OpenCloudOS-Kernel/drivers/cpufreq/s3c24xx-cpufreq.c

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/*
* Copyright (c) 2006-2008 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* S3C24XX CPU Frequency scaling
*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/cpufreq.h>
#include <linux/cpu.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/sysfs.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <plat/cpu.h>
#include <plat/cpu-freq-core.h>
#include <mach/regs-clock.h>
/* note, cpufreq support deals in kHz, no Hz */
static struct cpufreq_driver s3c24xx_driver;
static struct s3c_cpufreq_config cpu_cur;
static struct s3c_iotimings s3c24xx_iotiming;
static struct cpufreq_frequency_table *pll_reg;
static unsigned int last_target = ~0;
static unsigned int ftab_size;
static struct cpufreq_frequency_table *ftab;
static struct clk *_clk_mpll;
static struct clk *_clk_xtal;
static struct clk *clk_fclk;
static struct clk *clk_hclk;
static struct clk *clk_pclk;
static struct clk *clk_arm;
#ifdef CONFIG_ARM_S3C24XX_CPUFREQ_DEBUGFS
struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void)
{
return &cpu_cur;
}
struct s3c_iotimings *s3c_cpufreq_getiotimings(void)
{
return &s3c24xx_iotiming;
}
#endif /* CONFIG_ARM_S3C24XX_CPUFREQ_DEBUGFS */
static void s3c_cpufreq_getcur(struct s3c_cpufreq_config *cfg)
{
unsigned long fclk, pclk, hclk, armclk;
cfg->freq.fclk = fclk = clk_get_rate(clk_fclk);
cfg->freq.hclk = hclk = clk_get_rate(clk_hclk);
cfg->freq.pclk = pclk = clk_get_rate(clk_pclk);
cfg->freq.armclk = armclk = clk_get_rate(clk_arm);
cfg->pll.driver_data = __raw_readl(S3C2410_MPLLCON);
cfg->pll.frequency = fclk;
cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
cfg->divs.h_divisor = fclk / hclk;
cfg->divs.p_divisor = fclk / pclk;
}
static inline void s3c_cpufreq_calc(struct s3c_cpufreq_config *cfg)
{
unsigned long pll = cfg->pll.frequency;
cfg->freq.fclk = pll;
cfg->freq.hclk = pll / cfg->divs.h_divisor;
cfg->freq.pclk = pll / cfg->divs.p_divisor;
/* convert hclk into 10ths of nanoseconds for io calcs */
cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
}
static inline int closer(unsigned int target, unsigned int n, unsigned int c)
{
int diff_cur = abs(target - c);
int diff_new = abs(target - n);
return (diff_new < diff_cur);
}
static void s3c_cpufreq_show(const char *pfx,
struct s3c_cpufreq_config *cfg)
{
s3c_freq_dbg("%s: Fvco=%u, F=%lu, A=%lu, H=%lu (%u), P=%lu (%u)\n",
pfx, cfg->pll.frequency, cfg->freq.fclk, cfg->freq.armclk,
cfg->freq.hclk, cfg->divs.h_divisor,
cfg->freq.pclk, cfg->divs.p_divisor);
}
/* functions to wrapper the driver info calls to do the cpu specific work */
static void s3c_cpufreq_setio(struct s3c_cpufreq_config *cfg)
{
if (cfg->info->set_iotiming)
(cfg->info->set_iotiming)(cfg, &s3c24xx_iotiming);
}
static int s3c_cpufreq_calcio(struct s3c_cpufreq_config *cfg)
{
if (cfg->info->calc_iotiming)
return (cfg->info->calc_iotiming)(cfg, &s3c24xx_iotiming);
return 0;
}
static void s3c_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg)
{
(cfg->info->set_refresh)(cfg);
}
static void s3c_cpufreq_setdivs(struct s3c_cpufreq_config *cfg)
{
(cfg->info->set_divs)(cfg);
}
