arch/mips/ar7/clock.c - arm/linux - Git at Google

 /*
  * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
  * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
  * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
  *
  * 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, or
  * (at your option) any later version.
  *
  * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/export.h>
 #include <linux/delay.h>
 #include <linux/gcd.h>
 #include <linux/io.h>
 #include <linux/err.h>
 #include <linux/clk.h>

 #include <asm/addrspace.h>
 #include <asm/mach-ar7/ar7.h>

 #define BOOT_PLL_SOURCE_MASK	0x3
 #define CPU_PLL_SOURCE_SHIFT	16
 #define BUS_PLL_SOURCE_SHIFT	14
 #define USB_PLL_SOURCE_SHIFT	18
 #define DSP_PLL_SOURCE_SHIFT	22
 #define BOOT_PLL_SOURCE_AFE	0
 #define BOOT_PLL_SOURCE_BUS	0
 #define BOOT_PLL_SOURCE_REF	1
 #define BOOT_PLL_SOURCE_XTAL	2
 #define BOOT_PLL_SOURCE_CPU	3
 #define BOOT_PLL_BYPASS		0x00000020
 #define BOOT_PLL_ASYNC_MODE	0x02000000
 #define BOOT_PLL_2TO1_MODE	0x00008000

 #define TNETD7200_CLOCK_ID_CPU	0
 #define TNETD7200_CLOCK_ID_DSP	1
 #define TNETD7200_CLOCK_ID_USB	2

 #define TNETD7200_DEF_CPU_CLK	211000000
 #define TNETD7200_DEF_DSP_CLK	125000000
 #define TNETD7200_DEF_USB_CLK	48000000

 struct tnetd7300_clock {
 	u32 ctrl;
 #define PREDIV_MASK	0x001f0000
 #define PREDIV_SHIFT	16
 #define POSTDIV_MASK	0x0000001f
 	u32 unused1[3];
 	u32 pll;
 #define MUL_MASK	0x0000f000
 #define MUL_SHIFT	12
 #define PLL_MODE_MASK	0x00000001
 #define PLL_NDIV	0x00000800
 #define PLL_DIV		0x00000002
 #define PLL_STATUS	0x00000001
 	u32 unused2[3];
 };

 struct tnetd7300_clocks {
 	struct tnetd7300_clock bus;
 	struct tnetd7300_clock cpu;
 	struct tnetd7300_clock usb;
 	struct tnetd7300_clock dsp;
 };

 struct tnetd7200_clock {
 	u32 ctrl;
 	u32 unused1[3];
 #define DIVISOR_ENABLE_MASK 0x00008000
 	u32 mul;
 	u32 prediv;
 	u32 postdiv;
 	u32 postdiv2;
 	u32 unused2[6];
 	u32 cmd;
 	u32 status;
 	u32 cmden;
 	u32 padding[15];
 };

 struct tnetd7200_clocks {
 	struct tnetd7200_clock cpu;
 	struct tnetd7200_clock dsp;
 	struct tnetd7200_clock usb;
 };

 static struct clk bus_clk = {
 	.rate	= 125000000,
 };

 static struct clk cpu_clk = {
 	.rate	= 150000000,
 };

 static struct clk dsp_clk;
 static struct clk vbus_clk;

 static void approximate(int base, int target, int *prediv,
 			int *postdiv, int *mul)
 {
 	int i, j, k, freq, res = target;
 	for (i = 1; i <= 16; i++)
 		for (j = 1; j <= 32; j++)
 			for (k = 1; k <= 32; k++) {
 				freq = abs(base / j * i / k - target);
 				if (freq < res) {
 					res = freq;
 					*mul = i;
 					*prediv = j;
 					*postdiv = k;
 				}
 			}
 }

 static void calculate(int base, int target, int *prediv, int *postdiv,
 	int *mul)
 {
 	int tmp_gcd, tmp_base, tmp_freq;

 	for (*prediv = 1; *prediv <= 32; (*prediv)++) {
 		tmp_base = base / *prediv;
 		tmp_gcd = gcd(target, tmp_base);
 		*mul = target / tmp_gcd;
 		*postdiv = tmp_base / tmp_gcd;
 		if ((*mul < 1) || (*mul >= 16))
 			continue;
 		if ((*postdiv > 0) & (*postdiv <= 32))
 			break;
 	}

