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 #include <linux/pm_runtime.h>
  15
  16 #include <asm/pmu.h>
  17
  18 #include "omap_hwmod.h"
  19 #include "omap_device.h"
  20
  21 static char *omap2_pmu_oh_names[] = {"mpu"};
  22 static char *omap3_pmu_oh_names[] = {"mpu", "debugss"};
  23 static char *omap4430_pmu_oh_names[] = {"l3_main_3", "l3_instr", "debugss"};
  24 static struct platform_device *omap_pmu_dev;
  25
  26 /**
  27  * omap2_init_pmu - creates and registers PMU platform device
  28  * @oh_num:     Number of OMAP HWMODs required to create PMU device
  29  * @oh_names:   Array of OMAP HWMODS names required to create PMU device
  30  *
  31  * Uses OMAP HWMOD framework to create and register an ARM PMU device
  32  * from a list of HWMOD names passed. Currently supports OMAP2, OMAP3
  33  * and OMAP4 devices.
  34  */
  35 static int __init omap2_init_pmu(unsigned oh_num, char *oh_names[])
  36 {
  37         int i;
  38         struct omap_hwmod *oh[3];
  39         char *dev_name = "arm-pmu";
  40
  41         if ((!oh_num) || (oh_num > 3))
  42                 return -EINVAL;
  43
  44         for (i = 0; i < oh_num; i++) {
  45                 oh[i] = omap_hwmod_lookup(oh_names[i]);
  46                 if (!oh[i]) {
  47                         pr_err("Could not look up %s hwmod\n", oh_names[i]);
  48                         return -ENODEV;
  49                 }
  50         }
  51
  52         omap_pmu_dev = omap_device_build_ss(dev_name, -1, oh, oh_num, NULL, 0,
  53                                             NULL, 0, 0);
  54         WARN(IS_ERR(omap_pmu_dev), "Can't build omap_device for %s.\n",
  55              dev_name);
  56
  57         if (IS_ERR(omap_pmu_dev))
  58                 return PTR_ERR(omap_pmu_dev);
  59
  60         pm_runtime_enable(&omap_pmu_dev->dev);
  61
  62         return 0;
  63 }
  64
  65 static int __init omap_init_pmu(void)
  66 {
  67         unsigned oh_num;
  68         char **oh_names;
  69
  70         /*
  71          * To create an ARM-PMU device the following HWMODs
  72          * are required for the various OMAP2+ devices.
  73          *
  74          * OMAP24xx:    mpu
  75          * OMAP3xxx:    mpu, debugss
  76          * OMAP4430:    l3_main_3, l3_instr, debugss
  77          * OMAP4460/70: mpu, debugss
  78          */
  79         if (cpu_is_omap443x()) {
  80                 oh_num = ARRAY_SIZE(omap4430_pmu_oh_names);
  81                 oh_names = omap4430_pmu_oh_names;
  82                 /* XXX Remove the next two lines when CTI driver available */
  83                 pr_info("ARM PMU: not yet supported on OMAP4430 due to missing CTI driver\n");
  84                 return 0;
  85         } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
  86                 oh_num = ARRAY_SIZE(omap3_pmu_oh_names);
  87                 oh_names = omap3_pmu_oh_names;
  88         } else {
  89                 oh_num = ARRAY_SIZE(omap2_pmu_oh_names);
  90                 oh_names = omap2_pmu_oh_names;
  91         }
  92
  93         return omap2_init_pmu(oh_num, oh_names);
  94 }
  95 subsys_initcall(omap_init_pmu);