arch/arm/mach-integrator/core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/arch/arm/mach-integrator/core.c
   4  *
   5  *  Copyright (C) 2000-2003 Deep Blue Solutions Ltd
   6  */
   7 #include <linux/types.h>
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/device.h>
  11 #include <linux/export.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/irq.h>
  15 #include <linux/memblock.h>
  16 #include <linux/sched.h>
  17 #include <linux/smp.h>
  18 #include <linux/amba/bus.h>
  19 #include <linux/amba/serial.h>
  20 #include <linux/io.h>
  21 #include <linux/stat.h>
  22 #include <linux/of.h>
  23 #include <linux/of_address.h>
  24
  25 #include <asm/mach-types.h>
  26 #include <asm/mach/time.h>
  27 #include <asm/pgtable.h>
  28
  29 #include "hardware.h"
  30 #include "cm.h"
  31 #include "common.h"
  32
  33 static DEFINE_RAW_SPINLOCK(cm_lock);
  34 static void __iomem *cm_base;
  35
  36 /**
  37  * cm_get - get the value from the CM_CTRL register
  38  */
  39 u32 cm_get(void)
  40 {
  41         return readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
  42 }
  43
  44 /**
  45  * cm_control - update the CM_CTRL register.
  46  * @mask: bits to change
  47  * @set: bits to set
  48  */
  49 void cm_control(u32 mask, u32 set)
  50 {
  51         unsigned long flags;
  52         u32 val;
  53
  54         raw_spin_lock_irqsave(&cm_lock, flags);
  55         val = readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET) & ~mask;
  56         writel(val | set, cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
  57         raw_spin_unlock_irqrestore(&cm_lock, flags);
  58 }
  59
  60 void cm_clear_irqs(void)
  61 {
  62         /* disable core module IRQs */
  63         writel(0xffffffffU, cm_base + INTEGRATOR_HDR_IC_OFFSET +
  64                 IRQ_ENABLE_CLEAR);
  65 }
  66
  67 static const struct of_device_id cm_match[] = {
  68         { .compatible = "arm,core-module-integrator"},
  69         { },
  70 };
  71
  72 void cm_init(void)
  73 {
  74         struct device_node *cm = of_find_matching_node(NULL, cm_match);
  75
  76         if (!cm) {
  77                 pr_crit("no core module node found in device tree\n");
  78                 return;
  79         }
  80         cm_base = of_iomap(cm, 0);
  81         if (!cm_base) {
  82                 pr_crit("could not remap core module\n");
  83                 return;
  84         }
  85         cm_clear_irqs();
  86 }
  87
  88 /*
  89  * We need to stop things allocating the low memory; ideally we need a
  90  * better implementation of GFP_DMA which does not assume that DMA-able
  91  * memory starts at zero.
  92  */
  93 void __init integrator_reserve(void)
  94 {
  95         memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
  96 }