 	if (base / *prediv * *mul / *postdiv != target) {
 		approximate(base, target, prediv, postdiv, mul);
 		tmp_freq = base / *prediv * *mul / *postdiv;
 		printk(KERN_WARNING
 		       "Adjusted requested frequency %d to %d\n",
 		       target, tmp_freq);
 	}

 	printk(KERN_DEBUG "Clocks: prediv: %d, postdiv: %d, mul: %d\n",
 	       *prediv, *postdiv, *mul);
 }

 static int tnetd7300_dsp_clock(void)
 {
 	u32 didr1, didr2;
 	u8 rev = ar7_chip_rev();
 	didr1 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x18));
 	didr2 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x1c));
 	if (didr2 & (1 << 23))
 		return 0;
 	if ((rev >= 0x23) && (rev != 0x57))
 		return 250000000;
 	if ((((didr2 & 0x1fff) << 10) | ((didr1 & 0xffc00000) >> 22))
 	    > 4208000)
 		return 250000000;
 	return 0;
 }

 static int tnetd7300_get_clock(u32 shift, struct tnetd7300_clock *clock,
 	u32 *bootcr, u32 bus_clock)
 {
 	int product;
 	int base_clock = AR7_REF_CLOCK;
 	u32 ctrl = readl(&clock->ctrl);
 	u32 pll = readl(&clock->pll);
 	int prediv = ((ctrl & PREDIV_MASK) >> PREDIV_SHIFT) + 1;
 	int postdiv = (ctrl & POSTDIV_MASK) + 1;
 	int divisor = prediv * postdiv;
 	int mul = ((pll & MUL_MASK) >> MUL_SHIFT) + 1;

 	switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
 	case BOOT_PLL_SOURCE_BUS:
 		base_clock = bus_clock;
 		break;
 	case BOOT_PLL_SOURCE_REF:
 		base_clock = AR7_REF_CLOCK;
 		break;
 	case BOOT_PLL_SOURCE_XTAL:
 		base_clock = AR7_XTAL_CLOCK;
 		break;
 	case BOOT_PLL_SOURCE_CPU:
 		base_clock = cpu_clk.rate;
 		break;
 	}

 	if (*bootcr & BOOT_PLL_BYPASS)
 		return base_clock / divisor;

 	if ((pll & PLL_MODE_MASK) == 0)
 		return (base_clock >> (mul / 16 + 1)) / divisor;

 	if ((pll & (PLL_NDIV | PLL_DIV)) == (PLL_NDIV | PLL_DIV)) {
 		product = (mul & 1) ?
 			(base_clock * mul) >> 1 :
 			(base_clock * (mul - 1)) >> 2;
 		return product / divisor;
 	}

 	if (mul == 16)
 		return base_clock / divisor;

 	return base_clock * mul / divisor;
 }

 static void tnetd7300_set_clock(u32 shift, struct tnetd7300_clock *clock,
 	u32 *bootcr, u32 frequency)
 {
 	int prediv, postdiv, mul;
 	int base_clock = bus_clk.rate;

 	switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
 	case BOOT_PLL_SOURCE_BUS:
 		base_clock = bus_clk.rate;
 		break;
 	case BOOT_PLL_SOURCE_REF:
 		base_clock = AR7_REF_CLOCK;
 		break;
 	case BOOT_PLL_SOURCE_XTAL:
 		base_clock = AR7_XTAL_CLOCK;
 		break;
 	case BOOT_PLL_SOURCE_CPU:
 		base_clock = cpu_clk.rate;
 		break;
 	}

 	calculate(base_clock, frequency, &prediv, &postdiv, &mul);

 	writel(((prediv - 1) << PREDIV_SHIFT) | (postdiv - 1), &clock->ctrl);
 	mdelay(1);
 	writel(4, &clock->pll);
 	while (readl(&clock->pll) & PLL_STATUS)
 		;
 	writel(((mul - 1) << MUL_SHIFT) | (0xff << 3) | 0x0e, &clock->pll);
 	mdelay(75);
 }

 static void __init tnetd7300_init_clocks(void)
 {
 	u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
 	struct tnetd7300_clocks *clocks =
 					ioremap_nocache(UR8_REGS_CLOCKS,
 					sizeof(struct tnetd7300_clocks));

