stm32mp1: split code between common and private parts

Some parts of code could be shared with platform derivatives,
or new platforms.
A new folder plat/st/common is created to put common parts.

stm32mp_common.h is a common API aggregate.

Remove some casts where applicable.
Fix some types where applicable.
Remove also some platform includes that are already in stm32mp1_def.h.

Change-Id: I46d763c8d9e15732d1ee7383207fd58206d7f583
Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
diff --git a/plat/st/common/bl2_io_storage.c b/plat/st/common/bl2_io_storage.c
new file mode 100644
index 0000000..18342aa
--- /dev/null
+++ b/plat/st/common/bl2_io_storage.c
@@ -0,0 +1,310 @@
+/*
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <string.h>
+
+#include <platform_def.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <drivers/io/io_block.h>
+#include <drivers/io/io_driver.h>
+#include <drivers/io/io_dummy.h>
+#include <drivers/io/io_storage.h>
+#include <drivers/mmc.h>
+#include <drivers/partition/partition.h>
+#include <drivers/st/io_mmc.h>
+#include <drivers/st/io_stm32image.h>
+#include <drivers/st/stm32_sdmmc2.h>
+#include <drivers/st/stm32mp1_rcc.h>
+#include <lib/mmio.h>
+#include <lib/utils.h>
+#include <plat/common/platform.h>
+
+/* IO devices */
+static const io_dev_connector_t *dummy_dev_con;
+static uintptr_t dummy_dev_handle;
+static uintptr_t dummy_dev_spec;
+
+static uintptr_t image_dev_handle;
+
+static io_block_spec_t gpt_block_spec = {
+	.offset = 0,
+	.length = 34 * MMC_BLOCK_SIZE, /* Size of GPT table */
+};
+
+static uint32_t block_buffer[MMC_BLOCK_SIZE] __aligned(MMC_BLOCK_SIZE);
+
+static const io_block_dev_spec_t mmc_block_dev_spec = {
+	/* It's used as temp buffer in block driver */
+	.buffer = {
+		.offset = (size_t)&block_buffer,
+		.length = MMC_BLOCK_SIZE,
+	},
+	.ops = {
+		.read = mmc_read_blocks,
+		.write = NULL,
+	},
+	.block_size = MMC_BLOCK_SIZE,
+};
+
+static uintptr_t storage_dev_handle;
+static const io_dev_connector_t *mmc_dev_con;
+
+static const io_block_spec_t bl32_block_spec = {
+	.offset = BL32_BASE,
+	.length = STM32MP1_BL32_SIZE
+};
+
+static const io_block_spec_t bl2_block_spec = {
+	.offset = BL2_BASE,
+	.length = STM32MP1_BL2_SIZE,
+};
+
+static const struct stm32image_part_info bl33_partition_spec = {
+	.name = BL33_IMAGE_NAME,
+	.binary_type = BL33_BINARY_TYPE,
+};
+
+enum {
+	IMG_IDX_BL33,
+	IMG_IDX_NUM
+};
+
+static struct stm32image_device_info stm32image_dev_info_spec = {
+	.lba_size = MMC_BLOCK_SIZE,
+	.part_info[IMG_IDX_BL33] = {
+		.name = BL33_IMAGE_NAME,
+		.binary_type = BL33_BINARY_TYPE,
+	},
+};
+
+static io_block_spec_t stm32image_block_spec = {
+	.offset = 0,
+	.length = 0,
+};
+
+static const io_dev_connector_t *stm32image_dev_con;
+
+static int open_dummy(const uintptr_t spec);
+static int open_image(const uintptr_t spec);
+static int open_storage(const uintptr_t spec);
+
+struct plat_io_policy {
+	uintptr_t *dev_handle;
+	uintptr_t image_spec;
+	int (*check)(const uintptr_t spec);
+};
+
+static const struct plat_io_policy policies[] = {
+	[BL2_IMAGE_ID] = {
+		.dev_handle = &dummy_dev_handle,
+		.image_spec = (uintptr_t)&bl2_block_spec,
