ARM Platforms: Load HW_CONFIG in BL2

The patch adds the necessary changes to load HW_CONFIG in BL2 for
ARM Platforms :

1. The load address of HW_CONFIG is specified via the `hw_config_addr`
property in TB_FW_CONFIG is loaded by BL1. The `hw_config_max_size`
property defines the maximum size to be expected for the HW_CONFIG.
The `arm_dyn_cfg_helpers.c` and corresponding header implements
utility functions to parse these DT properties defined.
The `arm_dyn_cfg.c` implements wrappers to these helpers to enable
them to be invoked from ARM platform layer.

2. `HW_CONFIG` is added to the `bl2_mem_params_descs[]` array which is
the list of images to be loaded by BL2.

3. The `libfdt` sources are now included when BL2 is built

4. A new helper `populate_next_bl_params_config()` is introduced in
desc_image_load.c to populate the subsequent executable BL images
with the `hw_config` and the corresponding `fw_config` if available.
The `plat_get_next_bl_params()` API for ARM platforms is modified to
invoke this new helper.

5. The implementation of `bl2_early_platform_setup2()` is modified to
consider `arg0` as well in addition to `arg1` passed from BL1.

6. Bump up the BL2 size for Juno to accommodate the inclusion of libfdt.

Change-Id: I80f1554adec41753e0d179a5237364f04fe13a3f
Signed-off-by: Soby Mathew <soby.mathew@arm.com>

common/desc_image_load.c

@@ -190,3 +190,65 @@ bl_params_t *get_next_bl_params_from_mem_params_desc(void)
 
 	return &next_bl_params;
 }
+
+/*******************************************************************************
+ * This function populates the entry point information with the corresponding
+ * config file for all executable BL images described in bl_params.
+ ******************************************************************************/
+void populate_next_bl_params_config(bl_params_t *bl2_to_next_bl_params)
+{
+	bl_params_node_t *params_node;
+	unsigned int fw_config_id;
+	uintptr_t hw_config_base = 0, fw_config_base;
+	bl_mem_params_node_t *mem_params;
+
+	assert(bl2_to_next_bl_params);
+
+	/*
+	 * Get the `bl_mem_params_node_t` corresponding to HW_CONFIG
+	 * if available.
+	 */
+	mem_params = get_bl_mem_params_node(HW_CONFIG_ID);
+	if (mem_params != NULL)
+		hw_config_base = mem_params->image_info.image_base;
+
+	for (params_node = bl2_to_next_bl_params->head; params_node != NULL;
+			params_node = params_node->next_params_info) {
+
+		fw_config_base = 0;
+
+		switch (params_node->image_id) {
+		case BL31_IMAGE_ID:
+			fw_config_id = SOC_FW_CONFIG_ID;
+			break;
+		case BL32_IMAGE_ID:
+			fw_config_id = TOS_FW_CONFIG_ID;
+			break;
+		case BL33_IMAGE_ID:
+			fw_config_id = NT_FW_CONFIG_ID;
+			break;
+		default:
+			fw_config_id = INVALID_IMAGE_ID;
+			break;
+		}
+
+		if (fw_config_id != INVALID_IMAGE_ID) {
+			mem_params = get_bl_mem_params_node(fw_config_id);
+			if (mem_params != NULL)
+				fw_config_base = mem_params->image_info.image_base;
+		}
+
+		/*
+		 * Pass hw and tb_fw config addresses to next images. NOTE - for
+		 * EL3 runtime images (BL31 for AArch64 and BL32 for AArch32),
+		 * arg0 is already used by generic code.
+		 */
+		if (params_node == bl2_to_next_bl_params->head) {
+			params_node->ep_info->args.arg1 = fw_config_base;
+			params_node->ep_info->args.arg2 = hw_config_base;
+		} else {
+			params_node->ep_info->args.arg0 = fw_config_base;
+			params_node->ep_info->args.arg1 = hw_config_base;
+		}
+	}
+}

include/common/desc_image_load.h

@@ -33,7 +33,7 @@ int get_bl_params_node_index(unsigned int image_id);
 bl_mem_params_node_t *get_bl_mem_params_node(unsigned int image_id);
 bl_load_info_t *get_bl_load_info_from_mem_params_desc(void);
 bl_params_t *get_next_bl_params_from_mem_params_desc(void);
-
+void populate_next_bl_params_config(bl_params_t *bl2_to_next_bl_params);
 
