/*
* linux/arch/arm/mach-pxa/cpufreq-pxa3xx.c
*
* Copyright (C) 2008 Marvell International Ltd.
*
* 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/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <mach/pxa3xx-regs.h>
#include "generic.h"
#define HSS_104M (0)
#define HSS_156M (1)
#define HSS_208M (2)
#define HSS_312M (3)
#define SMCFS_78M (0)
#define SMCFS_104M (2)
#define SMCFS_208M (5)
#define SFLFS_104M (0)
#define SFLFS_156M (1)
#define SFLFS_208M (2)
#define SFLFS_312M (3)
#define XSPCLK_156M (0)
#define XSPCLK_NONE (3)
#define DMCFS_26M (0)
#define DMCFS_260M (3)
struct pxa3xx_freq_info {
unsigned int cpufreq_mhz;
unsigned int core_xl : 5;
unsigned int core_xn : 3;
unsigned int hss : 2;
unsigned int dmcfs : 2;
unsigned int smcfs : 3;
unsigned int sflfs : 2;
unsigned int df_clkdiv : 3;
int vcc_core; /* in mV */
int vcc_sram; /* in mV */
};
#define OP(cpufreq, _xl, _xn, _hss, _dmc, _smc, _sfl, _dfi, vcore, vsram) \
{ \
.cpufreq_mhz = cpufreq, \
.core_xl = _xl, \
.core_xn = _xn, \
.hss = HSS_##_hss##M, \
.dmcfs = DMCFS_##_dmc##M, \
.smcfs = SMCFS_##_smc##M, \
.sflfs = SFLFS_##_sfl##M, \
.df_clkdiv = _dfi, \
.vcc_core = vcore, \
.vcc_sram = vsram, \
}
static struct pxa3xx_freq_info pxa300_freqs[] = {
/* CPU XL XN HSS DMEM SMEM SRAM DFI VCC_CORE VCC_SRAM */
OP(104, 8, 1, 104, 260, 78, 104, 3, 1000, 1100), /* 104MHz */
OP(208, 16, 1, 104, 260, 104, 156, 2, 1000, 1100), /* 208MHz */
OP(416, 16, 2, 156, 260, 104, 208, 2, 1100, 1200), /* 416MHz */
OP(624, 24, 2, 208, 260, 208, 312, 3, 1375, 1400), /* 624MHz */
};
static struct pxa3xx_freq_info pxa320_freqs[] = {
/* CPU XL XN HSS DMEM SMEM SRAM DFI VCC_CORE VCC_SRAM */
OP(104, 8, 1, 104, 260, 78, 104, 3, 1000, 1100), /* 104MHz */
OP(208, 16, 1, 104, 260, 104, 156, 2, 1000, 1100), /* 208MHz */
OP(416, 16, 2, 156, 260, 104, 208, 2, 1100, 1200), /* 416MHz */
OP(624, 24, 2, 208, 260, 208, 312, 3, 1375, 1400), /* 624MHz */
OP(806, 31, 2, 208, 260, 208, 312, 3, 1400, 1400), /* 806MHz */
};
static unsigned int pxa3xx_freqs_num;
static struct pxa3xx_freq_info *pxa3xx_freqs;
static struct cpufreq_frequency_table *pxa3xx_freqs_table;
static int setup_freqs_table(struct cpufreq_policy *policy,
struct pxa3xx_freq_info *freqs, int num)
{
struct cpufreq_frequency_table *table;
int i;
table = kzalloc((num + 1) * sizeof(*table), GFP_KERNEL);
if (table == NULL)
return -ENOMEM;
for (i = 0; i < num; i++) {
table[i].index = i;
table[i].frequency = freqs[i].cpufreq_mhz * 1000;
}
table[num].frequency = i;
table[num].frequency = CPUFREQ_TABLE_END;
pxa3xx_freqs = freqs;
pxa3xx_freqs_num = num;
pxa3xx_freqs_table = table;
return cpufreq_frequency_table_cpuinfo(policy, table);
}
static void __update_core_freq(struct pxa3xx_freq_info *info)
{
uint32_t mask = ACCR_XN_MASK | ACCR_XL_MASK;
uint32_t accr = ACCR;
uint32_t xclkcfg;
accr &= ~(ACCR_XN_MASK | ACCR_XL_MASK | ACCR_XSPCLK_MASK);
accr |= ACCR_XN(info->core_xn) | ACCR_XL(info->core_xl);