+		.check = open_dummy
+	},
+	[BL32_IMAGE_ID] = {
+		.dev_handle = &dummy_dev_handle,
+		.image_spec = (uintptr_t)&bl32_block_spec,
+		.check = open_dummy
+	},
+	[BL33_IMAGE_ID] = {
+		.dev_handle = &image_dev_handle,
+		.image_spec = (uintptr_t)&bl33_partition_spec,
+		.check = open_image
+	},
+	[GPT_IMAGE_ID] = {
+		.dev_handle = &storage_dev_handle,
+		.image_spec = (uintptr_t)&gpt_block_spec,
+		.check = open_storage
+	},
+	[STM32_IMAGE_ID] = {
+		.dev_handle = &storage_dev_handle,
+		.image_spec = (uintptr_t)&stm32image_block_spec,
+		.check = open_storage
+	}
+};
+
+static int open_dummy(const uintptr_t spec)
+{
+	return io_dev_init(dummy_dev_handle, 0);
+}
+
+static int open_image(const uintptr_t spec)
+{
+	return io_dev_init(image_dev_handle, 0);
+}
+
+static int open_storage(const uintptr_t spec)
+{
+	return io_dev_init(storage_dev_handle, 0);
+}
+
+static void print_boot_device(boot_api_context_t *boot_context)
+{
+	switch (boot_context->boot_interface_selected) {
+	case BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_SD:
+		INFO("Using SDMMC\n");
+		break;
+	case BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_EMMC:
+		INFO("Using EMMC\n");
+		break;
+	default:
+		ERROR("Boot interface not found\n");
+		panic();
+		break;
+	}
+
+	if (boot_context->boot_interface_instance != 0U) {
+		INFO("  Instance %d\n", boot_context->boot_interface_instance);
+	}
+}
+
+void stm32mp1_io_setup(void)
+{
+	int io_result __unused;
+	uint8_t idx;
+	struct stm32image_part_info *part;
+	struct stm32_sdmmc2_params params;
+	struct mmc_device_info device_info;
+	uintptr_t mmc_default_instance;
+	const partition_entry_t *entry;
+	boot_api_context_t *boot_context =
+		(boot_api_context_t *)stm32mp1_get_boot_ctx_address();
+
+	print_boot_device(boot_context);
+
+	if ((boot_context->boot_partition_used_toboot == 1U) ||
+	    (boot_context->boot_partition_used_toboot == 2U)) {
+		INFO("Boot used partition fsbl%d\n",
+		     boot_context->boot_partition_used_toboot);
+	}
+
+	io_result = register_io_dev_dummy(&dummy_dev_con);
+	assert(io_result == 0);
+
+	io_result = io_dev_open(dummy_dev_con, dummy_dev_spec,
+				&dummy_dev_handle);
+	assert(io_result == 0);
+
+	switch (boot_context->boot_interface_selected) {
+	case BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_SD:
+	case BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_EMMC:
+		dmbsy();
+
+		memset(&params, 0, sizeof(struct stm32_sdmmc2_params));
+
+		if (boot_context->boot_interface_selected ==
+		    BOOT_API_CTX_BOOT_INTERFACE_SEL_FLASH_EMMC) {
+			device_info.mmc_dev_type = MMC_IS_EMMC;
+			mmc_default_instance = STM32MP1_SDMMC2_BASE;
+		} else {
+			device_info.mmc_dev_type = MMC_IS_SD;
+			mmc_default_instance = STM32MP1_SDMMC1_BASE;
+		}
+
+		switch (boot_context->boot_interface_instance) {
+		case 1:
+			params.reg_base = STM32MP1_SDMMC1_BASE;
+			break;
+		case 2:
+			params.reg_base = STM32MP1_SDMMC2_BASE;
+			break;
+		case 3:
+			params.reg_base = STM32MP1_SDMMC3_BASE;
+			break;
+		default:
+			WARN("SDMMC instance not found, using default\n");
+			params.reg_base = mmc_default_instance;
+			break;
+		}
+
+		params.device_info = &device_info;
