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/version.h>
  12 #include <linux/ioport.h>
  13
  14 #include <lantiq_soc.h>
  15
  16 /* PMU - the power management unit allows us to turn part of the core
  17  * on and off
  18  */
  19
  20 /* the enable / disable registers */
  21 #define LTQ_PMU_PWDCR   0x1C
  22 #define LTQ_PMU_PWDSR   0x20
  23
  24 #define ltq_pmu_w32(x, y)       ltq_w32((x), ltq_pmu_membase + (y))
  25 #define ltq_pmu_r32(x)          ltq_r32(ltq_pmu_membase + (x))
  26
  27 static struct resource ltq_pmu_resource = {
  28         .name   = "pmu",
  29         .start  = LTQ_PMU_BASE_ADDR,
  30         .end    = LTQ_PMU_BASE_ADDR + LTQ_PMU_SIZE - 1,
  31         .flags  = IORESOURCE_MEM,
  32 };
  33
  34 static void __iomem *ltq_pmu_membase;
  35
  36 void ltq_pmu_enable(unsigned int module)
  37 {
  38         int err = 1000000;
  39
  40         ltq_pmu_w32(ltq_pmu_r32(LTQ_PMU_PWDCR) & ~module, LTQ_PMU_PWDCR);
  41         do {} while (--err && (ltq_pmu_r32(LTQ_PMU_PWDSR) & module));
  42
  43         if (!err)
  44                 panic("activating PMU module failed!\n");
  45 }
  46 EXPORT_SYMBOL(ltq_pmu_enable);
  47
  48 void ltq_pmu_disable(unsigned int module)
  49 {
  50         ltq_pmu_w32(ltq_pmu_r32(LTQ_PMU_PWDCR) | module, LTQ_PMU_PWDCR);
  51 }
  52 EXPORT_SYMBOL(ltq_pmu_disable);
  53
  54 int __init ltq_pmu_init(void)
  55 {
  56         if (insert_resource(&iomem_resource, &ltq_pmu_resource) < 0)
  57                 panic("Failed to insert pmu memory\n");
  58
  59         if (request_mem_region(ltq_pmu_resource.start,
  60                         resource_size(&ltq_pmu_resource), "pmu") < 0)
  61                 panic("Failed to request pmu memory\n");
  62
  63         ltq_pmu_membase = ioremap_nocache(ltq_pmu_resource.start,
  64                                 resource_size(&ltq_pmu_resource));
  65         if (!ltq_pmu_membase)
  66                 panic("Failed to remap pmu memory\n");
  67         return 0;
  68 }
  69
  70 core_initcall(ltq_pmu_init);