// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2002,2003 Intrinsyc Software
*
* History:
* 31-Jul-2002 : Initial version [FB]
* 29-Jan-2003 : added PXA255 support [FB]
* 20-Apr-2003 : ported to v2.5 (Dustin McIntire, Sensoria Corp.)
*
* Note:
* This driver may change the memory bus clock rate, but will not do any
* platform specific access timing changes... for example if you have flash
* memory connected to CS0, you will need to register a platform specific
* notifier which will adjust the memory access strobes to maintain a
* minimum strobe width.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/err.h>
#include <linux/regulator/consumer.h>
#include <linux/soc/pxa/cpu.h>
#include <linux/io.h>
#ifdef DEBUG
static unsigned int freq_debug;
module_param(freq_debug, uint, 0);
MODULE_PARM_DESC(freq_debug, "Set the debug messages to on=1/off=0");
#else
#define freq_debug 0
#endif
static struct regulator *vcc_core;
static unsigned int pxa27x_maxfreq;
module_param(pxa27x_maxfreq, uint, 0);
MODULE_PARM_DESC(pxa27x_maxfreq, "Set the pxa27x maxfreq in MHz"
"(typically 624=>pxa270, 416=>pxa271, 520=>pxa272)");
struct pxa_cpufreq_data {
struct clk *clk_core;
};
static struct pxa_cpufreq_data pxa_cpufreq_data;
struct pxa_freqs {
unsigned int khz;
int vmin;
int vmax;
};
/*
* PXA255 definitions
*/
static const struct pxa_freqs pxa255_run_freqs[] =
{
/* CPU MEMBUS run turbo PXbus SDRAM */
{ 99500, -1, -1}, /* 99, 99, 50, 50 */
{132700, -1, -1}, /* 133, 133, 66, 66 */
{199100, -1, -1}, /* 199, 199, 99, 99 */
{265400, -1, -1}, /* 265, 265, 133, 66 */
{331800, -1, -1}, /* 331, 331, 166, 83 */
{398100, -1, -1}, /* 398, 398, 196, 99 */
};
/* Use the turbo mode frequencies for the CPUFREQ_POLICY_POWERSAVE policy */
static const struct pxa_freqs pxa255_turbo_freqs[] =
{
/* CPU run turbo PXbus SDRAM */
{ 99500, -1, -1}, /* 99, 99, 50, 50 */
{199100, -1, -1}, /* 99, 199, 50, 99 */
{298500, -1, -1}, /* 99, 287, 50, 99 */
{298600, -1, -1}, /* 199, 287, 99, 99 */
{398100, -1, -1}, /* 199, 398, 99, 99 */
};
#define NUM_PXA25x_RUN_FREQS ARRAY_SIZE(pxa255_run_freqs)
#define NUM_PXA25x_TURBO_FREQS ARRAY_SIZE(pxa255_turbo_freqs)
static struct cpufreq_frequency_table
pxa255_run_freq_table[NUM_PXA25x_RUN_FREQS+1];
static struct cpufreq_frequency_table
pxa255_turbo_freq_table[NUM_PXA25x_TURBO_FREQS+1];
static unsigned int pxa255_turbo_table;
module_param(pxa255_turbo_table, uint, 0);
MODULE_PARM_DESC(pxa255_turbo_table, "Selects the frequency table (0 = run table, !0 = turbo table)");
static struct pxa_freqs pxa27x_freqs[] = {
{104000, 900000, 1705000 },
{156000, 1000000, 1705000 },
{208000, 1180000, 1705000 },
{312000, 1250000, 1705000 },
{416000, 1350000, 1705000 },
{520000, 1450000, 1705000 },
{624000, 1550000, 1705000 }
};
#define NUM_PXA27x_FREQS ARRAY_SIZE(pxa27x_freqs)
static struct cpufreq_frequency_table
pxa27x_freq_table[NUM_PXA27x_FREQS+1];
#ifdef CONFIG_REGULATOR
static int pxa_cpufreq_change_voltage(const struct pxa_freqs *pxa_freq)
{
int ret = 0;
int vmin, vmax;
if (!cpu_is_pxa27x())
return 0;
vmin = pxa_freq->vmin;
vmax = pxa_freq->vmax;
if ((vmin == -1) || (vmax == -1))
return 0;
ret = regulator_set_voltage(vcc_core, vmin, vmax);
if (ret)
pr_err("Failed to set vcc_core in [%dmV..%dmV]\n", vmin, vmax);
return ret;
}
static void pxa_cpufreq_init_voltages(void)
{
vcc_core = regulator_get(NULL, "vcc_core");
if (IS_ERR(vcc_core)) {
pr_info("Didn't find vcc_core regulator\n");
vcc_core = NULL;
} else {
pr_info("Found vcc_core regulator\n");
}
}
#else
static int pxa_cpufreq_change_voltage(const struct pxa_freqs *pxa_freq)
{
return 0;
}
static void pxa_cpufreq_init_voltages(void) { }
#endif
static void find_freq_tables(struct cpufreq_frequency_table **freq_table,
const struct pxa_freqs **pxa_freqs)
{
if (cpu_is_pxa25x()) {
if (!pxa255_turbo_table) {
*pxa_freqs = pxa255_run_freqs;
*freq_table = pxa255_run_freq_table;
} else {
*pxa_freqs = pxa255_turbo_freqs;
*freq_table = pxa255_turbo_freq_table;
}
} else if (cpu_is_pxa27x()) {
*pxa_freqs = pxa27x_freqs;
*freq_table = pxa27x_freq_table;
} else {
BUG();
}
}
static void pxa27x_guess_max_freq(void)
{
if (!pxa27x_maxfreq) {
pxa27x_maxfreq = 416000;
pr_info("PXA CPU 27x max frequency not defined (pxa27x_maxfreq), assuming pxa271 with %dkHz maxfreq\n",
pxa27x_maxfreq);
} else {
pxa27x_maxfreq *= 1000;
}
}
static unsigned int pxa_cpufreq_get(unsigned int cpu)
{
struct pxa_cpufreq_data *data = cpufreq_get_driver_data();
return (unsigned int) clk_get_rate(data->clk_core) / 1000;
}
static int pxa_set_target(struct cpufreq_policy *policy, unsigned int idx)
{
struct cpufreq_frequency_table *pxa_freqs_table;
const struct pxa_freqs *pxa_freq_settings;
struct pxa_cpufreq_data *data = cpufreq_get_driver_data();
unsigned int new_freq_cpu;
int ret = 0;
/* Get the current policy */
find_freq_tables(&pxa_freqs_table, &pxa_freq_settings);
new_freq_cpu = pxa_freq_settings[idx].khz;
if (freq_debug)
pr_debug("Changing CPU frequency from %d Mhz to %d Mhz\n",
policy->cur / 1000, new_freq_cpu / 1000);
if (vcc_core && new_freq_cpu > policy->cur) {
ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]);
if (ret)
return ret;
}
clk_set_rate(data->clk_core, new_freq_cpu * 1000);
/*
* Even if voltage setting fails, we don't report it, as the frequency
* change succeeded. The voltage reduction is not a critical failure,
* only power savings will suffer from this.
