| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474 | /* linux/arch/arm/plat-s3c24xx/pwm-clock.c * * Copyright (c) 2007 Simtec Electronics * Copyright (c) 2007, 2008 Ben Dooks *	Ben Dooks <ben-linux@fluff.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.*/#include <linux/init.h>#include <linux/module.h>#include <linux/kernel.h>#include <linux/list.h>#include <linux/errno.h>#include <linux/log2.h>#include <linux/clk.h>#include <linux/err.h>#include <linux/io.h>#include <mach/hardware.h>#include <mach/map.h>#include <asm/irq.h>#include <plat/clock.h>#include <plat/cpu.h>#include <plat/regs-timer.h>#include <plat/pwm-clock.h>/* Each of the timers 0 through 5 go through the following * clock tree, with the inputs depending on the timers. * * pclk ---- [ prescaler 0 ] -+---> timer 0 *			      +---> timer 1 * * pclk ---- [ prescaler 1 ] -+---> timer 2 *			      +---> timer 3 *			      \---> timer 4 * * Which are fed into the timers as so: * * prescaled 0 ---- [ div 2,4,8,16 ] ---\ *				       [mux] -> timer 0 * tclk 0 ------------------------------/ * * prescaled 0 ---- [ div 2,4,8,16 ] ---\ *				       [mux] -> timer 1 * tclk 0 ------------------------------/ * * * prescaled 1 ---- [ div 2,4,8,16 ] ---\ *				       [mux] -> timer 2 * tclk 1 ------------------------------/ * * prescaled 1 ---- [ div 2,4,8,16 ] ---\ *				       [mux] -> timer 3 * tclk 1 ------------------------------/ * * prescaled 1 ---- [ div 2,4,8, 16 ] --\ *				       [mux] -> timer 4 * tclk 1 ------------------------------/ * * Since the mux and the divider are tied together in the * same register space, it is impossible to set the parent * and the rate at the same time. To avoid this, we add an * intermediate 'prescaled-and-divided' clock to select * as the parent for the timer input clock called tdiv. * * prescaled clk --> pwm-tdiv ---\ *                             [ mux ] --> timer X * tclk -------------------------/*/static struct clk clk_timer_scaler[];static unsigned long clk_pwm_scaler_get_rate(struct clk *clk){	unsigned long tcfg0 = __raw_readl(S3C2410_TCFG0);	if (clk == &clk_timer_scaler[1]) {		tcfg0 &= S3C2410_TCFG_PRESCALER1_MASK;		tcfg0 >>= S3C2410_TCFG_PRESCALER1_SHIFT;	} else {		tcfg0 &= S3C2410_TCFG_PRESCALER0_MASK;	}	return clk_get_rate(clk->parent) / (tcfg0 + 1);}static unsigned long clk_pwm_scaler_round_rate(struct clk *clk,					       unsigned long rate){	unsigned long parent_rate = clk_get_rate(clk->parent);	unsigned long divisor = parent_rate / rate;	if (divisor > 256)		divisor = 256;	else if (divisor < 2)		divisor = 2;	return parent_rate / divisor;}static int clk_pwm_scaler_set_rate(struct clk *clk, unsigned long rate){	unsigned long round = clk_pwm_scaler_round_rate(clk, rate);	unsigned long tcfg0;	unsigned long divisor;	unsigned long flags;	divisor = clk_get_rate(clk->parent) / round;	divisor--;	local_irq_save(flags);	tcfg0 = __raw_readl(S3C2410_TCFG0);	if (clk == &clk_timer_scaler[1]) {		tcfg0 &= ~S3C2410_TCFG_PRESCALER1_MASK;		tcfg0 |= divisor << S3C2410_TCFG_PRESCALER1_SHIFT;	} else {		tcfg0 &= ~S3C2410_TCFG_PRESCALER0_MASK;		tcfg0 |= divisor;	}	__raw_writel(tcfg0, S3C2410_TCFG0);	local_irq_restore(flags);	return 0;}static struct clk_ops clk_pwm_scaler_ops = {	.get_rate	= clk_pwm_scaler_get_rate,	.set_rate	= clk_pwm_scaler_set_rate,	.round_rate	= clk_pwm_scaler_round_rate,};static struct clk clk_timer_scaler[] = {	[0]	= {		.name		