target/linux/ramips/files/arch/mips/ralink/common/intc.c

   1 /*
   2  * Ralink SoC Interrupt controller routines
   3  *
   4  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published
   8  * by the Free Software Foundation.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/io.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/irq.h>
  16 #include <linux/bitops.h>
  17
  18 #include <asm/irq_cpu.h>
  19 #include <asm/mipsregs.h>
  20
  21 #include <asm/mach-ralink/common.h>
  22
  23 /* INTC register offsets */
  24 #define INTC_REG_STATUS0        0x00
  25 #define INTC_REG_STATUS1        0x04
  26 #define INTC_REG_TYPE           0x20
  27 #define INTC_REG_RAW_STATUS     0x30
  28 #define INTC_REG_ENABLE         0x34
  29 #define INTC_REG_DISABLE        0x38
  30
  31 #define INTC_INT_GLOBAL         BIT(31)
  32 #define INTC_IRQ_COUNT          32
  33
  34 static unsigned int ramips_intc_irq_base;
  35 static void __iomem *ramips_intc_base;
  36
  37 static inline void ramips_intc_wr(u32 val, unsigned reg)
  38 {
  39         __raw_writel(val, ramips_intc_base + reg);
  40 }
  41
  42 static inline u32 ramips_intc_rr(unsigned reg)
  43 {
  44         return __raw_readl(ramips_intc_base + reg);
  45 }
  46
  47 static void ramips_intc_irq_unmask(struct irq_data *d)
  48 {
  49         unsigned int irq = d->irq - ramips_intc_irq_base;
  50
  51         ramips_intc_wr((1 << irq), INTC_REG_ENABLE);
  52 }
  53
  54 static void ramips_intc_irq_mask(struct irq_data *d)
  55 {
  56         unsigned int irq = d->irq - ramips_intc_irq_base;
  57
  58         ramips_intc_wr((1 << irq), INTC_REG_DISABLE);
  59 }
  60
  61 static struct irq_chip ramips_intc_irq_chip = {
  62         .name           = "INTC",
  63         .irq_unmask     = ramips_intc_irq_unmask,
  64         .irq_mask       = ramips_intc_irq_mask,
  65         .irq_mask_ack   = ramips_intc_irq_mask,
  66 };
  67
  68 static struct irqaction ramips_intc_irqaction = {
  69         .handler        = no_action,
  70         .name           = "cascade [INTC]",
  71 };
  72
  73 void __init ramips_intc_irq_init(unsigned intc_base, unsigned irq,
  74                                  unsigned irq_base)
  75 {
  76         int i;
  77
  78         ramips_intc_base = ioremap_nocache(intc_base, PAGE_SIZE);
  79         ramips_intc_irq_base = irq_base;
  80
  81         /* disable all interrupts */
  82         ramips_intc_wr(~0, INTC_REG_DISABLE);
  83
  84         /* route all INTC interrupts to MIPS HW0 interrupt */
  85         ramips_intc_wr(0, INTC_REG_TYPE);
  86
  87         for (i = ramips_intc_irq_base;
  88              i < ramips_intc_irq_base + INTC_IRQ_COUNT; i++)
  89                 irq_set_chip_and_handler(i, &ramips_intc_irq_chip,
  90                                          handle_level_irq);
  91
  92         setup_irq(irq, &ramips_intc_irqaction);
  93         ramips_intc_wr(INTC_INT_GLOBAL, INTC_REG_ENABLE);
  94 }
  95
  96 u32 ramips_intc_get_status(void)
  97 {
  98         return ramips_intc_rr(INTC_REG_STATUS0);
  99 }