diff options
Diffstat (limited to 'roms/u-boot/arch/arm/cpu/armv7/s5p-common/pwm.c')
| -rw-r--r-- | roms/u-boot/arch/arm/cpu/armv7/s5p-common/pwm.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/roms/u-boot/arch/arm/cpu/armv7/s5p-common/pwm.c b/roms/u-boot/arch/arm/cpu/armv7/s5p-common/pwm.c new file mode 100644 index 000000000..aef2e5574 --- /dev/null +++ b/roms/u-boot/arch/arm/cpu/armv7/s5p-common/pwm.c @@ -0,0 +1,225 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2011 Samsung Electronics + * + * Donghwa Lee <dh09.lee@samsung.com> + */ + +#include <common.h> +#include <errno.h> +#include <pwm.h> +#include <asm/io.h> +#include <asm/arch/pwm.h> +#include <asm/arch/clk.h> + +int pwm_enable(int pwm_id) +{ + const struct s5p_timer *pwm = +#if defined(CONFIG_ARCH_NEXELL) + (struct s5p_timer *)PHY_BASEADDR_PWM; +#else + (struct s5p_timer *)samsung_get_base_timer(); +#endif + unsigned long tcon; + + tcon = readl(&pwm->tcon); + tcon |= TCON_START(pwm_id); + + writel(tcon, &pwm->tcon); + + return 0; +} + +void pwm_disable(int pwm_id) +{ + const struct s5p_timer *pwm = +#if defined(CONFIG_ARCH_NEXELL) + (struct s5p_timer *)PHY_BASEADDR_PWM; +#else + (struct s5p_timer *)samsung_get_base_timer(); +#endif + unsigned long tcon; + + tcon = readl(&pwm->tcon); + tcon &= ~TCON_START(pwm_id); + + writel(tcon, &pwm->tcon); +} + +static unsigned long pwm_calc_tin(int pwm_id, unsigned long freq) +{ + unsigned long tin_parent_rate; + unsigned int div; + +#if defined(CONFIG_ARCH_NEXELL) + unsigned int pre_div; + const struct s5p_timer *pwm = + (struct s5p_timer *)PHY_BASEADDR_PWM; + unsigned int val; + struct clk *clk = clk_get(CORECLK_NAME_PCLK); + + tin_parent_rate = clk_get_rate(clk); +#else + tin_parent_rate = get_pwm_clk(); +#endif + +#if defined(CONFIG_ARCH_NEXELL) + writel(0, &pwm->tcfg0); + val = readl(&pwm->tcfg0); + + if (pwm_id < 2) + div = ((val >> 0) & 0xff) + 1; + else + div = ((val >> 8) & 0xff) + 1; + + writel(0, &pwm->tcfg1); + val = readl(&pwm->tcfg1); + val = (val >> MUX_DIV_SHIFT(pwm_id)) & 0xF; + pre_div = (1UL << val); + + freq = tin_parent_rate / div / pre_div; + + return freq; +#else + for (div = 2; div <= 16; div *= 2) { + if ((tin_parent_rate / (div << 16)) < freq) + return tin_parent_rate / div; + } + + return tin_parent_rate / 16; +#endif +} + +#define NS_IN_SEC 1000000000UL + +int pwm_config(int pwm_id, int duty_ns, int period_ns) +{ + const struct s5p_timer *pwm = +#if defined(CONFIG_ARCH_NEXELL) + (struct s5p_timer *)PHY_BASEADDR_PWM; +#else + (struct s5p_timer *)samsung_get_base_timer(); +#endif + unsigned int offset; + unsigned long tin_rate; + unsigned long tin_ns; + unsigned long frequency; + unsigned long tcon; + unsigned long tcnt; + unsigned long tcmp; + + /* + * We currently avoid using 64bit arithmetic by using the + * fact that anything faster than 1GHz is easily representable + * by 32bits. + */ + if (period_ns > NS_IN_SEC || duty_ns > NS_IN_SEC || period_ns == 0) + return -ERANGE; + + if (duty_ns > period_ns) + return -EINVAL; + + frequency = NS_IN_SEC / period_ns; + + /* Check to see if we are changing the clock rate of the PWM */ + tin_rate = pwm_calc_tin(pwm_id, frequency); + + tin_ns = NS_IN_SEC / tin_rate; + + if (IS_ENABLED(CONFIG_ARCH_NEXELL)) + /* The counter starts at zero. */ + tcnt = (period_ns / tin_ns) - 1; + else + tcnt = period_ns / tin_ns; + + /* Note, counters count down */ + tcmp = duty_ns / tin_ns; + tcmp = tcnt - tcmp; + + /* Update the PWM register block. */ + offset = pwm_id * 3; + if (pwm_id < 4) { + writel(tcnt, &pwm->tcntb0 + offset); + writel(tcmp, &pwm->tcmpb0 + offset); + } + + tcon = readl(&pwm->tcon); + tcon |= TCON_UPDATE(pwm_id); + if (pwm_id < 4) + tcon |= TCON_AUTO_RELOAD(pwm_id); + else + tcon |= TCON4_AUTO_RELOAD; + writel(tcon, &pwm->tcon); + + tcon &= ~TCON_UPDATE(pwm_id); + writel(tcon, &pwm->tcon); + + return 0; +} + +int pwm_init(int pwm_id, int div, int invert) +{ + u32 val; + const struct s5p_timer *pwm = +#if defined(CONFIG_ARCH_NEXELL) + (struct s5p_timer *)PHY_BASEADDR_PWM; +#else + (struct s5p_timer *)samsung_get_base_timer(); +#endif + unsigned long ticks_per_period; + unsigned int offset, prescaler; + + /* + * Timer Freq(HZ) = + * PWM_CLK / { (prescaler_value + 1) * (divider_value) } + */ + + val = readl(&pwm->tcfg0); + if (pwm_id < 2) { + prescaler = PRESCALER_0; + val &= ~0xff; + val |= (prescaler & 0xff); + } else { + prescaler = PRESCALER_1; + val &= ~(0xff << 8); + val |= (prescaler & 0xff) << 8; + } + writel(val, &pwm->tcfg0); + val = readl(&pwm->tcfg1); + val &= ~(0xf << MUX_DIV_SHIFT(pwm_id)); + val |= (div & 0xf) << MUX_DIV_SHIFT(pwm_id); + writel(val, &pwm->tcfg1); + + if (pwm_id == 4) { + /* + * TODO(sjg): Use this as a countdown timer for now. We count + * down from the maximum value to 0, then reset. + */ + ticks_per_period = -1UL; + } else { + const unsigned long pwm_hz = 1000; +#if defined(CONFIG_ARCH_NEXELL) + struct clk *clk = clk_get(CORECLK_NAME_PCLK); + unsigned long timer_rate_hz = clk_get_rate(clk) / +#else + unsigned long timer_rate_hz = get_pwm_clk() / +#endif + ((prescaler + 1) * (1 << div)); + + ticks_per_period = timer_rate_hz / pwm_hz; + } + + /* set count value */ + offset = pwm_id * 3; + + writel(ticks_per_period, &pwm->tcntb0 + offset); + + val = readl(&pwm->tcon) & ~(0xf << TCON_OFFSET(pwm_id)); + if (invert && (pwm_id < 4)) + val |= TCON_INVERTER(pwm_id); + writel(val, &pwm->tcon); + + pwm_enable(pwm_id); + + return 0; +} |