 #endif /* LOAD_IMAGE_V2 */
 #endif /* __DESC_IMAGE_LOAD_H__ */

include/plat/arm/board/common/board_arm_def.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

include/plat/arm/common/arm_dyn_cfg_helpers.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+#ifndef __ARM_DYN_CFG_HELPERS_H__
+#define __ARM_DYN_CFG_HELPERS_H__
+
+#include <stdint.h>
+
+/* Function declaration */
+int arm_dyn_get_hwconfig_info(void *dtb, int node,
+		uint64_t *hw_config_addr, uint32_t *hw_config_size);
+int arm_dyn_tb_fw_cfg_init(void *dtb, int *node);
+
+#endif /* __ARM_DYN_CFG_HELPERS_H__ */

include/plat/arm/common/plat_arm.h

@@ -19,6 +19,7 @@
 struct bl31_params;
 struct meminfo;
 struct image_info;
+struct bl_params;
 
 #define ARM_CASSERT_MMAP						\
 	CASSERT((ARRAY_SIZE(plat_arm_mmap) + ARM_BL_REGIONS)		\
@@ -138,7 +139,7 @@ void arm_bl1_platform_setup(void);
 void arm_bl1_plat_arch_setup(void);
 
 /* BL2 utility functions */
-void arm_bl2_early_platform_setup(struct meminfo *mem_layout);
+void arm_bl2_early_platform_setup(uintptr_t tb_fw_config, struct meminfo *mem_layout);
 void arm_bl2_platform_setup(void);
 void arm_bl2_plat_arch_setup(void);
 uint32_t arm_get_spsr_for_bl32_entry(void);
@@ -180,6 +181,8 @@ int arm_io_is_toc_valid(void);
 
 /* Utility functions for Dynamic Config */
 void arm_load_tb_fw_config(void);
+void arm_bl2_set_tb_cfg_addr(void *dtb);
+void arm_bl2_dyn_cfg_init(void);
 
 /*
  * Mandatory functions required in ARM standard platforms

plat/arm/board/fvp/fvp_bl2_setup.c

@@ -14,7 +14,7 @@
 
 void bl2_early_platform_setup2(u_register_t arg0, u_register_t arg1, u_register_t arg2, u_register_t arg3)
 {
-	arm_bl2_early_platform_setup((meminfo_t *)arg1);
+	arm_bl2_early_platform_setup((uintptr_t)arg0, (meminfo_t *)arg1);
 
 	/* Initialize the platform config for future decision making */
 	fvp_config_setup();

plat/arm/board/fvp/fvp_io_storage.c

@@ -19,6 +19,7 @@
 #define BL32_IMAGE_NAME			"bl32.bin"
 #define BL33_IMAGE_NAME			"bl33.bin"
 #define TB_FW_CONFIG_NAME		"fvp_tb_fw_config.dtb"
+#define HW_CONFIG_NAME			"hw_config.dtb"
 
 #if TRUSTED_BOARD_BOOT
 #define TRUSTED_BOOT_FW_CERT_NAME	"tb_fw.crt"
@@ -56,6 +57,10 @@ static const io_file_spec_t sh_file_spec[] = {
 		.path = TB_FW_CONFIG_NAME,
 		.mode = FOPEN_MODE_RB
 	},
+	[HW_CONFIG_ID] = {
+		.path = HW_CONFIG_NAME,
+		.mode = FOPEN_MODE_RB
+	},
 #if TRUSTED_BOARD_BOOT
 	[TRUSTED_BOOT_FW_CERT_ID] = {
 		.path = TRUSTED_BOOT_FW_CERT_NAME,

plat/arm/board/juno/include/platform_def.h

@@ -110,12 +110,12 @@
  */
 #if TRUSTED_BOARD_BOOT
 #if TF_MBEDTLS_KEY_ALG_ID == TF_MBEDTLS_RSA_AND_ECDSA
-# define PLAT_ARM_MAX_BL2_SIZE		0x1E000
+# define PLAT_ARM_MAX_BL2_SIZE		0x1F000
 #else
-# define PLAT_ARM_MAX_BL2_SIZE		0x1A000
+# define PLAT_ARM_MAX_BL2_SIZE		0x1B000
 #endif
 #else
-# define PLAT_ARM_MAX_BL2_SIZE		0xC000
+# define PLAT_ARM_MAX_BL2_SIZE		0xD000
 #endif
 