*
* Note: if the voltage change fails, and a return value is returned, a
* bug is triggered (seems a deadlock). Should anybody find out where,
* the "return 0" should become a "return ret".
*/
if (vcc_core && new_freq_cpu < policy->cur)
ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]);
return 0;
}
static int pxa_cpufreq_init(struct cpufreq_policy *policy)
{
int i;
unsigned int freq;
struct cpufreq_frequency_table *pxa255_freq_table;
const struct pxa_freqs *pxa255_freqs;
/* try to guess pxa27x cpu */
if (cpu_is_pxa27x())
pxa27x_guess_max_freq();
pxa_cpufreq_init_voltages();
/* set default policy and cpuinfo */
policy->cpuinfo.transition_latency = 1000; /* FIXME: 1 ms, assumed */
/* Generate pxa25x the run cpufreq_frequency_table struct */
for (i = 0; i < NUM_PXA25x_RUN_FREQS; i++) {
pxa255_run_freq_table[i].frequency = pxa255_run_freqs[i].khz;
pxa255_run_freq_table[i].driver_data = i;
}
pxa255_run_freq_table[i].frequency = CPUFREQ_TABLE_END;
/* Generate pxa25x the turbo cpufreq_frequency_table struct */
for (i = 0; i < NUM_PXA25x_TURBO_FREQS; i++) {
pxa255_turbo_freq_table[i].frequency =
pxa255_turbo_freqs[i].khz;
pxa255_turbo_freq_table[i].driver_data = i;
}
pxa255_turbo_freq_table[i].frequency = CPUFREQ_TABLE_END;
pxa255_turbo_table = !!pxa255_turbo_table;
/* Generate the pxa27x cpufreq_frequency_table struct */
for (i = 0; i < NUM_PXA27x_FREQS; i++) {
freq = pxa27x_freqs[i].khz;
if (freq > pxa27x_maxfreq)
break;
pxa27x_freq_table[i].frequency = freq;
pxa27x_freq_table[i].driver_data = i;
}
pxa27x_freq_table[i].driver_data = i;
pxa27x_freq_table[i].frequency = CPUFREQ_TABLE_END;
/*
* Set the policy's minimum and maximum frequencies from the tables
* just constructed. This sets cpuinfo.mxx_freq, min and max.
*/
if (cpu_is_pxa25x()) {
find_freq_tables(&pxa255_freq_table, &pxa255_freqs);
pr_info("using %s frequency table\n",
pxa255_turbo_table ? "turbo" : "run");
policy->freq_table = pxa255_freq_table;
}
else if (cpu_is_pxa27x()) {
policy->freq_table = pxa27x_freq_table;
}
pr_info("frequency change support initialized\n");
return 0;
}
static struct cpufreq_driver pxa_cpufreq_driver = {
.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.verify = cpufreq_generic_frequency_table_verify,
.target_index = pxa_set_target,
.init = pxa_cpufreq_init,
.get = pxa_cpufreq_get,
.name = "PXA2xx",
.driver_data = &pxa_cpufreq_data,
};
static int __init pxa_cpu_init(void)
{
int ret = -ENODEV;
pxa_cpufreq_data.clk_core = clk_get_sys(NULL, "core");
if (IS_ERR(pxa_cpufreq_data.clk_core))
return PTR_ERR(pxa_cpufreq_data.clk_core);
if (cpu_is_pxa25x() || cpu_is_pxa27x())
ret = cpufreq_register_driver(&pxa_cpufreq_driver);
return ret;
}
static void __exit pxa_cpu_exit(void)
{
cpufreq_unregister_driver(&pxa_cpufreq_driver);
}
MODULE_AUTHOR("Intrinsyc Software Inc.");
MODULE_DESCRIPTION("CPU frequency changing driver for the PXA architecture");
MODULE_LICENSE("GPL");
module_init(pxa_cpu_init);
module_exit(pxa_cpu_exit);
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