// SPDX-License-Identifier: GPL-2.0-only
/*
* OMAP3/OMAP4 Voltage Management Routines
*
* Author: Thara Gopinath <[email protected]>
*
* Copyright (C) 2007 Texas Instruments, Inc.
* Rajendra Nayak <[email protected]>
* Lesly A M <[email protected]>
*
* Copyright (C) 2008, 2011 Nokia Corporation
* Kalle Jokiniemi
* Paul Walmsley
*
* Copyright (C) 2010 Texas Instruments, Inc.
* Thara Gopinath <[email protected]>
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include "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);
/* Public functions */
/**
* voltdm_get_voltage() - Gets the current non-auto-compensated voltage
* @voltdm: pointer to the voltdm for which current voltage info is needed
*
* API to get the current non-auto-compensated voltage for a voltage domain.
* Returns 0 in case of error else returns the current voltage.
*/
unsigned long voltdm_get_voltage(struct voltagedomain *voltdm)
{
if (!voltdm || IS_ERR(voltdm)) {
pr_warn("%s: VDD specified does not exist!\n", __func__);
return 0;
}
return voltdm->nominal_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.
*/
static int voltdm_scale(struct voltagedomain *voltdm,
unsigned long target_volt)
{
int ret, i;
unsigned long volt = 0;
if (!voltdm || IS_ERR(voltdm)) {
pr_warn("%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;
}
if (!voltdm->volt_data) {
pr_err("%s: No voltage data defined for vdd_%s\n",
__func__, voltdm->name);
return -ENODATA;
}
/* Adjust voltage to the exact voltage from the OPP table */
for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
if (voltdm->volt_data[i].volt_nominal >= target_volt) {
volt = voltdm->volt_data[i].volt_nominal;
break;
}
}
if (!volt) {
pr_warn("%s: not scaling. OPP voltage for %lu, not found.\n",
__func__, target_volt);
return -EINVAL;
}
ret = voltdm->scale(voltdm, volt);
if (!ret)
voltdm->nominal_volt = volt;
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.
*/
void voltdm_reset(struct voltagedomain *voltdm)
{
unsigned long target_volt;
if (!voltdm || IS_ERR(voltdm)) {
pr_warn("%s: VDD specified does not exist!\n", __func__);
return;
}
target_volt = voltdm_get_voltage(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)
{
if (!voltdm || IS_ERR(voltdm)) {
pr_warn("%s: VDD specified does not exist!\n", __func__);
return;
}
*volt_data = voltdm->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)
{
int i;
if (!voltdm || IS_ERR(voltdm)) {
pr_warn("%s: VDD specified does not exist!\n", __func__);
return ERR_PTR(-EINVAL);
}
if (!voltdm->volt_data) {
pr_warn("%s: voltage table does not exist for vdd_%s\n",
__func__, voltdm->name);
return ERR_PTR(-ENODATA);
}
for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
if (voltdm->volt_data[i].volt_nominal == volt)
return &voltdm->volt_data[i];
}
pr_notice("%s: Unable to match the current voltage with the voltage table for vdd_%s\n",
__func__, 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_warn("%s: VDD specified does not exist!\n", __func__);
return -EINVAL;
}
voltdm->pmic = pmic;
return 0;
}
/**
* 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;
if (list_empty(&voltdm_list)) {
pr_err("%s: Voltage driver support not added\n",
__func__);
return -EINVAL;
}
list_for_each_entry(voltdm, &voltdm_list, node) {
struct clk *sys_ck;
if (!voltdm->scalable)
continue;
sys_ck = clk_get(NULL, voltdm->sys_clk.name);
if (IS_ERR(sys_ck)) {
pr_warn("%s: Could not get sys clk.\n", __func__);
return -EINVAL;
}
voltdm->sys_clk.rate = clk_get_rate(sys_ck);
WARN_ON(!voltdm->sys_clk.rate);
clk_put(sys_ck);
if (voltdm->vc) {
voltdm->scale = omap_vc_bypass_scale;
omap_vc_init_channel(voltdm);
}
if (voltdm->vp) {
voltdm->scale = omap_vp_forceupdate_scale;
omap_vp_init(voltdm);
}
}
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;
}
static int _voltdm_register(struct voltagedomain *voltdm)
{
if (!voltdm || !voltdm->name)
return -EINVAL;
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);
}
}
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