| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * (C) Copyright 2021 Xilinx, Inc. Michal Simek |
| */ |
| |
| #define LOG_CATEGORY UCLASS_PWM |
| |
| #include <clk.h> |
| #include <div64.h> |
| #include <dm.h> |
| #include <log.h> |
| #include <pwm.h> |
| #include <asm/io.h> |
| #include <log.h> |
| #include <div64.h> |
| #include <linux/bitfield.h> |
| #include <linux/math64.h> |
| #include <linux/log2.h> |
| #include <linux/time.h> |
| #include <dm/device_compat.h> |
| |
| #define CLOCK_CONTROL 0 |
| #define COUNTER_CONTROL 0xc |
| #define INTERVAL_COUNTER 0x24 |
| #define MATCH_1_COUNTER 0x30 |
| |
| #define CLK_FALLING_EDGE BIT(6) |
| #define CLK_SRC_EXTERNAL BIT(5) |
| #define CLK_PRESCALE_MASK GENMASK(4, 1) |
| #define CLK_PRESCALE_ENABLE BIT(0) |
| |
| #define COUNTER_WAVE_POL BIT(6) |
| #define COUNTER_WAVE_DISABLE BIT(5) |
| #define COUNTER_RESET BIT(4) |
| #define COUNTER_MATCH_ENABLE BIT(3) |
| #define COUNTER_DECREMENT_ENABLE BIT(2) |
| #define COUNTER_INTERVAL_ENABLE BIT(1) |
| #define COUNTER_COUNTING_DISABLE BIT(0) |
| |
| #define TTC_REG(reg, channel) ((reg) + (channel) * sizeof(u32)) |
| #define TTC_CLOCK_CONTROL(reg, channel) \ |
| TTC_REG((reg) + CLOCK_CONTROL, (channel)) |
| #define TTC_COUNTER_CONTROL(reg, channel) \ |
| TTC_REG((reg) + COUNTER_CONTROL, (channel)) |
| #define TTC_INTERVAL_COUNTER(reg, channel) \ |
| TTC_REG((reg) + INTERVAL_COUNTER, (channel)) |
| #define TTC_MATCH_1_COUNTER(reg, channel) \ |
| TTC_REG((reg) + MATCH_1_COUNTER, (channel)) |
| |
| struct cadence_ttc_pwm_plat { |
| u8 *regs; |
| u32 timer_width; |
| }; |
| |
| struct cadence_ttc_pwm_priv { |
| u8 *regs; |
| u32 timer_width; |
| u32 timer_mask; |
| unsigned long frequency; |
| bool invert[2]; |
| }; |
| |
| static int cadence_ttc_pwm_set_invert(struct udevice *dev, uint channel, |
| bool polarity) |
| { |
| struct cadence_ttc_pwm_priv *priv = dev_get_priv(dev); |
| |
| if (channel > 2) { |
| dev_err(dev, "Unsupported channel number %d(max 2)\n", channel); |
| return -EINVAL; |
| } |
| |
| priv->invert[channel] = polarity; |
| |
| dev_dbg(dev, "polarity=%u. Please config PWM again\n", polarity); |
| |
| return 0; |
| } |
| |
| static int cadence_ttc_pwm_set_config(struct udevice *dev, uint channel, |
| uint period_ns, uint duty_ns) |
| { |
| struct cadence_ttc_pwm_priv *priv = dev_get_priv(dev); |
| u32 counter_ctrl, clock_ctrl; |
| int period_clocks, duty_clocks, prescaler; |
| |
| dev_dbg(dev, "channel %d, duty %d/period %d ns\n", channel, |
| duty_ns, period_ns); |
| |
| if (channel > 2) { |
| dev_err(dev, "Unsupported channel number %d(max 2)\n", channel); |
| return -EINVAL; |
| } |
| |
| /* Make sure counter is stopped */ |
| counter_ctrl = readl(TTC_COUNTER_CONTROL(priv->regs, channel)); |
| setbits_le32(TTC_COUNTER_CONTROL(priv->regs, channel), |
| COUNTER_COUNTING_DISABLE | COUNTER_WAVE_DISABLE); |
| |
| /* Calculate period, prescaler and set clock control register */ |
| period_clocks = div64_u64(((int64_t)period_ns * priv->frequency), |
| NSEC_PER_SEC); |
| |
| prescaler = ilog2(period_clocks) + 1 - priv->timer_width; |
| if (prescaler < 0) |
| prescaler = 0; |
| |
| clock_ctrl = readl(TTC_CLOCK_CONTROL(priv->regs, channel)); |
| |
| if (!prescaler) { |
| clock_ctrl &= ~(CLK_PRESCALE_ENABLE | CLK_PRESCALE_MASK); |
| } else { |
| clock_ctrl &= ~CLK_PRESCALE_MASK; |
| clock_ctrl |= CLK_PRESCALE_ENABLE; |
| clock_ctrl |= FIELD_PREP(CLK_PRESCALE_MASK, prescaler - 1); |
| }; |
| |
| /* External source is not handled by this driver now */ |
| clock_ctrl &= ~CLK_SRC_EXTERNAL; |
| |
| writel(clock_ctrl, TTC_CLOCK_CONTROL(priv->regs, channel)); |
| |
| /* Calculate interval and set counter control value */ |