 	bus_clk.rate = tnetd7300_get_clock(BUS_PLL_SOURCE_SHIFT,
 		&clocks->bus, bootcr, AR7_AFE_CLOCK);

 	if (*bootcr & BOOT_PLL_ASYNC_MODE)
 		cpu_clk.rate = tnetd7300_get_clock(CPU_PLL_SOURCE_SHIFT,
 			&clocks->cpu, bootcr, AR7_AFE_CLOCK);
 	else
 		cpu_clk.rate = bus_clk.rate;

 	if (dsp_clk.rate == 250000000)
 		tnetd7300_set_clock(DSP_PLL_SOURCE_SHIFT, &clocks->dsp,
 			bootcr, dsp_clk.rate);

 	iounmap(clocks);
 	iounmap(bootcr);
 }

 static void tnetd7200_set_clock(int base, struct tnetd7200_clock *clock,
 	int prediv, int postdiv, int postdiv2, int mul, u32 frequency)
 {
 	printk(KERN_INFO
 		"Clocks: base = %d, frequency = %u, prediv = %d, "
 		"postdiv = %d, postdiv2 = %d, mul = %d\n",
 		base, frequency, prediv, postdiv, postdiv2, mul);

 	writel(0, &clock->ctrl);
 	writel(DIVISOR_ENABLE_MASK | ((prediv - 1) & 0x1F), &clock->prediv);
 	writel((mul - 1) & 0xF, &clock->mul);

 	while (readl(&clock->status) & 0x1)
 		; /* nop */

 	writel(DIVISOR_ENABLE_MASK | ((postdiv - 1) & 0x1F), &clock->postdiv);

 	writel(readl(&clock->cmden) | 1, &clock->cmden);
 	writel(readl(&clock->cmd) | 1, &clock->cmd);

 	while (readl(&clock->status) & 0x1)
 		; /* nop */

 	writel(DIVISOR_ENABLE_MASK | ((postdiv2 - 1) & 0x1F), &clock->postdiv2);

 	writel(readl(&clock->cmden) | 1, &clock->cmden);
 	writel(readl(&clock->cmd) | 1, &clock->cmd);

 	while (readl(&clock->status) & 0x1)
 		; /* nop */

 	writel(readl(&clock->ctrl) | 1, &clock->ctrl);
 }

 static int tnetd7200_get_clock_base(int clock_id, u32 *bootcr)
 {
 	if (*bootcr & BOOT_PLL_ASYNC_MODE)
 		/* Async */
 		switch (clock_id) {
 		case TNETD7200_CLOCK_ID_DSP:
 			return AR7_REF_CLOCK;
 		default:
 			return AR7_AFE_CLOCK;
 		}
 	else
 		/* Sync */
 		if (*bootcr & BOOT_PLL_2TO1_MODE)
 			/* 2:1 */
 			switch (clock_id) {
 			case TNETD7200_CLOCK_ID_DSP:
 				return AR7_REF_CLOCK;
 			default:
 				return AR7_AFE_CLOCK;
 			}
 		else
 			/* 1:1 */
 			return AR7_REF_CLOCK;
 }


 static void __init tnetd7200_init_clocks(void)
 {
 	u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
 	struct tnetd7200_clocks *clocks =
 					ioremap_nocache(AR7_REGS_CLOCKS,
 					sizeof(struct tnetd7200_clocks));
 	int cpu_base, cpu_mul, cpu_prediv, cpu_postdiv;
 	int dsp_base, dsp_mul, dsp_prediv, dsp_postdiv;
 	int usb_base, usb_mul, usb_prediv, usb_postdiv;

 	cpu_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_CPU, bootcr);
 	dsp_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_DSP, bootcr);

 	if (*bootcr & BOOT_PLL_ASYNC_MODE) {
 		printk(KERN_INFO "Clocks: Async mode\n");

 		printk(KERN_INFO "Clocks: Setting DSP clock\n");
 		calculate(dsp_base, TNETD7200_DEF_DSP_CLK,
 			&dsp_prediv, &dsp_postdiv, &dsp_mul);
 		bus_clk.rate =
 			((dsp_base / dsp_prediv) * dsp_mul) / dsp_postdiv;
 		tnetd7200_set_clock(dsp_base, &clocks->dsp,
 			dsp_prediv, dsp_postdiv * 2, dsp_postdiv, dsp_mul * 2,
 			bus_clk.rate);

