u-boot/arch/arm/mach-owl/soc.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Actions Semi Owl SoCs platform support.
 *
 * Copyright (C) 2018 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
 */

#include <cpu_func.h>
#include <init.h>
#include <asm/cache.h>
#include <asm/global_data.h>
#include <linux/arm-smccc.h>
#include <linux/psci.h>
#include <common.h>
#include <asm/io.h>
#include <asm/mach-types.h>
#include <asm/psci.h>

#define DMM_INTERLEAVE_PER_CH_CFG	0xe0290028

DECLARE_GLOBAL_DATA_PTR;

unsigned int owl_get_ddrcap(void)
{
	unsigned int val, cap;

	/* ddr capacity register initialized by ddr driver
	 * in early bootloader
	 */
#if defined(CONFIG_MACH_S700)
	val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0x7;
	cap =  (val + 1) * 256;
#elif defined(CONFIG_MACH_S900)
	val = (readl(DMM_INTERLEAVE_PER_CH_CFG) >> 8) & 0xf;
	cap =  64 * (1 << val);
#endif

	return cap;
}

/*
 * dram_init - sets uboots idea of sdram size
 */
int dram_init(void)
{
	gd->ram_size = owl_get_ddrcap() * 1024 * 1024;
	return 0;
}

/* This is called after dram_init() so use get_ram_size result */
int dram_init_banksize(void)
{
	gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE;
	gd->bd->bi_dram[0].size = gd->ram_size;

	return 0;
}

static void show_psci_version(void)
{
	struct arm_smccc_res res;

	arm_smccc_smc(ARM_PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0, 0, 0, 0, 0, &res);

	printf("PSCI:  v%ld.%ld\n",
		PSCI_VERSION_MAJOR(res.a0),
		PSCI_VERSION_MINOR(res.a0));
}

int board_init(void)
{
	show_psci_version();

	return 0;
}

void reset_cpu(void)
{
	psci_system_reset();
}