arch/arm/mach-exynos/clock.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2010 Samsung Electronics
 * Minkyu Kang <mk7.kang@samsung.com>
 */

#include <common.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/clk.h>
#include <asm/arch/periph.h>

#define PLL_DIV_1024	1024
#define PLL_DIV_65535	65535
#define PLL_DIV_65536	65536
/* *
 * This structure is to store the src bit, div bit and prediv bit
 * positions of the peripheral clocks of the src and div registers
 */
struct clk_bit_info {
	enum periph_id id;
	int32_t src_mask;
	int32_t div_mask;
	int32_t prediv_mask;
	int8_t src_bit;
	int8_t div_bit;
	int8_t prediv_bit;
};

static struct clk_bit_info exynos5_bit_info[] = {
	/* periph id		s_mask	d_mask	p_mask	s_bit	d_bit	p_bit */
	{PERIPH_ID_UART0,	0xf,	0xf,	-1,	0,	0,	-1},
	{PERIPH_ID_UART1,	0xf,	0xf,	-1,	4,	4,	-1},
	{PERIPH_ID_UART2,	0xf,	0xf,	-1,	8,	8,	-1},
	{PERIPH_ID_UART3,	0xf,	0xf,	-1,	12,	12,	-1},
	{PERIPH_ID_I2C0,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C1,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C2,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C3,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C4,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C5,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C6,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_I2C7,	-1,	0x7,	0x7,	-1,	24,	0},
	{PERIPH_ID_SPI0,	0xf,	0xf,	0xff,	16,	0,	8},
	{PERIPH_ID_SPI1,	0xf,	0xf,	0xff,	20,	16,	24},
	{PERIPH_ID_SPI2,	0xf,	0xf,	0xff,	24,	0,	8},
	{PERIPH_ID_SDMMC0,	0xf,	0xf,	0xff,	0,	0,	8},
	{PERIPH_ID_SDMMC1,	0xf,	0xf,	0xff,	4,	16,	24},
	{PERIPH_ID_SDMMC2,	0xf,	0xf,	0xff,	8,	0,	8},
	{PERIPH_ID_SDMMC3,	0xf,	0xf,	0xff,	12,	16,	24},
	{PERIPH_ID_I2S0,	0xf,	0xf,	0xff,	0,	0,	4},
	{PERIPH_ID_I2S1,	0xf,	0xf,	0xff,	4,	12,	16},
	{PERIPH_ID_SPI3,	0xf,	0xf,	0xff,	0,	0,	4},
	{PERIPH_ID_SPI4,	0xf,	0xf,	0xff,	4,	12,	16},
	{PERIPH_ID_SDMMC4,	0xf,	0xf,	0xff,	16,	0,	8},
	{PERIPH_ID_PWM0,	0xf,	0xf,	-1,	24,	0,	-1},
	{PERIPH_ID_PWM1,	0xf,	0xf,	-1,	24,	0,	-1},
	{PERIPH_ID_PWM2,	0xf,	0xf,	-1,	24,	0,	-1},
	{PERIPH_ID_PWM3,	0xf,	0xf,	-1,	24,	0,	-1},
	{PERIPH_ID_PWM4,	0xf,	0xf,	-1,	24,	0,	-1},

	{PERIPH_ID_NONE,	-1,	-1,	-1,	-1,	-1,	-1},
};

static struct clk_bit_info exynos542x_bit_info[] = {
	/* periph id		s_mask	d_mask	p_mask	s_bit	d_bit	p_bit */
	{PERIPH_ID_UART0,	0xf,	0xf,	-1,	4,	8,	-1},
	{PERIPH_ID_UART1,	0xf,	0xf,	-1,	8,	12,	-1},
	{PERIPH_ID_UART2,	0xf,	0xf,	-1,	12,	16,	-1},
	{PERIPH_ID_UART3,	0xf,	0xf,	-1,	16,	20,	-1},
	{PERIPH_ID_I2C0,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C1,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C2,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C3,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C4,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C5,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C6,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C7,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_SPI0,	0xf,	0xf,	0xff,	20,	20,	8},
	{PERIPH_ID_SPI1,	0xf,	0xf,	0xff,	24,	24,	16},
	{PERIPH_ID_SPI2,	0xf,	0xf,	0xff,	28,	28,	24},
	{PERIPH_ID_SDMMC0,	0x7,	0x3ff,	-1,	8,	0,	-1},
	{PERIPH_ID_SDMMC1,	0x7,	0x3ff,	-1,	12,	10,	-1},
	{PERIPH_ID_SDMMC2,	0x7,	0x3ff,	-1,	16,	20,	-1},
	{PERIPH_ID_I2C8,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2C9,	-1,	0x3f,	-1,	-1,	8,	-1},
	{PERIPH_ID_I2S0,	0xf,	0xf,	0xff,	0,	0,	4},
	{PERIPH_ID_I2S1,	0xf,	0xf,	0xff,	4,	12,	16},
	{PERIPH_ID_SPI3,	0xf,	0xf,	0xff,	12,	16,	0},
	{PERIPH_ID_SPI4,	0xf,	0xf,	0xff,	16,	20,	8},
	{PERIPH_ID_PWM0,	0xf,	0xf,	-1,	24,	28,	-1},
	{PERIPH_ID_PWM1,	0xf,	0xf,	-1,	24,	28,	-1},
	{PERIPH_ID_PWM2,	0xf,	0xf,	-1,	24,	28,	-1},
	{PERIPH_ID_PWM3,	0xf,	0xf,	-1,	24,	28,	-1},
	{PERIPH_ID_PWM4,	0xf,	0xf,	-1,	24,	28,	-1},
	{PERIPH_ID_I2C10,	-1,	0x3f,	-1,	-1,	8,	-1},

	{PERIPH_ID_NONE,	-1,	-1,	-1,	-1,	-1,	-1},
};

/* Epll Clock division values to achive different frequency output */
static struct set_epll_con_val exynos5_epll_div[] = {
	{ 192000000, 0, 48, 3, 1, 0 },
	{ 180000000, 0, 45, 3, 1, 0 },
	{  73728000, 1, 73, 3, 3, 47710 },
	{  67737600, 1, 90, 4, 3, 20762 },
	{  49152000, 0, 49, 3, 3, 9961 },
	{  45158400, 0, 45, 3, 3, 10381 },
	{ 180633600, 0, 45, 3, 1, 10381 }
};

/* exynos: return pll clock frequency */
static int exynos_get_pll_clk(int pllreg, unsigned int r, unsigned int k)
{
	unsigned long m, p, s = 0, mask, fout;
	unsigned int div;
	unsigned int freq;
	/*
	 * APLL_CON: MIDV [25:16]
	 * MPLL_CON: MIDV [25:16]
	 * EPLL_CON: MIDV [24:16]
	 * VPLL_CON: MIDV [24:16]
	 * BPLL_CON: MIDV [25:16]: Exynos5
	 */
	if (pllreg == APLL || pllreg == MPLL || pllreg == BPLL ||
	    pllreg == SPLL)
		mask = 0x3ff;
	else
		mask = 0x1ff;

	m = (r >> 16) & mask;

