/*
 * OMAP4 powerdomain control
 *
 * Copyright (C) 2009-2010, 2012 Texas Instruments, Inc.
 * Copyright (C) 2007-2009 Nokia Corporation
 *
 * Derived from mach-omap2/powerdomain.c written by Paul Walmsley
 * Rajendra Nayak <rnayak@ti.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.
 */

#include <linux/io.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/bug.h>

#include "powerdomain.h"
#include <plat/prcm.h>
#include "prm2xxx_3xxx.h"
#include "prm44xx.h"
#include "prminst44xx.h"
#include "prm-regbits-44xx.h"

static int omap4_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
{
	omap4_prminst_rmw_inst_reg_bits(OMAP_POWERSTATE_MASK,
					(pwrst << OMAP_POWERSTATE_SHIFT),
					pwrdm->prcm_partition,
					pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
	return 0;
}

static int omap4_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);
	v &= OMAP_POWERSTATE_MASK;
	v >>= OMAP_POWERSTATE_SHIFT;

	return v;
}

static int omap4_pwrdm_read_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTST);
	v &= OMAP_POWERSTATEST_MASK;
	v >>= OMAP_POWERSTATEST_SHIFT;

	return v;
}

static int omap4_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTST);
	v &= OMAP4430_LASTPOWERSTATEENTERED_MASK;
	v >>= OMAP4430_LASTPOWERSTATEENTERED_SHIFT;

	return v;
}

static int omap4_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
{
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOWPOWERSTATECHANGE_MASK,
					(1 << OMAP4430_LOWPOWERSTATECHANGE_SHIFT),
					pwrdm->prcm_partition,
					pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
	return 0;
}

static int omap4_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
{
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LASTPOWERSTATEENTERED_MASK,
					OMAP4430_LASTPOWERSTATEENTERED_MASK,
					pwrdm->prcm_partition,
					pwrdm->prcm_offs, OMAP4_PM_PWSTST);
	return 0;
}

static int omap4_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
{
	u32 v;

	v = pwrst << __ffs(OMAP4430_LOGICRETSTATE_MASK);
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOGICRETSTATE_MASK, v,
					pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);

	return 0;
}

static int omap4_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
				    u8 pwrst)
{
	u32 m;

	m = omap2_pwrdm_get_mem_bank_onstate_mask(bank);

	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
					pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);

	return 0;
}

static int omap4_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
				     u8 pwrst)
{
	u32 m;

	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
					pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);

	return 0;
}

static int omap4_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTST);
	v &= OMAP4430_LOGICSTATEST_MASK;
	v >>= OMAP4430_LOGICSTATEST_SHIFT;

	return v;
}

static int omap4_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);
	v &= OMAP4430_LOGICRETSTATE_MASK;
	v >>= OMAP4430_LOGICRETSTATE_SHIFT;

	return v;
}

/**
 * omap4_pwrdm_read_prev_logic_pwrst - read the previous logic powerstate
 * @pwrdm: struct powerdomain * to read the state for
 *
 * Reads the previous logic powerstate for a powerdomain. This
 * function must determine the previous logic powerstate by first
 * checking the previous powerstate for the domain. If that was OFF,
 * then logic has been lost. If previous state was RETENTION, the
 * function reads the setting for the next retention logic state to
 * see the actual value.  In every other case, the logic is
 * retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
 * depending whether the logic was retained or not.
 */
static int omap4_pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
{
	int state;

	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

	if (state == PWRDM_POWER_OFF)
		return PWRDM_POWER_OFF;

	if (state != PWRDM_POWER_RET)
		return PWRDM_POWER_RET;

	return omap4_pwrdm_read_logic_retst(pwrdm);
}

static int omap4_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
{
	u32 m, v;

	m = omap2_pwrdm_get_mem_bank_stst_mask(bank);

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTST);
	v &= m;
	v >>= __ffs(m);

	return v;
}

static int omap4_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
{
	u32 m, v;

	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
					OMAP4_PM_PWSTCTRL);
	v &= m;
	v >>= __ffs(m);

	return v;
}

/**
 * omap4_pwrdm_read_prev_mem_pwrst - reads the previous memory powerstate
 * @pwrdm: struct powerdomain * to read mem powerstate for
 * @bank: memory bank index
 *
 * Reads the previous memory powerstate for a powerdomain. This
 * function must determine the previous memory powerstate by first
 * checking the previous powerstate for the domain. If that was OFF,
 * then logic has been lost. If previous state was RETENTION, the
 * function reads the setting for the next memory retention state to
 * see the actual value.  In every other case, the logic is
 * retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
 * depending whether logic was retained or not.
 */
static int omap4_pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
{
	int state;

	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

	if (state == PWRDM_POWER_OFF)
		return PWRDM_POWER_OFF;

	if (state != PWRDM_POWER_RET)
		return PWRDM_POWER_RET;

	return omap4_pwrdm_read_mem_retst(pwrdm, bank);
}

static int omap4_pwrdm_wait_transition(struct powerdomain *pwrdm)
{
	u32 c = 0;

	/*
	 * REVISIT: pwrdm_wait_transition() may be better implemented
	 * via a callback and a periodic timer check -- how long do we expect
	 * powerdomain transitions to take?
	 */

	/* XXX Is this udelay() value meaningful? */
	while ((omap4_prminst_read_inst_reg(pwrdm->prcm_partition,
					    pwrdm->prcm_offs,
					    OMAP4_PM_PWSTST) &
		OMAP_INTRANSITION_MASK) &&
	       (c++ < PWRDM_TRANSITION_BAILOUT))
		udelay(1);

	if (c > PWRDM_TRANSITION_BAILOUT) {
		pr_err("powerdomain: %s: waited too long to complete transition\n",
		       pwrdm->name);
		return -EAGAIN;
	}

	pr_debug("powerdomain: completed transition in %d loops\n", c);

	return 0;
}

struct pwrdm_ops omap4_pwrdm_operations = {
	.pwrdm_set_next_pwrst	= omap4_pwrdm_set_next_pwrst,
	.pwrdm_read_next_pwrst	= omap4_pwrdm_read_next_pwrst,
	.pwrdm_read_pwrst	= omap4_pwrdm_read_pwrst,
	.pwrdm_read_prev_pwrst	= omap4_pwrdm_read_prev_pwrst,
	.pwrdm_set_lowpwrstchange	= omap4_pwrdm_set_lowpwrstchange,
	.pwrdm_clear_all_prev_pwrst	= omap4_pwrdm_clear_all_prev_pwrst,
	.pwrdm_set_logic_retst	= omap4_pwrdm_set_logic_retst,
	.pwrdm_read_logic_pwrst	= omap4_pwrdm_read_logic_pwrst,
	.pwrdm_read_prev_logic_pwrst	= omap4_pwrdm_read_prev_logic_pwrst,
	.pwrdm_read_logic_retst	= omap4_pwrdm_read_logic_retst,
	.pwrdm_read_mem_pwrst	= omap4_pwrdm_read_mem_pwrst,
	.pwrdm_read_mem_retst	= omap4_pwrdm_read_mem_retst,
	.pwrdm_read_prev_mem_pwrst	= omap4_pwrdm_read_prev_mem_pwrst,
	.pwrdm_set_mem_onst	= omap4_pwrdm_set_mem_onst,
	.pwrdm_set_mem_retst	= omap4_pwrdm_set_mem_retst,
	.pwrdm_wait_transition	= omap4_pwrdm_wait_transition,
};