arch/mips/lantiq/xway/pmu.c

   1 /*
   2  *  This program is free software; you can redistribute it and/or modify it
   3  *  under the terms of the GNU General Public License version 2 as published
   4  *  by the Free Software Foundation.
   5  *
   6  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/ioport.h>
  12
  13 #include <lantiq_soc.h>
  14
  15 /* PMU - the power management unit allows us to turn part of the core
  16  * on and off
  17  */
  18
  19 /* the enable / disable registers */
  20 #define LTQ_PMU_PWDCR   0x1C
  21 #define LTQ_PMU_PWDSR   0x20
  22
  23 #define ltq_pmu_w32(x, y)       ltq_w32((x), ltq_pmu_membase + (y))
  24 #define ltq_pmu_r32(x)          ltq_r32(ltq_pmu_membase + (x))
  25
  26 static struct resource ltq_pmu_resource = {
  27         .name   = "pmu",
  28         .start  = LTQ_PMU_BASE_ADDR,
  29         .end    = LTQ_PMU_BASE_ADDR + LTQ_PMU_SIZE - 1,
  30         .flags  = IORESOURCE_MEM,
  31 };
  32
  33 static void __iomem *ltq_pmu_membase;
  34
  35 void ltq_pmu_enable(unsigned int module)
  36 {
  37         int err = 1000000;
  38
  39         ltq_pmu_w32(ltq_pmu_r32(LTQ_PMU_PWDCR) & ~module, LTQ_PMU_PWDCR);
  40         do {} while (--err && (ltq_pmu_r32(LTQ_PMU_PWDSR) & module));
  41
  42         if (!err)
  43                 panic("activating PMU module failed!");
  44 }
  45 EXPORT_SYMBOL(ltq_pmu_enable);
  46
  47 void ltq_pmu_disable(unsigned int module)
  48 {
  49         ltq_pmu_w32(ltq_pmu_r32(LTQ_PMU_PWDCR) | module, LTQ_PMU_PWDCR);
  50 }
  51 EXPORT_SYMBOL(ltq_pmu_disable);
  52
  53 int __init ltq_pmu_init(void)
  54 {
  55         if (insert_resource(&iomem_resource, &ltq_pmu_resource) < 0)
  56                 panic("Failed to insert pmu memory");
  57
  58         if (request_mem_region(ltq_pmu_resource.start,
  59                         resource_size(&ltq_pmu_resource), "pmu") < 0)
  60                 panic("Failed to request pmu memory");
  61
  62         ltq_pmu_membase = ioremap_nocache(ltq_pmu_resource.start,
  63                                 resource_size(&ltq_pmu_resource));
  64         if (!ltq_pmu_membase)
  65                 panic("Failed to remap pmu memory");
  66         return 0;
  67 }
  68
  69 core_initcall(ltq_pmu_init);