	/* PDIV [13:8] */
	p = (r >> 8) & 0x3f;
	/* SDIV [2:0] */
	s = r & 0x7;

	freq = CONFIG_SYS_CLK_FREQ;

	if (pllreg == EPLL || pllreg == RPLL) {
		k = k & 0xffff;
		/* FOUT = (MDIV + K / 65536) * FIN / (PDIV * 2^SDIV) */
		fout = (m + k / PLL_DIV_65536) * (freq / (p * (1 << s)));
	} else if (pllreg == VPLL) {
		k = k & 0xfff;

		/*
		 * Exynos4210
		 * FOUT = (MDIV + K / 1024) * FIN / (PDIV * 2^SDIV)
		 *
		 * Exynos4412
		 * FOUT = (MDIV + K / 65535) * FIN / (PDIV * 2^SDIV)
		 *
		 * Exynos5250
		 * FOUT = (MDIV + K / 65536) * FIN / (PDIV * 2^SDIV)
		 */
		if (proid_is_exynos4210())
			div = PLL_DIV_1024;
		else if (proid_is_exynos4412())
			div = PLL_DIV_65535;
		else if (proid_is_exynos5250() || proid_is_exynos5420() ||
			 proid_is_exynos5422())
			div = PLL_DIV_65536;
		else
			return 0;

		fout = (m + k / div) * (freq / (p * (1 << s)));
	} else {
		/*
		 * Exynos4412 / Exynos5250
		 * FOUT = MDIV * FIN / (PDIV * 2^SDIV)
		 *
		 * Exynos4210
		 * FOUT = MDIV * FIN / (PDIV * 2^(SDIV-1))
		 */
		if (proid_is_exynos4210())
			fout = m * (freq / (p * (1 << (s - 1))));
		else
			fout = m * (freq / (p * (1 << s)));
	}
	return fout;
}

/* exynos4: return pll clock frequency */
static unsigned long exynos4_get_pll_clk(int pllreg)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long r, k = 0;

	switch (pllreg) {
	case APLL:
		r = readl(&clk->apll_con0);
		break;
	case MPLL:
		r = readl(&clk->mpll_con0);
		break;
	case EPLL:
		r = readl(&clk->epll_con0);
		k = readl(&clk->epll_con1);
		break;
	case VPLL:
		r = readl(&clk->vpll_con0);
		k = readl(&clk->vpll_con1);
		break;
	default:
		printf("Unsupported PLL (%d)\n", pllreg);
		return 0;
	}

	return exynos_get_pll_clk(pllreg, r, k);
}

/* exynos4x12: return pll clock frequency */
static unsigned long exynos4x12_get_pll_clk(int pllreg)
{
	struct exynos4x12_clock *clk =
		(struct exynos4x12_clock *)samsung_get_base_clock();
	unsigned long r, k = 0;

	switch (pllreg) {
	case APLL:
		r = readl(&clk->apll_con0);
		break;
	case MPLL:
		r = readl(&clk->mpll_con0);
		break;
	case EPLL:
		r = readl(&clk->epll_con0);
		k = readl(&clk->epll_con1);
		break;
	case VPLL:
		r = readl(&clk->vpll_con0);
		k = readl(&clk->vpll_con1);
		break;
	default:
		printf("Unsupported PLL (%d)\n", pllreg);
		return 0;
	}

	return exynos_get_pll_clk(pllreg, r, k);
}

/* exynos5: return pll clock frequency */
static unsigned long exynos5_get_pll_clk(int pllreg)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned long r, k = 0, fout;
	unsigned int pll_div2_sel, fout_sel;

	switch (pllreg) {
	case APLL:
		r = readl(&clk->apll_con0);
		break;
	case MPLL:
		r = readl(&clk->mpll_con0);
		break;
	case EPLL:
		r = readl(&clk->epll_con0);
		k = readl(&clk->epll_con1);
		break;
	case VPLL:
		r = readl(&clk->vpll_con0);
		k = readl(&clk->vpll_con1);
		break;
	case BPLL:
		r = readl(&clk->bpll_con0);
		break;
	default:
		printf("Unsupported PLL (%d)\n", pllreg);
		return 0;
	}

	fout = exynos_get_pll_clk(pllreg, r, k);

	/* According to the user manual, in EVT1 MPLL and BPLL always gives
	 * 1.6GHz clock, so divide by 2 to get 800MHz MPLL clock.*/
	if (pllreg == MPLL || pllreg == BPLL) {
		pll_div2_sel = readl(&clk->pll_div2_sel);

		switch (pllreg) {
		case MPLL:
			fout_sel = (pll_div2_sel >> MPLL_FOUT_SEL_SHIFT)
					& MPLL_FOUT_SEL_MASK;
			break;
		case BPLL:
			fout_sel = (pll_div2_sel >> BPLL_FOUT_SEL_SHIFT)
					& BPLL_FOUT_SEL_MASK;
			break;
		default:
			fout_sel = -1;
			break;
		}

		if (fout_sel == 0)
			fout /= 2;
	}

	return fout;
}

/* exynos542x: return pll clock frequency */
static unsigned long exynos542x_get_pll_clk(int pllreg)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned long r, k = 0;

	switch (pllreg) {
	case APLL:
		r = readl(&clk->apll_con0);
		break;
	case MPLL:
		r = readl(&clk->mpll_con0);
		break;
	case EPLL:
		r = readl(&clk->epll_con0);
		k = readl(&clk->epll_con1);
		break;
	case VPLL:
		r = readl(&clk->vpll_con0);
		k = readl(&clk->vpll_con1);
		break;
	case BPLL:
		r = readl(&clk->bpll_con0);
		break;
	case RPLL:
		r = readl(&clk->rpll_con0);
		k = readl(&clk->rpll_con1);
		break;
	case SPLL:
		r = readl(&clk->spll_con0);
		break;
	default:
		printf("Unsupported PLL (%d)\n", pllreg);
		return 0;
	}

	return exynos_get_pll_clk(pllreg, r, k);
}

static struct clk_bit_info *get_clk_bit_info(int peripheral)
{
	int i;
	struct clk_bit_info *info;

	if (proid_is_exynos5420() || proid_is_exynos5422())
		info = exynos542x_bit_info;
	else
		info = exynos5_bit_info;

	for (i = 0; info[i].id != PERIPH_ID_NONE; i++) {
		if (info[i].id == peripheral)
			break;
	}

	if (info[i].id == PERIPH_ID_NONE)
		debug("ERROR: Peripheral ID %d not found\n", peripheral);

	return &info[i];
}

static unsigned long exynos5_get_periph_rate(int peripheral)
{
	struct clk_bit_info *bit_info = get_clk_bit_info(peripheral);
	unsigned long sclk = 0;
	unsigned int src = 0, div = 0, sub_div = 0;
	struct exynos5_clock *clk =
			(struct exynos5_clock *)samsung_get_base_clock();