+		if (stm32_sdmmc2_mmc_init(&params) != 0) {
+			ERROR("SDMMC%u init failed\n",
+			      boot_context->boot_interface_instance);
+			panic();
+		}
+
+		/* Open MMC as a block device to read GPT table */
+		io_result = register_io_dev_block(&mmc_dev_con);
+		if (io_result != 0) {
+			panic();
+		}
+
+		io_result = io_dev_open(mmc_dev_con,
+					(uintptr_t)&mmc_block_dev_spec,
+					&storage_dev_handle);
+		assert(io_result == 0);
+
+		partition_init(GPT_IMAGE_ID);
+
+		io_result = io_dev_close(storage_dev_handle);
+		assert(io_result == 0);
+
+		stm32image_dev_info_spec.device_size =
+			stm32_sdmmc2_mmc_get_device_size();
+
+		for (idx = 0U; idx < IMG_IDX_NUM; idx++) {
+			part = &stm32image_dev_info_spec.part_info[idx];
+			entry = get_partition_entry(part->name);
+			if (entry == NULL) {
+				ERROR("Partition %s not found\n",
+				      part->name);
+				panic();
+			}
+
+			part->part_offset = entry->start;
+			part->bkp_offset = 0U;
+		}
+
+		/*
+		 * Re-open MMC with io_mmc, for better perfs compared to
+		 * io_block.
+		 */
+		io_result = register_io_dev_mmc(&mmc_dev_con);
+		assert(io_result == 0);
+
+		io_result = io_dev_open(mmc_dev_con, 0, &storage_dev_handle);
+		assert(io_result == 0);
+
+		io_result = register_io_dev_stm32image(&stm32image_dev_con);
+		assert(io_result == 0);
+
+		io_result = io_dev_open(stm32image_dev_con,
+					(uintptr_t)&stm32image_dev_info_spec,
+					&image_dev_handle);
+		assert(io_result == 0);
+		break;
+
+	default:
+		ERROR("Boot interface %d not supported\n",
+		      boot_context->boot_interface_selected);
+		break;
+	}
+}
+
+/*
+ * Return an IO device handle and specification which can be used to access
+ * an image. Use this to enforce platform load policy.
+ */
+int plat_get_image_source(unsigned int image_id, uintptr_t *dev_handle,
+			  uintptr_t *image_spec)
+{
+	int rc;
+	const struct plat_io_policy *policy;
+
+	assert(image_id < ARRAY_SIZE(policies));
+
+	policy = &policies[image_id];
+	rc = policy->check(policy->image_spec);
+	if (rc == 0) {
+		*image_spec = policy->image_spec;
+		*dev_handle = *(policy->dev_handle);
+	}
+
+	return rc;
+}
diff --git a/plat/st/common/include/stm32mp_common.h b/plat/st/common/include/stm32mp_common.h
new file mode 100644
index 0000000..11dd845
--- /dev/null
+++ b/plat/st/common/include/stm32mp_common.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2018-2019, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef STM32MP_COMMON_H
+#define STM32MP_COMMON_H
+
+/* Functions to save and get boot context address given by ROM code */
+void stm32mp1_save_boot_ctx_address(uintptr_t address);
+uintptr_t stm32mp1_get_boot_ctx_address(void);
+
+/*
+ * Platform util functions for the GPIO driver
+ * @bank: Target GPIO bank ID as per DT bindings
+ *
+ * Platform shall implement these functions to provide to stm32_gpio
+ * driver the resource reference for a target GPIO bank. That are
+ * memory mapped interface base address, interface offset (see below)
+ * and clock identifier.
+ *
+ * stm32_get_gpio_bank_offset() returns a bank offset that is used to
+ * check DT configuration matches platform implementation of the banks
+ * description.
