ARM: cpu topology: Add debugfs interface for cpu_power

[cmplus.git] / arch / arm / mach-omap2 / voltage.c

/*
 * OMAP3/OMAP4 Voltage Management Routines
 *
 * Author: Thara Gopinath       <thara@ti.com>
 *
 * Copyright (C) 2007 Texas Instruments, Inc.
 * Rajendra Nayak <rnayak@ti.com>
 * Lesly A M <x0080970@ti.com>
 *
 * Copyright (C) 2008, 2011 Nokia Corporation
 * Kalle Jokiniemi
 * Paul Walmsley
 *
 * Copyright (C) 2010 Texas Instruments, Inc.
 * Thara Gopinath <thara@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/debugfs.h>
#include <linux/slab.h>

#include <plat/common.h>

#include "prm-regbits-34xx.h"
#include "prm-regbits-44xx.h"
#include "prm44xx.h"
#include "prcm44xx.h"
#include "prminst44xx.h"
#include "control.h"

#include "voltage.h"
#include "powerdomain.h"

#include "vc.h"
#include "vp.h"

static LIST_HEAD(voltdm_list);

static int __init _config_common_vdd_data(struct voltagedomain *voltdm)
{
        struct clk *sys_ck;

        /*
         * Sys clk rate is require to calculate vp timeout value and
         * smpswaittimemin and smpswaittimemax.
         */
        sys_ck = clk_get(NULL, voltdm->sys_clk.name);
        if (IS_ERR(sys_ck)) {
                pr_warning("%s: Could not get the sys clk to calculate"
                        "various vdd_%s params\n", __func__, voltdm->name);
                return -EINVAL;
        }
        voltdm->sys_clk.rate = clk_get_rate(sys_ck);
        WARN_ON(!voltdm->sys_clk.rate);

        /* Generic voltage parameters */
        voltdm->scale = omap_vp_forceupdate_scale;

        return 0;
}

static int __init omap_vdd_data_configure(struct voltagedomain *voltdm)
{
        int ret = -EINVAL;

        if (!voltdm->pmic) {
                pr_err("%s: PMIC info requried to configure vdd_%s not"
                        "populated.Hence cannot initialize vdd_%s\n",
                        __func__, voltdm->name, voltdm->name);
                goto ovdc_out;
        }

        if (IS_ERR_VALUE(_config_common_vdd_data(voltdm)))
                goto ovdc_out;

        ret = 0;

ovdc_out:
        return ret;
}

/* Public functions */
/**
 * omap_voltage_get_curr_vdata() - Gets the current voltage data
 * @voltdm:     pointer to the VDD for which current voltage info is needed
 *
 * API to get the current voltage data pointer for a VDD, returns NULL on error
 */
struct omap_volt_data *omap_voltage_get_curr_vdata(struct voltagedomain *voltdm)
{
        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return NULL;
        }

        return voltdm->curr_volt;
}

/**
 * voltdm_scale() - API to scale voltage of a particular voltage domain.
 * @voltdm: pointer to the voltage domain which is to be scaled.
 * @target_volt: The target voltage of the voltage domain
 *
 * This API should be called by the kernel to do the voltage scaling
 * for a particular voltage domain during DVFS.
 */
int voltdm_scale(struct voltagedomain *voltdm,
                 struct omap_volt_data *target_v)
{
        int ret = 0;
        struct omap_voltage_notifier notify;
        unsigned long target_volt = omap_get_operation_voltage(target_v);

        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return -EINVAL;
        }

        if (!voltdm->scale) {
                pr_err("%s: No voltage scale API registered for vdd_%s\n",
                        __func__, voltdm->name);
                return -ENODATA;
        }

        notify.voltdm = voltdm;
        notify.target_volt = target_volt;

        srcu_notifier_call_chain(&voltdm->change_notify_list,
                        OMAP_VOLTAGE_PRECHANGE,
                        (void *)&notify);

        ret = voltdm->scale(voltdm, target_v);
        if (ret)
                pr_err("%s: voltage scale failed for vdd%s: %d\n",
                        __func__, voltdm->name, ret);

