于 2017年9月19日 GMT+08:00 下午4:51:32, Andre Przywara <andre.przyw...@arm.com> 写到: >Hi, > >On 19/09/17 06:06, Vasily Khoruzhick wrote: >> This commit adds basic support for PWM found on Allwinner A64 and H3 > >Mmh, can you explain (for instance in a 0/3 email) what this is used >for? My understanding is that PWM0 (which is what you hard code here) >is >only exposed on PD22, which is also used for the MDC line to the >Ethernet PHY. All boards I heard of have Ethernet, so PWM0 is not >usable >there. >So is this for a special board?
Backlight for Pinebook. > >> >> Signed-off-by: Vasily Khoruzhick <anars...@gmail.com> >> --- >> arch/arm/include/asm/arch-sunxi/gpio.h | 1 + >> arch/arm/include/asm/arch-sunxi/pwm.h | 12 +++ >> arch/arm/mach-sunxi/board.c | 11 +++ >> drivers/pwm/Kconfig | 7 ++ >> drivers/pwm/Makefile | 1 + >> drivers/pwm/sunxi_pwm.c | 174 >+++++++++++++++++++++++++++++++++ >> 6 files changed, 206 insertions(+) >> create mode 100644 drivers/pwm/sunxi_pwm.c >> >> diff --git a/arch/arm/include/asm/arch-sunxi/gpio.h >b/arch/arm/include/asm/arch-sunxi/gpio.h >> index 24f85206c8..7265d18099 100644 >> --- a/arch/arm/include/asm/arch-sunxi/gpio.h >> +++ b/arch/arm/include/asm/arch-sunxi/gpio.h >> @@ -173,6 +173,7 @@ enum sunxi_gpio_number { >> #define SUN8I_GPD_SDC1 3 >> #define SUNXI_GPD_LCD0 2 >> #define SUNXI_GPD_LVDS0 3 >> +#define SUNXI_GPD_PWM 2 >> >> #define SUN5I_GPE_SDC2 3 >> #define SUN8I_GPE_TWI2 3 >> diff --git a/arch/arm/include/asm/arch-sunxi/pwm.h >b/arch/arm/include/asm/arch-sunxi/pwm.h >> index 5884b5dbe7..673e0eb7b5 100644 >> --- a/arch/arm/include/asm/arch-sunxi/pwm.h >> +++ b/arch/arm/include/asm/arch-sunxi/pwm.h >> @@ -11,8 +11,15 @@ >> #define SUNXI_PWM_CH0_PERIOD (SUNXI_PWM_BASE + 4) >> >> #define SUNXI_PWM_CTRL_PRESCALE0(x) ((x) & 0xf) >> +#define SUNXI_PWM_CTRL_PRESCALE0_MASK (0xf) >> #define SUNXI_PWM_CTRL_ENABLE0 (0x5 << 4) >> #define SUNXI_PWM_CTRL_POLARITY0(x) ((x) << 5) >> +#define SUNXI_PWM_CTRL_POLARITY0_MASK (1 << 5) >> +#define SUNXI_PWM_CTRL_CLK_GATE (1 << 6) >> + >> +#define SUNXI_PWM_CH0_PERIOD_MAX (0xffff) >> +#define SUNXI_PWM_CH0_PERIOD_PRD(x) ((x & 0xffff) << 16) >> +#define SUNXI_PWM_CH0_PERIOD_DUTY(x) ((x) & 0xffff) >> >> #define SUNXI_PWM_PERIOD_80PCT 0x04af03c0 >> >> @@ -31,4 +38,9 @@ >> #define SUNXI_PWM_MUX SUN8I_GPH_PWM >> #endif >> >> +struct sunxi_pwm { >> + u32 ctrl; >> + u32 ch0_period; >> +}; >> + >> #endif >> diff --git a/arch/arm/mach-sunxi/board.c >b/arch/arm/mach-sunxi/board.c >> index 65b1ebd837..a85f973a46 100644 >> --- a/arch/arm/mach-sunxi/board.c >> +++ b/arch/arm/mach-sunxi/board.c >> @@ -141,6 +141,16 @@ static int gpio_init(void) >> return 0; >> } >> >> +static int pwm_init(void) >> +{ >> +#ifdef CONFIG_PWM_SUNXI >> +#ifdef CONFIG_MACH_SUN50I >> + sunxi_gpio_set_cfgpin(SUNXI_GPD(22), SUNXI_GPD_PWM); > >So this would probably kill Ethernet. >At the very least this should be somehow protected against this clash. >And I wonder if this should move into the PWM driver, for instance into >the .enable function. > >Cheers, >Andre. > >> +#endif >> +#endif >> + return 0; >> +} >> + >> #if