= "pwm-scaler0",		.id		= -1,		.ops		= &clk_pwm_scaler_ops,	},	[1]	= {		.name		= "pwm-scaler1",		.id		= -1,		.ops		= &clk_pwm_scaler_ops,	},};static struct clk clk_timer_tclk[] = {	[0]	= {		.name		= "pwm-tclk0",		.id		= -1,	},	[1]	= {		.name		= "pwm-tclk1",		.id		= -1,	},};struct pwm_tdiv_clk {	struct clk	clk;	unsigned int	divisor;};static inline struct pwm_tdiv_clk *to_tdiv(struct clk *clk){	return container_of(clk, struct pwm_tdiv_clk, clk);}static unsigned long clk_pwm_tdiv_get_rate(struct clk *clk){	unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);	unsigned int divisor;	tcfg1 >>= S3C2410_TCFG1_SHIFT(clk->id);	tcfg1 &= S3C2410_TCFG1_MUX_MASK;	if (pwm_cfg_src_is_tclk(tcfg1))		divisor = to_tdiv(clk)->divisor;	else		divisor = tcfg_to_divisor(tcfg1);	return clk_get_rate(clk->parent) / divisor;}static unsigned long clk_pwm_tdiv_round_rate(struct clk *clk,					     unsigned long rate){	unsigned long parent_rate;	unsigned long divisor;	parent_rate = clk_get_rate(clk->parent);	divisor = parent_rate / rate;	if (divisor <= 1 && pwm_tdiv_has_div1())		divisor = 1;	else if (divisor <= 2)		divisor = 2;	else if (divisor <= 4)		divisor = 4;	else if (divisor <= 8)		divisor = 8;	else		divisor = 16;	return parent_rate / divisor;}static unsigned long clk_pwm_tdiv_bits(struct pwm_tdiv_clk *divclk){	return pwm_tdiv_div_bits(divclk->divisor);}static void clk_pwm_tdiv_update(struct pwm_tdiv_clk *divclk){	unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);	unsigned long bits = clk_pwm_tdiv_bits(divclk);	unsigned long flags;	unsigned long shift =  S3C2410_TCFG1_SHIFT(divclk->clk.id);	local_irq_save(flags);	tcfg1 = __raw_readl(S3C2410_TCFG1);	tcfg1 &= ~(S3C2410_TCFG1_MUX_MASK << shift);	tcfg1 |= bits << shift;	__raw_writel(tcfg1, S3C2410_TCFG1);	local_irq_restore(flags);}static int clk_pwm_tdiv_set_rate(struct clk *clk, unsigned long rate){	struct pwm_tdiv_clk *divclk = to_tdiv(clk);	unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);	unsigned long parent_rate = clk_get_rate(clk->parent);	unsigned long divisor;	tcfg1 >>= S3C2410_TCFG1_SHIFT(clk->id);	tcfg1 &= S3C2410_TCFG1_MUX_MASK;	rate = clk_round_rate(clk, rate);	divisor = parent_rate / rate;	if (divisor > 16)		return -EINVAL;	divclk->divisor = divisor;	/* Update the current MUX settings if we are currently	 * selected as the clock source for this clock. */	if (!pwm_cfg_src_is_tclk(tcfg1))		clk_pwm_tdiv_update(divclk);	return 0;}static struct clk_ops clk_tdiv_ops = {	.get_rate	= clk_pwm_tdiv_get_rate,	.set_rate	= clk_pwm_tdiv_set_rate,	.round_rate	= clk_pwm_tdiv_round_rate,};static struct pwm_tdiv_clk clk_timer_tdiv[] = {	[0]	= {		.clk	= {			.name	= "pwm-tdiv",			.devname	= "s3c24xx-pwm.0",			.ops	= &clk_tdiv_ops,			.parent	= &clk_timer_scaler[0],		},	},	[1]	= {		.clk	= {			.name	= "pwm-tdiv",			.devname	= "s3c24xx-pwm.1",			.ops	= &clk_tdiv_ops,			.parent	= &clk_timer_scaler[0],		}	},	[2]	= {		.clk	= {			.name	= "pwm-tdiv",			.devname	= "s3c24xx-pwm.2",			.ops	= &clk_tdiv_ops,			.parent	= &clk_timer_scaler[1],		},	},	[3]	= {		.clk	= {			.name	= "pwm-tdiv",			.devname	= "s3c24xx-pwm.3",			.ops	= &clk_tdiv_ops,			.parent	= &clk_timer_scaler[1],		},	},	[4]	= {		.clk	= {			.name	= "pwm-tdiv",			.devname	= "s3c24xx-pwm.4",			.ops	= &clk_tdiv_ops,			.parent	= &clk_timer_scaler[1],		},	},};static int __init clk_pwm_tdiv_register(unsigned int id){	struct pwm_tdiv_clk *divclk = &clk_timer_tdiv[id];	unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);	tcfg1 >>= S3C2410_TCFG1_SHIFT(id);	tcfg1 &= S3C2410_TCFG1_MUX_MASK;	divclk->clk.id = id;	divclk->divisor = tcfg_to_divisor(tcfg1);	return s3c24xx_register_clock(&divclk->clk);}static inline struct clk *s3c24xx_pwmclk_tclk(unsigned int id){	return (id >= 2) ? &clk_timer_tclk[1] : &clk_timer_tclk[0];}static inline struct clk *s3c24xx_pwmclk_tdiv(unsigned int id){	return &clk_timer_tdiv[id].clk;}static int clk_pwm_tin_set_parent(struct clk *clk, struct clk *parent){	unsigned int id = clk->id;	unsigned long tcfg1;	unsigned long flags;	unsigned long bits;	unsigned long shift = S3C2410_TCFG1_SHIFT(id);	unsigned long mux_tclk;	if (soc_is_s3c24xx())		mux_tclk = S3C2410_TCFG1_MUX_TCLK;	else if (soc_is_s5p6440() || soc_is_s5p6450())		mux_tclk = 0;	else		mux_tclk = S3C64XX_TCFG1_MUX_TCLK;	if (parent == s3c24xx_pwmclk_tclk(id))		bits = mux_tclk << shift;	else if (parent == s3c24xx_pwmclk_tdiv(id))		bits = clk_pwm_tdiv_bits(to_tdiv(parent)) << shift;	else		return -EINVAL;	clk->parent = parent;	local_irq_save(flags);	tcfg1 = __raw_readl(S3C2410_TCFG1);	tcfg1 &= ~(S3C2410_TCFG1_MUX_MASK << shift);	__raw_writel(tcfg1 | bits, S3C2410_TCFG1);	local_irq_restore(flags);	return 0;}static struct clk_ops clk_tin_ops = {	.set_parent	= clk_pwm_tin_set_parent,};static struct clk clk_tin[] = {	[0]	= {		.name	= "pwm-tin",		.devname	= "s3c24xx-pwm.0",		.id	= 0,		.ops	= &clk_tin_ops,	},	[1]	= {		.name	= "pwm-tin",		.devname	= "s3c24xx-pwm.1",		.id	= 1,		.ops	= &clk_tin_ops,	},	[2]	= {		.name	= "pwm-tin",		.devname	= "s3c24xx-pwm.2",		.id	= 2,		.ops	= &clk_tin_ops,	},	[3]	= {		.name	= "pwm-tin",		.devname	= "s3c24xx-pwm.3",		.id	= 3,		.ops	= &clk_tin_ops,	},	[4]	= {		.name	= "pwm-tin",		.devname	= "s3c24xx-pwm.4",		.id	= 4,		.ops	= &clk_tin_ops,	},};static __init int clk_pwm_tin_register(struct clk *pwm){	unsigned long tcfg1 = __raw_readl(S3C2410_TCFG1);	unsigned int id = pwm->id;	struct clk *parent;	int ret;	ret = s3c24xx_register_clock(pwm);	if (ret < 0)		return ret;	tcfg1 >>= S3C2410_TCFG1_SHIFT(id);	tcfg1 &= S3C2410_TCFG1_MUX_MASK;	if (pwm_cfg_src_is_tclk(tcfg1))		parent = s3c24xx_pwmclk_tclk(id);	else		parent = s3c24xx_pwmclk_tdiv(id);	return clk_set_parent(pwm, parent);}/** * s3c_pwmclk_init() - initialise pwm clocks * * Initialise and register the clocks which provide the inputs for the * pwm timer blocks. * * Note, this call is required by the time core, so must be called after * the base clocks are added and before any of the initcalls are run. */__init void s3c_pwmclk_init(void){	struct clk *clk_timers;	unsigned int clk;	int ret;	clk_timers = clk_get(NULL, "timers");	if (IS_ERR(clk_timers)) {		printk(KERN_ERR "%s: no parent clock\n", __func__);		return;	}	for (clk = 0; clk < ARRAY_SIZE(clk_timer_scaler); clk++)		clk_timer_scaler[clk].parent = clk_timers;	s3c_register_clocks(clk_timer_scaler, ARRAY_SIZE(clk_timer_scaler));	s3c_register_clocks(clk_timer_tclk, ARRAY_SIZE(clk_timer_tclk));	for (clk = 0; clk < ARRAY_SIZE(clk_timer_tdiv); clk++) {		ret = clk_pwm_tdiv_register(clk);		if (ret < 0) {			printk(KERN_ERR "error adding pwm%d tdiv clock\n", clk);			return;		}	}	for (clk = 0; clk < ARRAY_SIZE(clk_tin); clk++) {		ret = clk_pwm_tin_register(&clk_tin[clk]);		if (ret < 0) {			printk(KERN_ERR "error adding pwm%d tin clock\n", clk);			return;		}	}}
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