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Release 4.14 drivers/cpufreq/sti-cpufreq.c

Directory: drivers/cpufreq
/*
 * Match running platform with pre-defined OPP values for CPUFreq
 *
 * Author: Ajit Pal Singh <ajitpal.singh@st.com>
 *         Lee Jones <lee.jones@linaro.org>
 *
 * Copyright (C) 2015 STMicroelectronics (R&D) Limited
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the version 2 of the GNU General Public License as
 * published by the Free Software Foundation
 */

#include <linux/cpu.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pm_opp.h>
#include <linux/regmap.h>


#define VERSION_ELEMENTS	3

#define MAX_PCODE_NAME_LEN	7


#define VERSION_SHIFT		28

#define HW_INFO_INDEX		1

#define MAJOR_ID_INDEX		1

#define MINOR_ID_INDEX		2

/*
 * Only match on "suitable for ALL versions" entries
 *
 * This will be used with the BIT() macro.  It sets the
 * top bit of a 32bit value and is equal to 0x80000000.
 */

#define DEFAULT_VERSION		31

enum {
	
PCODE = 0,
	
SUBSTRATE,
	
DVFS_MAX_REGFIELDS,
};

/**
 * ST CPUFreq Driver Data
 *
 * @cpu_node            CPU's OF node
 * @syscfg_eng          Engineering Syscon register map
 * @regmap              Syscon register map
 */

static struct sti_cpufreq_ddata {
	
struct device *cpu;
	
struct regmap *syscfg_eng;
	
struct regmap *syscfg;

} ddata;


static int sti_cpufreq_fetch_major(void) { struct device_node *np = ddata.cpu->of_node; struct device *dev = ddata.cpu; unsigned int major_offset; unsigned int socid; int ret; ret = of_property_read_u32_index(np, "st,syscfg", MAJOR_ID_INDEX, &major_offset); if (ret) { dev_err(dev, "No major number offset provided in %pOF [%d]\n", np, ret); return ret; } ret = regmap_read(ddata.syscfg, major_offset, &socid); if (ret) { dev_err(dev, "Failed to read major number from syscon [%d]\n", ret); return ret; } return ((socid >> VERSION_SHIFT) & 0xf) + 1; }

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Lee Jones11799.15%150.00%
Rob Herring10.85%150.00%
Total118100.00%2100.00%


static int sti_cpufreq_fetch_minor(void) { struct device *dev = ddata.cpu; struct device_node *np = dev->of_node; unsigned int minor_offset; unsigned int minid; int ret; ret = of_property_read_u32_index(np, "st,syscfg-eng", MINOR_ID_INDEX, &minor_offset); if (ret) { dev_err(dev, "No minor number offset provided %pOF [%d]\n", np, ret); return ret; } ret = regmap_read(ddata.syscfg_eng, minor_offset, &minid); if (ret) { dev_err(dev, "Failed to read the minor number from syscon [%d]\n", ret); return ret; } return minid & 0xf; }

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Lee Jones10799.07%150.00%
Rob Herring10.93%150.00%
Total108100.00%2100.00%


static int sti_cpufreq_fetch_regmap_field(const struct reg_field *reg_fields, int hw_info_offset, int field) { struct regmap_field *regmap_field; struct reg_field reg_field = reg_fields[field]; struct device *dev = ddata.cpu; unsigned int value; int ret; reg_field.reg = hw_info_offset; regmap_field = devm_regmap_field_alloc(dev, ddata.syscfg_eng, reg_field); if (IS_ERR(regmap_field)) { dev_err(dev, "Failed to allocate reg field\n"); return PTR_ERR(regmap_field); } ret = regmap_field_read(regmap_field, &value); if (ret) { dev_err(dev, "Failed to read %s code\n", field ? "SUBSTRATE" : "PCODE"); return ret; } return value; }

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Lee Jones124100.00%1100.00%
Total124100.00%1100.00%

static const struct reg_field sti_stih407_dvfs_regfields[DVFS_MAX_REGFIELDS] = { [PCODE] = REG_FIELD(0, 16, 19), [SUBSTRATE] = REG_FIELD(0, 0, 2), };
static const struct reg_field *sti_cpufreq_match(void) { if (of_machine_is_compatible("st,stih407") || of_machine_is_compatible("st,stih410")) return sti_stih407_dvfs_regfields; return NULL; }

