processor.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 2,497 行 · 第 1/5 页

		state.pointer = px;

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));

		status = acpi_extract_package(&(pss->package.elements[i]), 
			&format, &state);
		if (ACPI_FAILURE(status)) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
			result = -EFAULT;
			kfree(pr->performance->states);
			goto end;
		}

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
			"State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
			i, 
			(u32) px->core_frequency, 
			(u32) px->power, 
			(u32) px->transition_latency, 
			(u32) px->bus_master_latency,
			(u32) px->control, 
			(u32) px->status));

		if (!px->core_frequency) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data: freq is zero\n"));
			result = -EFAULT;
			kfree(pr->performance->states);
			goto end;
		}
	}

end:
	acpi_os_free(buffer.pointer);

	return_VALUE(result);
}


static int
acpi_processor_get_performance_info (
	struct acpi_processor	*pr)
{
	int			result = 0;
	acpi_status		status = AE_OK;
	acpi_handle		handle = NULL;

	ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info");

	if (!pr || !pr->performance || !pr->handle)
		return_VALUE(-EINVAL);

	acpi_processor_set_pdc(pr);

	status = acpi_get_handle(pr->handle, "_PCT", &handle);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
			"ACPI-based processor performance control unavailable\n"));
		return_VALUE(-ENODEV);
	}

	result = acpi_processor_get_performance_control(pr);
	if (result)
		return_VALUE(result);

	result = acpi_processor_get_performance_states(pr);
	if (result)
		return_VALUE(result);

	result = acpi_processor_get_platform_limit(pr);
	if (result)
		return_VALUE(result);

	return_VALUE(0);
}


#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
/* /proc/acpi/processor/../performance interface (DEPRECATED) */

static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
static struct file_operations acpi_processor_perf_fops = {
	.open 		= acpi_processor_perf_open_fs,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
{
	struct acpi_processor	*pr = (struct acpi_processor *)seq->private;
	int			i = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_perf_seq_show");

	if (!pr)
		goto end;

	if (!pr->performance) {
		seq_puts(seq, "<not supported>\n");
		goto end;
	}

	seq_printf(seq, "state count:             %d\n"
			"active state:            P%d\n",
			pr->performance->state_count,
			pr->performance->state);

	seq_puts(seq, "states:\n");
	for (i = 0; i < pr->performance->state_count; i++)
		seq_printf(seq, "   %cP%d:                  %d MHz, %d mW, %d uS\n",
			(i == pr->performance->state?'*':' '), i,
			(u32) pr->performance->states[i].core_frequency,
			(u32) pr->performance->states[i].power,
			(u32) pr->performance->states[i].transition_latency);

end:
	return 0;
}

static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_processor_perf_seq_show,
						PDE(inode)->data);
}

static ssize_t
acpi_processor_write_performance (
        struct file		*file,
        const char		__user *buffer,
        size_t			count,
        loff_t			*data)
{
	int			result = 0;
	struct seq_file		*m = (struct seq_file *) file->private_data;
	struct acpi_processor	*pr = (struct acpi_processor *) m->private;
	struct acpi_processor_performance *perf;
	char			state_string[12] = {'\0'};
	unsigned int            new_state = 0;
	struct cpufreq_policy   policy;

	ACPI_FUNCTION_TRACE("acpi_processor_write_performance");

	if (!pr || (count > sizeof(state_string) - 1))
		return_VALUE(-EINVAL);

	perf = pr->performance;
	if (!perf)
		return_VALUE(-EINVAL);
	
	if (copy_from_user(state_string, buffer, count))
		return_VALUE(-EFAULT);
	
	state_string[count] = '\0';
	new_state = simple_strtoul(state_string, NULL, 0);

	if (new_state >= perf->state_count)
		return_VALUE(-EINVAL);

	cpufreq_get_policy(&policy, pr->id);

	policy.cpu = pr->id;
	policy.min = perf->states[new_state].core_frequency * 1000;
	policy.max = perf->states[new_state].core_frequency * 1000;

	result = cpufreq_set_policy(&policy);
	if (result)
		return_VALUE(result);

	return_VALUE(count);
}

static void
acpi_cpufreq_add_file (
	struct acpi_processor *pr)
{
	struct proc_dir_entry	*entry = NULL;
	struct acpi_device	*device = NULL;

	ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");

	if (acpi_bus_get_device(pr->handle, &device))
		return_VOID;

	/* add file 'performance' [R/W] */
	entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
		  S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
	if (!entry)
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
			"Unable to create '%s' fs entry\n",
			ACPI_PROCESSOR_FILE_PERFORMANCE));
	else {
		entry->proc_fops = &acpi_processor_perf_fops;
		entry->proc_fops->write = acpi_processor_write_performance;
		entry->data = acpi_driver_data(device);
		entry->owner = THIS_MODULE;
	}
	return_VOID;
}

static void
acpi_cpufreq_remove_file (
	struct acpi_processor *pr)
{
	struct acpi_device	*device = NULL;

	ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");

	if (acpi_bus_get_device(pr->handle, &device))
		return_VOID;

	/* remove file 'performance' */
	remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
		  acpi_device_dir(device));

	return_VOID;
}

#else
static void acpi_cpufreq_add_file (struct acpi_processor *pr) { return; }
static void acpi_cpufreq_remove_file (struct acpi_processor *pr) { return; }
#endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */


int 
acpi_processor_register_performance (
	struct acpi_processor_performance * performance,
	unsigned int cpu)
{
	struct acpi_processor *pr;

	ACPI_FUNCTION_TRACE("acpi_processor_register_performance");

	if (!acpi_processor_ppc_is_init)
		return_VALUE(-EINVAL);

	down(&performance_sem);

	pr = processors[cpu];
	if (!pr) {
		up(&performance_sem);
		return_VALUE(-ENODEV);
	}

	if (pr->performance) {
		up(&performance_sem);
		return_VALUE(-EBUSY);
	}

	pr->performance = performance;

	if (acpi_processor_get_performance_info(pr)) {
		pr->performance = NULL;
		up(&performance_sem);
		return_VALUE(-EIO);
	}

	acpi_cpufreq_add_file(pr);

	up(&performance_sem);
	return_VALUE(0);
}
EXPORT_SYMBOL(acpi_processor_register_performance);


void 
acpi_processor_unregister_performance (
	struct acpi_processor_performance * performance,
	unsigned int cpu)
{
	struct acpi_processor *pr;

	ACPI_FUNCTION_TRACE("acpi_processor_unregister_performance");

	if (!acpi_processor_ppc_is_init)
		return_VOID;

	down(&performance_sem);

	pr = processors[cpu];
	if (!pr) {
		up(&performance_sem);
		return_VOID;
	}

	kfree(pr->performance->states);
	pr->performance = NULL;

	acpi_cpufreq_remove_file(pr);

	up(&performance_sem);

	return_VOID;
}
EXPORT_SYMBOL(acpi_processor_unregister_performance);


/* for the rest of it, check arch/i386/kernel/cpu/cpufreq/acpi.c */

#else  /* !CONFIG_CPU_FREQ */

static void acpi_processor_ppc_init(void) { return; }
static void acpi_processor_ppc_exit(void) { return; }

static int acpi_processor_ppc_has_changed(struct acpi_processor *pr) {
	static unsigned int printout = 1;
	if (printout) {
		printk(KERN_WARNING "Warning: Processor Platform Limit event detected, but not handled.\n");
		printk(KERN_WARNING "Consider compiling CPUfreq support into your kernel.\n");
		printout = 0;
	}
	return 0;
}

#endif /* CONFIG_CPU_FREQ */

/* --------------------------------------------------------------------------
                              Throttling Control
   -------------------------------------------------------------------------- */

static int
acpi_processor_get_throttling (
	struct acpi_processor	*pr)
{
	int			state = 0;
	u32			value = 0;
	u32			duty_mask = 0;
	u32			duty_value = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_get_throttling");

	if (!pr)
		return_VALUE(-EINVAL);

	if (!pr->flags.throttling)
		return_VALUE(-ENODEV);

	pr->throttling.state = 0;

	local_irq_disable();

	duty_mask = pr->throttling.state_count - 1;

	duty_mask <<= pr->throttling.duty_offset;

	value = inl(pr->throttling.address);