 /*

plat/arm/common/aarch32/arm_bl2_mem_params_desc.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -54,7 +54,15 @@ static bl_mem_params_node_t bl2_mem_params_descs[] = {
 
 	    .next_handoff_image_id = BL33_IMAGE_ID,
     },
-
+	/* Fill HW_CONFIG related information if it exists */
+    {
+	    .image_id = HW_CONFIG_ID,
+	    SET_STATIC_PARAM_HEAD(ep_info, PARAM_IMAGE_BINARY,
+		    VERSION_2, entry_point_info_t, NON_SECURE | NON_EXECUTABLE),
+	    SET_STATIC_PARAM_HEAD(image_info, PARAM_IMAGE_BINARY,
+		    VERSION_2, image_info_t, IMAGE_ATTRIB_SKIP_LOADING),
+	    .next_handoff_image_id = INVALID_IMAGE_ID,
+    },
 	/* Fill BL33 related information */
     {
 	    .image_id = BL33_IMAGE_ID,

plat/arm/common/aarch64/arm_bl2_mem_params_desc.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -82,7 +82,15 @@ static bl_mem_params_node_t bl2_mem_params_descs[] = {
 	    .next_handoff_image_id = BL33_IMAGE_ID,
 # endif
     },
-
+	/* Fill HW_CONFIG related information */
+    {
+	    .image_id = HW_CONFIG_ID,
+	    SET_STATIC_PARAM_HEAD(ep_info, PARAM_IMAGE_BINARY,
+		    VERSION_2, entry_point_info_t, NON_SECURE | NON_EXECUTABLE),
+	    SET_STATIC_PARAM_HEAD(image_info, PARAM_IMAGE_BINARY,
+		    VERSION_2, image_info_t, IMAGE_ATTRIB_SKIP_LOADING),
+	    .next_handoff_image_id = INVALID_IMAGE_ID,
+    },
 # ifdef BL32_BASE
 	/* Fill BL32 related information */
     {

plat/arm/common/arm_bl2_setup.c

@@ -181,7 +181,7 @@ struct entry_point_info *bl2_plat_get_bl31_ep_info(void)
  * in x0. This memory layout is sitting at the base of the free trusted SRAM.
  * Copy it to a safe location before its reclaimed by later BL2 functionality.
  ******************************************************************************/
-void arm_bl2_early_platform_setup(meminfo_t *mem_layout)
+void arm_bl2_early_platform_setup(uintptr_t tb_fw_config, meminfo_t *mem_layout)
 {
 	/* Initialize the console to provide early debug support */
 	console_init(PLAT_ARM_BOOT_UART_BASE, PLAT_ARM_BOOT_UART_CLK_IN_HZ,
@@ -192,11 +192,17 @@ void arm_bl2_early_platform_setup(meminfo_t *mem_layout)
 
 	/* Initialise the IO layer and register platform IO devices */
 	plat_arm_io_setup();
+
+#if LOAD_IMAGE_V2
+	if (tb_fw_config != 0)
+		arm_bl2_set_tb_cfg_addr((void *)tb_fw_config);
+#endif
 }
 
 void bl2_early_platform_setup2(u_register_t arg0, u_register_t arg1, u_register_t arg2, u_register_t arg3)
 {
-	arm_bl2_early_platform_setup((meminfo_t *)arg1);
+	arm_bl2_early_platform_setup((uintptr_t)arg0, (meminfo_t *)arg1);
+
 	generic_delay_timer_init();
 }
 
@@ -205,6 +211,10 @@ void bl2_early_platform_setup2(u_register_t arg0, u_register_t arg1, u_register_
  */
 void arm_bl2_platform_setup(void)
 {
+#if LOAD_IMAGE_V2
+	arm_bl2_dyn_cfg_init();
+#endif
+
 	/* Initialize the secure environment */
 	plat_arm_security_setup();
 

plat/arm/common/arm_common.mk

@@ -152,6 +152,13 @@ BL2_SOURCES		+=	drivers/delay_timer/delay_timer.c		\
 				plat/arm/common/arm_bl2_setup.c			\
 				plat/arm/common/arm_io_storage.c
 