 		printk(KERN_INFO "Clocks: Setting CPU clock\n");
 		calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
 			&cpu_postdiv, &cpu_mul);
 		cpu_clk.rate =
 			((cpu_base / cpu_prediv) * cpu_mul) / cpu_postdiv;
 		tnetd7200_set_clock(cpu_base, &clocks->cpu,
 			cpu_prediv, cpu_postdiv, -1, cpu_mul,
 			cpu_clk.rate);

 	} else
 		if (*bootcr & BOOT_PLL_2TO1_MODE) {
 			printk(KERN_INFO "Clocks: Sync 2:1 mode\n");

 			printk(KERN_INFO "Clocks: Setting CPU clock\n");
 			calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
 				&cpu_postdiv, &cpu_mul);
 			cpu_clk.rate = ((cpu_base / cpu_prediv) * cpu_mul)
 								/ cpu_postdiv;
 			tnetd7200_set_clock(cpu_base, &clocks->cpu,
 				cpu_prediv, cpu_postdiv, -1, cpu_mul,
 				cpu_clk.rate);

 			printk(KERN_INFO "Clocks: Setting DSP clock\n");
 			calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
 				&dsp_postdiv, &dsp_mul);
 			bus_clk.rate = cpu_clk.rate / 2;
 			tnetd7200_set_clock(dsp_base, &clocks->dsp,
 				dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
 				dsp_mul * 2, bus_clk.rate);
 		} else {
 			printk(KERN_INFO "Clocks: Sync 1:1 mode\n");

 			printk(KERN_INFO "Clocks: Setting DSP clock\n");
 			calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
 				&dsp_postdiv, &dsp_mul);
 			bus_clk.rate = ((dsp_base / dsp_prediv) * dsp_mul)
 								/ dsp_postdiv;
 			tnetd7200_set_clock(dsp_base, &clocks->dsp,
 				dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
 				dsp_mul * 2, bus_clk.rate);

 			cpu_clk.rate = bus_clk.rate;
 		}

 	printk(KERN_INFO "Clocks: Setting USB clock\n");
 	usb_base = bus_clk.rate;
 	calculate(usb_base, TNETD7200_DEF_USB_CLK, &usb_prediv,
 		&usb_postdiv, &usb_mul);
 	tnetd7200_set_clock(usb_base, &clocks->usb,
 		usb_prediv, usb_postdiv, -1, usb_mul,
 		TNETD7200_DEF_USB_CLK);

 	dsp_clk.rate = cpu_clk.rate;

 	iounmap(clocks);
 	iounmap(bootcr);
 }

 /*
  * Linux clock API
  */
 int clk_enable(struct clk *clk)
 {
 	return 0;
 }
 EXPORT_SYMBOL(clk_enable);

 void clk_disable(struct clk *clk)
 {
 }
 EXPORT_SYMBOL(clk_disable);

 unsigned long clk_get_rate(struct clk *clk)
 {
 	if (!clk)
 		return 0;

 	return clk->rate;
 }
 EXPORT_SYMBOL(clk_get_rate);

 struct clk *clk_get(struct device *dev, const char *id)
 {
 	if (!strcmp(id, "bus"))
 		return &bus_clk;
 	/* cpmac and vbus share the same rate */
 	if (!strcmp(id, "cpmac"))
 		return &vbus_clk;
 	if (!strcmp(id, "cpu"))
 		return &cpu_clk;
 	if (!strcmp(id, "dsp"))
 		return &dsp_clk;
 	if (!strcmp(id, "vbus"))
 		return &vbus_clk;
 	return ERR_PTR(-ENOENT);
 }
 EXPORT_SYMBOL(clk_get);

 void clk_put(struct clk *clk)
 {
 }
 EXPORT_SYMBOL(clk_put);

 void __init ar7_init_clocks(void)
 {
 	switch (ar7_chip_id()) {
 	case AR7_CHIP_7100:
 	case AR7_CHIP_7200:
 		tnetd7200_init_clocks();
 		break;
 	case AR7_CHIP_7300:
 		dsp_clk.rate = tnetd7300_dsp_clock();
 		tnetd7300_init_clocks();
 		break;
 	default:
 		break;
 	}
 	/* adjust vbus clock rate */
 	vbus_clk.rate = bus_clk.rate / 2;
 }
	/*
	* Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
	* Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
	* Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
	*
	* 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, or
	* (at your option) any later version.
	*
	* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/types.h>
	#include <linux/export.h>
	#include <linux/delay.h>
	#include <linux/gcd.h>
	#include <linux/io.h>
	#include <linux/err.h>
	#include <linux/clk.h>

