pmu.c

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/*
 * OMAP2 ARM Performance Monitoring Unit (PMU) Support
 *
 * Copyright (C) 2012 Texas Instruments, Inc.
 *
 * Contacts:
 * Jon Hunter <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */
#include <linux/pm_runtime.h>

#include <asm/pmu.h>

#include <plat/omap_hwmod.h>
#include <plat/omap_device.h>

static char *omap2_pmu_oh_names[] = {"mpu"};
static char *omap3_pmu_oh_names[] = {"mpu", "debugss"};
static char *omap4430_pmu_oh_names[] = {"l3_main_3", "l3_instr", "debugss"};
static struct platform_device *omap_pmu_dev;

static int __init omap2_init_pmu(unsigned oh_num, char *oh_names[])
{
    int i;
    struct omap_hwmod *oh[3];
    char *dev_name = "arm-pmu";

    if ((!oh_num) || (oh_num > 3))
        return -EINVAL;

    for (i = 0; i < oh_num; i++) {
        oh[i] = omap_hwmod_lookup(oh_names[i]);
        if (!oh[i]) {
            pr_err("Could not look up %s hwmod\n", oh_names[i]);
            return -ENODEV;
        }
    }

    omap_pmu_dev = omap_device_build_ss(dev_name, -1, oh, oh_num, NULL, 0,
                        NULL, 0, 0);
    WARN(IS_ERR(omap_pmu_dev), "Can't build omap_device for %s.\n",
         dev_name);

    if (IS_ERR(omap_pmu_dev))
        return PTR_ERR(omap_pmu_dev);

    pm_runtime_enable(&omap_pmu_dev->dev);

    return 0;
}

static int __init omap_init_pmu(void)
{
    unsigned oh_num;
    char **oh_names;

    /*
     * To create an ARM-PMU device the following HWMODs
     * are required for the various OMAP2+ devices.
     *
     * OMAP24xx:    mpu
     * OMAP3xxx:    mpu, debugss
     * OMAP4430:    l3_main_3, l3_instr, debugss
     * OMAP4460/70: mpu, debugss
     */
    if (cpu_is_omap443x()) {
        oh_num = ARRAY_SIZE(omap4430_pmu_oh_names);
        oh_names = omap4430_pmu_oh_names;
        /* XXX Remove the next two lines when CTI driver available */
        pr_info("ARM PMU: not yet supported on OMAP4430 due to missing CTI driver\n");
        return 0;
    } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
        oh_num = ARRAY_SIZE(omap3_pmu_oh_names);
        oh_names = omap3_pmu_oh_names;
    } else {
        oh_num = ARRAY_SIZE(omap2_pmu_oh_names);
        oh_names = omap2_pmu_oh_names;
    }

    return omap2_init_pmu(oh_num, oh_names);
}
subsys_initcall(omap_init_pmu);