diff options
| -rw-r--r-- | configs/stm32mp15_basic_defconfig | 2 | ||||
| -rw-r--r-- | configs/stm32mp15_optee_defconfig | 2 | ||||
| -rw-r--r-- | configs/stm32mp15_trusted_defconfig | 2 | ||||
| -rw-r--r-- | drivers/rtc/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/stm32_rtc.c | 323 |
6 files changed, 336 insertions, 0 deletions
diff --git a/configs/stm32mp15_basic_defconfig b/configs/stm32mp15_basic_defconfig index 9170e8e..27b8525 100644 --- a/configs/stm32mp15_basic_defconfig +++ b/configs/stm32mp15_basic_defconfig @@ -102,6 +102,8 @@ CONFIG_DM_REGULATOR_GPIO=y CONFIG_DM_REGULATOR_STM32_VREFBUF=y CONFIG_DM_REGULATOR_STPMIC1=y CONFIG_REMOTEPROC_STM32_COPRO=y +CONFIG_DM_RTC=y +CONFIG_RTC_STM32=y CONFIG_SERIAL_RX_BUFFER=y CONFIG_STM32_SERIAL=y CONFIG_SPI=y diff --git a/configs/stm32mp15_optee_defconfig b/configs/stm32mp15_optee_defconfig index 6d60af2..0565e5e 100644 --- a/configs/stm32mp15_optee_defconfig +++ b/configs/stm32mp15_optee_defconfig @@ -89,6 +89,8 @@ CONFIG_DM_REGULATOR_GPIO=y CONFIG_DM_REGULATOR_STM32_VREFBUF=y CONFIG_DM_REGULATOR_STPMIC1=y CONFIG_REMOTEPROC_STM32_COPRO=y +CONFIG_DM_RTC=y +CONFIG_RTC_STM32=y CONFIG_SERIAL_RX_BUFFER=y CONFIG_STM32_SERIAL=y CONFIG_SPI=y diff --git a/configs/stm32mp15_trusted_defconfig b/configs/stm32mp15_trusted_defconfig index 35ca696..844cbcd 100644 --- a/configs/stm32mp15_trusted_defconfig +++ b/configs/stm32mp15_trusted_defconfig @@ -88,6 +88,8 @@ CONFIG_DM_REGULATOR_GPIO=y CONFIG_DM_REGULATOR_STM32_VREFBUF=y CONFIG_DM_REGULATOR_STPMIC1=y CONFIG_REMOTEPROC_STM32_COPRO=y +CONFIG_DM_RTC=y +CONFIG_RTC_STM32=y CONFIG_SERIAL_RX_BUFFER=y CONFIG_STM32_SERIAL=y CONFIG_SPI=y diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 532e94d..0b58a18 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -120,4 +120,10 @@ config RTC_M41T62 Enable driver for ST's M41T62 compatible RTC devices (like RV-4162). It is a serial (I2C) real-time clock (RTC) with alarm. +config RTC_STM32 + bool "Enable STM32 RTC driver" + depends on DM_RTC + help + Enable STM32 RTC driver. This driver supports the rtc that is present + on some STM32 SoCs. endmenu diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 915adb8..f97a669 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -51,5 +51,6 @@ obj-$(CONFIG_RTC_RX8025) += rx8025.o obj-$(CONFIG_RTC_RX8010SJ) += rx8010sj.o obj-$(CONFIG_RTC_S3C24X0) += s3c24x0_rtc.o obj-$(CONFIG_RTC_S35392A) += s35392a.o +obj-$(CONFIG_RTC_STM32) += stm32_rtc.o obj-$(CONFIG_SANDBOX) += sandbox_rtc.o obj-$(CONFIG_RTC_X1205) += x1205.o diff --git a/drivers/rtc/stm32_rtc.c b/drivers/rtc/stm32_rtc.c new file mode 100644 index 0000000..abd3390 --- /dev/null +++ b/drivers/rtc/stm32_rtc.c @@ -0,0 +1,323 @@ +// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause +/* + * Copyright (C) 2019, STMicroelectronics - All Rights Reserved + */ +#include <common.h> +#include <clk.h> +#include <dm.h> +#include <rtc.h> +#include <asm/io.h> +#include <linux/iopoll.h> + +#define STM32_RTC_TR 0x00 +#define STM32_RTC_DR 0x04 +#define STM32_RTC_ISR 0x0C +#define STM32_RTC_PRER 0x10 +#define STM32_RTC_CR 0x18 +#define STM32_RTC_WPR 0x24 + +/* STM32_RTC_TR bit fields */ +#define STM32_RTC_SEC_SHIFT 0 +#define STM32_RTC_SEC GENMASK(6, 0) +#define STM32_RTC_MIN_SHIFT 8 +#define STM32_RTC_MIN GENMASK(14, 8) +#define STM32_RTC_HOUR_SHIFT 16 +#define STM32_RTC_HOUR GENMASK(21, 16) + +/* STM32_RTC_DR bit fields */ +#define STM32_RTC_DATE_SHIFT 0 +#define STM32_RTC_DATE GENMASK(5, 0) +#define STM32_RTC_MONTH_SHIFT 8 +#define STM32_RTC_MONTH GENMASK(12, 8) +#define