+# Add `libfdt` and Arm common helpers required for Dynamic Config
+include lib/libfdt/libfdt.mk
+BL2_SOURCES		+=	plat/arm/common/arm_dyn_cfg.c		\
+				plat/arm/common/arm_dyn_cfg_helpers.c	\
+				common/fdt_wrappers.c			\
+				${LIBFDT_SRCS}
+
 ifeq (${BL2_AT_EL3},1)
 BL2_SOURCES		+=	plat/arm/common/arm_bl2_el3_setup.c
 endif

plat/arm/common/arm_dyn_cfg.c

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <arm_dyn_cfg_helpers.h>
 #include <assert.h>
 #include <debug.h>
 #include <desc_image_load.h>
@@ -14,6 +15,9 @@
 
 #if LOAD_IMAGE_V2
 
+/* Variable to store the address to TB_FW_CONFIG passed from BL1 */
+static void *tb_fw_cfg_dtb;
+
 /*
  * Helper function to load TB_FW_CONFIG and populate the load information to
  * arg0 of BL2 entrypoint info.
@@ -51,4 +55,54 @@ void arm_load_tb_fw_config(void)
 			(void *) config_base);
 }
 
+/*
+ * BL2 utility function to set the address of TB_FW_CONFIG passed from BL1.
+ */
+void arm_bl2_set_tb_cfg_addr(void *dtb)
+{
+	assert(dtb);
+	tb_fw_cfg_dtb = dtb;
+}
+
+/*
+ * BL2 utility function to initialize dynamic configuration specified by
+ * TB_FW_CONFIG. Return early if TB_FW_CONFIG is not found or HW_CONFIG is
+ * not specified in TB_FW_CONFIG.
+ */
+void arm_bl2_dyn_cfg_init(void)
+{
+	int err = 0;
+	int tb_fw_node;
+	bl_mem_params_node_t *hw_cfg_mem_params = NULL;
+
+	if (tb_fw_cfg_dtb == NULL) {
+		VERBOSE("No TB_FW_CONFIG specified\n");
+		return;
+	}
+
+	err = arm_dyn_tb_fw_cfg_init((void *)tb_fw_cfg_dtb, &tb_fw_node);
+	if (err < 0) {
+		ERROR("Invalid TB_FW_CONFIG passed from BL1\n");
+		panic();
+	}
+
+	/* Get the hw_config load address and size from TB_FW_CONFIG */
+	hw_cfg_mem_params = get_bl_mem_params_node(HW_CONFIG_ID);
+	if (hw_cfg_mem_params == NULL) {
+		VERBOSE("Couldn't find HW_CONFIG in bl_mem_params_node\n");
+		return;
+	}
+
+	err = arm_dyn_get_hwconfig_info((void *)tb_fw_cfg_dtb, tb_fw_node,
+		(uint64_t *) &hw_cfg_mem_params->image_info.image_base,
+		&hw_cfg_mem_params->image_info.image_max_size);
+	if (err < 0) {
+		VERBOSE("Couldn't find HW_CONFIG load info in TB_FW_CONFIG\n");
+		return;
+	}
+
+	/* Remove the IMAGE_ATTRIB_SKIP_LOADING attribute from HW_CONFIG node */
+	hw_cfg_mem_params->image_info.h.attr &= ~IMAGE_ATTRIB_SKIP_LOADING;
+}
+
 #endif /* LOAD_IMAGE_V2 */

