On Thu, Mar 14, 2024 at 06:01:31PM +0800, Jingbao Qiu wrote: > Implement the PWM driver for CV1800. > > Signed-off-by: Jingbao Qiu <qiujingbao.dlmu@xxxxxxxxx> > --- > drivers/pwm/Kconfig | 10 ++ > drivers/pwm/Makefile | 1 + > drivers/pwm/pwm-cv1800.c | 315 +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 326 insertions(+) > create mode 100644 drivers/pwm/pwm-cv1800.c > > diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig > index 4b956d661755..455f07af94f7 100644 > --- a/drivers/pwm/Kconfig > +++ b/drivers/pwm/Kconfig > @@ -186,6 +186,16 @@ config PWM_CROS_EC > PWM driver for exposing a PWM attached to the ChromeOS Embedded > Controller. > > +config PWM_CV1800 > + tristate "Sophgo CV1800 PWM driver" > + depends on ARCH_SOPHGO || COMPILE_TEST > + help > + Generic PWM framework driver for the Sophgo CV1800 series > + SoCs. > + > + To compile this driver as a module, build the dependecies > + as modules, this will be called pwm-cv1800. > + > config PWM_DWC_CORE > tristate > depends on HAS_IOMEM > diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile > index c5ec9e168ee7..6c3c4a07a316 100644 > --- a/drivers/pwm/Makefile > +++ b/drivers/pwm/Makefile > @@ -15,6 +15,7 @@ obj-$(CONFIG_PWM_CLK) += pwm-clk.o > obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o > obj-$(CONFIG_PWM_CRC) += pwm-crc.o > obj-$(CONFIG_PWM_CROS_EC) += pwm-cros-ec.o > +obj-$(CONFIG_PWM_CV1800) += pwm-cv1800.o > obj-$(CONFIG_PWM_DWC_CORE) += pwm-dwc-core.o > obj-$(CONFIG_PWM_DWC) += pwm-dwc.o > obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o > diff --git a/drivers/pwm/pwm-cv1800.c b/drivers/pwm/pwm-cv1800.c > new file mode 100644 > index 000000000000..8eca07c60942 > --- /dev/null > +++ b/drivers/pwm/pwm-cv1800.c > @@ -0,0 +1,315 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Sophgo CV1800 PWM driver > + * Author: Jingbao Qiu <qiujingbao.dlmu@xxxxxxxxx> > + * > + * Limitations: > + * - It output low when PWM channel disabled. > + * - This pwm device supports dynamic loading of PWM parameters. When PWMSTART > + * is written from 0 to 1, the register value (HLPERIODn, PERIODn) will be > + * temporarily stored inside the PWM. If you want to dynamically change the > + * waveform during PWM output, after writing the new value to HLPERIODn and > + * PERIODn, write 1 and then 0 to PWMUPDATE[n] to make the new value effective. > + * - Supports up to Rate/2 output, and the lowest is about Rate/(2^30-1). > + * - By setting HLPERIODn to 0, can produce 100% duty cycle. > + * - This hardware could support inverted polarity. By default, the value of the > + * POLARITY register is 0x0. This means that HLPERIOD represents the number > + * of low level beats. > + * - This hardware supports input mode and output mode, implemented through the > + * Output-Enable/OE register. However, this driver has not yet implemented > + * capture callback. > + */ > + > +#include <linux/clk.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/pwm.h> > +#include <linux/regmap.h> > + > +#define PWM_CV1800_HLPERIOD_BASE 0x00 > +#define PWM_CV1800_PERIOD_BASE 0x04 > +#define PWM_CV1800_POLARITY 0x40 > +#define PWM_CV1800_START 0x44 > +#define PWM_CV1800_DONE 0x48 > +#define PWM_CV1800_UPDATE 0x4c > +#define PWM_CV1800_OE 0xd0 > + > +#define PWM_CV1800_HLPERIOD(n) (PWM_CV1800_HLPERIOD_BASE + ((n) * 0x08)) > +#define PWM_CV1800_PERIOD(n) (PWM_CV1800_PERIOD_BASE + ((n) * 0x08)) > + > +#define PWM_CV1800_UPDATE_MASK(n) (BIT(0) << (n)) > +#define PWM_CV1800_OE_MASK(n) (BIT(0) << (n)) > +#define PWM_CV1800_START_MASK(n) (BIT(0) << (n)) > +#define PWM_CV1800_POLARITY_MASK(n) (BIT(0) << (n)) > + > +#define PWM_CV1800_MAXPERIOD 0x3fffffff > +#define PWM_CV1800_MINPERIOD 2 > +#define PWM_CV1800_CHANNELS 4 > +#define PWM_CV1800_PERIOD_RESET BIT(1) > +#define PWM_CV1800_HLPERIOD_RESET BIT(0) > +#define PWM_CV1800_REG_DISABLE 0x00U > +#define PWM_CV1800_REG_ENABLE(n) (BIT(0) << (n)) > + > +struct cv1800_pwm { > + struct regmap *map; > + struct clk *clk; > + unsigned long