arch/arm/mach-omap2/pmu.c

   1 /*
   2  * OMAP2 ARM Performance Monitoring Unit (PMU) Support
   3  *
   4  * Copyright (C) 2012 Texas Instruments, Inc.
   5  *
   6  * Contacts:
   7  * Jon Hunter <jon-hunter@ti.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  */
  14
  15 #include <asm/pmu.h>
  16
  17 #include <plat/omap_hwmod.h>
  18 #include <plat/omap_device.h>
  19
  20 static char *omap2_pmu_oh_names[] = {"mpu"};
  21 static char *omap3_pmu_oh_names[] = {"mpu", "debugss"};
  22 static struct platform_device *omap_pmu_dev;
  23
  24 /**
  25  * omap2_init_pmu - creates and registers PMU platform device
  26  * @oh_num:     Number of OMAP HWMODs required to create PMU device
  27  * @oh_names:   Array of OMAP HWMODS names required to create PMU device
  28  *
  29  * Uses OMAP HWMOD framework to create and register an ARM PMU device
  30  * from a list of HWMOD names passed. Currently supports OMAP2 and
  31  * OMAP3 devices.
  32  */
  33 static int __init omap2_init_pmu(unsigned oh_num, char *oh_names[])
  34 {
  35         int i;
  36         struct omap_hwmod *oh[2];
  37         char *dev_name = "arm-pmu";
  38
  39         if ((!oh_num) || (oh_num > 2))
  40                 return -EINVAL;
  41
  42         for (i = 0; i < oh_num; i++) {
  43                 oh[i] = omap_hwmod_lookup(oh_names[i]);
  44                 if (!oh[i]) {
  45                         pr_err("Could not look up %s hwmod\n", oh_names[i]);
  46                         return -ENODEV;
  47                 }
  48         }
  49
  50         omap_pmu_dev = omap_device_build_ss(dev_name, -1, oh, oh_num, NULL, 0,
  51                                             NULL, 0, 0);
  52         WARN(IS_ERR(omap_pmu_dev), "Can't build omap_device for %s.\n",
  53              dev_name);
  54
  55         return IS_ERR(omap_pmu_dev) ? PTR_ERR(omap_pmu_dev) : 0;
  56 }
  57
  58 static int __init omap_init_pmu(void)
  59 {
  60         unsigned oh_num;
  61         char **oh_names;
  62
  63         /*
  64          * To create an ARM-PMU device the following HWMODs
  65          * are required for the various OMAP2+ devices.
  66          *
  67          * OMAP24xx:    mpu
  68          * OMAP3xxx:    mpu, debugss
  69          */
  70         if (cpu_is_omap24xx()) {
  71                 oh_num = ARRAY_SIZE(omap2_pmu_oh_names);
  72                 oh_names = omap2_pmu_oh_names;
  73         } else if (cpu_is_omap34xx()) {
  74                 oh_num = ARRAY_SIZE(omap3_pmu_oh_names);
  75                 oh_names = omap3_pmu_oh_names;
  76         } else {
  77                 return 0;
  78         }
  79
  80         return omap2_init_pmu(oh_num, oh_names);
  81 }
  82 subsys_initcall(omap_init_pmu);