/*
 * OMAP powerdomain control
 *
 * Copyright (C) 2007-2008, 2011 Texas Instruments, Inc.
 * Copyright (C) 2007-2011 Nokia Corporation
 *
 * Written by Paul Walmsley
 * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com>
 * State counting code by Tero Kristo <tero.kristo@nokia.com>
 *
 * 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.
 */
#undef DEBUG

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <trace/events/power.h>

#include "cm2xxx_3xxx.h"
#include "prcm44xx.h"
#include "cm44xx.h"
#include "prm2xxx_3xxx.h"
#include "prm44xx.h"

#include <asm/cpu.h>

#include "powerdomain.h"
#include "clockdomain.h"

#include "soc.h"
#include "pm.h"

#define PWRDM_TRACE_STATES_FLAG	(1<<31)

enum {
	PWRDM_STATE_NOW = 0,
	PWRDM_STATE_PREV,
};


/* pwrdm_list contains all registered struct powerdomains */
static LIST_HEAD(pwrdm_list);

static struct pwrdm_ops *arch_pwrdm;

/* Private functions */

static struct powerdomain *_pwrdm_lookup(const char *name)
{
	struct powerdomain *pwrdm, *temp_pwrdm;

	pwrdm = NULL;

	list_for_each_entry(temp_pwrdm, &pwrdm_list, node) {
		if (!strcmp(name, temp_pwrdm->name)) {
			pwrdm = temp_pwrdm;
			break;
		}
	}

	return pwrdm;
}

/**
 * _pwrdm_register - register a powerdomain
 * @pwrdm: struct powerdomain * to register
 *
 * Adds a powerdomain to the internal powerdomain list.  Returns
 * -EINVAL if given a null pointer, -EEXIST if a powerdomain is
 * already registered by the provided name, or 0 upon success.
 */
static int _pwrdm_register(struct powerdomain *pwrdm)
{
	int i;
	struct voltagedomain *voltdm;

	if (!pwrdm || !pwrdm->name)
		return -EINVAL;

	if (cpu_is_omap44xx() &&
	    pwrdm->prcm_partition == OMAP4430_INVALID_PRCM_PARTITION) {
		pr_err("powerdomain: %s: missing OMAP4 PRCM partition ID\n",
		       pwrdm->name);
		return -EINVAL;
	}

	if (_pwrdm_lookup(pwrdm->name))
		return -EEXIST;

	voltdm = voltdm_lookup(pwrdm->voltdm.name);
	if (!voltdm) {
		pr_err("powerdomain: %s: voltagedomain %s does not exist\n",
		       pwrdm->name, pwrdm->voltdm.name);
		return -EINVAL;
	}
	pwrdm->voltdm.ptr = voltdm;
	INIT_LIST_HEAD(&pwrdm->voltdm_node);
	voltdm_add_pwrdm(voltdm, pwrdm);

	list_add(&pwrdm->node, &pwrdm_list);

	/* Initialize the powerdomain's state counter */
	for (i = 0; i < PWRDM_MAX_PWRSTS; i++)
		pwrdm->state_counter[i] = 0;

	pwrdm->ret_logic_off_counter = 0;
	for (i = 0; i < pwrdm->banks; i++)
		pwrdm->ret_mem_off_counter[i] = 0;

	pwrdm_wait_transition(pwrdm);
	pwrdm->state = pwrdm_read_pwrst(pwrdm);
	pwrdm->state_counter[pwrdm->state] = 1;

	pr_debug("powerdomain: registered %s\n", pwrdm->name);

	return 0;
}

static void _update_logic_membank_counters(struct powerdomain *pwrdm)
{
	int i;
	u8 prev_logic_pwrst, prev_mem_pwrst;

	prev_logic_pwrst = pwrdm_read_prev_logic_pwrst(pwrdm);
	if ((pwrdm->pwrsts_logic_ret == PWRSTS_OFF_RET) &&
	    (prev_logic_pwrst == PWRDM_POWER_OFF))
		pwrdm->ret_logic_off_counter++;

	for (i = 0; i < pwrdm->banks; i++) {
		prev_mem_pwrst = pwrdm_read_prev_mem_pwrst(pwrdm, i);

		if ((pwrdm->pwrsts_mem_ret[i] == PWRSTS_OFF_RET) &&
		    (prev_mem_pwrst == PWRDM_POWER_OFF))
			pwrdm->ret_mem_off_counter[i]++;
	}
}

static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag)
{

	int prev, state, trace_state = 0;

	if (pwrdm == NULL)
		return -EINVAL;

	state = pwrdm_read_pwrst(pwrdm);

	switch (flag) {
	case PWRDM_STATE_NOW:
		prev = pwrdm->state;
		break;
	case PWRDM_STATE_PREV:
		prev = pwrdm_read_prev_pwrst(pwrdm);
		if (pwrdm->state != prev)
			pwrdm->state_counter[prev]++;
		if (prev == PWRDM_POWER_RET)
			_update_logic_membank_counters(pwrdm);
		/*
		 * If the power domain did not hit the desired state,
		 * generate a trace event with both the desired and hit states
		 */
		if (state != prev) {
			trace_state = (PWRDM_TRACE_STATES_FLAG |
				       ((state & OMAP_POWERSTATE_MASK) << 8) |
				       ((prev & OMAP_POWERSTATE_MASK) << 0));
			trace_power_domain_target(pwrdm->name, trace_state,
						  smp_processor_id());
		}
		break;
	default:
		return -EINVAL;
	}

	if (state != prev)
		pwrdm->state_counter[state]++;

	pm_dbg_update_time(pwrdm, prev);

	pwrdm->state = state;

	return 0;
}

static int _pwrdm_pre_transition_cb(struct powerdomain *pwrdm, void *unused)
{
	pwrdm_clear_all_prev_pwrst(pwrdm);
	_pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW);
	return 0;
}

static int _pwrdm_post_transition_cb(struct powerdomain *pwrdm, void *unused)
{
	_pwrdm_state_switch(pwrdm, PWRDM_STATE_PREV);
	return 0;
}

/* Public functions */

/**
 * pwrdm_register_platform_funcs - register powerdomain implementation fns
 * @po: func pointers for arch specific implementations
 *
 * Register the list of function pointers used to implement the
 * powerdomain functions on different OMAP SoCs.  Should be called
 * before any other pwrdm_register*() function.  Returns -EINVAL if
 * @po is null, -EEXIST if platform functions have already been
 * registered, or 0 upon success.
 */
int pwrdm_register_platform_funcs(struct pwrdm_ops *po)
{
	if (!po)
		return -EINVAL;

	if (arch_pwrdm)
		return -EEXIST;

	arch_pwrdm = po;

	return 0;
}

/**
 * pwrdm_register_pwrdms - register SoC powerdomains
 * @ps: pointer to an array of struct powerdomain to register
 *
 * Register the powerdomains available on a particular OMAP SoC.  Must
 * be called after pwrdm_register_platform_funcs().  May be called
 * multiple times.  Returns -EACCES if called before
 * pwrdm_register_platform_funcs(); -EINVAL if the argument @ps is
 * null; or 0 upon success.
 */
int pwrdm_register_pwrdms(struct powerdomain **ps)
{
	struct powerdomain **p = NULL;

	if (!arch_pwrdm)
		return -EEXIST;

	if (!ps)
		return -EINVAL;

	for (p = ps; *p; p++)
		_pwrdm_register(*p);

	return 0;
}

/**
 * pwrdm_complete_init - set up the powerdomain layer
 *
 * Do whatever is necessary to initialize registered powerdomains and
 * powerdomain code.  Currently, this programs the next power state