	#include <asm/addrspace.h>
	#include <asm/mach-ar7/ar7.h>

	#define BOOT_PLL_SOURCE_MASK 0x3
	#define CPU_PLL_SOURCE_SHIFT 16
	#define BUS_PLL_SOURCE_SHIFT 14
	#define USB_PLL_SOURCE_SHIFT 18
	#define DSP_PLL_SOURCE_SHIFT 22
	#define BOOT_PLL_SOURCE_AFE 0
	#define BOOT_PLL_SOURCE_BUS 0
	#define BOOT_PLL_SOURCE_REF 1
	#define BOOT_PLL_SOURCE_XTAL 2
	#define BOOT_PLL_SOURCE_CPU 3
	#define BOOT_PLL_BYPASS 0x00000020
	#define BOOT_PLL_ASYNC_MODE 0x02000000
	#define BOOT_PLL_2TO1_MODE 0x00008000

	#define TNETD7200_CLOCK_ID_CPU 0
	#define TNETD7200_CLOCK_ID_DSP 1
	#define TNETD7200_CLOCK_ID_USB 2

	#define TNETD7200_DEF_CPU_CLK 211000000
	#define TNETD7200_DEF_DSP_CLK 125000000
	#define TNETD7200_DEF_USB_CLK 48000000

	struct tnetd7300_clock {
	u32 ctrl;
	#define PREDIV_MASK 0x001f0000
	#define PREDIV_SHIFT 16
	#define POSTDIV_MASK 0x0000001f
	u32 unused1[3];
	u32 pll;
	#define MUL_MASK 0x0000f000
	#define MUL_SHIFT 12
	#define PLL_MODE_MASK 0x00000001
	#define PLL_NDIV 0x00000800
	#define PLL_DIV 0x00000002
	#define PLL_STATUS 0x00000001
	u32 unused2[3];
	};

	struct tnetd7300_clocks {
	struct tnetd7300_clock bus;
	struct tnetd7300_clock cpu;
	struct tnetd7300_clock usb;
	struct tnetd7300_clock dsp;
	};

	struct tnetd7200_clock {
	u32 ctrl;
	u32 unused1[3];
	#define DIVISOR_ENABLE_MASK 0x00008000
	u32 mul;
	u32 prediv;
	u32 postdiv;
	u32 postdiv2;
	u32 unused2[6];
	u32 cmd;
	u32 status;
	u32 cmden;
	u32 padding[15];
	};

	struct tnetd7200_clocks {
	struct tnetd7200_clock cpu;
	struct tnetd7200_clock dsp;
	struct tnetd7200_clock usb;
	};

	static struct clk bus_clk = {
	.rate = 125000000,
	};

	static struct clk cpu_clk = {
	.rate = 150000000,
	};

	static struct clk dsp_clk;
	static struct clk vbus_clk;

	static void approximate(int base, int target, int *prediv,
	int postdiv, int mul)
	{
	int i, j, k, freq, res = target;
	for (i = 1; i <= 16; i++)
	for (j = 1; j <= 32; j++)
	for (k = 1; k <= 32; k++) {
	freq = abs(base / j * i / k - target);
	if (freq < res) {
	res = freq;
	*mul = i;
	*prediv = j;
	*postdiv = k;
	}
	}
	}

	static void calculate(int base, int target, int prediv, int postdiv,
	int *mul)
	{
	int tmp_gcd, tmp_base, tmp_freq;

	for (prediv = 1; prediv <= 32; (*prediv)++) {
	tmp_base = base / *prediv;
	tmp_gcd = gcd(target, tmp_base);
	*mul = target / tmp_gcd;
	*postdiv = tmp_base / tmp_gcd;
	if ((mul < 1) \|\| (mul >= 16))
	continue;
	if ((postdiv > 0) & (postdiv <= 32))
	break;
	}

