Beispiel #1
0
static void drv_write(struct drv_cmd *cmd)
{
    if (cpumask_equal(cmd->mask, cpumask_of(smp_processor_id())))
        do_drv_write((void *)cmd);
    else
        on_selected_cpus(cmd->mask, do_drv_write, cmd, 1);
}
Beispiel #2
0
static void drv_write(struct drv_cmd *cmd)
{
	int this_cpu;

	this_cpu = get_cpu();
	if (cpumask_test_cpu(this_cpu, cmd->mask))
		do_drv_write(cmd);
	smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
	put_cpu();
}
Beispiel #3
0
static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
{
	struct acpi_processor_performance *perf = to_perf_data(data);
	struct drv_cmd cmd = {
		.reg = &perf->control_register,
		.func.read = data->cpu_freq_read,
	};
	int err;

	err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
	return cmd.val;
}

/* Called via smp_call_function_many(), on the target CPUs */
static void do_drv_write(void *_cmd)
{
	struct drv_cmd *cmd = _cmd;

	cmd->func.write(cmd->reg, cmd->val);
}

static void drv_write(struct acpi_cpufreq_data *data,
		      const struct cpumask *mask, u32 val)
{
	struct acpi_processor_performance *perf = to_perf_data(data);
	struct drv_cmd cmd = {
		.reg = &perf->control_register,
		.val = val,
		.func.write = data->cpu_freq_write,
	};
	int this_cpu;

	this_cpu = get_cpu();
	if (cpumask_test_cpu(this_cpu, mask))
		do_drv_write(&cmd);

	smp_call_function_many(mask, do_drv_write, &cmd, 1);
	put_cpu();
}

static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
{
	u32 val;

	if (unlikely(cpumask_empty(mask)))
		return 0;

	val = drv_read(data, mask);

	pr_debug("get_cur_val = %u\n", val);

	return val;
}

static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
{
	struct acpi_cpufreq_data *data;
	struct cpufreq_policy *policy;
	unsigned int freq;
	unsigned int cached_freq;

	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);

	policy = cpufreq_cpu_get_raw(cpu);
	if (unlikely(!policy))
		return 0;

	data = policy->driver_data;
	if (unlikely(!data || !policy->freq_table))
		return 0;

	cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
	freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
	if (freq != cached_freq) {
		/*
		 * The dreaded BIOS frequency change behind our back.
		 * Force set the frequency on next target call.
		 */
		data->resume = 1;
	}

	pr_debug("cur freq = %u\n", freq);

	return freq;
}

static unsigned int check_freqs(struct cpufreq_policy *policy,
				const struct cpumask *mask, unsigned int freq)
{
	struct acpi_cpufreq_data *data = policy->driver_data;
	unsigned int cur_freq;
	unsigned int i;

	for (i = 0; i < 100; i++) {
		cur_freq = extract_freq(policy, get_cur_val(mask, data));
		if (cur_freq == freq)
			return 1;
		udelay(10);
	}
	return 0;
}

static int acpi_cpufreq_target(struct cpufreq_policy *policy,
			       unsigned int index)
{
	struct acpi_cpufreq_data *data = policy->driver_data;
	struct acpi_processor_performance *perf;
	const struct cpumask *mask;
	unsigned int next_perf_state = 0; /* Index into perf table */
	int result = 0;

	if (unlikely(!data)) {
		return -ENODEV;
	}

	perf = to_perf_data(data);
	next_perf_state = policy->freq_table[index].driver_data;
	if (perf->state == next_perf_state) {
		if (unlikely(data->resume)) {
			pr_debug("Called after resume, resetting to P%d\n",
				next_perf_state);
			data->resume = 0;
		} else {
			pr_debug("Already at target state (P%d)\n",
				next_perf_state);
			return 0;
		}
	}

	/*
	 * The core won't allow CPUs to go away until the governor has been
	 * stopped, so we can rely on the stability of policy->cpus.
	 */
	mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
		cpumask_of(policy->cpu) : policy->cpus;

	drv_write(data, mask, perf->states[next_perf_state].control);

	if (acpi_pstate_strict) {
		if (!check_freqs(policy, mask,
				 policy->freq_table[index].frequency)) {
			pr_debug("acpi_cpufreq_target failed (%d)\n",
				policy->cpu);
			result = -EAGAIN;
		}
	}

	if (!result)
		perf->state = next_perf_state;

	return result;
}

unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
				      unsigned int target_freq)
{
	struct acpi_cpufreq_data *data = policy->driver_data;
	struct acpi_processor_performance *perf;
	struct cpufreq_frequency_table *entry;
	unsigned int next_perf_state, next_freq, index;

	/*
	 * Find the closest frequency above target_freq.
	 */
	if (policy->cached_target_freq == target_freq)
		index = policy->cached_resolved_idx;
	else
		index = cpufreq_table_find_index_dl(policy, target_freq);

	entry = &policy->freq_table[index];
	next_freq = entry->frequency;
	next_perf_state = entry->driver_data;

	perf = to_perf_data(data);
	if (perf->state == next_perf_state) {
		if (unlikely(data->resume))
			data->resume = 0;
		else
			return next_freq;
	}

	data->cpu_freq_write(&perf->control_register,
			     perf->states[next_perf_state].control);
	perf->state = next_perf_state;
	return next_freq;
}

static unsigned long
acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
{
	struct acpi_processor_performance *perf;

	perf = to_perf_data(data);
	if (cpu_khz) {
		/* search the closest match to cpu_khz */
		unsigned int i;
		unsigned long freq;
		unsigned long freqn = perf->states[0].core_frequency * 1000;

		for (i = 0; i < (perf->state_count-1); i++) {
			freq = freqn;
			freqn = perf->states[i+1].core_frequency * 1000;
			if ((2 * cpu_khz) > (freqn + freq)) {
				perf->state = i;
				return freq;
			}
		}
		perf->state = perf->state_count-1;
		return freqn;
	} else {
		/* assume CPU is at P0... */
		perf->state = 0;
		return perf->states[0].core_frequency * 1000;
	}
}

static void free_acpi_perf_data(void)
{
	unsigned int i;

	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
	for_each_possible_cpu(i)
		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
				 ->shared_cpu_map);
	free_percpu(acpi_perf_data);
}