plat/arm/common/arm_dyn_cfg_helpers.c

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <desc_image_load.h>
+#include <fdt_wrappers.h>
+#include <libfdt.h>
+
+/*******************************************************************************
+ * Helper to read the `hw_config` property in config DTB. This function
+ * expects the following properties to be present in the config DTB.
+ *	name : hw_config_addr		size : 2 cells
+ *	name : hw_config_max_size	size : 1 cell
+ *
+ * Arguments:
+ *	void *dtb		 - pointer to the TB_FW_CONFIG in memory
+ *	int node		 - The node offset to appropriate node in the
+ *					 DTB.
+ *	uint64_t *hw_config_addr - Returns the `hw_config` load address if read
+ *					 is successful.
+ *	uint32_t *hw_config_size - Returns the `hw_config` size if read is
+ *					 successful.
+ *
+ * Returns 0 on success and -1 on error.
+ ******************************************************************************/
+int arm_dyn_get_hwconfig_info(void *dtb, int node,
+		uint64_t *hw_config_addr, uint32_t *hw_config_size)
+{
+	int err;
+
+	assert(dtb);
+	assert(hw_config_addr);
+	assert(hw_config_size);
+
+	/* Check if the pointer to DT is correct */
+	assert(fdt_check_header(dtb) == 0);
+
+	/* Assert the node offset point to "arm,tb_fw" compatible property */
+	assert(node == fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw"));
+
+	err = fdtw_read_cells(dtb, node, "hw_config_addr", 2,
+				(void *) hw_config_addr);
+	if (err < 0) {
+		WARN("Read cell failed for hw_config_addr\n");
+		return -1;
+	}
+
+	err = fdtw_read_cells(dtb, node, "hw_config_max_size", 1,
+				(void *) hw_config_size);
+	if (err < 0) {
+		WARN("Read cell failed for hw_config_max_size\n");
+		return -1;
+	}
+
+	VERBOSE("Dyn cfg: Read hw_config address from TB_FW_CONFIG 0x%p %p\n",
+				hw_config_addr, hw_config_size);
+
+	return 0;
+}
+
+/*******************************************************************************
+ * Validate the tb_fw_config is a valid DTB file and returns the node offset
+ * to "arm,tb_fw" property.
+ * Arguments:
+ *	void *dtb - pointer to the TB_FW_CONFIG in memory
+ *	int *node - Returns the node offset to "arm,tb_fw" property if found.
+ *
+ * Returns 0 on success and -1 on error.
+ ******************************************************************************/
+int arm_dyn_tb_fw_cfg_init(void *dtb, int *node)
+{
+	assert(dtb);
+	assert(node);
+
+	/* Check if the pointer to DT is correct */
+	if (fdt_check_header(dtb) != 0) {
+		WARN("Invalid DTB file passed as TB_FW_CONFIG\n");
+		return -1;
+	}
+
+	/* Assert the node offset point to "arm,tb_fw" compatible property */
+	*node = fdt_node_offset_by_compatible(dtb, -1, "arm,tb_fw");
+	if (*node < 0) {
+		WARN("The compatible property `arm,tb_fw` not found in the config\n");
+		return -1;
+	}
+
+	VERBOSE("Dyn cfg: Found \"arm,tb_fw\" in the config\n");
+	return 0;
+}

plat/arm/common/arm_image_load.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -7,6 +7,7 @@
 #include <arm_def.h>
 #include <bl_common.h>
 #include <desc_image_load.h>
+#include <plat_arm.h>
 #include <platform.h>
 
 
@@ -37,5 +38,8 @@ bl_load_info_t *plat_get_bl_image_load_info(void)
  ******************************************************************************/
 bl_params_t *plat_get_next_bl_params(void)
 {
-	return get_next_bl_params_from_mem_params_desc();
+	bl_params_t *next_bl_params = get_next_bl_params_from_mem_params_desc();
+
+	populate_next_bl_params_config(next_bl_params);
+	return next_bl_params;
 }

plat/arm/common/arm_io_storage.c

@@ -57,6 +57,10 @@ static const io_uuid_spec_t tb_fw_config_uuid_spec = {
 	.uuid = UUID_TB_FW_CONFIG,
 };
 
+static const io_uuid_spec_t hw_config_uuid_spec = {
+	.uuid = UUID_HW_CONFIG,
+};
+
 #if TRUSTED_BOARD_BOOT
 static const io_uuid_spec_t tb_fw_cert_uuid_spec = {
 	.uuid = UUID_TRUSTED_BOOT_FW_CERT,
@@ -156,6 +160,11 @@ static const struct plat_io_policy policies[] = {
 		(uintptr_t)&tb_fw_config_uuid_spec,
 		open_fip
 	},
+	[HW_CONFIG_ID] = {
+		&fip_dev_handle,
+		(uintptr_t)&hw_config_uuid_spec,
+		open_fip
+	},
 #if TRUSTED_BOARD_BOOT
 	[TRUSTED_BOOT_FW_CERT_ID] = {
 		&fip_dev_handle,