIGH:
 112                 newvalue = S3C2410_EXTINT_HILEV;
 113                 break;
 114
 115         default:
 116                 printk(KERN_ERR "No such irq type %d", type);
 117                 return -1;
 118         }
 119
 120         shift = (offs / 2) * 4;
 121         mask = 0x7 << shift;
 122
 123         ctrl = __raw_readl(reg);
 124         ctrl &= ~mask;
 125         ctrl |= newvalue << shift;
 126         __raw_writel(ctrl, reg);
 127
 128         return 0;
 129 }
 130
 131 static struct irq_chip s3c_irq_eint = {
 132         .name           = "s3c-eint",
 133         .mask           = s3c_irq_eint_mask,
 134         .unmask         = s3c_irq_eint_unmask,
 135         .mask_ack       = s3c_irq_eint_maskack,
 136         .ack            = s3c_irq_eint_ack,
 137         .set_type       = s3c_irq_eint_set_type,
 138 };
 139
 140 /* s3c_irq_demux_eint
 141  *
 142  * This function demuxes the IRQ from the group0 external interrupts,
 143  * from IRQ_EINT(0) to IRQ_EINT(27). It is designed to be inlined into
 144  * the specific handlers s3c_irq_demux_eintX_Y.
 145  */
 146 static inline void s3c_irq_demux_eint(unsigned int start, unsigned int end)
 147 {
 148         u32 status = __raw_readl(S3C64XX_EINT0PEND);
 149         u32 mask = __raw_readl(S3C64XX_EINT0MASK);
 150         unsigned int irq;
 151
 152         status &= ~mask;
 153         status >>= start;
 154         status &= (1 << (end - start + 1)) - 1;
 155
 156         for (irq = IRQ_EINT(start); irq <= IRQ_EINT(end); irq++) {
 157                 if (status & 1)
 158                         generic_handle_irq(irq);
 159
 160                 status >>= 1;
 161         }
 162 }
 163
 164 static void s3c_irq_demux_eint0_3(unsigned int irq, struct irq_desc *desc)
 165 {
 166         s3c_irq_demux_eint(0, 3);
 167 }
 168
 169 static void s3c_irq_demux_eint4_11(unsigned int irq, struct irq_desc *desc)
 170 {
 171         s3c_irq_demux_eint(4, 11);
 172 }
 173
 174 static void s3c_irq_demux_eint12_19(unsigned int irq, struct irq_desc *desc)
 175 {
 176         s3c_irq_demux_eint(12, 19);
 177 }
 178
 179 static void s3c_irq_demux_eint20_27(unsigned int irq, struct irq_desc *desc)
 180 {
 181         s3c_irq_demux_eint(20, 27);
 182 }
 183
 184 int __init s3c64xx_init_irq_eint(void)
 185 {
 186         int irq;
 187
 188         for (irq = IRQ_EINT(0); irq <= IRQ_EINT(27); irq++) {
 189                 set_irq_chip(irq, &s3c_irq_eint);
 190                 set_irq_handler(irq, handle_level_irq);
 191                 set_irq_flags(irq, IRQF_VALID);
 192         }
 193
 194         set_irq_chained_handler(IRQ_EINT0_3, s3c_irq_demux_eint0_3);
 195         set_irq_chained_handler(IRQ_EINT4_11, s3c_irq_demux_eint4_11);
 196         set_irq_chained_handler(IRQ_EINT12_19, s3c_irq_demux_eint12_19);
 197         set_irq_chained_handler(IRQ_EINT20_27, s3c_irq_demux_eint20_27);
 198
 199         return 0;
 200 }
 201
 202 arch_initcall(s3c64xx_init_irq_eint);