        notify.op_result = ret;
        srcu_notifier_call_chain(&voltdm->change_notify_list,
                        OMAP_VOLTAGE_POSTCHANGE,
                        (void *)&notify);

        return ret;
}

/**
 * voltdm_reset() - Resets the voltage of a particular voltage domain
 *                  to that of the current OPP.
 * @voltdm: pointer to the voltage domain whose voltage is to be reset.
 *
 * This API finds out the correct voltage the voltage domain is supposed
 * to be at and resets the voltage to that level. Should be used especially
 * while disabling any voltage compensation modules.
 *
 * NOTE: appropriate locks should be held for mutual exclusivity.
 */
void voltdm_reset(struct voltagedomain *voltdm)
{
        struct omap_volt_data *target_volt;

        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return;
        }

        target_volt = omap_voltage_get_curr_vdata(voltdm);
        if (!target_volt) {
                pr_err("%s: unable to find current voltage for vdd_%s\n",
                        __func__, voltdm->name);
                return;
        }

        voltdm_scale(voltdm, target_volt);
}

/**
 * omap_voltage_get_volttable() - API to get the voltage table associated with a
 *                              particular voltage domain.
 * @voltdm:     pointer to the VDD for which the voltage table is required
 * @volt_data:  the voltage table for the particular vdd which is to be
 *              populated by this API
 *
 * This API populates the voltage table associated with a VDD into the
 * passed parameter pointer. Returns the count of distinct voltages
 * supported by this vdd.
 *
 */
void omap_voltage_get_volttable(struct voltagedomain *voltdm,
                struct omap_volt_data **volt_data)
{
        struct omap_vdd_info *vdd;

        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return;
        }

        vdd = voltdm->vdd;

        *volt_data = vdd->volt_data;
}

/**
 * omap_voltage_get_voltdata() - API to get the voltage table entry for a
 *                              particular voltage
 * @voltdm:     pointer to the VDD whose voltage table has to be searched
 * @volt:       the voltage to be searched in the voltage table
 *
 * This API searches through the voltage table for the required voltage
 * domain and tries to find a matching entry for the passed voltage volt.
 * If a matching entry is found volt_data is populated with that entry.
 * This API searches only through the non-compensated voltages int the
 * voltage table.
 * Returns pointer to the voltage table entry corresponding to volt on
 * success. Returns -ENODATA if no voltage table exisits for the passed voltage
 * domain or if there is no matching entry.
 */
struct omap_volt_data *omap_voltage_get_voltdata(struct voltagedomain *voltdm,
                unsigned long volt)
{
        struct omap_vdd_info *vdd;
        int i;

        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return ERR_PTR(-EINVAL);
        }

        vdd = voltdm->vdd;

        if (!vdd->volt_data) {
                pr_warning("%s: voltage table does not exist for vdd_%s\n",
                        __func__, voltdm->name);
                return ERR_PTR(-ENODATA);
        }

        for (i = 0; vdd->volt_data[i].volt_nominal != 0; i++) {
                if (vdd->volt_data[i].volt_nominal == volt)
                        return &vdd->volt_data[i];
        }

        pr_notice("%s: Unable to match the current voltage %lu with the voltage"
                "table for vdd_%s\n", __func__, volt, voltdm->name);

        return ERR_PTR(-ENODATA);
}

/**
 * omap_voltage_register_pmic() - API to register PMIC specific data
 * @voltdm:     pointer to the VDD for which the PMIC specific data is
 *              to be registered
 * @pmic:       the structure containing pmic info
 *
 * This API is to be called by the SOC/PMIC file to specify the
 * pmic specific info as present in omap_voltdm_pmic structure.
 */
int omap_voltage_register_pmic(struct voltagedomain *voltdm,
                               struct omap_voltdm_pmic *pmic)
{
        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return -EINVAL;
        }

        voltdm->pmic = pmic;

