linux/drivers/cpufreq/cris-artpec3-cpufreq.c

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#include <linux/init.h>
#include <linux/module.h>
#include <linux/cpufreq.h>
#include <hwregs/reg_map.h>
#include <hwregs/reg_rdwr.h>
#include <hwregs/clkgen_defs.h>
#include <hwregs/ddr2_defs.h>
static int
cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
void *data);
static struct notifier_block cris_sdram_freq_notifier_block = {
.notifier_call = cris_sdram_freq_notifier
};
static struct cpufreq_frequency_table cris_freq_table[] = {
{0, 0x01, 6000},
{0, 0x02, 200000},
{0, 0, CPUFREQ_TABLE_END},
};
static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
{
reg_clkgen_rw_clk_ctrl clk_ctrl;
clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
return clk_ctrl.pll ? 200000 : 6000;
}
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 14:15:48 +00:00
static int cris_freq_target(struct cpufreq_policy *policy, unsigned int state)
{
reg_clkgen_rw_clk_ctrl clk_ctrl;
clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
local_irq_disable();
/* Even though we may be SMP they will share the same clock
* so all settings are made on CPU0. */
if (cris_freq_table[state].frequency == 200000)
clk_ctrl.pll = 1;
else
clk_ctrl.pll = 0;
REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);
local_irq_enable();
return 0;
}
static int cris_freq_cpu_init(struct cpufreq_policy *policy)
{
return cpufreq_generic_init(policy, cris_freq_table, 1000000);
}
static struct cpufreq_driver cris_freq_driver = {
.get = cris_freq_get_cpu_frequency,
.verify = cpufreq_generic_frequency_table_verify,
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 14:15:48 +00:00
.target_index = cris_freq_target,
.init = cris_freq_cpu_init,
.name = "cris_freq",
.attr = cpufreq_generic_attr,
};
static int __init cris_freq_init(void)
{
int ret;
ret = cpufreq_register_driver(&cris_freq_driver);
cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
CPUFREQ_TRANSITION_NOTIFIER);
return ret;
}
static int
cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
void *data)
{
int i;
struct cpufreq_freqs *freqs = data;
if (val == CPUFREQ_PRECHANGE) {
reg_ddr2_rw_cfg cfg =
REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);
if (freqs->new == 200000)
for (i = 0; i < 50000; i++);
REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
}
return 0;
}
module_init(cris_freq_init);