	switch (peripheral) {
	case PERIPH_ID_UART0:
	case PERIPH_ID_UART1:
	case PERIPH_ID_UART2:
	case PERIPH_ID_UART3:
		src = readl(&clk->src_peric0);
		div = readl(&clk->div_peric0);
		break;
	case PERIPH_ID_PWM0:
	case PERIPH_ID_PWM1:
	case PERIPH_ID_PWM2:
	case PERIPH_ID_PWM3:
	case PERIPH_ID_PWM4:
		src = readl(&clk->src_peric0);
		div = readl(&clk->div_peric3);
		break;
	case PERIPH_ID_I2S0:
		src = readl(&clk->src_mau);
		div = sub_div = readl(&clk->div_mau);
	case PERIPH_ID_SPI0:
	case PERIPH_ID_SPI1:
		src = readl(&clk->src_peric1);
		div = sub_div = readl(&clk->div_peric1);
		break;
	case PERIPH_ID_SPI2:
		src = readl(&clk->src_peric1);
		div = sub_div = readl(&clk->div_peric2);
		break;
	case PERIPH_ID_SPI3:
	case PERIPH_ID_SPI4:
		src = readl(&clk->sclk_src_isp);
		div = sub_div = readl(&clk->sclk_div_isp);
		break;
	case PERIPH_ID_SDMMC0:
	case PERIPH_ID_SDMMC1:
		src = readl(&clk->src_fsys);
		div = sub_div = readl(&clk->div_fsys1);
		break;
	case PERIPH_ID_SDMMC2:
	case PERIPH_ID_SDMMC3:
		src = readl(&clk->src_fsys);
		div = sub_div = readl(&clk->div_fsys2);
		break;
	case PERIPH_ID_I2C0:
	case PERIPH_ID_I2C1:
	case PERIPH_ID_I2C2:
	case PERIPH_ID_I2C3:
	case PERIPH_ID_I2C4:
	case PERIPH_ID_I2C5:
	case PERIPH_ID_I2C6:
	case PERIPH_ID_I2C7:
		src = EXYNOS_SRC_MPLL;
		div = readl(&clk->div_top1);
		sub_div = readl(&clk->div_top0);
		break;
	default:
		debug("%s: invalid peripheral %d", __func__, peripheral);
		return -1;
	};

	if (bit_info->src_bit >= 0)
		src = (src >> bit_info->src_bit) & bit_info->src_mask;

	switch (src) {
	case EXYNOS_SRC_MPLL:
		sclk = exynos5_get_pll_clk(MPLL);
		break;
	case EXYNOS_SRC_EPLL:
		sclk = exynos5_get_pll_clk(EPLL);
		break;
	case EXYNOS_SRC_VPLL:
		sclk = exynos5_get_pll_clk(VPLL);
		break;
	default:
		debug("%s: EXYNOS_SRC %d not supported\n", __func__, src);
		return 0;
	}

	/* Clock divider ratio for this peripheral */
	if (bit_info->div_bit >= 0)
		div = (div >> bit_info->div_bit) & bit_info->div_mask;

	/* Clock pre-divider ratio for this peripheral */
	if (bit_info->prediv_bit >= 0)
		sub_div = (sub_div >> bit_info->prediv_bit)
			  & bit_info->prediv_mask;

	/* Calculate and return required clock rate */
	return (sclk / (div + 1)) / (sub_div + 1);
}

static unsigned long exynos542x_get_periph_rate(int peripheral)
{
	struct clk_bit_info *bit_info = get_clk_bit_info(peripheral);
	unsigned long sclk = 0;
	unsigned int src = 0, div = 0, sub_div = 0;
	struct exynos5420_clock *clk =
			(struct exynos5420_clock *)samsung_get_base_clock();

	switch (peripheral) {
	case PERIPH_ID_UART0:
	case PERIPH_ID_UART1:
	case PERIPH_ID_UART2:
	case PERIPH_ID_UART3:
	case PERIPH_ID_PWM0:
	case PERIPH_ID_PWM1:
	case PERIPH_ID_PWM2:
	case PERIPH_ID_PWM3:
	case PERIPH_ID_PWM4:
		src = readl(&clk->src_peric0);
		div = readl(&clk->div_peric0);
		break;
	case PERIPH_ID_SPI0:
	case PERIPH_ID_SPI1:
	case PERIPH_ID_SPI2:
		src = readl(&clk->src_peric1);
		div = readl(&clk->div_peric1);
		sub_div = readl(&clk->div_peric4);
		break;
	case PERIPH_ID_SPI3:
	case PERIPH_ID_SPI4:
		src = readl(&clk->src_isp);
		div = readl(&clk->div_isp1);
		sub_div = readl(&clk->div_isp1);
		break;
	case PERIPH_ID_SDMMC0:
	case PERIPH_ID_SDMMC1:
	case PERIPH_ID_SDMMC2:
	case PERIPH_ID_SDMMC3:
		src = readl(&clk->src_fsys);
		div = readl(&clk->div_fsys1);
		break;
	case PERIPH_ID_I2C0:
	case PERIPH_ID_I2C1:
	case PERIPH_ID_I2C2:
	case PERIPH_ID_I2C3:
	case PERIPH_ID_I2C4:
	case PERIPH_ID_I2C5:
	case PERIPH_ID_I2C6:
	case PERIPH_ID_I2C7:
	case PERIPH_ID_I2C8:
	case PERIPH_ID_I2C9:
	case PERIPH_ID_I2C10:
		src = EXYNOS542X_SRC_MPLL;
		div = readl(&clk->div_top1);
		break;
	default:
		debug("%s: invalid peripheral %d", __func__, peripheral);
		return -1;
	};

	if (bit_info->src_bit >= 0)
		src = (src >> bit_info->src_bit) & bit_info->src_mask;

	switch (src) {
	case EXYNOS542X_SRC_MPLL:
		sclk = exynos542x_get_pll_clk(MPLL);
		break;
	case EXYNOS542X_SRC_SPLL:
		sclk = exynos542x_get_pll_clk(SPLL);
		break;
	case EXYNOS542X_SRC_EPLL:
		sclk = exynos542x_get_pll_clk(EPLL);
		break;
	case EXYNOS542X_SRC_RPLL:
		sclk = exynos542x_get_pll_clk(RPLL);
		break;
	default:
		debug("%s: EXYNOS542X_SRC %d not supported", __func__, src);
		return 0;
	}

	/* Clock divider ratio for this peripheral */
	if (bit_info->div_bit >= 0)
		div = (div >> bit_info->div_bit) & bit_info->div_mask;

	/* Clock pre-divider ratio for this peripheral */
	if (bit_info->prediv_bit >= 0)
		sub_div = (sub_div >> bit_info->prediv_bit)
			  & bit_info->prediv_mask;

	/* Calculate and return required clock rate */
	return (sclk / (div + 1)) / (sub_div + 1);
}

unsigned long clock_get_periph_rate(int peripheral)
{
	if (cpu_is_exynos5()) {
		if (proid_is_exynos5420() || proid_is_exynos5422())
			return exynos542x_get_periph_rate(peripheral);
		return exynos5_get_periph_rate(peripheral);
	} else {
		return 0;
	}
}

/* exynos4: return ARM clock frequency */
static unsigned long exynos4_get_arm_clk(void)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long div;
	unsigned long armclk;
	unsigned int core_ratio;
	unsigned int core2_ratio;

	div = readl(&clk->div_cpu0);