static int s3c_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg)
{
return (cfg->info->calc_divs)(cfg);
}
static void s3c_cpufreq_setfvco(struct s3c_cpufreq_config *cfg)
{
cfg->mpll = _clk_mpll;
(cfg->info->set_fvco)(cfg);
}
static inline void s3c_cpufreq_updateclk(struct clk *clk,
unsigned int freq)
{
clk_set_rate(clk, freq);
}
static int s3c_cpufreq_settarget(struct cpufreq_policy *policy,
unsigned int target_freq,
struct cpufreq_frequency_table *pll)
{
struct s3c_cpufreq_freqs freqs;
struct s3c_cpufreq_config cpu_new;
unsigned long flags;
cpu_new = cpu_cur; /* copy new from current */
s3c_cpufreq_show("cur", &cpu_cur);
/* TODO - check for DMA currently outstanding */
cpu_new.pll = pll ? *pll : cpu_cur.pll;
if (pll)
freqs.pll_changing = 1;
/* update our frequencies */
cpu_new.freq.armclk = target_freq;
cpu_new.freq.fclk = cpu_new.pll.frequency;
if (s3c_cpufreq_calcdivs(&cpu_new) < 0) {
pr_err("no divisors for %d\n", target_freq);
goto err_notpossible;
}
s3c_freq_dbg("%s: got divs\n", __func__);
s3c_cpufreq_calc(&cpu_new);
s3c_freq_dbg("%s: calculated frequencies for new\n", __func__);
if (cpu_new.freq.hclk != cpu_cur.freq.hclk) {
if (s3c_cpufreq_calcio(&cpu_new) < 0) {
pr_err("%s: no IO timings\n", __func__);
goto err_notpossible;
}
}
s3c_cpufreq_show("new", &cpu_new);
/* setup our cpufreq parameters */
freqs.old = cpu_cur.freq;
freqs.new = cpu_new.freq;
freqs.freqs.old = cpu_cur.freq.armclk / 1000;
freqs.freqs.new = cpu_new.freq.armclk / 1000;
/* update f/h/p clock settings before we issue the change
* notification, so that drivers do not need to do anything
* special if they want to recalculate on CPUFREQ_PRECHANGE. */
s3c_cpufreq_updateclk(_clk_mpll, cpu_new.pll.frequency);
s3c_cpufreq_updateclk(clk_fclk, cpu_new.freq.fclk);
s3c_cpufreq_updateclk(clk_hclk, cpu_new.freq.hclk);
s3c_cpufreq_updateclk(clk_pclk, cpu_new.freq.pclk);
/* start the frequency change */
cpufreq_freq_transition_begin(policy, &freqs.freqs);
/* If hclk is staying the same, then we do not need to
* re-write the IO or the refresh timings whilst we are changing
* speed. */
local_irq_save(flags);
/* is our memory clock slowing down? */
if (cpu_new.freq.hclk < cpu_cur.freq.hclk) {
s3c_cpufreq_setrefresh(&cpu_new);
s3c_cpufreq_setio(&cpu_new);
}
if (cpu_new.freq.fclk == cpu_cur.freq.fclk) {
/* not changing PLL, just set the divisors */
s3c_cpufreq_setdivs(&cpu_new);
} else {
if (cpu_new.freq.fclk < cpu_cur.freq.fclk) {
/* slow the cpu down, then set divisors */
s3c_cpufreq_setfvco(&cpu_new);
s3c_cpufreq_setdivs(&cpu_new);
} else {
/* set the divisors, then speed up */
s3c_cpufreq_setdivs(&cpu_new);
s3c_cpufreq_setfvco(&cpu_new);
}
}
/* did our memory clock speed up */
if (cpu_new.freq.hclk > cpu_cur.freq.hclk) {
s3c_cpufreq_setrefresh(&cpu_new);
s3c_cpufreq_setio(&cpu_new);
}
/* update our current settings */
cpu_cur = cpu_new;
local_irq_restore(flags);
/* notify everyone we've done this */
cpufreq_freq_transition_end(policy, &freqs.freqs, 0);
s3c_freq_dbg("%s: finished\n", __func__);
return 0;
err_notpossible:
pr_err("no compatible settings for %d\n", target_freq);
return -EINVAL;
}
/* s3c_cpufreq_target
*
* called by the cpufreq core to adjust the frequency that the CPU
* is currently running at.