defined(CONFIG_SPL_BOARD_LOAD_IMAGE) && >defined(CONFIG_SPL_BUILD) >> static int spl_board_load_image(struct spl_image_info *spl_image, >> struct spl_boot_device *bootdev) >> @@ -204,6 +214,7 @@ void s_init(void) >> clock_init(); >> timer_init(); >> gpio_init(); >> + pwm_init(); >> #ifndef CONFIG_DM_I2C >> i2c_init_board(); >> #endif >> diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig >> index e827558052..67e3f355e7 100644 >> --- a/drivers/pwm/Kconfig >> +++ b/drivers/pwm/Kconfig >> @@ -43,3 +43,10 @@ config PWM_TEGRA >> four channels with a programmable period and duty cycle. Only a >> 32KHz clock is supported by the driver but the duty cycle is >> configurable. >> + >> +config PWM_SUNXI >> + bool "Enable support for the Allwinner Sunxi PWM" >> + depends on DM_PWM >> + help >> + This PWM is found on A64 and other Allwinner SoCs. It supports a >> + programmable period and duty cycle. A 32-bit counter is used. >> diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile >> index 29d59916cb..1a8f8a58bc 100644 >> --- a/drivers/pwm/Makefile >> +++ b/drivers/pwm/Makefile >> @@ -17,3 +17,4 @@ obj-$(CONFIG_PWM_IMX) += pwm-imx.o >> pwm-imx-util.o >> obj-$(CONFIG_PWM_ROCKCHIP) += rk_pwm.o >> obj-$(CONFIG_PWM_SANDBOX) += sandbox_pwm.o >> obj-$(CONFIG_PWM_TEGRA) += tegra_pwm.o >> +obj-$(CONFIG_PWM_SUNXI) += sunxi_pwm.o >> diff --git a/drivers/pwm/sunxi_pwm.c b/drivers/pwm/sunxi_pwm.c >> new file mode 100644 >> index 0000000000..3e6d69fa1c >> --- /dev/null >> +++ b/drivers/pwm/sunxi_pwm.c >> @@ -0,0 +1,174 @@ >> +/* >> + * Copyright (c) 2017 Vasily Khoruzhick <anars...@gmail.com> >> + * >> + * SPDX-License-Identifier: GPL-2.0+ >> + */ >> + >> +#include <common.h> >> +#include <div64.h> >> +#include <dm.h> >> +#include <pwm.h> >> +#include <regmap.h> >> +#include <syscon.h> >> +#include <asm/io.h> >> +#include <asm/arch/pwm.h> >> +#include <power/regulator.h> >> + >> +DECLARE_GLOBAL_DATA_PTR; >> + >> +struct sunxi_pwm_priv { >> + struct sunxi_pwm *regs; >> + ulong freq; >> + bool invert; >> + uint32_t prescaler; >> +}; >> + >> +static const uint32_t prescaler_table[] = { >> + 120, /* 0000 */ >> + 180, /* 0001 */ >> + 240, /* 0010 */ >> + 360, /* 0011 */ >> + 480, /* 0100 */ >> + 0, /* 0101 */ >> + 0, /* 0110 */ >> + 0, /* 0111 */ >> + 12000, /* 1000 */ >> + 24000, /* 1001 */ >> + 36000, /* 1010 */ >> + 48000, /* 1011 */ >> + 72000, /* 1100 */ >> + 0, /* 1101 */ >> + 0, /* 1110 */ >> + 1, /* 1111 */ >> +}; >> + >> +static const uint64_t nsecs_per_sec = 1000000000L; >> + >> +static int sunxi_pwm_set_invert(struct udevice *dev, uint channel, >bool polarity) >> +{ >> + struct sunxi_pwm_priv *priv = dev_get_priv(dev); >> + >> + debug("%s: polarity=%u\n", __func__, polarity); >> + priv->invert = polarity; >> + >> + return 0; >> +} >> + >> +static int sunxi_pwm_set_config(struct udevice *dev, uint channel, >uint period_ns, >> + uint duty_ns) >> +{ >> + struct sunxi_pwm_priv *priv = dev_get_priv(dev); >> + struct sunxi_pwm *regs = priv->regs; >> + int prescaler; >> + u32 v, period, duty; >> + uint64_t div = 0, pval = 0, scaled_freq = 