	if (base / prediv mul / postdiv != target) {
	approximate(base, target, prediv, postdiv, mul);
	tmp_freq = base / prediv mul / postdiv;
	printk(KERN_WARNING
	"Adjusted requested frequency %d to %d\n",
	target, tmp_freq);
	}

	printk(KERN_DEBUG "Clocks: prediv: %d, postdiv: %d, mul: %d\n",
	prediv, postdiv, *mul);
	}

	static int tnetd7300_dsp_clock(void)
	{
	u32 didr1, didr2;
	u8 rev = ar7_chip_rev();
	didr1 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x18));
	didr2 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x1c));
	if (didr2 & (1 << 23))
	return 0;
	if ((rev >= 0x23) && (rev != 0x57))
	return 250000000;
	if ((((didr2 & 0x1fff) << 10) \| ((didr1 & 0xffc00000) >> 22))
	> 4208000)
	return 250000000;
	return 0;
	}

	static int tnetd7300_get_clock(u32 shift, struct tnetd7300_clock *clock,
	u32 *bootcr, u32 bus_clock)
	{
	int product;
	int base_clock = AR7_REF_CLOCK;
	u32 ctrl = readl(&clock->ctrl);
	u32 pll = readl(&clock->pll);
	int prediv = ((ctrl & PREDIV_MASK) >> PREDIV_SHIFT) + 1;
	int postdiv = (ctrl & POSTDIV_MASK) + 1;
	int divisor = prediv * postdiv;
	int mul = ((pll & MUL_MASK) >> MUL_SHIFT) + 1;

	switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
	case BOOT_PLL_SOURCE_BUS:
	base_clock = bus_clock;
	break;
	case BOOT_PLL_SOURCE_REF:
	base_clock = AR7_REF_CLOCK;
	break;
	case BOOT_PLL_SOURCE_XTAL:
	base_clock = AR7_XTAL_CLOCK;
	break;
	case BOOT_PLL_SOURCE_CPU:
	base_clock = cpu_clk.rate;
	break;
	}

	if (*bootcr & BOOT_PLL_BYPASS)
	return base_clock / divisor;

	if ((pll & PLL_MODE_MASK) == 0)
	return (base_clock >> (mul / 16 + 1)) / divisor;

	if ((pll & (PLL_NDIV \| PLL_DIV)) == (PLL_NDIV \| PLL_DIV)) {
	product = (mul & 1) ?
	(base_clock * mul) >> 1 :
	(base_clock * (mul - 1)) >> 2;
	return product / divisor;
	}

	if (mul == 16)
	return base_clock / divisor;

	return base_clock * mul / divisor;
	}

	static void tnetd7300_set_clock(u32 shift, struct tnetd7300_clock *clock,
	u32 *bootcr, u32 frequency)
	{
	int prediv, postdiv, mul;
	int base_clock = bus_clk.rate;

	switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) {
	case BOOT_PLL_SOURCE_BUS:
	base_clock = bus_clk.rate;
	break;
	case BOOT_PLL_SOURCE_REF:
	base_clock = AR7_REF_CLOCK;
	break;
	case BOOT_PLL_SOURCE_XTAL:
	base_clock = AR7_XTAL_CLOCK;
	break;
	case BOOT_PLL_SOURCE_CPU:
	base_clock = cpu_clk.rate;
	break;
	}

	calculate(base_clock, frequency, &prediv, &postdiv, &mul);

	writel(((prediv - 1) << PREDIV_SHIFT) \| (postdiv - 1), &clock->ctrl);
	mdelay(1);
	writel(4, &clock->pll);
	while (readl(&clock->pll) & PLL_STATUS)
	;
	writel(((mul - 1) << MUL_SHIFT) \| (0xff << 3) \| 0x0e, &clock->pll);
	mdelay(75);
	}

	static void __init tnetd7300_init_clocks(void)
	{
	u32 bootcr = (u32 )ioremap_nocache(AR7_REGS_DCL, 4);
	struct tnetd7300_clocks *clocks =
	ioremap_nocache(UR8_REGS_CLOCKS,
	sizeof(struct tnetd7300_clocks));