*/
static int s3c_cpufreq_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cpufreq_frequency_table *pll;
unsigned int index;
/* avoid repeated calls which cause a needless amout of duplicated
* logging output (and CPU time as the calculation process is
* done) */
if (target_freq == last_target)
return 0;
last_target = target_freq;
s3c_freq_dbg("%s: policy %p, target %u, relation %u\n",
__func__, policy, target_freq, relation);
if (ftab) {
index = cpufreq_frequency_table_target(policy, target_freq,
relation);
s3c_freq_dbg("%s: adjust %d to entry %d (%u)\n", __func__,
target_freq, index, ftab[index].frequency);
target_freq = ftab[index].frequency;
}
target_freq *= 1000; /* convert target to Hz */
/* find the settings for our new frequency */
if (!pll_reg || cpu_cur.lock_pll) {
/* either we've not got any PLL values, or we've locked
* to the current one. */
pll = NULL;
} else {
struct cpufreq_policy tmp_policy;
/* we keep the cpu pll table in Hz, to ensure we get an
* accurate value for the PLL output. */
tmp_policy.min = policy->min * 1000;
tmp_policy.max = policy->max * 1000;
tmp_policy.cpu = policy->cpu;
tmp_policy.freq_table = pll_reg;
/* cpufreq_frequency_table_target returns the index
* of the table entry, not the value of
* the table entry's index field. */
index = cpufreq_frequency_table_target(&tmp_policy, target_freq,
relation);
pll = pll_reg + index;
s3c_freq_dbg("%s: target %u => %u\n",
__func__, target_freq, pll->frequency);
target_freq = pll->frequency;
}
return s3c_cpufreq_settarget(policy, target_freq, pll);
}
struct clk *s3c_cpufreq_clk_get(struct device *dev, const char *name)
{
struct clk *clk;
clk = clk_get(dev, name);
if (IS_ERR(clk))
pr_err("failed to get clock '%s'\n", name);
return clk;
}
static int s3c_cpufreq_init(struct cpufreq_policy *policy)
{
policy->clk = clk_arm;
return cpufreq_generic_init(policy, ftab, cpu_cur.info->latency);
}
static int __init s3c_cpufreq_initclks(void)
{
_clk_mpll = s3c_cpufreq_clk_get(NULL, "mpll");
_clk_xtal = s3c_cpufreq_clk_get(NULL, "xtal");
clk_fclk = s3c_cpufreq_clk_get(NULL, "fclk");
clk_hclk = s3c_cpufreq_clk_get(NULL, "hclk");
clk_pclk = s3c_cpufreq_clk_get(NULL, "pclk");
clk_arm = s3c_cpufreq_clk_get(NULL, "armclk");
if (IS_ERR(clk_fclk) || IS_ERR(clk_hclk) || IS_ERR(clk_pclk) ||
IS_ERR(_clk_mpll) || IS_ERR(clk_arm) || IS_ERR(_clk_xtal)) {
pr_err("%s: could not get clock(s)\n", __func__);
return -ENOENT;
}
pr_info("%s: clocks f=%lu,h=%lu,p=%lu,a=%lu\n",
__func__,
clk_get_rate(clk_fclk) / 1000,
clk_get_rate(clk_hclk) / 1000,
clk_get_rate(clk_pclk) / 1000,
clk_get_rate(clk_arm) / 1000);
return 0;
}
#ifdef CONFIG_PM
static struct cpufreq_frequency_table suspend_pll;
static unsigned int suspend_freq;
static int s3c_cpufreq_suspend(struct cpufreq_policy *policy)
{
suspend_pll.frequency = clk_get_rate(_clk_mpll);
suspend_pll.driver_data = __raw_readl(S3C2410_MPLLCON);
suspend_freq = clk_get_rate(clk_arm);
return 0;
}
static int s3c_cpufreq_resume(struct cpufreq_policy *policy)
{
int ret;
s3c_freq_dbg("%s: resuming with policy %p\n", __func__, policy);
last_target = ~0; /* invalidate last_target setting */
/* whilst we will be called later on, we try and re-set the
* cpu frequencies as soon as possible so that we do not end
* up resuming devices and then immediately having to re-set
* a number of settings once these devices have restarted.
*
* as a note, it is expected devices are not used until they
* have been un-suspended and at that time they should have
* used the updated clock settings.
*/
ret = s3c_cpufreq_settarget(NULL, suspend_freq, &suspend_pll);
if (ret) {
pr_err("%s: failed to reset pll/freq\n", __func__);
return ret;
}
return 0;
}
#else
#define s3c_cpufreq_resume NULL
#define s3c_cpufreq_suspend NULL
#endif
static struct cpufreq_driver s3c24xx_driver = {
.flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.target = s3c_cpufreq_target,
.get = cpufreq_generic_get,
.init = s3c_cpufreq_init,
.suspend = s3c_cpufreq_suspend,
.resume = s3c_cpufreq_resume,
.name = "s3c24xx",
};
int s3c_cpufreq_register(struct s3c_cpufreq_info *info)
{
if (!info || !info->name) {
pr_err("%s: failed to pass valid information\n", __func__);
return -EINVAL;
}
pr_info("S3C24XX CPU Frequency driver, %s cpu support\n",
info->name);
/* check our driver info has valid data */
BUG_ON(info->set_refresh == NULL);
BUG_ON(info->set_divs == NULL);
BUG_ON(info->calc_divs == NULL);
/* info->set_fvco is optional, depending on whether there
* is a need to set the clock code. */
cpu_cur.info = info;
/* Note, driver registering should probably update locktime */
return 0;
}
int __init s3c_cpufreq_setboard(struct s3c_cpufreq_board *board)
{
struct s3c_cpufreq_board *ours;
if (!board) {
pr_info("%s: no board data\n", __func__);
return -EINVAL;
}
/* Copy the board information so that each board can make this
* initdata. */
ours = kzalloc(sizeof(*ours), GFP_KERNEL);
if (ours == NULL) {
pr_err("%s: no memory\n", __func__);
return -ENOMEM;
}
*ours = *board;
cpu_cur.board = ours;
return 0;
}
static int __init s3c_cpufreq_auto_io(void)
{
int ret;
if (!cpu_cur.info->get_iotiming) {
pr_err("%s: get_iotiming undefined\n", __func__);
return -ENOENT;
}
pr_info("%s: working out IO settings\n", __func__);
ret = (cpu_cur.info->get_iotiming)(&cpu_cur, &s3c24xx_iotiming);
if (ret)
pr_err("%s: failed to get timings\n", __func__);
return ret;
}
/* if one or is zero, then return the other, otherwise return the min */
#define do_min(_a, _b) ((_a) == 0 ? (_b) : (_b) == 0 ? (_a) : min(_a, _b))
/**
* s3c_cpufreq_freq_min - find the minimum settings for the given freq.