STM32_RTC_WDAY_SHIFT 13 +#define STM32_RTC_WDAY GENMASK(15, 13) +#define STM32_RTC_YEAR_SHIFT 16 +#define STM32_RTC_YEAR GENMASK(23, 16) + +/* STM32_RTC_CR bit fields */ +#define STM32_RTC_CR_FMT BIT(6) + +/* STM32_RTC_ISR/STM32_RTC_ICSR bit fields */ +#define STM32_RTC_ISR_INITS BIT(4) +#define STM32_RTC_ISR_RSF BIT(5) +#define STM32_RTC_ISR_INITF BIT(6) +#define STM32_RTC_ISR_INIT BIT(7) + +/* STM32_RTC_PRER bit fields */ +#define STM32_RTC_PRER_PRED_S_SHIFT 0 +#define STM32_RTC_PRER_PRED_S GENMASK(14, 0) +#define STM32_RTC_PRER_PRED_A_SHIFT 16 +#define STM32_RTC_PRER_PRED_A GENMASK(22, 16) + +/* STM32_RTC_WPR key constants */ +#define RTC_WPR_1ST_KEY 0xCA +#define RTC_WPR_2ND_KEY 0x53 +#define RTC_WPR_WRONG_KEY 0xFF + +struct stm32_rtc_priv { + fdt_addr_t base; +}; + +static int stm32_rtc_get(struct udevice *dev, struct rtc_time *tm) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + u32 tr, dr; + + tr = readl(priv->base + STM32_RTC_TR); + dr = readl(priv->base + STM32_RTC_DR); + + tm->tm_sec = bcd2bin((tr & STM32_RTC_SEC) >> STM32_RTC_SEC_SHIFT); + tm->tm_min = bcd2bin((tr & STM32_RTC_MIN) >> STM32_RTC_MIN_SHIFT); + tm->tm_hour = bcd2bin((tr & STM32_RTC_HOUR) >> STM32_RTC_HOUR_SHIFT); + + tm->tm_mday = bcd2bin((dr & STM32_RTC_DATE) >> STM32_RTC_DATE_SHIFT); + tm->tm_mon = bcd2bin((dr & STM32_RTC_MONTH) >> STM32_RTC_MONTH_SHIFT); + tm->tm_year = bcd2bin((dr & STM32_RTC_YEAR) >> STM32_RTC_YEAR_SHIFT); + tm->tm_wday = bcd2bin((dr & STM32_RTC_WDAY) >> STM32_RTC_WDAY_SHIFT); + tm->tm_yday = 0; + tm->tm_isdst = 0; + + dev_dbg(dev, "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, + tm->tm_hour, tm->tm_min, tm->tm_sec); + + return 0; +} + +static void stm32_rtc_unlock(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + + writel(RTC_WPR_1ST_KEY, priv->base + STM32_RTC_WPR); + writel(RTC_WPR_2ND_KEY, priv->base + STM32_RTC_WPR); +} + +static void stm32_rtc_lock(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + + writel(RTC_WPR_WRONG_KEY, priv->base + STM32_RTC_WPR); +} + +static int stm32_rtc_enter_init_mode(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + u32 isr = readl(priv->base + STM32_RTC_ISR); + + if (!(isr & STM32_RTC_ISR_INITF)) { + isr |= STM32_RTC_ISR_INIT; + writel(isr, priv->base + STM32_RTC_ISR); + + return readl_poll_timeout(priv->base + STM32_RTC_ISR, + isr, + (isr & STM32_RTC_ISR_INITF), + 100000); + } + + return 0; +} + +static int stm32_rtc_wait_sync(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + u32 isr = readl(priv->base + STM32_RTC_ISR); + + isr &= ~STM32_RTC_ISR_RSF; + writel(isr, priv->base + STM32_RTC_ISR); + + /* + * Wait for RSF to be set to ensure the calendar registers are + * synchronised, it takes around 2 rtc_ck clock cycles + */ + return readl_poll_timeout(priv->base + STM32_RTC_ISR, + isr, (isr & STM32_RTC_ISR_RSF), + 100000); +} + +static void stm32_rtc_exit_init_mode(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + u32 isr = readl(priv->base + STM32_RTC_ISR); + + isr &= ~STM32_RTC_ISR_INIT; + writel(isr, priv->base + STM32_RTC_ISR); +} + +static int stm32_rtc_set_time(struct udevice *dev, u32 time, u32 date) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + int ret; + + stm32_rtc_unlock(dev); + + ret = stm32_rtc_enter_init_mode(dev); + if (ret) + goto lock; + + writel(time, priv->base + STM32_RTC_TR); + writel(date, priv->base + STM32_RTC_DR); + + stm32_rtc_exit_init_mode(dev); + + ret = stm32_rtc_wait_sync(dev); + +lock: + stm32_rtc_lock(dev); + return ret; +} + +static int stm32_rtc_set(struct udevice *dev, const struct rtc_time *tm) +{ + u32 t, d; + + dev_dbg(dev, "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, + tm->tm_hour, tm->tm_min, tm->tm_sec); + + /* Time in BCD format */ + t = (bin2bcd(tm->tm_sec) << STM32_RTC_SEC_SHIFT) & STM32_RTC_SEC; + t |= (bin2bcd(tm->tm_min) << STM32_RTC_MIN_SHIFT) & STM32_RTC_MIN; + t |= (bin2bcd(tm->tm_hour) << STM32_RTC_HOUR_SHIFT) & STM32_RTC_HOUR; + + /* Date in BCD format */ + d = (bin2bcd(tm->tm_mday) << STM32_RTC_DATE_SHIFT) & STM32_RTC_DATE; + d |= (bin2bcd(tm->tm_mon) << STM32_RTC_MONTH_SHIFT) & STM32_RTC_MONTH; + d |= (bin2bcd(tm->tm_year) << STM32_RTC_YEAR_SHIFT) & STM32_RTC_YEAR; + d |= (bin2bcd(tm->tm_wday) << STM32_RTC_WDAY_SHIFT) & STM32_RTC_WDAY; + + return stm32_rtc_set_time(dev, t, d); +} + +static int stm32_rtc_reset(struct udevice *dev) +{ + dev_dbg(dev, "Reset DATE\n"); + + return stm32_rtc_set_time(dev, 0, 0); +} + +static int stm32_rtc_init(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + unsigned int prer, pred_a, pred_s, pred_a_max, pred_s_max, cr; + unsigned int rate; + struct clk clk; + int ret; + u32 isr = readl(priv->base + STM32_RTC_ISR); + + if (isr & STM32_RTC_ISR_INITS) + return 0; + + ret = clk_get_by_index(dev, 1, &clk); + if (ret) + return ret; + + ret = clk_enable(&clk); + if (ret) { + clk_free(&clk); + return ret; + } + + rate = clk_get_rate(&clk); + + /* Find prediv_a and prediv_s to obtain the 1Hz calendar clock */ + pred_a_max = STM32_RTC_PRER_PRED_A >> STM32_RTC_PRER_PRED_A_SHIFT; + pred_s_max = STM32_RTC_PRER_PRED_S >> STM32_RTC_PRER_PRED_S_SHIFT; + + for (pred_a = pred_a_max; pred_a + 1 > 0; pred_a--) { + pred_s = (rate / (pred_a + 1)) - 1; + + if (((pred_s + 1) * (pred_a + 1)) == rate) + break; + } + + /* + * Can't find a 1Hz, so give priority to RTC power consumption + * by choosing the higher possible value for prediv_a + */ + if (pred_s > pred_s_max || pred_a > pred_a_max) { + pred_a = pred_a_max; + pred_s = (rate / (pred_a + 1)) - 1; + } + + stm32_rtc_unlock(dev); + + ret = stm32_rtc_enter_init_mode(dev); + if (ret) { + dev_err(dev, + "Can't enter in init mode. Prescaler config failed.\n"); + goto unlock; + } + + prer = (pred_s << STM32_RTC_PRER_PRED_S_SHIFT) & STM32_RTC_PRER_PRED_S; + prer |= (pred_a << STM32_RTC_PRER_PRED_A_SHIFT) & STM32_RTC_PRER_PRED_A; + writel(prer, priv->base + STM32_RTC_PRER); + + /* Force 24h time format */ + cr = readl(priv->base + STM32_RTC_CR); + cr &= ~STM32_RTC_CR_FMT; + writel(cr, priv->base + STM32_RTC_CR); + + stm32_rtc_exit_init_mode(dev); + + ret = stm32_rtc_wait_sync(dev); + +unlock: + stm32_rtc_lock(dev); + + if (ret) { + clk_disable(&clk); + clk_free(&clk); + } + + return ret; +} + +static int stm32_rtc_probe(struct udevice *dev) +{ + struct stm32_rtc_priv *priv = dev_get_priv(dev); + struct clk clk; + int ret; + + priv->base = dev_read_addr(dev); + if (priv->base == FDT_ADDR_T_NONE) + return -EINVAL; + + ret = clk_get_by_index(dev, 0, &clk); + if (ret) + return ret; + + ret = clk_enable(&clk); + if (ret) { + clk_free(&clk); + return ret; + } + + ret = stm32_rtc_init(dev); + + if (ret) { + clk_disable(&clk); + clk_free(&clk); + } + + return ret; +} + +static const struct rtc_ops stm32_rtc_ops = { + .get = stm32_rtc_get, + .set = stm32_rtc_set, + .reset = stm32_rtc_reset, +}; + +static const struct udevice_id stm32_rtc_ids[] = { + { .compatible = "st,stm32mp1-rtc" }, + { } +}; + +U_BOOT_DRIVER(rtc_stm32) = { + .name = "rtc-stm32", + .id = UCLASS_RTC, + .probe = stm32_rtc_probe, + .of_match = stm32_rtc_ids, + .ops = &stm32_rtc_ops, + .priv_auto_alloc_size = sizeof(struct stm32_rtc_priv), +}; |