	/* CORE_RATIO: [2:0], CORE2_RATIO: [30:28] */
	core_ratio = (div >> 0) & 0x7;
	core2_ratio = (div >> 28) & 0x7;

	armclk = get_pll_clk(APLL) / (core_ratio + 1);
	armclk /= (core2_ratio + 1);

	return armclk;
}

/* exynos4x12: return ARM clock frequency */
static unsigned long exynos4x12_get_arm_clk(void)
{
	struct exynos4x12_clock *clk =
		(struct exynos4x12_clock *)samsung_get_base_clock();
	unsigned long div;
	unsigned long armclk;
	unsigned int core_ratio;
	unsigned int core2_ratio;

	div = readl(&clk->div_cpu0);

	/* CORE_RATIO: [2:0], CORE2_RATIO: [30:28] */
	core_ratio = (div >> 0) & 0x7;
	core2_ratio = (div >> 28) & 0x7;

	armclk = get_pll_clk(APLL) / (core_ratio + 1);
	armclk /= (core2_ratio + 1);

	return armclk;
}

/* exynos5: return ARM clock frequency */
static unsigned long exynos5_get_arm_clk(void)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned long div;
	unsigned long armclk;
	unsigned int arm_ratio;
	unsigned int arm2_ratio;

	div = readl(&clk->div_cpu0);

	/* ARM_RATIO: [2:0], ARM2_RATIO: [30:28] */
	arm_ratio = (div >> 0) & 0x7;
	arm2_ratio = (div >> 28) & 0x7;

	armclk = get_pll_clk(APLL) / (arm_ratio + 1);
	armclk /= (arm2_ratio + 1);

	return armclk;
}

/* exynos4: return pwm clock frequency */
static unsigned long exynos4_get_pwm_clk(void)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long pclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	if (s5p_get_cpu_rev() == 0) {
		/*
		 * CLK_SRC_PERIL0
		 * PWM_SEL [27:24]
		 */
		sel = readl(&clk->src_peril0);
		sel = (sel >> 24) & 0xf;

		if (sel == 0x6)
			sclk = get_pll_clk(MPLL);
		else if (sel == 0x7)
			sclk = get_pll_clk(EPLL);
		else if (sel == 0x8)
			sclk = get_pll_clk(VPLL);
		else
			return 0;

		/*
		 * CLK_DIV_PERIL3
		 * PWM_RATIO [3:0]
		 */
		ratio = readl(&clk->div_peril3);
		ratio = ratio & 0xf;
	} else if (s5p_get_cpu_rev() == 1) {
		sclk = get_pll_clk(MPLL);
		ratio = 8;
	} else
		return 0;

	pclk = sclk / (ratio + 1);

	return pclk;
}

/* exynos4x12: return pwm clock frequency */
static unsigned long exynos4x12_get_pwm_clk(void)
{
	unsigned long pclk, sclk;
	unsigned int ratio;

	sclk = get_pll_clk(MPLL);
	ratio = 8;

	pclk = sclk / (ratio + 1);

	return pclk;
}

/* exynos4: return uart clock frequency */
static unsigned long exynos4_get_uart_clk(int dev_index)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long uclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_PERIL0
	 * UART0_SEL [3:0]
	 * UART1_SEL [7:4]
	 * UART2_SEL [8:11]
	 * UART3_SEL [12:15]
	 * UART4_SEL [16:19]
	 * UART5_SEL [23:20]
	 */
	sel = readl(&clk->src_peril0);
	sel = (sel >> (dev_index << 2)) & 0xf;

	if (sel == 0x6)
		sclk = get_pll_clk(MPLL);
	else if (sel == 0x7)
		sclk = get_pll_clk(EPLL);
	else if (sel == 0x8)
		sclk = get_pll_clk(VPLL);
	else
		return 0;

	/*
	 * CLK_DIV_PERIL0
	 * UART0_RATIO [3:0]
	 * UART1_RATIO [7:4]
	 * UART2_RATIO [8:11]
	 * UART3_RATIO [12:15]
	 * UART4_RATIO [16:19]
	 * UART5_RATIO [23:20]
	 */
	ratio = readl(&clk->div_peril0);
	ratio = (ratio >> (dev_index << 2)) & 0xf;

	uclk = sclk / (ratio + 1);

	return uclk;
}

/* exynos4x12: return uart clock frequency */
static unsigned long exynos4x12_get_uart_clk(int dev_index)
{
	struct exynos4x12_clock *clk =
		(struct exynos4x12_clock *)samsung_get_base_clock();
	unsigned long uclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_PERIL0
	 * UART0_SEL [3:0]
	 * UART1_SEL [7:4]
	 * UART2_SEL [8:11]
	 * UART3_SEL [12:15]
	 * UART4_SEL [16:19]
	 */
	sel = readl(&clk->src_peril0);
	sel = (sel >> (dev_index << 2)) & 0xf;

	if (sel == 0x6)
		sclk = get_pll_clk(MPLL);
	else if (sel == 0x7)
		sclk = get_pll_clk(EPLL);
	else if (sel == 0x8)
		sclk = get_pll_clk(VPLL);
	else
		return 0;

	/*
	 * CLK_DIV_PERIL0
	 * UART0_RATIO [3:0]
	 * UART1_RATIO [7:4]
	 * UART2_RATIO [8:11]
	 * UART3_RATIO [12:15]
	 * UART4_RATIO [16:19]
	 */
	ratio = readl(&clk->div_peril0);
	ratio = (ratio >> (dev_index << 2)) & 0xf;

	uclk = sclk / (ratio + 1);

	return uclk;
}

static unsigned long exynos4_get_mmc_clk(int dev_index)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long uclk, sclk;
	unsigned int sel, ratio, pre_ratio;
	int shift = 0;

	sel = readl(&clk->src_fsys);
	sel = (sel >> (dev_index << 2)) & 0xf;

	if (sel == 0x6)
		sclk = get_pll_clk(MPLL);
	else if (sel == 0x7)
		sclk = get_pll_clk(EPLL);
	else if (sel == 0x8)
		sclk = get_pll_clk(VPLL);
	else
		return 0;

	switch (dev_index) {
	case 0:
	case 1:
		ratio = readl(&clk->div_fsys1);
		pre_ratio = readl(&clk->div_fsys1);
		break;
	case 2:
	case 3:
		ratio = readl(&clk->div_fsys2);
		pre_ratio = readl(&clk->div_fsys2);
		break;
	case 4:
		ratio = readl(&clk->div_fsys3);
		pre_ratio = readl(&clk->div_fsys3);
		break;
	default:
		return 0;
	}

	if (dev_index == 1 || dev_index == 3)
		shift = 16;

	ratio = (ratio >> shift) & 0xf;
	pre_ratio = (pre_ratio >> (shift + 8)) & 0xff;
	uclk = (sclk / (ratio + 1)) / (pre_ratio + 1);

	return uclk;
}

/* exynos4: set the mmc clock */
static void exynos4_set_mmc_clk(int dev_index, unsigned int div)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned int addr, clear_bit, set_bit;