clk_rate; > +}; > + > +static inline struct cv1800_pwm *to_cv1800_pwm_dev(struct pwm_chip *chip) > +{ > + return pwmchip_get_drvdata(chip); > +} > + > +static const struct regmap_config cv1800_pwm_regmap_config = { > + .reg_bits = 32, > + .val_bits = 32, > + .reg_stride = 4, > +}; > + > +static int cv1800_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, > + bool enable) > +{ > + struct cv1800_pwm *priv = to_cv1800_pwm_dev(chip); > + u32 pwm_enable; > + > + regmap_read(priv->map, PWM_CV1800_START, &pwm_enable); > + pwm_enable &= PWM_CV1800_START_MASK(pwm->hwpwm); > + > + /* > + * If the parameters are changed during runtime, Register needs > + * to be updated to take effect. > + */ > + if (pwm_enable && enable) { > + regmap_update_bits(priv->map, PWM_CV1800_UPDATE, > + PWM_CV1800_UPDATE_MASK(pwm->hwpwm), > + PWM_CV1800_REG_ENABLE(pwm->hwpwm)); > + regmap_update_bits(priv->map, PWM_CV1800_UPDATE, > + PWM_CV1800_UPDATE_MASK(pwm->hwpwm), > + PWM_CV1800_REG_DISABLE); > + } else if (!pwm_enable && enable) { > + regmap_update_bits(priv->map, PWM_CV1800_START, > + PWM_CV1800_START_MASK(pwm->hwpwm), > + PWM_CV1800_REG_ENABLE(pwm->hwpwm)); > + } else if (pwm_enable && !enable) { > + regmap_update_bits(priv->map, PWM_CV1800_START, > + PWM_CV1800_START_MASK(pwm->hwpwm), > + PWM_CV1800_REG_DISABLE); > + } > + > + return 0; > +} > + > +static void cv1800_pwm_set_polarity(struct pwm_chip *chip, > + struct pwm_device *pwm, > + enum pwm_polarity polarity) > +{ > + struct cv1800_pwm *priv = to_cv1800_pwm_dev(chip); > + u32 config_polarity = 0; > + > + if (pwm->state.enabled) > + cv1800_pwm_enable(chip, pwm, !pwm->state.enabled); > + > + if (polarity == PWM_POLARITY_INVERSED) > + config_polarity = PWM_CV1800_POLARITY_MASK(pwm->hwpwm); > + > + regmap_update_bits(priv->map, PWM_CV1800_POLARITY, > + PWM_CV1800_POLARITY_MASK(pwm->hwpwm), > + config_polarity); > +} > + > +/** > + * cv1800_pwm_set_oe() - check and config nth channal output-enable/OE mode > + * @chip: PWM chip > + * @pwm: PWM device > + * @mode: The nth bit of the mode represents the output-enable/OE mode > + * of the nth channal. 1 represents output mode, 0 represents > + * input mode. > + */ > +static void cv1800_pwm_set_oe(struct pwm_chip *chip, struct pwm_device *pwm, > + u32 mode) Did you get any information about the capture support pwm controller? > +{ > + struct cv1800_pwm *priv = to_cv1800_pwm_dev(chip); > + u32 state; > + > + regmap_read(priv->map, PWM_CV1800_OE, &state); > + state &= PWM_CV1800_OE_MASK(pwm->hwpwm); > + > + if (state == mode) > + return; > + > + /* disenable pwm output before changing output mode */ > + cv1800_pwm_enable(chip, pwm, false); > + > + regmap_update_bits(priv->map, PWM_CV1800_OE, > + PWM_CV1800_OE_MASK(pwm->hwpwm), mode); > +} > + > +static int cv1800_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, > + const struct pwm_state *state) > +{ > + struct cv1800_pwm *priv = to_cv1800_pwm_dev(chip); > + u32 period_val, hlperiod_val; > + u64 ticks; > + > + cv1800_pwm_set_oe(chip, pwm, PWM_CV1800_OE_MASK(pwm->hwpwm)); If no capture support, I don't think we need to take care OE, could it be done during init? > + > + if (state->polarity != pwm->state.polarity) > + cv1800_pwm_set_polarity(chip, pwm, state->polarity); > + > + /* > + * This hardware use PERIOD and HLPERIOD registers to represent PWM waves. > + * > + * The meaning of PERIOD is how many clock cycles (from the clock source) > + * are used to represent PWM waves. > + * PERIOD = rate(MHz) / target(MHz) > + * PERIOD = period(ns) * rate(Hz) / NSEC_PER_SEC > + */ > + ticks = mul_u64_u64_div_u64(state->period, priv->clk_rate, > + NSEC_PER_SEC); > + if (ticks < PWM_CV1800_MINPERIOD) > + return -EINVAL; > + > + if (ticks > PWM_CV1800_MAXPERIOD) > + ticks = PWM_CV1800_MAXPERIOD; > + period_val = (u32)ticks; > + > + /* > + * After mapping, hlperiod represents the same polarity as duty. > + * HLPERIOD = rate(MHz) / duty(MHz) > + * HLPERIOD = duty(ns) * rate(Hz) / NSEC_PER_SEC > + */ > + ticks = mul_u64_u64_div_u64(state->duty_cycle, priv->clk_rate, > + NSEC_PER_SEC); > + if (ticks > period_val) > + ticks = period_val; > + hlperiod_val = (u32)ticks; > + > + regmap_write(priv->map, PWM_CV1800_PERIOD(pwm->hwpwm), period_val); > + regmap_write(priv->map, PWM_CV1800_HLPERIOD(pwm->hwpwm), hlperiod_val); > + > + cv1800_pwm_enable(chip, pwm, state->enabled); > + > + return 0; > +} > + > +static int cv1800_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, > + struct pwm_state *state) > +{ > + struct cv1800_pwm *priv = to_cv1800_pwm_dev(chip); > + u32 period_val, hlperiod_val; > + u64 period_ns = 0, duty_ns = 0; > + u32 enable = 0, polarity = 0; > + > + regmap_read(priv->map, PWM_CV1800_PERIOD(pwm->hwpwm), &period_val); > + regmap_read(priv->map, PWM_CV1800_HLPERIOD(pwm->hwpwm), &hlperiod_val); > + > + if (period_val != PWM_CV1800_PERIOD_RESET || > + hlperiod_val != PWM_CV1800_HLPERIOD_RESET) { > + period_ns = DIV_ROUND_UP_ULL(period_val * NSEC_PER_SEC, > + priv->clk_rate); > + duty_ns = DIV_ROUND_UP_ULL(hlperiod_val * NSEC_PER_SEC, > + priv->clk_rate); > + > + regmap_read(priv->map, PWM_CV1800_START, &enable); > + enable &= PWM_CV1800_START_MASK(pwm->hwpwm); > + > + regmap_read(priv->map, PWM_CV1800_POLARITY, &polarity); > + polarity &= PWM_CV1800_POLARITY_MASK(pwm->hwpwm); > + } > + > + state->period = period_ns; > + state->duty_cycle = duty_ns; > + state->enabled = enable; > + > + /* > + * To ensure that duty and hlperiod represent the same polarity > + * the following mapping needs to be completed. > + * > + * |----------|------------|------------|-----------| > + * | Linux | register | duty | register | > + * | polarity | polarity | | hlperiod | > + * |----------|------------|------------|-----------| > + * | 1 | 0 | low level | low level | > + * |----------|------------|------------|-----------| > + * | 0 | 1 | high level | high level| > + * |----------|------------|------------|-----------| > + */ > + state->polarity = polarity ? PWM_POLARITY_NORMAL : > + PWM_POLARITY_INVERSED; > + > + return 0; > +} > + > +static const struct pwm_ops cv1800_pwm_ops = { > + .apply = cv1800_pwm_apply, > + .get_state = cv1800_pwm_get_state, > +}; > + > +static int cv1800_pwm_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct cv1800_pwm *priv; > + struct pwm_chip *chip; > + void __iomem *base; > + int ret; > + > + chip = devm_pwmchip_alloc(dev, PWM_CV1800_CHANNELS, sizeof(*priv)); > + if (!chip) > + return PTR_ERR(chip); > + priv = to_cv1800_pwm_dev(chip); > + > + base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(base)) > + return PTR_ERR(base); > + > + priv->map = devm_regmap_init_mmio(&pdev->dev, base, > + &cv1800_pwm_regmap_config); > + if (IS_ERR(priv->map)) > + return PTR_ERR(priv->map); > + > + priv->clk = devm_clk_get_enabled(&pdev->dev, NULL); > + if (IS_ERR(priv->clk)) > + return dev_err_probe(&pdev->dev, PTR_ERR(priv->clk), > + "clk not found\n"); > + > + ret = devm_clk_rate_exclusive_get(dev, priv->clk); > + if (ret) > + return dev_err_probe(&pdev->dev, ret, > + "failed to get exclusive rate\n"); > + > + priv->clk_rate = clk_get_rate(priv->clk); > + if (!priv->clk_rate) > + return dev_err_probe(&pdev->dev, -EINVAL, > + "Invalid clock rate: %lu\n", > + priv->clk_rate); > + > + chip->ops = &cv1800_pwm_ops; > + > + ret = devm_pwmchip_add(dev, chip); > + if (ret) > + return dev_err_probe(dev, ret, "Failed to add PWM chip\n"); > + > + return 0; > +} > + > +static const struct of_device_id cv1800_pwm_dt_ids[] = { > + { .compatible = "sophgo,cv1800-pwm" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, cv1800_pwm_dt_ids); > + > +static struct platform_driver cv1800_pwm_driver = { > + .probe = cv1800_pwm_probe, > + .driver = { > + .name = "cv1800-pwm", > + .of_match_table = cv1800_pwm_dt_ids, > + }, > +}; > +module_platform_driver(cv1800_pwm_driver); > + > +MODULE_AUTHOR("Jingbao Qiu"); > +MODULE_DESCRIPTION("Sophgo cv1800 PWM Driver"); > +MODULE_LICENSE("GPL"); > -- > 2.25.1 > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-riscv