+++ /dev/null
-/* 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;
- }
- }
-}
projects / cascardo / linux.git / commitdiff