	/*
	 * Compute the current throttling state when throttling is enabled
	 * (bit 4 is on).
	 */
	if (value & 0x10) {
		duty_value = value & duty_mask;
		duty_value >>= pr->throttling.duty_offset;

		if (duty_value)
			state = pr->throttling.state_count-duty_value;
	}

	pr->throttling.state = state;

	local_irq_enable();

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
		"Throttling state is T%d (%d%% throttling applied)\n",
		state, pr->throttling.states[state].performance));

	return_VALUE(0);
}


static int
acpi_processor_set_throttling (
	struct acpi_processor	*pr,
	int			state)
{
	u32                     value = 0;
	u32                     duty_mask = 0;
	u32                     duty_value = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_set_throttling");

	if (!pr)
		return_VALUE(-EINVAL);

	if ((state < 0) || (state > (pr->throttling.state_count - 1)))
		return_VALUE(-EINVAL);

	if (!pr->flags.throttling)
		return_VALUE(-ENODEV);

	if (state == pr->throttling.state)
		return_VALUE(0);

	local_irq_disable();

	/*
	 * Calculate the duty_value and duty_mask.
	 */
	if (state) {
		duty_value = pr->throttling.state_count - state;

		duty_value <<= pr->throttling.duty_offset;

		/* Used to clear all duty_value bits */
		duty_mask = pr->throttling.state_count - 1;

		duty_mask <<= acpi_fadt.duty_offset;
		duty_mask = ~duty_mask;
	}

	/*
	 * Disable throttling by writing a 0 to bit 4.  Note that we must
	 * turn it off before you can change the duty_value.
	 */
	value = inl(pr->throttling.address);
	if (value & 0x10) {
		value &= 0xFFFFFFEF;
		outl(value, pr->throttling.address);
	}

	/*
	 * Write the new duty_value and then enable throttling.  Note
	 * that a state value of 0 leaves throttling disabled.
	 */
	if (state) {
		value &= duty_mask;
		value |= duty_value;
		outl(value, pr->throttling.address);

		value |= 0x00000010;
		outl(value, pr->throttling.address);
	}

	pr->throttling.state = state;

	local_irq_enable();

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
		"Throttling state set to T%d (%d%%)\n", state, 
		(pr->throttling.states[state].performance?pr->throttling.states[state].performance/10:0)));

	return_VALUE(0);
}


static int
acpi_processor_get_throttling_info (
	struct acpi_processor	*pr)
{
	int			result = 0;
	int			step = 0;
	int			i = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_get_throttling_info");

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
		"pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
		pr->throttling.address,
		pr->throttling.duty_offset,
		pr->throttling.duty_width));

	if (!pr)
		return_VALUE(-EINVAL);

	/* TBD: Support ACPI 2.0 objects */

	if (!pr->throttling.address) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
		return_VALUE(0);
	}
	else if (!pr->throttling.duty_width) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
		return_VALUE(0);
	}
	/* TBD: Support duty_cycle values that span bit 4. */
	else if ((pr->throttling.duty_offset
		+ pr->throttling.duty_width) > 4) {
		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "duty_cycle spans bit 4\n"));
		return_VALUE(0);
	}

	/*
	 * PIIX4 Errata: We don't support throttling on the original PIIX4.
	 * This shouldn't be an issue as few (if any) mobile systems ever
	 * used this part.
	 */
	if (errata.piix4.throttle) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
			"Throttling not supported on PIIX4 A- or B-step\n"));
		return_VALUE(0);
	}

	pr->throttling.state_count = 1 << acpi_fadt.duty_width;

	/*
	 * Compute state values. Note that throttling displays a linear power/
	 * performance relationship (at 50% performance the CPU will consume
	 * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
	 */