0; >> + >> + debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, >duty_ns); >> + >> + for (prescaler = 0; prescaler < SUNXI_PWM_CTRL_PRESCALE0_MASK; >prescaler++) { >> + if (!prescaler_table[prescaler]) >> + continue; >> + div = priv->freq; >> + pval = prescaler_table[prescaler]; >> + scaled_freq = lldiv(div, pval); >> + div = scaled_freq * period_ns; >> + div = lldiv(div, nsecs_per_sec); >> + if (div - 1 <= SUNXI_PWM_CH0_PERIOD_MAX) >> + break; >> + } >> + >> + if (div - 1 > SUNXI_PWM_CH0_PERIOD_MAX) { >> + debug("%s: failed to find prescaler value\n", __func__); >> + return -EINVAL; >> + } >> + >> + period = div; >> + div = scaled_freq * duty_ns; >> + div = lldiv(div, nsecs_per_sec); >> + duty = div; >> + >> + if (priv->prescaler != prescaler) { >> + /* Mask clock to update prescaler */ >> + v = readl(®s->ctrl); >> + v &= ~SUNXI_PWM_CTRL_CLK_GATE; >> + writel(v, ®s->ctrl); >> + v &= ~SUNXI_PWM_CTRL_PRESCALE0_MASK; >> + v |= (priv->prescaler & SUNXI_PWM_CTRL_PRESCALE0_MASK); >> + writel(v, ®s->ctrl); >> + v |= SUNXI_PWM_CTRL_CLK_GATE; >> + writel(v, ®s->ctrl); >> + priv->prescaler = prescaler; >> + } >> + >> + writel(SUNXI_PWM_CH0_PERIOD_PRD(period) | >> + SUNXI_PWM_CH0_PERIOD_DUTY(duty), ®s->ch0_period); >> + >> + debug("%s: prescaler: %d, period: %d, duty: %d\n", __func__, >priv->prescaler, >> + period, duty); >> + >> + return 0; >> +} >> + >> +static int sunxi_pwm_set_enable(struct udevice *dev, uint channel, >bool enable) >> +{ >> + struct sunxi_pwm_priv *priv = dev_get_priv(dev); >> + struct sunxi_pwm *regs = priv->regs; >> + uint32_t v; >> + >> + debug("%s: Enable '%s'\n", __func__, dev->name); >> + >> + v = readl(®s->ctrl); >> + if (!enable) { >> + v &= ~SUNXI_PWM_CTRL_ENABLE0; >> + writel(v, ®s->ctrl); >> + return 0; >> + } >> + >> + v &= ~SUNXI_PWM_CTRL_POLARITY0_MASK; >> + v |= priv->invert ? SUNXI_PWM_CTRL_POLARITY0(0) : >> + SUNXI_PWM_CTRL_POLARITY0(1); >> + v |= SUNXI_PWM_CTRL_ENABLE0; >> + writel(v, ®s->ctrl); >> + >> + return 0; >> +} >> + >> +static int sunxi_pwm_ofdata_to_platdata(struct udevice *dev) >> +{ >> + struct sunxi_pwm_priv *priv = dev_get_priv(dev); >> + >> + priv->regs = (struct sunxi_pwm *)devfdt_get_addr(dev); >> + >> + return 0; >> +} >> + >> +static int sunxi_pwm_probe(struct udevice *dev) >> +{ >> + struct sunxi_pwm_priv *priv = dev_get_priv(dev); >> + >> + priv->freq = 24000000; >> + >> + return 0; >> +} >> + >> +static const struct pwm_ops sunxi_pwm_ops = { >> + .set_invert = sunxi_pwm_set_invert, >> + .set_config = sunxi_pwm_set_config, >> + .set_enable = sunxi_pwm_set_enable, >> +}; >> + >> +static const struct udevice_id sunxi_pwm_ids[] = { >> + { .compatible = "allwinner,sun8i-h3-pwm" }, >> + { .compatible = "allwinner,sun50i-a64-pwm" }, >> + { } >> +}; >> + >> +U_BOOT_DRIVER(sunxi_pwm) = { >> + .name = "sunxi_pwm", >> + .id = UCLASS_PWM, >> + .of_match = sunxi_pwm_ids, >> + .ops = &sunxi_pwm_ops, >> + .ofdata_to_platdata = sunxi_pwm_ofdata_to_platdata, >> + .probe = sunxi_pwm_probe, >> + .priv_auto_alloc_size = sizeof(struct sunxi_pwm_priv), >> +}; >> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot