arch/arm/mach-integrator/core.c

   1 /*
   2  *  linux/arch/arm/mach-integrator/core.c
   3  *
   4  *  Copyright (C) 2000-2003 Deep Blue Solutions Ltd
   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 version 2, as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/device.h>
  14 #include <linux/export.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/irq.h>
  18 #include <linux/memblock.h>
  19 #include <linux/sched.h>
  20 #include <linux/smp.h>
  21 #include <linux/amba/bus.h>
  22 #include <linux/amba/serial.h>
  23 #include <linux/io.h>
  24 #include <linux/stat.h>
  25 #include <linux/of.h>
  26 #include <linux/of_address.h>
  27
  28 #include <asm/mach-types.h>
  29 #include <asm/mach/time.h>
  30 #include <asm/pgtable.h>
  31
  32 #include "hardware.h"
  33 #include "cm.h"
  34 #include "common.h"
  35
  36 static DEFINE_RAW_SPINLOCK(cm_lock);
  37 static void __iomem *cm_base;
  38
  39 /**
  40  * cm_get - get the value from the CM_CTRL register
  41  */
  42 u32 cm_get(void)
  43 {
  44         return readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
  45 }
  46
  47 /**
  48  * cm_control - update the CM_CTRL register.
  49  * @mask: bits to change
  50  * @set: bits to set
  51  */
  52 void cm_control(u32 mask, u32 set)
  53 {
  54         unsigned long flags;
  55         u32 val;
  56
  57         raw_spin_lock_irqsave(&cm_lock, flags);
  58         val = readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET) & ~mask;
  59         writel(val | set, cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
  60         raw_spin_unlock_irqrestore(&cm_lock, flags);
  61 }
  62
  63 void cm_clear_irqs(void)
  64 {
  65         /* disable core module IRQs */
  66         writel(0xffffffffU, cm_base + INTEGRATOR_HDR_IC_OFFSET +
  67                 IRQ_ENABLE_CLEAR);
  68 }
  69
  70 static const struct of_device_id cm_match[] = {
  71         { .compatible = "arm,core-module-integrator"},
  72         { },
  73 };
  74
  75 void cm_init(void)
  76 {
  77         struct device_node *cm = of_find_matching_node(NULL, cm_match);
  78
  79         if (!cm) {
  80                 pr_crit("no core module node found in device tree\n");
  81                 return;
  82         }
  83         cm_base = of_iomap(cm, 0);
  84         if (!cm_base) {
  85                 pr_crit("could not remap core module\n");
  86                 return;
  87         }
  88         cm_clear_irqs();
  89 }
  90
  91 /*
  92  * We need to stop things allocating the low memory; ideally we need a
  93  * better implementation of GFP_DMA which does not assume that DMA-able
  94  * memory starts at zero.
  95  */
  96 void __init integrator_reserve(void)
  97 {
  98         memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
  99 }