	bus_clk.rate = tnetd7300_get_clock(BUS_PLL_SOURCE_SHIFT,
	&clocks->bus, bootcr, AR7_AFE_CLOCK);

	if (*bootcr & BOOT_PLL_ASYNC_MODE)
	cpu_clk.rate = tnetd7300_get_clock(CPU_PLL_SOURCE_SHIFT,
	&clocks->cpu, bootcr, AR7_AFE_CLOCK);
	else
	cpu_clk.rate = bus_clk.rate;

	if (dsp_clk.rate == 250000000)
	tnetd7300_set_clock(DSP_PLL_SOURCE_SHIFT, &clocks->dsp,
	bootcr, dsp_clk.rate);

	iounmap(clocks);
	iounmap(bootcr);
	}

	static void tnetd7200_set_clock(int base, struct tnetd7200_clock *clock,
	int prediv, int postdiv, int postdiv2, int mul, u32 frequency)
	{
	printk(KERN_INFO
	"Clocks: base = %d, frequency = %u, prediv = %d, "
	"postdiv = %d, postdiv2 = %d, mul = %d\n",
	base, frequency, prediv, postdiv, postdiv2, mul);

	writel(0, &clock->ctrl);
	writel(DIVISOR_ENABLE_MASK \| ((prediv - 1) & 0x1F), &clock->prediv);
	writel((mul - 1) & 0xF, &clock->mul);

	while (readl(&clock->status) & 0x1)
	; /* nop */

	writel(DIVISOR_ENABLE_MASK \| ((postdiv - 1) & 0x1F), &clock->postdiv);

	writel(readl(&clock->cmden) \| 1, &clock->cmden);
	writel(readl(&clock->cmd) \| 1, &clock->cmd);

	while (readl(&clock->status) & 0x1)
	; /* nop */

	writel(DIVISOR_ENABLE_MASK \| ((postdiv2 - 1) & 0x1F), &clock->postdiv2);

	writel(readl(&clock->cmden) \| 1, &clock->cmden);
	writel(readl(&clock->cmd) \| 1, &clock->cmd);

	while (readl(&clock->status) & 0x1)
	; /* nop */

	writel(readl(&clock->ctrl) \| 1, &clock->ctrl);
	}

	static int tnetd7200_get_clock_base(int clock_id, u32 *bootcr)
	{
	if (*bootcr & BOOT_PLL_ASYNC_MODE)
	/* Async */
	switch (clock_id) {
	case TNETD7200_CLOCK_ID_DSP:
	return AR7_REF_CLOCK;
	default:
	return AR7_AFE_CLOCK;
	}
	else
	/* Sync */
	if (*bootcr & BOOT_PLL_2TO1_MODE)
	/* 2:1 */
	switch (clock_id) {
	case TNETD7200_CLOCK_ID_DSP:
	return AR7_REF_CLOCK;
	default:
	return AR7_AFE_CLOCK;
	}
	else
	/* 1:1 */
	return AR7_REF_CLOCK;
	}


	static void __init tnetd7200_init_clocks(void)
	{
	u32 bootcr = (u32 )ioremap_nocache(AR7_REGS_DCL, 4);
	struct tnetd7200_clocks *clocks =
	ioremap_nocache(AR7_REGS_CLOCKS,
	sizeof(struct tnetd7200_clocks));
	int cpu_base, cpu_mul, cpu_prediv, cpu_postdiv;
	int dsp_base, dsp_mul, dsp_prediv, dsp_postdiv;
	int usb_base, usb_mul, usb_prediv, usb_postdiv;

	cpu_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_CPU, bootcr);
	dsp_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_DSP, bootcr);

	if (*bootcr & BOOT_PLL_ASYNC_MODE) {
	printk(KERN_INFO "Clocks: Async mode\n");

	printk(KERN_INFO "Clocks: Setting DSP clock\n");
	calculate(dsp_base, TNETD7200_DEF_DSP_CLK,
	&dsp_prediv, &dsp_postdiv, &dsp_mul);
	bus_clk.rate =
	((dsp_base / dsp_prediv) * dsp_mul) / dsp_postdiv;
	tnetd7200_set_clock(dsp_base, &clocks->dsp,
	dsp_prediv, dsp_postdiv * 2, dsp_postdiv, dsp_mul * 2,
	bus_clk.rate);

	printk(KERN_INFO "Clocks: Setting CPU clock\n");
	calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
	&cpu_postdiv, &cpu_mul);
	cpu_clk.rate =
	((cpu_base / cpu_prediv) * cpu_mul) / cpu_postdiv;
	tnetd7200_set_clock(cpu_base, &clocks->cpu,
	cpu_prediv, cpu_postdiv, -1, cpu_mul,
	cpu_clk.rate);

