zephyr/soc/arm/st_stm32/stm32h7/soc_m4.c

93 lines
2.1 KiB
C

/*
* Copyright (c) 2019 Linaro Limited
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief System/hardware module for STM32H7 CM4 processor
*/
#include <kernel.h>
#include <device.h>
#include <init.h>
#include <soc.h>
#include <arch/cpu.h>
#include <arch/arm/cortex_m/cmsis.h>
#if defined(CONFIG_STM32H7_BOOT_CM4_CM7)
void stm32h7_m4_boot_stop(void)
{
/*
* Domain D2 goes to STOP mode (Cortex-M4 in deep-sleep) waiting for
* Cortex-M7 to perform system initialization (system clock config,
* external memory configuration.. )
*/
/* Clear pending events if any */
__SEV();
__WFE();
/* Select the domain Power Down DeepSleep */
LL_PWR_SetRegulModeDS(LL_PWR_REGU_DSMODE_MAIN);
/* Keep DSTOP mode when D2 domain enters Deepsleep */
LL_PWR_CPU_SetD2PowerMode(LL_PWR_CPU_MODE_D2STOP);
LL_PWR_CPU2_SetD2PowerMode(LL_PWR_CPU2_MODE_D2STOP);
/* Set SLEEPDEEP bit of Cortex System Control Register */
LL_LPM_EnableDeepSleep();
/* Ensure that all instructions done before entering STOP mode */
__DSB();
__ISB();
/* Request Wait For Event */
__WFE();
/* Reset SLEEPDEEP bit of Cortex System Control Register,
* the following LL API Clear SLEEPDEEP bit of Cortex
* System Control Register
*/
LL_LPM_EnableSleep();
}
#endif /* CONFIG_STM32H7_BOOT_CM4_CM7 */
/**
* @brief Perform basic hardware initialization at boot.
*
* This needs to be run from the very beginning.
* So the init priority has to be 0 (zero).
*
* @return 0
*/
static int stm32h7_m4_init(struct device *arg)
{
u32_t key;
key = irq_lock();
/* Install default handler that simply resets the CPU
* if configured in the kernel, NOP otherwise
*/
NMI_INIT();
irq_unlock(key);
/*HW semaphore Clock enable*/
LL_AHB4_GRP1_EnableClock(LL_AHB4_GRP1_PERIPH_HSEM);
#if defined(CONFIG_STM32H7_BOOT_CM4_CM7)
/* Activate HSEM notification for Cortex-M4*/
LL_HSEM_EnableIT_C2IER(HSEM, LL_HSEM_MASK_0);
/* Boot and enter stop mode */
stm32h7_m4_boot_stop();
/* Clear HSEM flag */
LL_HSEM_ClearFlag_C2ICR(HSEM, LL_HSEM_MASK_0);
#endif /* CONFIG_STM32H7_BOOT_CM4_CM7 */
return 0;
}
SYS_INIT(stm32h7_m4_init, PRE_KERNEL_1, 0);