/*
==============================================================
Initialisation function sets up the CPU policy for first use
==============================================================
*/
static int bcm2835_cpufreq_driver_init(struct cpufreq_policy *policy)
{
/* measured value of how long it takes to change frequency */
policy->cpuinfo.transition_latency = 355000; /* ns */
/* now find out what the maximum and minimum frequencies are */
policy->min = policy->cpuinfo.min_freq = bcm2835_cpufreq_get_clock(VCMSG_GET_MIN_CLOCK);
policy->max = policy->cpuinfo.max_freq = bcm2835_cpufreq_get_clock(VCMSG_GET_MAX_CLOCK);
policy->cur = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
print_info("min=%d max=%d cur=%d\n", policy->min, policy->max, policy->cur);
return 0;
}
static int bcm2835_cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation)
{
unsigned int target = target_freq;
unsigned int cur = policy->cur;
print_debug("%s: min=%d max=%d cur=%d target=%d\n",policy->governor->name,policy->min,policy->max,policy->cur,target_freq);
/* if we are above min and using ondemand, then just use max */
if (strcmp("ondemand", policy->governor->name)==0 && target > policy->min)
target = policy->max;
/* if the frequency is the same, just quit */
if (target == policy->cur)
return 0;
/* otherwise were good to set the clock frequency */
policy->cur = bcm2835_cpufreq_set_clock(policy->cur, target);
if (!policy->cur)
{
print_err("Error occurred setting a new frequency (%d)!\n", target);
policy->cur = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
return -EINVAL;
}
print_debug("Freq %d->%d (min=%d max=%d target=%d request=%d)\n", cur, policy->cur, policy->min, policy->max, target_freq, target);
return 0;
}
/*
==============================================================
Initialisation function sets up the CPU policy for first use
==============================================================
*/
static int bcm2835_cpufreq_driver_init(struct cpufreq_policy *policy)
{
/* measured value of how long it takes to change frequency */
const unsigned int transition_latency = 355000; /* ns */
if (!rpi_firmware_get(NULL)) {
print_err("Firmware is not available\n");
return -ENODEV;
}
/* now find out what the maximum and minimum frequencies are */
bcm2835_freq_table[0].frequency = bcm2835_cpufreq_get_clock(RPI_FIRMWARE_GET_MIN_CLOCK_RATE);
bcm2835_freq_table[1].frequency = bcm2835_cpufreq_get_clock(RPI_FIRMWARE_GET_MAX_CLOCK_RATE);
print_info("min=%d max=%d\n", bcm2835_freq_table[0].frequency, bcm2835_freq_table[1].frequency);
return cpufreq_generic_init(policy, bcm2835_freq_table, transition_latency);
}
static unsigned int bcm2835_cpufreq_driver_get(unsigned int cpu)
{
unsigned int actual_rate = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
print_debug("cpu=%d\n", actual_rate);
return actual_rate;
}
static unsigned int bcm2835_cpufreq_driver_get(unsigned int cpu)
{
unsigned int actual_rate = bcm2835_cpufreq_get_clock(RPI_FIRMWARE_GET_CLOCK_RATE);
print_debug("cpu%d: freq=%d\n", cpu, actual_rate);
return actual_rate <= bcm2835_freq_table[0].frequency ? bcm2835_freq_table[0].frequency : bcm2835_freq_table[1].frequency;
}