/* No clock until core PLL is re-locked */
accr |= ACCR_XSPCLK(XSPCLK_NONE);
xclkcfg = (info->core_xn == 2) ? 0x3 : 0x2; /* turbo bit */
ACCR = accr;
__asm__("mcr p14, 0, %0, c6, c0, 0\n" : : "r"(xclkcfg));
while ((ACSR & mask) != (accr & mask))
cpu_relax();
}
static void __update_bus_freq(struct pxa3xx_freq_info *info)
{
uint32_t mask;
uint32_t accr = ACCR;
mask = ACCR_SMCFS_MASK | ACCR_SFLFS_MASK | ACCR_HSS_MASK |
ACCR_DMCFS_MASK;
accr &= ~mask;
accr |= ACCR_SMCFS(info->smcfs) | ACCR_SFLFS(info->sflfs) |
ACCR_HSS(info->hss) | ACCR_DMCFS(info->dmcfs);
ACCR = accr;
while ((ACSR & mask) != (accr & mask))
cpu_relax();
}
static int pxa3xx_cpufreq_verify(struct cpufreq_policy *policy)
{
return cpufreq_frequency_table_verify(policy, pxa3xx_freqs_table);
}
static unsigned int pxa3xx_cpufreq_get(unsigned int cpu)
{
return get_clk_frequency_khz(0);
}
static int pxa3xx_cpufreq_set(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct pxa3xx_freq_info *next;
struct cpufreq_freqs freqs;
unsigned long flags;
int idx;
if (policy->cpu != 0)
return -EINVAL;
/* Lookup the next frequency */
if (cpufreq_frequency_table_target(policy, pxa3xx_freqs_table,
target_freq, relation, &idx))
return -EINVAL;
next = &pxa3xx_freqs[idx];
freqs.old = policy->cur;
freqs.new = next->cpufreq_mhz * 1000;
freqs.cpu = policy->cpu;
pr_debug("CPU frequency from %d MHz to %d MHz%s\n",
freqs.old / 1000, freqs.new / 1000,
(freqs.old == freqs.new) ? " (skipped)" : "");
if (freqs.old == target_freq)
return 0;
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
local_irq_save(flags);
__update_core_freq(next);
__update_bus_freq(next);
local_irq_restore(flags);
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
return 0;
}
static __init int pxa3xx_cpufreq_init(struct cpufreq_policy *policy)
{
int ret = -EINVAL;
/* set default policy and cpuinfo */
policy->cpuinfo.min_freq = 104000;
policy->cpuinfo.max_freq = (cpu_is_pxa320()) ? 806000 : 624000;
policy->cpuinfo.transition_latency = 1000; /* FIXME: 1 ms, assumed */
policy->cur = policy->min = policy->max = get_clk_frequency_khz(0);
if (cpu_is_pxa300() || cpu_is_pxa310())
ret = setup_freqs_table(policy, ARRAY_AND_SIZE(pxa300_freqs));
if (cpu_is_pxa320())
ret = setup_freqs_table(policy, ARRAY_AND_SIZE(pxa320_freqs));
if (ret) {
pr_err("failed to setup frequency table\n");
return ret;
}
pr_info("CPUFREQ support for PXA3xx initialized\n");
return 0;
}
static struct cpufreq_driver pxa3xx_cpufreq_driver = {
.verify = pxa3xx_cpufreq_verify,
.target = pxa3xx_cpufreq_set,
.init = pxa3xx_cpufreq_init,
.get = pxa3xx_cpufreq_get,
.name = "pxa3xx-cpufreq",
};
static int __init cpufreq_init(void)
{
if (cpu_is_pxa3xx())
return cpufreq_register_driver(&pxa3xx_cpufreq_driver);
return 0;
}
module_init(cpufreq_init);
static void __exit cpufreq_exit(void)
{
cpufreq_unregister_driver(&pxa3xx_cpufreq_driver);
}
module_exit(cpufreq_exit);
MODULE_DESCRIPTION("CPU frequency scaling driver for PXA3xx");
MODULE_LICENSE("GPL");