	/*
	 * CLK_DIV_FSYS1
	 * MMC0_PRE_RATIO [15:8], MMC1_PRE_RATIO [31:24]
	 * CLK_DIV_FSYS2
	 * MMC2_PRE_RATIO [15:8], MMC3_PRE_RATIO [31:24]
	 * CLK_DIV_FSYS3
	 * MMC4_RATIO [3:0]
	 */
	if (dev_index < 2) {
		addr = (unsigned int)&clk->div_fsys1;
		clear_bit = MASK_PRE_RATIO(dev_index);
		set_bit = SET_PRE_RATIO(dev_index, div);
	} else if (dev_index == 4) {
		addr = (unsigned int)&clk->div_fsys3;
		dev_index -= 4;
		/* MMC4 is controlled with the MMC4_RATIO value */
		clear_bit = MASK_RATIO(dev_index);
		set_bit = SET_RATIO(dev_index, div);
	} else {
		addr = (unsigned int)&clk->div_fsys2;
		dev_index -= 2;
		clear_bit = MASK_PRE_RATIO(dev_index);
		set_bit = SET_PRE_RATIO(dev_index, div);
	}

	clrsetbits_le32(addr, clear_bit, set_bit);
}

/* exynos5: set the mmc clock */
static void exynos5_set_mmc_clk(int dev_index, unsigned int div)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned int addr;

	/*
	 * CLK_DIV_FSYS1
	 * MMC0_PRE_RATIO [15:8], MMC1_PRE_RATIO [31:24]
	 * CLK_DIV_FSYS2
	 * MMC2_PRE_RATIO [15:8], MMC3_PRE_RATIO [31:24]
	 */
	if (dev_index < 2) {
		addr = (unsigned int)&clk->div_fsys1;
	} else {
		addr = (unsigned int)&clk->div_fsys2;
		dev_index -= 2;
	}

	clrsetbits_le32(addr, 0xff << ((dev_index << 4) + 8),
			(div & 0xff) << ((dev_index << 4) + 8));
}

/* exynos5: set the mmc clock */
static void exynos5420_set_mmc_clk(int dev_index, unsigned int div)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned int addr;
	unsigned int shift;

	/*
	 * CLK_DIV_FSYS1
	 * MMC0_RATIO [9:0]
	 * MMC1_RATIO [19:10]
	 * MMC2_RATIO [29:20]
	 */
	addr = (unsigned int)&clk->div_fsys1;
	shift = dev_index * 10;

	clrsetbits_le32(addr, 0x3ff << shift, (div & 0x3ff) << shift);
}

/* get_lcd_clk: return lcd clock frequency */
static unsigned long exynos4_get_lcd_clk(void)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long pclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_LCD0
	 * FIMD0_SEL [3:0]
	 */
	sel = readl(&clk->src_lcd0);
	sel = sel & 0xf;

	/*
	 * 0x6: SCLK_MPLL
	 * 0x7: SCLK_EPLL
	 * 0x8: SCLK_VPLL
	 */
	if (sel == 0x6)
		sclk = get_pll_clk(MPLL);
	else if (sel == 0x7)
		sclk = get_pll_clk(EPLL);
	else if (sel == 0x8)
		sclk = get_pll_clk(VPLL);
	else
		return 0;

	/*
	 * CLK_DIV_LCD0
	 * FIMD0_RATIO [3:0]
	 */
	ratio = readl(&clk->div_lcd0);
	ratio = ratio & 0xf;

	pclk = sclk / (ratio + 1);

	return pclk;
}

/* get_lcd_clk: return lcd clock frequency */
static unsigned long exynos5_get_lcd_clk(void)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned long pclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_LCD0
	 * FIMD0_SEL [3:0]
	 */
	sel = readl(&clk->src_disp1_0);
	sel = sel & 0xf;

	/*
	 * 0x6: SCLK_MPLL
	 * 0x7: SCLK_EPLL
	 * 0x8: SCLK_VPLL
	 */
	if (sel == 0x6)
		sclk = get_pll_clk(MPLL);
	else if (sel == 0x7)
		sclk = get_pll_clk(EPLL);
	else if (sel == 0x8)
		sclk = get_pll_clk(VPLL);
	else
		return 0;

	/*
	 * CLK_DIV_LCD0
	 * FIMD0_RATIO [3:0]
	 */
	ratio = readl(&clk->div_disp1_0);
	ratio = ratio & 0xf;

	pclk = sclk / (ratio + 1);

	return pclk;
}

static unsigned long exynos5420_get_lcd_clk(void)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned long pclk, sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_DISP10
	 * FIMD1_SEL [4]
	 * 0: SCLK_RPLL
	 * 1: SCLK_SPLL
	 */
	sel = readl(&clk->src_disp10);
	sel &= (1 << 4);

	if (sel)
		sclk = get_pll_clk(SPLL);
	else
		sclk = get_pll_clk(RPLL);

	/*
	 * CLK_DIV_DISP10
	 * FIMD1_RATIO [3:0]
	 */
	ratio = readl(&clk->div_disp10);
	ratio = ratio & 0xf;

	pclk = sclk / (ratio + 1);

	return pclk;
}

static unsigned long exynos5800_get_lcd_clk(void)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned long sclk;
	unsigned int sel;
	unsigned int ratio;

	/*
	 * CLK_SRC_DISP10
	 * CLKMUX_FIMD1 [6:4]
	 */
	sel = (readl(&clk->src_disp10) >> 4) & 0x7;

	if (sel) {
		/*
		 * Mapping of CLK_SRC_DISP10 CLKMUX_FIMD1 [6:4] values into
		 * PLLs. The first element is a placeholder to bypass the
		 * default settig.
		 */
		const int reg_map[] = {0, CPLL, DPLL, MPLL, SPLL, IPLL, EPLL,
									RPLL};
		sclk = get_pll_clk(reg_map[sel]);
	} else
		sclk = CONFIG_SYS_CLK_FREQ;
	/*
	 * CLK_DIV_DISP10
	 * FIMD1_RATIO [3:0]
	 */
	ratio = readl(&clk->div_disp10) & 0xf;

	return sclk / (ratio + 1);
}

void exynos4_set_lcd_clk(void)
{
	struct exynos4_clock *clk =
	    (struct exynos4_clock *)samsung_get_base_clock();

	/*
	 * CLK_GATE_BLOCK
	 * CLK_CAM	[0]
	 * CLK_TV	[1]
	 * CLK_MFC	[2]
	 * CLK_G3D	[3]
	 * CLK_LCD0	[4]
	 * CLK_LCD1	[5]
	 * CLK_GPS	[7]
	 */
	setbits_le32(&clk->gate_block, 1 << 4);

	/*
	 * CLK_SRC_LCD0
	 * FIMD0_SEL		[3:0]
	 * MDNIE0_SEL		[7:4]
	 * MDNIE_PWM0_SEL	[8:11]
	 * MIPI0_SEL		[12:15]
	 * set lcd0 src clock 0x6: SCLK_MPLL
	 */
	clrsetbits_le32(&clk->src_lcd0, 0xf, 0x6);

	/*
	 * CLK_GATE_IP_LCD0
	 * CLK_FIMD0		[0]
	 * CLK_MIE0		[1]
	 * CLK_MDNIE0		[2]
	 * CLK_DSIM0		[3]
	 * CLK_SMMUFIMD0	[4]
	 * CLK_PPMULCD0		[5]
	 * Gating all clocks for FIMD0
	 */
	setbits_le32(&clk->gate_ip_lcd0, 1 << 0);