Contributors

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Lee Jones29100.00%1100.00%
Total29100.00%1100.00%


static int sti_cpufreq_set_opp_info(void) { struct device *dev = ddata.cpu; struct device_node *np = dev->of_node; const struct reg_field *reg_fields; unsigned int hw_info_offset; unsigned int version[VERSION_ELEMENTS]; int pcode, substrate, major, minor; int ret; char name[MAX_PCODE_NAME_LEN]; struct opp_table *opp_table; reg_fields = sti_cpufreq_match(); if (!reg_fields) { dev_err(dev, "This SoC doesn't support voltage scaling\n"); return -ENODEV; } ret = of_property_read_u32_index(np, "st,syscfg-eng", HW_INFO_INDEX, &hw_info_offset); if (ret) { dev_warn(dev, "Failed to read HW info offset from DT\n"); substrate = DEFAULT_VERSION; pcode = 0; goto use_defaults; } pcode = sti_cpufreq_fetch_regmap_field(reg_fields, hw_info_offset, PCODE); if (pcode < 0) { dev_warn(dev, "Failed to obtain process code\n"); /* Use default pcode */ pcode = 0; } substrate = sti_cpufreq_fetch_regmap_field(reg_fields, hw_info_offset, SUBSTRATE); if (substrate) { dev_warn(dev, "Failed to obtain substrate code\n"); /* Use default substrate */ substrate = DEFAULT_VERSION; } use_defaults: major = sti_cpufreq_fetch_major(); if (major < 0) { dev_err(dev, "Failed to obtain major version\n"); /* Use default major number */ major = DEFAULT_VERSION; } minor = sti_cpufreq_fetch_minor(); if (minor < 0) { dev_err(dev, "Failed to obtain minor version\n"); /* Use default minor number */ minor = DEFAULT_VERSION; } snprintf(name, MAX_PCODE_NAME_LEN, "pcode%d", pcode); opp_table = dev_pm_opp_set_prop_name(dev, name); if (IS_ERR(opp_table)) { dev_err(dev, "Failed to set prop name\n"); return PTR_ERR(opp_table); } version[0] = BIT(major); version[1] = BIT(minor); version[2] = BIT(substrate); opp_table = dev_pm_opp_set_supported_hw(dev, version, VERSION_ELEMENTS); if (IS_ERR(opp_table)) { dev_err(dev, "Failed to set supported hardware\n"); return PTR_ERR(opp_table); } dev_dbg(dev, "pcode: %d major: %d minor: %d substrate: %d\n", pcode, major, minor, substrate); dev_dbg(dev, "version[0]: %x version[1]: %x version[2]: %x\n", version[0], version[1], version[2]); return 0; }

Contributors

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Lee Jones36093.75%133.33%
Viresh Kumar235.99%133.33%
Colin Ian King10.26%133.33%
Total384100.00%3100.00%


static int sti_cpufreq_fetch_syscon_registers(void) { struct device *dev = ddata.cpu; struct device_node *np = dev->of_node; ddata.syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg"); if (IS_ERR(ddata.syscfg)) { dev_err(dev, "\"st,syscfg\" not supplied\n"); return PTR_ERR(ddata.syscfg); } ddata.syscfg_eng = syscon_regmap_lookup_by_phandle(np, "st,syscfg-eng"); if (IS_ERR(ddata.syscfg_eng)) { dev_err(dev, "\"st,syscfg-eng\" not supplied\n"); return PTR_ERR(ddata.syscfg_eng); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Lee Jones10299.03%150.00%
Stephen Boyd10.97%150.00%
Total103100.00%2100.00%


static int sti_cpufreq_init(void) { int ret; if ((!of_machine_is_compatible("st,stih407")) && (!of_machine_is_compatible("st,stih410"))) return -ENODEV; ddata.cpu = get_cpu_device(0); if (!ddata.cpu) { dev_err(ddata.cpu, "Failed to get device for CPU0\n"); goto skip_voltage_scaling; } if (!of_get_property(ddata.cpu->of_node, "operating-points-v2", NULL)) { dev_err(ddata.cpu, "OPP-v2 not supported\n"); goto skip_voltage_scaling; } ret = sti_cpufreq_fetch_syscon_registers(); if (ret) goto skip_voltage_scaling; ret = sti_cpufreq_set_opp_info(); if (!ret) goto register_cpufreq_dt; skip_voltage_scaling: dev_err(ddata.cpu, "Not doing voltage scaling\n"); register_cpufreq_dt: platform_device_register_simple("cpufreq-dt", -1, NULL, 0); return 0; }

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Lee Jones12384.25%133.33%
Sudeep Holla2215.07%133.33%
Stephen Boyd10.68%133.33%
Total146100.00%3100.00%

module_init(sti_cpufreq_init); MODULE_DESCRIPTION("STMicroelectronics CPUFreq/OPP driver"); MODULE_AUTHOR("Ajitpal Singh <ajitpal.singh@st.com>"); MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Lee Jones111295.70%116.67%
Viresh Kumar231.98%116.67%
Sudeep Holla221.89%116.67%
Rob Herring20.17%116.67%
Stephen Boyd20.17%116.67%
Colin Ian King10.09%116.67%
Total1162100.00%6100.00%
Directory: drivers/cpufreq
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