arch/arm/mach-davinci/irq.c

   1 /*
   2  * Interrupt handler for DaVinci boards.
   3  *
   4  * Copyright (C) 2006 Texas Instruments.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  *
  20  */
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/irq.h>
  25 #include <linux/io.h>
  26
  27 #include <mach/hardware.h>
  28 #include <mach/cputype.h>
  29 #include <mach/common.h>
  30 #include <asm/mach/irq.h>
  31
  32 #define FIQ_REG0_OFFSET         0x0000
  33 #define FIQ_REG1_OFFSET         0x0004
  34 #define IRQ_REG0_OFFSET         0x0008
  35 #define IRQ_REG1_OFFSET         0x000C
  36 #define IRQ_ENT_REG0_OFFSET     0x0018
  37 #define IRQ_ENT_REG1_OFFSET     0x001C
  38 #define IRQ_INCTL_REG_OFFSET    0x0020
  39 #define IRQ_EABASE_REG_OFFSET   0x0024
  40 #define IRQ_INTPRI0_REG_OFFSET  0x0030
  41 #define IRQ_INTPRI7_REG_OFFSET  0x004C
  42
  43 static inline void davinci_irq_writel(unsigned long value, int offset)
  44 {
  45         __raw_writel(value, davinci_intc_base + offset);
  46 }
  47
  48 static __init void
  49 davinci_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
  50 {
  51         struct irq_chip_generic *gc;
  52         struct irq_chip_type *ct;
  53
  54         gc = irq_alloc_generic_chip("AINTC", 1, irq_start, base, handle_edge_irq);
  55         ct = gc->chip_types;
  56         ct->chip.irq_ack = irq_gc_ack;
  57         ct->chip.irq_mask = irq_gc_mask_clr_bit;
  58         ct->chip.irq_unmask = irq_gc_mask_set_bit;
  59
  60         ct->regs.ack = IRQ_REG0_OFFSET;
  61         ct->regs.mask = IRQ_ENT_REG0_OFFSET;
  62         irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
  63                                IRQ_NOREQUEST | IRQ_NOPROBE, 0);
  64 }
  65
  66 /* ARM Interrupt Controller Initialization */
  67 void __init davinci_irq_init(void)
  68 {
  69         unsigned i, j;
  70         const u8 *davinci_def_priorities = davinci_soc_info.intc_irq_prios;
  71
  72         davinci_intc_type = DAVINCI_INTC_TYPE_AINTC;
  73         davinci_intc_base = ioremap(davinci_soc_info.intc_base, SZ_4K);
  74         if (WARN_ON(!davinci_intc_base))
  75                 return;
  76
  77         /* Clear all interrupt requests */
  78         davinci_irq_writel(~0x0, FIQ_REG0_OFFSET);
  79         davinci_irq_writel(~0x0, FIQ_REG1_OFFSET);
  80         davinci_irq_writel(~0x0, IRQ_REG0_OFFSET);
  81         davinci_irq_writel(~0x0, IRQ_REG1_OFFSET);
  82
  83         /* Disable all interrupts */
  84         davinci_irq_writel(0x0, IRQ_ENT_REG0_OFFSET);
  85         davinci_irq_writel(0x0, IRQ_ENT_REG1_OFFSET);
  86
  87         /* Interrupts disabled immediately, IRQ entry reflects all */
  88         davinci_irq_writel(0x0, IRQ_INCTL_REG_OFFSET);
  89
  90         /* we don't use the hardware vector table, just its entry addresses */
  91         davinci_irq_writel(0, IRQ_EABASE_REG_OFFSET);
  92
  93         /* Clear all interrupt requests */
  94         davinci_irq_writel(~0x0, FIQ_REG0_OFFSET);
  95         davinci_irq_writel(~0x0, FIQ_REG1_OFFSET);
  96         davinci_irq_writel(~0x0, IRQ_REG0_OFFSET);
  97         davinci_irq_writel(~0x0, IRQ_REG1_OFFSET);
  98
  99         for (i = IRQ_INTPRI0_REG_OFFSET; i <= IRQ_INTPRI7_REG_OFFSET; i += 4) {
 100                 u32             pri;
 101
 102                 for (j = 0, pri = 0; j < 32; j += 4, davinci_def_priorities++)
 103                         pri |= (*davinci_def_priorities & 0x07) << j;
 104                 davinci_irq_writel(pri, i);
 105         }
 106
 107         for (i = 0, j = 0; i < davinci_soc_info.intc_irq_num; i += 32, j += 0x04)
 108                 davinci_alloc_gc(davinci_intc_base + j, i, 32);
 109
 110         irq_set_handler(IRQ_TINT1_TINT34, handle_level_irq);
 111 }