	/*
	 * CLK_DIV_LCD0
	 * FIMD0_RATIO		[3:0]
	 * MDNIE0_RATIO		[7:4]
	 * MDNIE_PWM0_RATIO	[11:8]
	 * MDNIE_PWM_PRE_RATIO	[15:12]
	 * MIPI0_RATIO		[19:16]
	 * MIPI0_PRE_RATIO	[23:20]
	 * set fimd ratio
	 */
	clrsetbits_le32(&clk->div_lcd0, 0xf, 0x1);
}

void exynos5_set_lcd_clk(void)
{
	struct exynos5_clock *clk =
	    (struct exynos5_clock *)samsung_get_base_clock();

	/*
	 * CLK_GATE_BLOCK
	 * CLK_CAM	[0]
	 * CLK_TV	[1]
	 * CLK_MFC	[2]
	 * CLK_G3D	[3]
	 * CLK_LCD0	[4]
	 * CLK_LCD1	[5]
	 * CLK_GPS	[7]
	 */
	setbits_le32(&clk->gate_block, 1 << 4);

	/*
	 * CLK_SRC_LCD0
	 * FIMD0_SEL		[3:0]
	 * MDNIE0_SEL		[7:4]
	 * MDNIE_PWM0_SEL	[8:11]
	 * MIPI0_SEL		[12:15]
	 * set lcd0 src clock 0x6: SCLK_MPLL
	 */
	clrsetbits_le32(&clk->src_disp1_0, 0xf, 0x6);

	/*
	 * CLK_GATE_IP_LCD0
	 * CLK_FIMD0		[0]
	 * CLK_MIE0		[1]
	 * CLK_MDNIE0		[2]
	 * CLK_DSIM0		[3]
	 * CLK_SMMUFIMD0	[4]
	 * CLK_PPMULCD0		[5]
	 * Gating all clocks for FIMD0
	 */
	setbits_le32(&clk->gate_ip_disp1, 1 << 0);

	/*
	 * CLK_DIV_LCD0
	 * FIMD0_RATIO		[3:0]
	 * MDNIE0_RATIO		[7:4]
	 * MDNIE_PWM0_RATIO	[11:8]
	 * MDNIE_PWM_PRE_RATIO	[15:12]
	 * MIPI0_RATIO		[19:16]
	 * MIPI0_PRE_RATIO	[23:20]
	 * set fimd ratio
	 */
	clrsetbits_le32(&clk->div_disp1_0, 0xf, 0x0);
}

void exynos5420_set_lcd_clk(void)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned int cfg;

	/*
	 * CLK_SRC_DISP10
	 * FIMD1_SEL [4]
	 * 0: SCLK_RPLL
	 * 1: SCLK_SPLL
	 */
	cfg = readl(&clk->src_disp10);
	cfg &= ~(0x1 << 4);
	cfg |= (0 << 4);
	writel(cfg, &clk->src_disp10);

	/*
	 * CLK_DIV_DISP10
	 * FIMD1_RATIO		[3:0]
	 */
	cfg = readl(&clk->div_disp10);
	cfg &= ~(0xf << 0);
	cfg |= (0 << 0);
	writel(cfg, &clk->div_disp10);
}

void exynos5800_set_lcd_clk(void)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	unsigned int cfg;

	/*
	 * Use RPLL for pixel clock
	 * CLK_SRC_DISP10 CLKMUX_FIMD1 [6:4]
	 * ==================
	 * 111: SCLK_RPLL
	 */
	cfg = readl(&clk->src_disp10) | (0x7 << 4);
	writel(cfg, &clk->src_disp10);

	/*
	 * CLK_DIV_DISP10
	 * FIMD1_RATIO		[3:0]
	 */
	clrsetbits_le32(&clk->div_disp10, 0xf << 0, 0x0 << 0);
}

void exynos4_set_mipi_clk(void)
{
	struct exynos4_clock *clk =
	    (struct exynos4_clock *)samsung_get_base_clock();

	/*
	 * CLK_SRC_LCD0
	 * FIMD0_SEL		[3:0]
	 * MDNIE0_SEL		[7:4]
	 * MDNIE_PWM0_SEL	[8:11]
	 * MIPI0_SEL		[12:15]
	 * set mipi0 src clock 0x6: SCLK_MPLL
	 */
	clrsetbits_le32(&clk->src_lcd0, 0xf << 12, 0x6 << 12);

	/*
	 * CLK_SRC_MASK_LCD0
	 * FIMD0_MASK		[0]
	 * MDNIE0_MASK		[4]
	 * MDNIE_PWM0_MASK	[8]
	 * MIPI0_MASK		[12]
	 * set src mask mipi0 0x1: Unmask
	 */
	setbits_le32(&clk->src_mask_lcd0, 0x1 << 12);

	/*
	 * CLK_GATE_IP_LCD0
	 * CLK_FIMD0		[0]
	 * CLK_MIE0		[1]
	 * CLK_MDNIE0		[2]
	 * CLK_DSIM0		[3]
	 * CLK_SMMUFIMD0	[4]
	 * CLK_PPMULCD0		[5]
	 * Gating all clocks for MIPI0
	 */
	setbits_le32(&clk->gate_ip_lcd0, 1 << 3);

	/*
	 * CLK_DIV_LCD0
	 * FIMD0_RATIO		[3:0]
	 * MDNIE0_RATIO		[7:4]
	 * MDNIE_PWM0_RATIO	[11:8]
	 * MDNIE_PWM_PRE_RATIO	[15:12]
	 * MIPI0_RATIO		[19:16]
	 * MIPI0_PRE_RATIO	[23:20]
	 * set mipi ratio
	 */
	clrsetbits_le32(&clk->div_lcd0, 0xf << 16, 0x1 << 16);
}

int exynos5_set_epll_clk(unsigned long rate)
{
	unsigned int epll_con, epll_con_k;
	unsigned int i;
	unsigned int lockcnt;
	unsigned int start;
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();

	epll_con = readl(&clk->epll_con0);
	epll_con &= ~((EPLL_CON0_LOCK_DET_EN_MASK <<
			EPLL_CON0_LOCK_DET_EN_SHIFT) |
		EPLL_CON0_MDIV_MASK << EPLL_CON0_MDIV_SHIFT |
		EPLL_CON0_PDIV_MASK << EPLL_CON0_PDIV_SHIFT |
		EPLL_CON0_SDIV_MASK << EPLL_CON0_SDIV_SHIFT);

	for (i = 0; i < ARRAY_SIZE(exynos5_epll_div); i++) {
		if (exynos5_epll_div[i].freq_out == rate)
			break;
	}

	if (i == ARRAY_SIZE(exynos5_epll_div))
		return -1;

	epll_con_k = exynos5_epll_div[i].k_dsm << 0;
	epll_con |= exynos5_epll_div[i].en_lock_det <<
				EPLL_CON0_LOCK_DET_EN_SHIFT;
	epll_con |= exynos5_epll_div[i].m_div << EPLL_CON0_MDIV_SHIFT;
	epll_con |= exynos5_epll_div[i].p_div << EPLL_CON0_PDIV_SHIFT;
	epll_con |= exynos5_epll_div[i].s_div << EPLL_CON0_SDIV_SHIFT;

