include/zephyr/dt-bindings/clock/stm32l0_clock.h

/*
 * Copyright (c) 2022 Linaro Limited
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef ZEPHYR_INCLUDE_DT_BINDINGS_CLOCK_STM32L0_CLOCK_H_
#define ZEPHYR_INCLUDE_DT_BINDINGS_CLOCK_STM32L0_CLOCK_H_

/** Bus gatting clocks */
#define STM32_CLOCK_BUS_IOP     0x02c
#define STM32_CLOCK_BUS_AHB1    0x030
#define STM32_CLOCK_BUS_APB2    0x034
#define STM32_CLOCK_BUS_APB1    0x038

#define STM32_PERIPH_BUS_MIN	STM32_CLOCK_BUS_IOP
#define STM32_PERIPH_BUS_MAX	STM32_CLOCK_BUS_APB1

/** Peripheral clock sources */
/* RM0367, §7.3.20 Clock configuration register (RCC_CCIPR) */

/** Fixed clocks  */
#define STM32_SRC_HSE		0x001
#define STM32_SRC_LSE		0x002
#define STM32_SRC_LSI		0x003
#define STM32_SRC_HSI		0x004
/** System clock */
#define STM32_SRC_SYSCLK	0x005
/** Bus clock */
#define STM32_SRC_PCLK		0x006

/**
 * @brief STM32 clock configuration bit field.
 *
 * - reg   (1/2/3)         [ 0 : 7 ]
 * - shift (0..31)         [ 8 : 12 ]
 * - mask  (0x1, 0x3, 0x7) [ 13 : 15 ]
 * - val   (0..7)          [ 16 : 18 ]
 *
 * @param reg RCC_CCIPRx register offset
 * @param shift Position within RCC_CCIPRx.
 * @param mask Mask for the RCC_CCIPRx field.
 * @param val Clock value (0, 1, ... 7).
 */

#define STM32_CLOCK_REG_MASK    0xFFU
#define STM32_CLOCK_REG_SHIFT   0U
#define STM32_CLOCK_SHIFT_MASK  0x1FU
#define STM32_CLOCK_SHIFT_SHIFT 8U
#define STM32_CLOCK_MASK_MASK   0x7U
#define STM32_CLOCK_MASK_SHIFT  13U
#define STM32_CLOCK_VAL_MASK    0x7U
#define STM32_CLOCK_VAL_SHIFT   16U

#define STM32_CLOCK(val, mask, shift, reg)					\
	((((reg) & STM32_CLOCK_REG_MASK) << STM32_CLOCK_REG_SHIFT) |		\
	 (((shift) & STM32_CLOCK_SHIFT_MASK) << STM32_CLOCK_SHIFT_SHIFT) |	\
	 (((mask) & STM32_CLOCK_MASK_MASK) << STM32_CLOCK_MASK_SHIFT) |		\
	 (((val) & STM32_CLOCK_VAL_MASK) << STM32_CLOCK_VAL_SHIFT))

/** @brief RCC_CCIPR register offset */
#define CCIPR_REG		0x4C

/** @brief Device clk sources selection helpers */
/** CCIPR devices */
#define USART1_SEL(val)		STM32_CLOCK(val, 3, 0, CCIPR_REG)
#define USART2_SEL(val)		STM32_CLOCK(val, 3, 2, CCIPR_REG)
#define LPUART1_SEL(val)	STM32_CLOCK(val, 3, 10, CCIPR_REG)
#define I2C1_SEL(val)		STM32_CLOCK(val, 3, 12, CCIPR_REG)
#define I2C3_SEL(val)		STM32_CLOCK(val, 3, 16, CCIPR_REG)
#define LPTIM1_SEL(val)		STM32_CLOCK(val, 3, 18, CCIPR_REG)
#define HSI48_SEL(val)		STM32_CLOCK(val, 1, 26, CCIPR_REG)

#endif /* ZEPHYR_INCLUDE_DT_BINDINGS_CLOCK_STM32L0_CLOCK_H_ */