+ */
+uintptr_t stm32_get_gpio_bank_base(unsigned int bank);
+unsigned long stm32_get_gpio_bank_clock(unsigned int bank);
+uint32_t stm32_get_gpio_bank_offset(unsigned int bank);
+
+/* Initialise the IO layer and register platform IO devices */
+void stm32mp1_io_setup(void);
+
+#endif /* STM32MP_COMMON_H */
diff --git a/plat/st/common/include/stm32mp_dt.h b/plat/st/common/include/stm32mp_dt.h
new file mode 100644
index 0000000..56357db
--- /dev/null
+++ b/plat/st/common/include/stm32mp_dt.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef STM32MP_DT_H
+#define STM32MP_DT_H
+
+#include <stdbool.h>
+
+#define DT_DISABLED		U(0)
+#define DT_NON_SECURE		U(1)
+#define DT_SECURE		U(2)
+#define DT_SHARED		(DT_NON_SECURE | DT_SECURE)
+
+struct dt_node_info {
+	uint32_t base;
+	int32_t clock;
+	int32_t reset;
+	uint32_t status;
+};
+
+/*******************************************************************************
+ * Function and variable prototypes
+ ******************************************************************************/
+int dt_open_and_check(void);
+int fdt_get_address(void **fdt_addr);
+bool fdt_check_node(int node);
+uint8_t fdt_get_status(int node);
+uint32_t fdt_read_uint32_default(int node, const char *prop_name,
+				 uint32_t dflt_value);
+int fdt_read_uint32_array(int node, const char *prop_name,
+			  uint32_t *array, uint32_t count);
+int dt_set_stdout_pinctrl(void);
+void dt_fill_device_info(struct dt_node_info *info, int node);
+int dt_get_node(struct dt_node_info *info, int offset, const char *compat);
+int dt_get_stdout_uart_info(struct dt_node_info *info);
+int dt_get_stdout_node_offset(void);
+uint32_t dt_get_ddr_size(void);
+const char *dt_get_board_model(void);
+
+#endif /* STM32MP_DT_H */
diff --git a/plat/st/common/stm32mp_common.c b/plat/st/common/stm32mp_common.c
new file mode 100644
index 0000000..7744aa0
--- /dev/null
+++ b/plat/st/common/stm32mp_common.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <platform_def.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <dt-bindings/clock/stm32mp1-clks.h>
+#include <plat/common/platform.h>
+
+uintptr_t plat_get_ns_image_entrypoint(void)
+{
+	return BL33_BASE;
+}
+
+unsigned int plat_get_syscnt_freq2(void)
+{
+	return read_cntfrq_el0();
+}
+
+static uintptr_t boot_ctx_address;
+
+void stm32mp1_save_boot_ctx_address(uintptr_t address)
+{
+	boot_ctx_address = address;
+}
+
+uintptr_t stm32mp1_get_boot_ctx_address(void)
+{
+	return boot_ctx_address;
+}
+
+uintptr_t stm32_get_gpio_bank_base(unsigned int bank)
+{
+	if (bank == GPIO_BANK_Z) {
+		return GPIOZ_BASE;
+	}
+
+	assert(GPIO_BANK_A == 0 && bank <= GPIO_BANK_K);
+
+	return GPIOA_BASE + (bank * GPIO_BANK_OFFSET);
+}
+
+unsigned long stm32_get_gpio_bank_clock(unsigned int bank)
+{
+	if (bank == GPIO_BANK_Z) {
+		return GPIOZ;
+	}
+
+	assert(GPIO_BANK_A == 0 && bank <= GPIO_BANK_K);
+
+	return GPIOA + (bank - GPIO_BANK_A);
+}
+
+uint32_t stm32_get_gpio_bank_offset(unsigned int bank)
+{
+	if (bank == GPIO_BANK_Z) {
+		return 0;
+	}
+
+	assert(GPIO_BANK_A == 0 && bank <= GPIO_BANK_K);
+
+	return bank * GPIO_BANK_OFFSET;
+}
diff --git a/plat/st/common/stm32mp_dt.c b/plat/st/common/stm32mp_dt.c
new file mode 100644
index 0000000..2eaa9d9
--- /dev/null
+++ b/plat/st/common/stm32mp_dt.c
@@ -0,0 +1,308 @@
+/*
+ * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+
+#include <libfdt.h>
+
+#include <platform_def.h>
+
+#include <common/debug.h>
+#include <drivers/st/stm32_gpio.h>
+#include <drivers/st/stm32mp1_clk.h>
+#include <drivers/st/stm32mp1_ddr.h>
+#include <drivers/st/stm32mp1_ram.h>
+
+#include <stm32mp_dt.h>
+
+static int fdt_checked;
+
+static void *fdt = (void *)(uintptr_t)STM32MP1_DTB_BASE;
+
+/*******************************************************************************
+ * This function checks device tree file with its header.
+ * Returns 0 on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int dt_open_and_check(void)
+{
+	int ret = fdt_check_header(fdt);
+
+	if (ret == 0) {
+		fdt_checked = 1;
+	}
+
+	return ret;
+}
+
+/*******************************************************************************
+ * This function gets the address of the DT.
+ * If DT is OK, fdt_addr is filled with DT address.
+ * Returns 1 if success, 0 otherwise.
+ ******************************************************************************/
+int fdt_get_address(void **fdt_addr)
+{
+	if (fdt_checked == 1) {
+		*fdt_addr = fdt;
+	}
+
+	return fdt_checked;
+}
+
+/*******************************************************************************
+ * This function check the presence of a node (generic use of fdt library).
+ * Returns true if present, else return false.
+ ******************************************************************************/
+bool fdt_check_node(int node)
+{
+	int len;
+	const char *cchar;
+
+	cchar = fdt_get_name(fdt, node, &len);
+
+	return (cchar != NULL) && (len >= 0);
+}
+
+/*******************************************************************************
+ * This function return global node status (generic use of fdt library).
+ ******************************************************************************/
+uint8_t fdt_get_status(int node)
+{
+	uint8_t status = DT_DISABLED;
+	int len;
+	const char *cchar;
+
+	cchar = fdt_getprop(fdt, node, "status", &len);
+	if ((cchar == NULL) ||
+	    (strncmp(cchar, "okay", (size_t)len) == 0)) {
+		status |= DT_NON_SECURE;
+	}
+
+	cchar = fdt_getprop(fdt, node, "secure-status", &len);
+	if (cchar == NULL) {
+		if (status == DT_NON_SECURE) {
+			status |= DT_SECURE;
+		}
+	} else if (strncmp(cchar, "okay", (size_t)len) == 0) {
+		status |= DT_SECURE;
+	}
+
+	return status;
+}
+
+/*******************************************************************************
+ * This function reads a value of a node property (generic use of fdt
+ * library).
+ * Returns value if success, and a default value if property not found.
+ * Default value is passed as parameter.
+ ******************************************************************************/
+uint32_t fdt_read_uint32_default(int node, const char *prop_name,
+				 uint32_t dflt_value)
+{
+	const fdt32_t *cuint;
+	int lenp;
+
+	cuint = fdt_getprop(fdt, node, prop_name, &lenp);
+	if (cuint == NULL) {
+		return dflt_value;
+	}
+
+	return fdt32_to_cpu(*cuint);
+}
+
+/*******************************************************************************
+ * This function reads a series of parameters in a node property
+ * (generic use of fdt library).
+ * It reads the values inside the device tree, from property name and node.
+ * The number of parameters is also indicated as entry parameter.
+ * Returns 0 on success and a negative FDT error code on failure.
+ * If success, values are stored at the third parameter address.
+ ******************************************************************************/
+int fdt_read_uint32_array(int node, const char *prop_name, uint32_t *array,
+			  uint32_t count)
+{
+	const fdt32_t *cuint;
+	int len;
+	uint32_t i;
+
+	cuint = fdt_getprop(fdt, node, prop_name, &len);
+	if (cuint == NULL) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	if ((uint32_t)len != (count * sizeof(uint32_t))) {
+		return -FDT_ERR_BADLAYOUT;
+	}
+
+	for (i = 0; i < ((uint32_t)len / sizeof(uint32_t)); i++) {
+		*array = fdt32_to_cpu(*cuint);
+		array++;
+		cuint++;
+	}
+
+	return 0;
+}
+
+/*******************************************************************************
+ * This function gets the stdout pin configuration information from the DT.