| duty_clocks = div64_u64(((int64_t)duty_ns * priv->frequency), |
| NSEC_PER_SEC); |
| |
| writel((period_clocks >> prescaler) & priv->timer_mask, |
| TTC_INTERVAL_COUNTER(priv->regs, channel)); |
| writel((duty_clocks >> prescaler) & priv->timer_mask, |
| TTC_MATCH_1_COUNTER(priv->regs, channel)); |
| |
| /* Restore/reset counter */ |
| counter_ctrl &= ~COUNTER_DECREMENT_ENABLE; |
| counter_ctrl |= COUNTER_INTERVAL_ENABLE | |
| COUNTER_RESET | |
| COUNTER_MATCH_ENABLE; |
| |
| if (priv->invert[channel]) |
| counter_ctrl |= COUNTER_WAVE_POL; |
| else |
| counter_ctrl &= ~COUNTER_WAVE_POL; |
| |
| writel(counter_ctrl, TTC_COUNTER_CONTROL(priv->regs, channel)); |
| |
| dev_dbg(dev, "%d/%d clocks, prescaler 2^%d\n", duty_clocks, |
| period_clocks, prescaler); |
| |
| return 0; |
| }; |
| |
| static int cadence_ttc_pwm_set_enable(struct udevice *dev, uint channel, |
| bool enable) |
| { |
| struct cadence_ttc_pwm_priv *priv = dev_get_priv(dev); |
| |
| if (channel > 2) { |
| dev_err(dev, "Unsupported channel number %d(max 2)\n", channel); |
| return -EINVAL; |
| } |
| |
| dev_dbg(dev, "Enable: %d, channel %d\n", enable, channel); |
| |
| if (enable) { |
| clrbits_le32(TTC_COUNTER_CONTROL(priv->regs, channel), |
| COUNTER_COUNTING_DISABLE | |
| COUNTER_WAVE_DISABLE); |
| setbits_le32(TTC_COUNTER_CONTROL(priv->regs, channel), |
| COUNTER_RESET); |
| } else { |
| setbits_le32(TTC_COUNTER_CONTROL(priv->regs, channel), |
| COUNTER_COUNTING_DISABLE | |
| COUNTER_WAVE_DISABLE); |
| } |
| |
| return 0; |
| }; |
| |
| static int cadence_ttc_pwm_probe(struct udevice *dev) |
| { |
| struct cadence_ttc_pwm_priv *priv = dev_get_priv(dev); |
| struct cadence_ttc_pwm_plat *plat = dev_get_plat(dev); |
| struct clk clk; |
| int ret; |
| |
| priv->regs = plat->regs; |
| priv->timer_width = plat->timer_width; |
| priv->timer_mask = GENMASK(priv->timer_width - 1, 0); |
| |
| ret = clk_get_by_index(dev, 0, &clk); |
| if (ret < 0) { |
| dev_err(dev, "failed to get clock\n"); |
| return ret; |
| } |
| |
| priv->frequency = clk_get_rate(&clk); |
| if (IS_ERR_VALUE(priv->frequency)) { |
| dev_err(dev, "failed to get rate\n"); |
| return priv->frequency; |
| } |
| dev_dbg(dev, "Clk frequency: %ld\n", priv->frequency); |
| |
| ret = clk_enable(&clk); |
| if (ret) { |
| dev_err(dev, "failed to enable clock\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int cadence_ttc_pwm_of_to_plat(struct udevice *dev) |
| { |
| struct cadence_ttc_pwm_plat *plat = dev_get_plat(dev); |
| const char *cells; |
| |
| cells = dev_read_prop(dev, "#pwm-cells", NULL); |
| if (!cells) |
| return -EINVAL; |
| |
| plat->regs = dev_read_addr_ptr(dev); |
| |
| plat->timer_width = dev_read_u32_default(dev, "timer-width", 16); |
| |
| return 0; |
| } |
| |
| static int cadence_ttc_pwm_bind(struct udevice *dev) |
| { |
| const char *cells; |
| |
| cells = dev_read_prop(dev, "#pwm-cells", NULL); |
| if (!cells) |
| return -ENODEV; |
| |
| return 0; |
| } |
| |
| static const struct pwm_ops cadence_ttc_pwm_ops = { |
| .set_invert = cadence_ttc_pwm_set_invert, |
| .set_config = cadence_ttc_pwm_set_config, |
| .set_enable = cadence_ttc_pwm_set_enable, |
| }; |
| |
| static const struct udevice_id cadence_ttc_pwm_ids[] = { |
| { .compatible = "cdns,ttc" }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(cadence_ttc_pwm) = { |
| .name = "cadence_ttc_pwm", |
| .id = UCLASS_PWM, |
| .of_match = cadence_ttc_pwm_ids, |
| .ops = &cadence_ttc_pwm_ops, |
| .bind = cadence_ttc_pwm_bind, |
| .of_to_plat = cadence_ttc_pwm_of_to_plat, |
| .probe = cadence_ttc_pwm_probe, |
| .priv_auto = sizeof(struct cadence_ttc_pwm_priv), |
| .plat_auto = sizeof(struct cadence_ttc_pwm_plat), |
| }; |