/*
 * SH7372 clock framework support
 *
 * Copyright (C) 2010 Magnus Damm
 *
 * 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; either version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/sh_clk.h>
#include <linux/clkdev.h>
#include <mach/common.h>

/* SH7372 registers */
#define FRQCRA		IOMEM(0xe6150000)
#define FRQCRB		IOMEM(0xe6150004)
#define FRQCRC		IOMEM(0xe61500e0)
#define FRQCRD		IOMEM(0xe61500e4)
#define VCLKCR1		IOMEM(0xe6150008)
#define VCLKCR2		IOMEM(0xe615000c)
#define VCLKCR3		IOMEM(0xe615001c)
#define FMSICKCR	IOMEM(0xe6150010)
#define FMSOCKCR	IOMEM(0xe6150014)
#define FSIACKCR	IOMEM(0xe6150018)
#define FSIBCKCR	IOMEM(0xe6150090)
#define SUBCKCR		IOMEM(0xe6150080)
#define SPUCKCR		IOMEM(0xe6150084)
#define VOUCKCR		IOMEM(0xe6150088)
#define HDMICKCR	IOMEM(0xe6150094)
#define DSITCKCR	IOMEM(0xe6150060)
#define DSI0PCKCR	IOMEM(0xe6150064)
#define DSI1PCKCR	IOMEM(0xe6150098)
#define PLLC01CR	IOMEM(0xe6150028)
#define PLLC2CR		IOMEM(0xe615002c)
#define RMSTPCR0	IOMEM(0xe6150110)
#define RMSTPCR1	IOMEM(0xe6150114)
#define RMSTPCR2	IOMEM(0xe6150118)
#define RMSTPCR3	IOMEM(0xe615011c)
#define RMSTPCR4	IOMEM(0xe6150120)
#define SMSTPCR0	IOMEM(0xe6150130)
#define SMSTPCR1	IOMEM(0xe6150134)
#define SMSTPCR2	IOMEM(0xe6150138)
#define SMSTPCR3	IOMEM(0xe615013c)
#define SMSTPCR4	IOMEM(0xe6150140)

#define FSIDIVA		0xFE1F8000
#define FSIDIVB		0xFE1F8008

/* Platforms must set frequency on their DV_CLKI pin */
struct clk sh7372_dv_clki_clk = {
};

/* Fixed 32 KHz root clock from EXTALR pin */
static struct clk r_clk = {
	.rate           = 32768,
};

/*
 * 26MHz default rate for the EXTAL1 root input clock.
 * If needed, reset this with clk_set_rate() from the platform code.
 */
struct clk sh7372_extal1_clk = {
	.rate		= 26000000,
};

/*
 * 48MHz default rate for the EXTAL2 root input clock.
 * If needed, reset this with clk_set_rate() from the platform code.
 */
struct clk sh7372_extal2_clk = {
	.rate		= 48000000,
};

/* A fixed divide-by-2 block */
static unsigned long div2_recalc(struct clk *clk)
{
	return clk->parent->rate / 2;
}

static struct sh_clk_ops div2_clk_ops = {
	.recalc		= div2_recalc,
};

/* Divide dv_clki by two */
struct clk sh7372_dv_clki_div2_clk = {
	.ops		= &div2_clk_ops,
	.parent		= &sh7372_dv_clki_clk,
};

/* Divide extal1 by two */
static struct clk extal1_div2_clk = {
	.ops		= &div2_clk_ops,
	.parent		= &sh7372_extal1_clk,
};

/* Divide extal2 by two */
static struct clk extal2_div2_clk = {
	.ops		= &div2_clk_ops,
	.parent		= &sh7372_extal2_clk,
};

/* Divide extal2 by four */
static struct clk extal2_div4_clk = {
	.ops		= &div2_clk_ops,
	.parent		= &extal2_div2_clk,
};

/* PLLC0 and PLLC1 */
static unsigned long pllc01_recalc(struct clk *clk)
{
	unsigned long mult = 1;

	if (__raw_readl(PLLC01CR) & (1 << 14))
		mult = (((__raw_readl(clk->enable_reg) >> 24) & 0x3f) + 1) * 2;

	return clk->parent->rate * mult;
}

static struct sh_clk_ops pllc01_clk_ops = {
	.recalc		= pllc01_recalc,
};

static struct clk pllc0_clk = {
	.ops		= &pllc01_clk_ops,
	.flags		= CLK_ENABLE_ON_INIT,
	.parent		= &extal1_div2_clk,
	.enable_reg	= (void __iomem *)FRQCRC,
};

static struct clk pllc1_clk = {
	.ops		= &pllc01_clk_ops,
	.flags		= CLK_ENABLE_ON_INIT,
	.parent		= &extal1_div2_clk,
	.enable_reg	= (void __iomem *)FRQCRA,
};

/* Divide PLLC1 by two */
static struct clk pllc1_div2_clk = {
	.ops		= &div2_clk_ops,
	.parent		= &pllc1_clk,
};

/* PLLC2 */

/* Indices are important - they are the actual src selecting values */
static struct clk *pllc2_parent[] = {
	[0] = &extal1_div2_clk,
	[1] = &extal2_div2_clk,
	[2] = &sh7372_dv_clki_div2_clk,
};

/* Only multipliers 20 * 2 to 46 * 2 are valid, last entry for CPUFREQ_TABLE_END */
static struct cpufreq_frequency_table pllc2_freq_table[29];

static void pllc2_table_rebuild(struct clk *clk)
{
	int i;

	/* Initialise PLLC2 frequency table */
	for (i = 0; i < ARRAY_SIZE(pllc2_freq_table) - 2; i++) {
		pllc2_freq_table[i].frequency = clk->parent->rate * (i + 20) * 2;
		pllc2_freq_table[i].index = i;
	}

	/* This is a special entry - switching PLL off makes it a repeater */
	pllc2_freq_table[i].frequency = clk->parent->rate;
	pllc2_freq_table[i].index = i;

	pllc2_freq_table[++i].frequency = CPUFREQ_TABLE_END;
	pllc2_freq_table[i].index = i;
}

static unsigned long pllc2_recalc(struct clk *clk)
{
	unsigned long mult = 1;

	pllc2_table_rebuild(clk);

	/*
	 * If the PLL is off, mult == 1, clk->rate will be updated in
	 * pllc2_enable().
	 */
	if (__raw_readl(PLLC2CR) & (1 << 31))
		mult = (((__raw_readl(PLLC2CR) >> 24) & 0x3f) + 1) * 2;

	return clk->parent->rate * mult;
}

static long pllc2_round_rate(struct clk *clk, unsigned long rate)
{
	return clk_rate_table_round(clk, clk->freq_table, rate);
}

static int pllc2_enable(struct clk *clk)
{
	int i;

	__raw_writel(__raw_readl(PLLC2CR) | 0x80000000, PLLC2CR);

	for (i = 0; i < 100; i++)
		if (__raw_readl(PLLC2CR) & 0x80000000) {
			clk->rate = pllc2_recalc(clk);
			return 0;
		}

	pr_err("%s(): timeout!\n", __func__);