        return 0;
}

/**
 * omap_change_voltscale_method() - API to change the voltage scaling method.
 * @voltdm:     pointer to the VDD whose voltage scaling method
 *              has to be changed.
 * @voltscale_method:   the method to be used for voltage scaling.
 *
 * This API can be used by the board files to change the method of voltage
 * scaling between vpforceupdate and vcbypass. The parameter values are
 * defined in voltage.h
 */
void omap_change_voltscale_method(struct voltagedomain *voltdm,
                                  int voltscale_method)
{
        if (!voltdm || IS_ERR(voltdm)) {
                pr_warning("%s: VDD specified does not exist!\n", __func__);
                return;
        }

        switch (voltscale_method) {
        case VOLTSCALE_VPFORCEUPDATE:
                voltdm->scale = omap_vp_forceupdate_scale;
                return;
        case VOLTSCALE_VCBYPASS:
                voltdm->scale = omap_vc_bypass_scale_voltage;
                return;
        default:
                pr_warning("%s: Trying to change the method of voltage scaling"
                        "to an unsupported one!\n", __func__);
        }
}

/* Voltage debugfs support */
static int vp_volt_debug_get(void *data, u64 *val)
{
        struct voltagedomain *voltdm = (struct voltagedomain *)data;

        if (!voltdm) {
                pr_warning("Wrong paramater passed\n");
                return -EINVAL;
        }
        *val = omap_vp_get_curr_volt(voltdm);

        return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(vp_volt_debug_fops, vp_volt_debug_get, NULL, "%llu\n");

static int dyn_volt_debug_get(void *data, u64 *val)
{
        struct voltagedomain *voltdm = (struct voltagedomain *)data;
        struct omap_volt_data *volt_data;

        if (!voltdm) {
                pr_warning("%s: Wrong paramater passed\n", __func__);
                return -EINVAL;
        }

        volt_data = omap_voltage_get_curr_vdata(voltdm);
        if (IS_ERR_OR_NULL(volt_data)) {
                pr_warning("%s: No voltage/domain?\n", __func__);
                return -ENODEV;
        }

        *val = volt_data->volt_dynamic_nominal;

        return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(dyn_volt_debug_fops, dyn_volt_debug_get, NULL,
                                                                "%llu\n");

static int calib_volt_debug_get(void *data, u64 *val)
{
        struct voltagedomain *voltdm = (struct voltagedomain *)data;
        struct omap_volt_data *volt_data;

        if (!voltdm) {
                pr_warning("%s: Wrong paramater passed\n", __func__);
                return -EINVAL;
        }

        volt_data = omap_voltage_get_curr_vdata(voltdm);
        if (IS_ERR_OR_NULL(volt_data)) {
                pr_warning("%s: No voltage/domain?\n", __func__);
                return -ENODEV;
        }

        *val = volt_data->volt_calibrated;

        return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(calib_volt_debug_fops, calib_volt_debug_get, NULL,
                                                                "%llu\n");
static int margin_volt_debug_get(void *data, u64 *val)
{
        struct voltagedomain *voltdm = (struct voltagedomain *) data;
        struct omap_volt_data *vdata;

        if (!voltdm) {
                pr_warning("%s: Wrong parameter passed\n", __func__);
                return -EINVAL;
        }

        vdata = omap_voltage_get_curr_vdata(voltdm);
        if (IS_ERR_OR_NULL(vdata)) {
                pr_warning("%s: unable to get volt for vdd_%s\n",
                           __func__, voltdm->name);
                return -ENODEV;
        }
        *val = vdata->volt_margin;

        return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(margin_volt_debug_fops, margin_volt_debug_get, NULL,
                                                                "%llu\n");

static int nom_volt_debug_get(void *data, u64 *val)
{
        struct voltagedomain *voltdm = (struct voltagedomain *) data;
        struct omap_volt_data *vdata;

        if (!voltdm) {
                pr_warning("Wrong paramater passed\n");
                return -EINVAL;
        }

        vdata = omap_voltage_get_curr_vdata(voltdm);
        if (IS_ERR_OR_NULL(vdata)) {
                pr_warning("%s: unable to get volt for vdd_%s\n",
                           __func__, voltdm->name);
                return -ENODEV;
        }
        *val = vdata->volt_nominal;

