/*
 * AM33XX Powerdomain control
 *
 * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
 *
 * Derived from mach-omap2/powerdomain44xx.c written by 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 as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

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

#include <plat/prcm.h>

#include "powerdomain.h"
#include "prm33xx.h"
#include "prm-regbits-33xx.h"


static int am33xx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
{
	am33xx_prm_rmw_reg_bits(OMAP_POWERSTATE_MASK,
				(pwrst << OMAP_POWERSTATE_SHIFT),
				pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
	return 0;
}

static int am33xx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs,  pwrdm->pwrstctrl_offs);
	v &= OMAP_POWERSTATE_MASK;
	v >>= OMAP_POWERSTATE_SHIFT;

	return v;
}

static int am33xx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
	v &= OMAP_POWERSTATEST_MASK;
	v >>= OMAP_POWERSTATEST_SHIFT;

	return v;
}

static int am33xx_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
	v &= AM33XX_LASTPOWERSTATEENTERED_MASK;
	v >>= AM33XX_LASTPOWERSTATEENTERED_SHIFT;

	return v;
}

static int am33xx_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
{
	am33xx_prm_rmw_reg_bits(AM33XX_LOWPOWERSTATECHANGE_MASK,
				(1 << AM33XX_LOWPOWERSTATECHANGE_SHIFT),
				pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
	return 0;
}

static int am33xx_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
{
	am33xx_prm_rmw_reg_bits(AM33XX_LASTPOWERSTATEENTERED_MASK,
				AM33XX_LASTPOWERSTATEENTERED_MASK,
				pwrdm->prcm_offs, pwrdm->pwrstst_offs);
	return 0;
}

static int am33xx_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
{
	u32 m;

	m = pwrdm->logicretstate_mask;
	if (!m)
		return -EINVAL;

	am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
				pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);

	return 0;
}

static int am33xx_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
{
	u32 v;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
	v &= AM33XX_LOGICSTATEST_MASK;
	v >>= AM33XX_LOGICSTATEST_SHIFT;

	return v;
}

static int am33xx_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
{
	u32 v, m;

	m = pwrdm->logicretstate_mask;
	if (!m)
		return -EINVAL;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
	v &= m;
	v >>= __ffs(m);

	return v;
}

static int am33xx_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
		u8 pwrst)
{
	u32 m;

	m = pwrdm->mem_on_mask[bank];
	if (!m)
		return -EINVAL;

	am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
				pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);

	return 0;
}

static int am33xx_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
					u8 pwrst)
{
	u32 m;

	m = pwrdm->mem_ret_mask[bank];
	if (!m)
		return -EINVAL;

	am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
				pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);

	return 0;
}

static int am33xx_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
{
	u32 m, v;

	m = pwrdm->mem_pwrst_mask[bank];
	if (!m)
		return -EINVAL;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
	v &= m;
	v >>= __ffs(m);

	return v;
}

static int am33xx_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
{
	u32 m, v;

	m = pwrdm->mem_retst_mask[bank];
	if (!m)
		return -EINVAL;

	v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
	v &= m;
	v >>= __ffs(m);

	return v;
}

static int am33xx_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 ((am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs)
			& 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 am33xx_pwrdm_operations = {
	.pwrdm_set_next_pwrst		= am33xx_pwrdm_set_next_pwrst,
	.pwrdm_read_next_pwrst		= am33xx_pwrdm_read_next_pwrst,
	.pwrdm_read_pwrst		= am33xx_pwrdm_read_pwrst,
	.pwrdm_read_prev_pwrst		= am33xx_pwrdm_read_prev_pwrst,
	.pwrdm_set_logic_retst		= am33xx_pwrdm_set_logic_retst,
	.pwrdm_read_logic_pwrst		= am33xx_pwrdm_read_logic_pwrst,
	.pwrdm_read_logic_retst		= am33xx_pwrdm_read_logic_retst,
	.pwrdm_clear_all_prev_pwrst	= am33xx_pwrdm_clear_all_prev_pwrst,
	.pwrdm_set_lowpwrstchange	= am33xx_pwrdm_set_lowpwrstchange,
	.pwrdm_read_mem_pwrst		= am33xx_pwrdm_read_mem_pwrst,
	.pwrdm_read_mem_retst		= am33xx_pwrdm_read_mem_retst,
	.pwrdm_set_mem_onst		= am33xx_pwrdm_set_mem_onst,
	.pwrdm_set_mem_retst		= am33xx_pwrdm_set_mem_retst,
	.pwrdm_wait_transition		= am33xx_pwrdm_wait_transition,
};