	/*
	 * Required period ( in cycles) to genarate a stable clock output.
	 * The maximum clock time can be up to 3000 * PDIV cycles of PLLs
	 * frequency input (as per spec)
	 */
	lockcnt = 3000 * exynos5_epll_div[i].p_div;

	writel(lockcnt, &clk->epll_lock);
	writel(epll_con, &clk->epll_con0);
	writel(epll_con_k, &clk->epll_con1);

	start = get_timer(0);

	 while (!(readl(&clk->epll_con0) &
			(0x1 << EXYNOS5_EPLLCON0_LOCKED_SHIFT))) {
		if (get_timer(start) > TIMEOUT_EPLL_LOCK) {
			debug("%s: Timeout waiting for EPLL lock\n", __func__);
			return -1;
		}
	}
	return 0;
}

int exynos5_set_i2s_clk_source(unsigned int i2s_id)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned int *audio_ass = (unsigned int *)samsung_get_base_audio_ass();

	if (i2s_id == 0) {
		setbits_le32(&clk->src_top2, CLK_SRC_MOUT_EPLL);
		clrsetbits_le32(&clk->src_mau, AUDIO0_SEL_MASK,
				(CLK_SRC_SCLK_EPLL));
		setbits_le32(audio_ass, AUDIO_CLKMUX_ASS);
	} else if (i2s_id == 1) {
		clrsetbits_le32(&clk->src_peric1, AUDIO1_SEL_MASK,
				(CLK_SRC_SCLK_EPLL));
	} else {
		return -1;
	}
	return 0;
}

int exynos5_set_i2s_clk_prescaler(unsigned int src_frq,
				  unsigned int dst_frq,
				  unsigned int i2s_id)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	unsigned int div;

	if ((dst_frq == 0) || (src_frq == 0)) {
		debug("%s: Invalid requency input for prescaler\n", __func__);
		debug("src frq = %d des frq = %d ", src_frq, dst_frq);
		return -1;
	}

	div = (src_frq / dst_frq);
	if (i2s_id == 0) {
		if (div > AUDIO_0_RATIO_MASK) {
			debug("%s: Frequency ratio is out of range\n",
			      __func__);
			debug("src frq = %d des frq = %d ", src_frq, dst_frq);
			return -1;
		}
		clrsetbits_le32(&clk->div_mau, AUDIO_0_RATIO_MASK,
				(div & AUDIO_0_RATIO_MASK));
	} else if (i2s_id == 1) {
		if (div > AUDIO_1_RATIO_MASK) {
			debug("%s: Frequency ratio is out of range\n",
			      __func__);
			debug("src frq = %d des frq = %d ", src_frq, dst_frq);
			return -1;
		}
		clrsetbits_le32(&clk->div_peric4, AUDIO_1_RATIO_MASK,
				(div & AUDIO_1_RATIO_MASK));
	} else {
		return -1;
	}
	return 0;
}

/**
 * Linearly searches for the most accurate main and fine stage clock scalars
 * (divisors) for a specified target frequency and scalar bit sizes by checking
 * all multiples of main_scalar_bits values. Will always return scalars up to or
 * slower than target.
 *
 * @param main_scalar_bits	Number of main scalar bits, must be > 0 and < 32
 * @param fine_scalar_bits	Number of fine scalar bits, must be > 0 and < 32
 * @param input_freq		Clock frequency to be scaled in Hz
 * @param target_freq		Desired clock frequency in Hz
 * @param best_fine_scalar	Pointer to store the fine stage divisor
 *
 * @return best_main_scalar	Main scalar for desired frequency or -1 if none
 * found
 */
static int clock_calc_best_scalar(unsigned int main_scaler_bits,
	unsigned int fine_scalar_bits, unsigned int input_rate,
	unsigned int target_rate, unsigned int *best_fine_scalar)
{
	int i;
	int best_main_scalar = -1;
	unsigned int best_error = target_rate;
	const unsigned int cap = (1 << fine_scalar_bits) - 1;
	const unsigned int loops = 1 << main_scaler_bits;

	debug("Input Rate is %u, Target is %u, Cap is %u\n", input_rate,
			target_rate, cap);

	assert(best_fine_scalar != NULL);
	assert(main_scaler_bits <= fine_scalar_bits);

	*best_fine_scalar = 1;

	if (input_rate == 0 || target_rate == 0)
		return -1;

	if (target_rate >= input_rate)
		return 1;

	for (i = 1; i <= loops; i++) {
		const unsigned int effective_div =
			max(min(input_rate / i / target_rate, cap), 1U);
		const unsigned int effective_rate = input_rate / i /
							effective_div;
		const int error = target_rate - effective_rate;

		debug("%d|effdiv:%u, effrate:%u, error:%d\n", i, effective_div,
				effective_rate, error);

		if (error >= 0 && error <= best_error) {
			best_error = error;
			best_main_scalar = i;
			*best_fine_scalar = effective_div;
		}
	}

	return best_main_scalar;
}

static int exynos5_set_spi_clk(enum periph_id periph_id,
					unsigned int rate)
{
	struct exynos5_clock *clk =
		(struct exynos5_clock *)samsung_get_base_clock();
	int main;
	unsigned int fine;
	unsigned shift, pre_shift;
	unsigned mask = 0xff;
	u32 *reg;

	main = clock_calc_best_scalar(4, 8, 400000000, rate, &fine);
	if (main < 0) {
		debug("%s: Cannot set clock rate for periph %d",
				__func__, periph_id);
		return -1;
	}
	main = main - 1;
	fine = fine - 1;

	switch (periph_id) {
	case PERIPH_ID_SPI0:
		reg = &clk->div_peric1;
		shift = 0;
		pre_shift = 8;
		break;
	case PERIPH_ID_SPI1:
		reg = &clk->div_peric1;
		shift = 16;
		pre_shift = 24;
		break;
	case PERIPH_ID_SPI2:
		reg = &clk->div_peric2;
		shift = 0;
		pre_shift = 8;
		break;
	case PERIPH_ID_SPI3:
		reg = &clk->sclk_div_isp;
		shift = 0;
		pre_shift = 4;
		break;
	case PERIPH_ID_SPI4:
		reg = &clk->sclk_div_isp;
		shift = 12;
		pre_shift = 16;
		break;
	default:
		debug("%s: Unsupported peripheral ID %d\n", __func__,
		      periph_id);
		return -1;
	}
	clrsetbits_le32(reg, mask << shift, (main & mask) << shift);
	clrsetbits_le32(reg, mask << pre_shift, (fine & mask) << pre_shift);

	return 0;
}

static int exynos5420_set_spi_clk(enum periph_id periph_id,
					unsigned int rate)
{
	struct exynos5420_clock *clk =
		(struct exynos5420_clock *)samsung_get_base_clock();
	int main;
	unsigned int fine;
	unsigned shift, pre_shift;
	unsigned div_mask = 0xf, pre_div_mask = 0xff;
	u32 *reg;
	u32 *pre_reg;

