U-Boot

// SPDX-License-Identifier: GPL-2.0+

#include <asm/secure.h>
#include <asm/psci.h>
#include <asm/types.h>
#include <asm/io.h>
#include <asm/system.h>

#define GPIO2_GPDIR	0x2310000
#define GPIO2_GPDAT	0x2310008
#define RSTCR		0x1e60000
#define RESET_REQ	BIT(1)

u32 __secure psci_version(void)
{
	return ARM_PSCI_VER_0_2;
}

void __secure psci_system_reset(void)
{
	writel(RESET_REQ, RSTCR);

	while (1)
		wfi();
}

void __secure psci_system_off(void)
{
	int i;

	writel(0x02000000, GPIO2_GPDIR);
	writel(0, GPIO2_GPDAT);

	/* make sure the management controller has sampled the input */
	for (i = 0; i < (1 << 11); i++)
		asm("nop");

	writel(RESET_REQ, RSTCR);

	while (1)
		wfi();
}