        return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(nom_volt_debug_fops, nom_volt_debug_get, NULL,
                                                                "%llu\n");

static void __init voltdm_debugfs_init(struct dentry *voltage_dir,
                                        struct voltagedomain *voltdm)
{
        char *name;

        name = kasprintf(GFP_KERNEL, "vdd_%s", voltdm->name);
        if (!name) {
                pr_warning("%s:vdd_%s: no mem for debugfs\n", __func__,
                                voltdm->name);
                return;
        }

        voltdm->debug_dir = debugfs_create_dir(name, voltage_dir);
        kfree(name);
        if (IS_ERR_OR_NULL(voltdm->debug_dir)) {
                pr_warning("%s: Unable to create debugfs directory for"
                        " vdd_%s\n", __func__, voltdm->name);
                voltdm->debug_dir = NULL;
                return;
        }

        (void) debugfs_create_file("curr_vp_volt", S_IRUGO, voltdm->debug_dir,
                                (void *) voltdm, &vp_volt_debug_fops);
        (void) debugfs_create_file("curr_nominal_volt", S_IRUGO,
                                voltdm->debug_dir, (void *) voltdm,
                                &nom_volt_debug_fops);
        (void) debugfs_create_file("curr_dyn_nominal_volt", S_IRUGO,
                                voltdm->debug_dir, (void *) voltdm,
                                &dyn_volt_debug_fops);
        (void) debugfs_create_file("curr_calibrated_volt", S_IRUGO,
                                voltdm->debug_dir, (void *) voltdm,
                                &calib_volt_debug_fops);
        (void) debugfs_create_file("curr_margin_volt", S_IRUGO,
                                voltdm->debug_dir, (void *) voltdm,
                                &margin_volt_debug_fops);
}

/**
 * omap_voltage_late_init() - Init the various voltage parameters
 *
 * This API is to be called in the later stages of the
 * system boot to init the voltage controller and
 * voltage processors.
 */
int __init omap_voltage_late_init(void)
{
        struct voltagedomain *voltdm;
        struct dentry *voltage_dir;

        if (list_empty(&voltdm_list)) {
                pr_err("%s: Voltage driver support not added\n",
                        __func__);
                return -EINVAL;
        }

        voltage_dir = debugfs_create_dir("voltage", NULL);

        list_for_each_entry(voltdm, &voltdm_list, node) {
                if (!voltdm->scalable)
                        continue;

                if (voltdm->vdd) {
                        if (omap_vdd_data_configure(voltdm))
                                continue;
                        omap_vp_init(voltdm);
                }

                if (voltdm->vc)
                        omap_vc_init_channel(voltdm);

                if (voltdm->abb)
                        omap_ldo_abb_init(voltdm);

                if (voltage_dir)
                        voltdm_debugfs_init(voltage_dir, voltdm);

                srcu_init_notifier_head(&voltdm->change_notify_list);
        }

        return 0;
}

static struct voltagedomain *_voltdm_lookup(const char *name)
{
        struct voltagedomain *voltdm, *temp_voltdm;

        voltdm = NULL;

        list_for_each_entry(temp_voltdm, &voltdm_list, node) {
                if (!strcmp(name, temp_voltdm->name)) {
                        voltdm = temp_voltdm;
                        break;
                }
        }

        return voltdm;
}

/**
 * omap_voltage_calib_reset() - reset the calibrated voltage entries
 * @voltdm: voltage domain to reset the entries for
 *
 * when the calibrated entries are no longer valid, this api allows
 * the calibrated voltages to be reset.
 *
 * NOTE: Appropriate locks must be held by calling path to ensure mutual
 * exclusivity
 */
int omap_voltage_calib_reset(struct voltagedomain *voltdm)
{
        struct omap_volt_data *volt_data;

        if (!voltdm) {
                pr_warning("%s: voltdm NULL!\n", __func__);
                return -EINVAL;
        }

        volt_data = voltdm->vdd->volt_data;

        /* reset the calibrated voltages as 0 */
        while (volt_data->volt_nominal) {
                volt_data->volt_calibrated = 0;
                volt_data++;
        }
        return 0;
}