	main = clock_calc_best_scalar(4, 8, 400000000, rate, &fine);
	if (main < 0) {
		debug("%s: Cannot set clock rate for periph %d",
		      __func__, periph_id);
		return -1;
	}
	main = main - 1;
	fine = fine - 1;

	switch (periph_id) {
	case PERIPH_ID_SPI0:
		reg = &clk->div_peric1;
		shift = 20;
		pre_reg = &clk->div_peric4;
		pre_shift = 8;
		break;
	case PERIPH_ID_SPI1:
		reg = &clk->div_peric1;
		shift = 24;
		pre_reg = &clk->div_peric4;
		pre_shift = 16;
		break;
	case PERIPH_ID_SPI2:
		reg = &clk->div_peric1;
		shift = 28;
		pre_reg = &clk->div_peric4;
		pre_shift = 24;
		break;
	case PERIPH_ID_SPI3:
		reg = &clk->div_isp1;
		shift = 16;
		pre_reg = &clk->div_isp1;
		pre_shift = 0;
		break;
	case PERIPH_ID_SPI4:
		reg = &clk->div_isp1;
		shift = 20;
		pre_reg = &clk->div_isp1;
		pre_shift = 8;
		break;
	default:
		debug("%s: Unsupported peripheral ID %d\n", __func__,
		      periph_id);
		return -1;
	}

	clrsetbits_le32(reg, div_mask << shift, (main & div_mask) << shift);
	clrsetbits_le32(pre_reg, pre_div_mask << pre_shift,
			(fine & pre_div_mask) << pre_shift);

	return 0;
}

static unsigned long exynos4_get_i2c_clk(void)
{
	struct exynos4_clock *clk =
		(struct exynos4_clock *)samsung_get_base_clock();
	unsigned long sclk, aclk_100;
	unsigned int ratio;

	sclk = get_pll_clk(APLL);

	ratio = (readl(&clk->div_top)) >> 4;
	ratio &= 0xf;
	aclk_100 = sclk / (ratio + 1);
	return aclk_100;
}

unsigned long get_pll_clk(int pllreg)
{
	if (cpu_is_exynos5()) {
		if (proid_is_exynos5420() || proid_is_exynos5422())
			return exynos542x_get_pll_clk(pllreg);
		return exynos5_get_pll_clk(pllreg);
	} else if (cpu_is_exynos4()) {
		if (proid_is_exynos4412())
			return exynos4x12_get_pll_clk(pllreg);
		return exynos4_get_pll_clk(pllreg);
	}

	return 0;
}

unsigned long get_arm_clk(void)
{
	if (cpu_is_exynos5()) {
		return exynos5_get_arm_clk();
	} else if (cpu_is_exynos4()) {
		if (proid_is_exynos4412())
			return exynos4x12_get_arm_clk();
		return exynos4_get_arm_clk();
	}

	return 0;
}

unsigned long get_i2c_clk(void)
{
	if (cpu_is_exynos5())
		return clock_get_periph_rate(PERIPH_ID_I2C0);
	else if (cpu_is_exynos4())
		return exynos4_get_i2c_clk();

	return 0;
}

unsigned long get_pwm_clk(void)
{
	if (cpu_is_exynos5()) {
		return clock_get_periph_rate(PERIPH_ID_PWM0);
	} else if (cpu_is_exynos4()) {
		if (proid_is_exynos4412())
			return exynos4x12_get_pwm_clk();
		return exynos4_get_pwm_clk();
	}

	return 0;
}

unsigned long get_uart_clk(int dev_index)
{
	enum periph_id id;

	switch (dev_index) {
	case 0:
		id = PERIPH_ID_UART0;
		break;
	case 1:
		id = PERIPH_ID_UART1;
		break;
	case 2:
		id = PERIPH_ID_UART2;
		break;
	case 3:
		id = PERIPH_ID_UART3;
		break;
	default:
		debug("%s: invalid UART index %d", __func__, dev_index);
		return -1;
	}

	if (cpu_is_exynos5()) {
		return clock_get_periph_rate(id);
	} else if (cpu_is_exynos4()) {
		if (proid_is_exynos4412())
			return exynos4x12_get_uart_clk(dev_index);
		return exynos4_get_uart_clk(dev_index);
	}

	return 0;
}

unsigned long get_mmc_clk(int dev_index)
{
	enum periph_id id;

	if (cpu_is_exynos4())
		return exynos4_get_mmc_clk(dev_index);

	switch (dev_index) {
	case 0:
		id = PERIPH_ID_SDMMC0;
		break;
	case 1:
		id = PERIPH_ID_SDMMC1;
		break;
	case 2:
		id = PERIPH_ID_SDMMC2;
		break;
	case 3:
		id = PERIPH_ID_SDMMC3;
		break;
	default:
		debug("%s: invalid MMC index %d", __func__, dev_index);
		return -1;
	}

	return clock_get_periph_rate(id);
}

void set_mmc_clk(int dev_index, unsigned int div)
{
	/* If want to set correct value, it needs to substract one from div.*/
	if (div > 0)
		div -= 1;

	if (cpu_is_exynos5()) {
		if (proid_is_exynos5420() || proid_is_exynos5422())
			exynos5420_set_mmc_clk(dev_index, div);
		else
			exynos5_set_mmc_clk(dev_index, div);
	} else if (cpu_is_exynos4()) {
		exynos4_set_mmc_clk(dev_index, div);
	}
}

unsigned long get_lcd_clk(void)
{
	if (cpu_is_exynos4()) {
		return exynos4_get_lcd_clk();
	} else if (cpu_is_exynos5()) {
		if (proid_is_exynos5420())
			return exynos5420_get_lcd_clk();
		else if (proid_is_exynos5422())
			return exynos5800_get_lcd_clk();
		else
			return exynos5_get_lcd_clk();
	}

	return 0;
}

void set_lcd_clk(void)
{
	if (cpu_is_exynos4()) {
		exynos4_set_lcd_clk();
	} else if (cpu_is_exynos5()) {
		if (proid_is_exynos5250())
			exynos5_set_lcd_clk();
		else if (proid_is_exynos5420())
			exynos5420_set_lcd_clk();
		else
			exynos5800_set_lcd_clk();
	}
}

void set_mipi_clk(void)
{
	if (cpu_is_exynos4())
		exynos4_set_mipi_clk();
}

int set_spi_clk(int periph_id, unsigned int rate)
{
	if (cpu_is_exynos5()) {
		if (proid_is_exynos5420() || proid_is_exynos5422())
			return exynos5420_set_spi_clk(periph_id, rate);
		return exynos5_set_spi_clk(periph_id, rate);
	}

	return 0;
}

int set_i2s_clk_prescaler(unsigned int src_frq, unsigned int dst_frq,
			  unsigned int i2s_id)
{
	if (cpu_is_exynos5())
		return exynos5_set_i2s_clk_prescaler(src_frq, dst_frq, i2s_id);

	return 0;
}

int set_i2s_clk_source(unsigned int i2s_id)
{
	if (cpu_is_exynos5())
		return exynos5_set_i2s_clk_source(i2s_id);

	return 0;
}

int set_epll_clk(unsigned long rate)
{
	if (cpu_is_exynos5())
		return exynos5_set_epll_clk(rate);

	return 0;
}