	} else
	if (*bootcr & BOOT_PLL_2TO1_MODE) {
	printk(KERN_INFO "Clocks: Sync 2:1 mode\n");

	printk(KERN_INFO "Clocks: Setting CPU clock\n");
	calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv,
	&cpu_postdiv, &cpu_mul);
	cpu_clk.rate = ((cpu_base / cpu_prediv) * cpu_mul)
	/ cpu_postdiv;
	tnetd7200_set_clock(cpu_base, &clocks->cpu,
	cpu_prediv, cpu_postdiv, -1, cpu_mul,
	cpu_clk.rate);

	printk(KERN_INFO "Clocks: Setting DSP clock\n");
	calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
	&dsp_postdiv, &dsp_mul);
	bus_clk.rate = cpu_clk.rate / 2;
	tnetd7200_set_clock(dsp_base, &clocks->dsp,
	dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
	dsp_mul * 2, bus_clk.rate);
	} else {
	printk(KERN_INFO "Clocks: Sync 1:1 mode\n");

	printk(KERN_INFO "Clocks: Setting DSP clock\n");
	calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv,
	&dsp_postdiv, &dsp_mul);
	bus_clk.rate = ((dsp_base / dsp_prediv) * dsp_mul)
	/ dsp_postdiv;
	tnetd7200_set_clock(dsp_base, &clocks->dsp,
	dsp_prediv, dsp_postdiv * 2, dsp_postdiv,
	dsp_mul * 2, bus_clk.rate);

	cpu_clk.rate = bus_clk.rate;
	}

	printk(KERN_INFO "Clocks: Setting USB clock\n");
	usb_base = bus_clk.rate;
	calculate(usb_base, TNETD7200_DEF_USB_CLK, &usb_prediv,
	&usb_postdiv, &usb_mul);
	tnetd7200_set_clock(usb_base, &clocks->usb,
	usb_prediv, usb_postdiv, -1, usb_mul,
	TNETD7200_DEF_USB_CLK);

	dsp_clk.rate = cpu_clk.rate;

	iounmap(clocks);
	iounmap(bootcr);
	}

	/*
	* Linux clock API
	*/
	int clk_enable(struct clk *clk)
	{
	return 0;
	}
	EXPORT_SYMBOL(clk_enable);

	void clk_disable(struct clk *clk)
	{
	}
	EXPORT_SYMBOL(clk_disable);

	unsigned long clk_get_rate(struct clk *clk)
	{
	if (!clk)
	return 0;

	return clk->rate;
	}
	EXPORT_SYMBOL(clk_get_rate);

	struct clk clk_get(struct device dev, const char *id)
	{
	if (!strcmp(id, "bus"))
	return &bus_clk;
	/* cpmac and vbus share the same rate */
	if (!strcmp(id, "cpmac"))
	return &vbus_clk;
	if (!strcmp(id, "cpu"))
	return &cpu_clk;
	if (!strcmp(id, "dsp"))
	return &dsp_clk;
	if (!strcmp(id, "vbus"))
	return &vbus_clk;
	return ERR_PTR(-ENOENT);
	}
	EXPORT_SYMBOL(clk_get);

	void clk_put(struct clk *clk)
	{
	}
	EXPORT_SYMBOL(clk_put);

	void __init ar7_init_clocks(void)
	{
	switch (ar7_chip_id()) {
	case AR7_CHIP_7100:
	case AR7_CHIP_7200:
	tnetd7200_init_clocks();
	break;
	case AR7_CHIP_7300:
	dsp_clk.rate = tnetd7300_dsp_clock();
	tnetd7300_init_clocks();
	break;
	default:
	break;
	}
	/* adjust vbus clock rate */
	vbus_clk.rate = bus_clk.rate / 2;
	}