/**
 * voltdm_add_pwrdm - add a powerdomain to a voltagedomain
 * @voltdm: struct voltagedomain * to add the powerdomain to
 * @pwrdm: struct powerdomain * to associate with a voltagedomain
 *
 * Associate the powerdomain @pwrdm with a voltagedomain @voltdm.  This
 * enables the use of voltdm_for_each_pwrdm().  Returns -EINVAL if
 * presented with invalid pointers; -ENOMEM if memory could not be allocated;
 * or 0 upon success.
 */
int voltdm_add_pwrdm(struct voltagedomain *voltdm, struct powerdomain *pwrdm)
{
        if (!voltdm || !pwrdm)
                return -EINVAL;

        pr_debug("voltagedomain: associating powerdomain %s with voltagedomain "
                 "%s\n", pwrdm->name, voltdm->name);

        list_add(&pwrdm->voltdm_node, &voltdm->pwrdm_list);

        return 0;
}

/**
 * voltdm_for_each_pwrdm - call function for each pwrdm in a voltdm
 * @voltdm: struct voltagedomain * to iterate over
 * @fn: callback function *
 *
 * Call the supplied function @fn for each powerdomain in the
 * voltagedomain @voltdm.  Returns -EINVAL if presented with invalid
 * pointers; or passes along the last return value of the callback
 * function, which should be 0 for success or anything else to
 * indicate failure.
 */
int voltdm_for_each_pwrdm(struct voltagedomain *voltdm,
                          int (*fn)(struct voltagedomain *voltdm,
                                    struct powerdomain *pwrdm))
{
        struct powerdomain *pwrdm;
        int ret = 0;

        if (!fn)
                return -EINVAL;

        list_for_each_entry(pwrdm, &voltdm->pwrdm_list, voltdm_node)
                ret = (*fn)(voltdm, pwrdm);

        return ret;
}

/**
 * voltdm_for_each - call function on each registered voltagedomain
 * @fn: callback function *
 *
 * Call the supplied function @fn for each registered voltagedomain.
 * The callback function @fn can return anything but 0 to bail out
 * early from the iterator.  Returns the last return value of the
 * callback function, which should be 0 for success or anything else
 * to indicate failure; or -EINVAL if the function pointer is null.
 */
int voltdm_for_each(int (*fn)(struct voltagedomain *voltdm, void *user),
                    void *user)
{
        struct voltagedomain *temp_voltdm;
        int ret = 0;

        if (!fn)
                return -EINVAL;

        list_for_each_entry(temp_voltdm, &voltdm_list, node) {
                ret = (*fn)(temp_voltdm, user);
                if (ret)
                        break;
        }

        return ret;
}

static int _voltdm_register(struct voltagedomain *voltdm)
{
        if (!voltdm || !voltdm->name)
                return -EINVAL;

        INIT_LIST_HEAD(&voltdm->pwrdm_list);
        list_add(&voltdm->node, &voltdm_list);

        pr_debug("voltagedomain: registered %s\n", voltdm->name);

        return 0;
}

/**
 * voltdm_lookup - look up a voltagedomain by name, return a pointer
 * @name: name of voltagedomain
 *
 * Find a registered voltagedomain by its name @name.  Returns a pointer
 * to the struct voltagedomain if found, or NULL otherwise.
 */
struct voltagedomain *voltdm_lookup(const char *name)
{
        struct voltagedomain *voltdm ;

        if (!name)
                return NULL;

        voltdm = _voltdm_lookup(name);

        return voltdm;
}

/**
 * voltdm_init - set up the voltagedomain layer
 * @voltdm_list: array of struct voltagedomain pointers to register
 *
 * Loop through the array of voltagedomains @voltdm_list, registering all
 * that are available on the current CPU. If voltdm_list is supplied
 * and not null, all of the referenced voltagedomains will be
 * registered.  No return value.
 */
void voltdm_init(struct voltagedomain **voltdms)
{
        struct voltagedomain **v;

        if (voltdms) {
                for (v = voltdms; *v; v++)
                        _voltdm_register(*v);
        }
}