* @dst: The destination structure
* @a: One argument.
* @b: The other argument.
*
* Create a minimum of each frequency entry in the 'struct s3c_freq',
* unless the entry is zero when it is ignored and the non-zero argument
* used.
*/
static void s3c_cpufreq_freq_min(struct s3c_freq *dst,
struct s3c_freq *a, struct s3c_freq *b)
{
dst->fclk = do_min(a->fclk, b->fclk);
dst->hclk = do_min(a->hclk, b->hclk);
dst->pclk = do_min(a->pclk, b->pclk);
dst->armclk = do_min(a->armclk, b->armclk);
}
static inline u32 calc_locktime(u32 freq, u32 time_us)
{
u32 result;
result = freq * time_us;
result = DIV_ROUND_UP(result, 1000 * 1000);
return result;
}
static void s3c_cpufreq_update_loctkime(void)
{
unsigned int bits = cpu_cur.info->locktime_bits;
u32 rate = (u32)clk_get_rate(_clk_xtal);
u32 val;
if (bits == 0) {
WARN_ON(1);
return;
}
val = calc_locktime(rate, cpu_cur.info->locktime_u) << bits;
val |= calc_locktime(rate, cpu_cur.info->locktime_m);
pr_info("%s: new locktime is 0x%08x\n", __func__, val);
__raw_writel(val, S3C2410_LOCKTIME);
}
static int s3c_cpufreq_build_freq(void)
{
int size, ret;
kfree(ftab);
size = cpu_cur.info->calc_freqtable(&cpu_cur, NULL, 0);
size++;
ftab = kzalloc(sizeof(*ftab) * size, GFP_KERNEL);
if (!ftab) {
pr_err("%s: no memory for tables\n", __func__);
return -ENOMEM;
}
ftab_size = size;
ret = cpu_cur.info->calc_freqtable(&cpu_cur, ftab, size);
s3c_cpufreq_addfreq(ftab, ret, size, CPUFREQ_TABLE_END);
return 0;
}
static int __init s3c_cpufreq_initcall(void)
{
int ret = 0;
if (cpu_cur.info && cpu_cur.board) {
ret = s3c_cpufreq_initclks();
if (ret)
goto out;
/* get current settings */
s3c_cpufreq_getcur(&cpu_cur);
s3c_cpufreq_show("cur", &cpu_cur);
if (cpu_cur.board->auto_io) {
ret = s3c_cpufreq_auto_io();
if (ret) {
pr_err("%s: failed to get io timing\n",
__func__);
goto out;
}
}
if (cpu_cur.board->need_io && !cpu_cur.info->set_iotiming) {
pr_err("%s: no IO support registered\n", __func__);
ret = -EINVAL;
goto out;
}
if (!cpu_cur.info->need_pll)
cpu_cur.lock_pll = 1;
s3c_cpufreq_update_loctkime();
s3c_cpufreq_freq_min(&cpu_cur.max, &cpu_cur.board->max,
&cpu_cur.info->max);
if (cpu_cur.info->calc_freqtable)
s3c_cpufreq_build_freq();
ret = cpufreq_register_driver(&s3c24xx_driver);
}
out:
return ret;
}
late_initcall(s3c_cpufreq_initcall);
/**
* s3c_plltab_register - register CPU PLL table.
* @plls: The list of PLL entries.
* @plls_no: The size of the PLL entries @plls.
*
* Register the given set of PLLs with the system.
*/
int s3c_plltab_register(struct cpufreq_frequency_table *plls,
unsigned int plls_no)
{
struct cpufreq_frequency_table *vals;
unsigned int size;
size = sizeof(*vals) * (plls_no + 1);
vals = kzalloc(size, GFP_KERNEL);
if (vals) {
memcpy(vals, plls, size);
pll_reg = vals;
/* write a terminating entry, we don't store it in the
* table that is stored in the kernel */
vals += plls_no;
vals->frequency = CPUFREQ_TABLE_END;
pr_info("%d PLL entries\n", plls_no);
} else
pr_err("no memory for PLL tables\n");
return vals ? 0 : -ENOMEM;
}