+ * And then calls the sub-function to treat it and set GPIO registers.
+ * Returns 0 on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int dt_set_stdout_pinctrl(void)
+{
+	int node;
+
+	node = dt_get_stdout_node_offset();
+	if (node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	return dt_set_pinctrl_config(node);
+}
+
+/*******************************************************************************
+ * This function fills the generic information from a given node.
+ ******************************************************************************/
+void dt_fill_device_info(struct dt_node_info *info, int node)
+{
+	const fdt32_t *cuint;
+
+	cuint = fdt_getprop(fdt, node, "reg", NULL);
+	if (cuint != NULL) {
+		info->base = fdt32_to_cpu(*cuint);
+	} else {
+		info->base = 0;
+	}
+
+	cuint = fdt_getprop(fdt, node, "clocks", NULL);
+	if (cuint != NULL) {
+		cuint++;
+		info->clock = (int)fdt32_to_cpu(*cuint);
+	} else {
+		info->clock = -1;
+	}
+
+	cuint = fdt_getprop(fdt, node, "resets", NULL);
+	if (cuint != NULL) {
+		cuint++;
+		info->reset = (int)fdt32_to_cpu(*cuint);
+	} else {
+		info->reset = -1;
+	}
+
+	info->status = fdt_get_status(node);
+}
+
+/*******************************************************************************
+ * This function retrieve the generic information from DT.
+ * Returns node on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int dt_get_node(struct dt_node_info *info, int offset, const char *compat)
+{
+	int node;
+
+	node = fdt_node_offset_by_compatible(fdt, offset, compat);
+	if (node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	dt_fill_device_info(info, node);
+
+	return node;
+}
+
+/*******************************************************************************
+ * This function gets the UART instance info of stdout from the DT.
+ * Returns node on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int dt_get_stdout_uart_info(struct dt_node_info *info)
+{
+	int node;
+
+	node = dt_get_stdout_node_offset();
+	if (node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	dt_fill_device_info(info, node);
+
+	return node;
+}
+
+/*******************************************************************************
+ * This function gets the stdout path node.
+ * It reads the value indicated inside the device tree.
+ * Returns node if success, and a negative value else.
+ ******************************************************************************/
+int dt_get_stdout_node_offset(void)
+{
+	int node;
+	const char *cchar;
+
+	node = fdt_path_offset(fdt, "/chosen");
+	if (node < 0) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	cchar = fdt_getprop(fdt, node, "stdout-path", NULL);
+	if (cchar == NULL) {
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	node = -FDT_ERR_NOTFOUND;
+	if (strchr(cchar, (int)':') != NULL) {
+		const char *name;
+		char *str = (char *)cchar;
+		int len = 0;
+
+		while (strncmp(":", str, 1)) {
+			len++;
+			str++;
+		}
+
+		name = fdt_get_alias_namelen(fdt, cchar, len);
+
+		if (name != NULL) {
+			node = fdt_path_offset(fdt, name);
+		}
+	} else {
+		node = fdt_path_offset(fdt, cchar);
+	}
+
+	return node;
+}
+
+/*******************************************************************************
+ * This function gets DDR size information from the DT.
+ * Returns value in bytes on success, and 0 on failure.
+ ******************************************************************************/
+uint32_t dt_get_ddr_size(void)
+{
+	int node;
+
+	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
+	if (node < 0) {
+		INFO("%s: Cannot read DDR node in DT\n", __func__);
+		return 0;
+	}
+
+	return fdt_read_uint32_default(node, "st,mem-size", 0);
+}
+
+/*******************************************************************************
+ * This function retrieves board model from DT
+ * Returns string taken from model node, NULL otherwise
+ ******************************************************************************/
+const char *dt_get_board_model(void)
+{
+	int node = fdt_path_offset(fdt, "/");
+
+	if (node < 0) {
+		return NULL;
+	}
+
+	return (const char *)fdt_getprop(fdt, node, "model", NULL);
+}