feat(rpi3): implement eventlog handoff to BL33

At the end of BL2 measured boot, write the address
and size of the TCG Event Log to NT_FW_CONFIG so
that the log can be consumed later by BL33.
-add dynamic configuration helpers for the fdt
-write the eventlog address and size to the fdt

Change-Id: I099dd9cc96d740ae13cb8b8e8c6b9f2e6c02accc
Signed-off-by: Abhi Singh <abhi.singh@arm.com>

plat/rpi/rpi3/include/platform_def.h

@@ -266,4 +266,10 @@
  */
 #define PLAT_ARM_EVENT_LOG_MAX_SIZE UL(0x400)
 
+/*
+ * NT_FW_CONFIG magic dram addr and max size
+ */
+#define PLAT_RPI3_DTO_BASE          ULL(0x11530000)
+#define PLAT_RPI3_DTO_MAX_SIZE      ULL(0x001000)
+
 #endif /* PLATFORM_DEF_H */

plat/rpi/rpi3/include/rpi3_measured_boot.h

@@ -13,4 +13,6 @@
 
 void rpi3_mboot_fetch_eventlog_info(uint8_t **eventlog_addr, size_t *eventlog_size);
 
+int rpi3_set_nt_fw_info(size_t log_size, uintptr_t *ns_log_addr);
+
 #endif /* RPI3_MEASURED_BOOT_H */

plat/rpi/rpi3/platform.mk

@@ -8,7 +8,8 @@ include lib/libfdt/libfdt.mk
 include lib/xlat_tables_v2/xlat_tables.mk
 
 PLAT_INCLUDES		:=	-Iplat/rpi/common/include		\
-				-Iplat/rpi/rpi3/include
+				-Iplat/rpi/rpi3/include			\
+				-Iinclude/lib/libfdt
 
 PLAT_BL_COMMON_SOURCES	:=	drivers/ti/uart/aarch64/16550_console.S	\
 				drivers/arm/pl011/aarch64/pl011_console.S \
@@ -28,7 +29,10 @@ include ${MEASURED_BOOT_MK}
 PLAT_BL_COMMON_SOURCES	+=	${EVENT_LOG_SOURCES}
 
 BL1_SOURCES		+= 	plat/rpi/rpi3/rpi3_bl1_mboot.c
-BL2_SOURCES		+= 	plat/rpi/rpi3/rpi3_bl2_mboot.c
+BL2_SOURCES		+= 	plat/rpi/rpi3/rpi3_bl2_mboot.c		\
+				plat/rpi/rpi3/rpi3_dyn_cfg_helpers.c	\
+				common/fdt_wrappers.c			\
+				common/fdt_fixup.c
 
 CRYPTO_SOURCES		:=	drivers/auth/crypto_mod.c
 

plat/rpi/rpi3/rpi3_bl2_mboot.c

@@ -43,11 +43,36 @@ void bl2_plat_mboot_init(void)
 
 void bl2_plat_mboot_finish(void)
 {
+	int rc;
+
+	/* Event Log address in Non-Secure memory */
+	uintptr_t ns_log_addr;
+
 	/* Event Log filled size */
 	size_t event_log_cur_size;
 
 	event_log_cur_size = event_log_get_cur_size((uint8_t *)event_log_start);
 
+	/* write the eventlog addr and size to NT_FW_CONFIG TPM entry */
+	rc = rpi3_set_nt_fw_info(event_log_cur_size, &ns_log_addr);
+	if (rc != 0) {
+		ERROR("%s(): Unable to update %s_FW_CONFIG\n",
+			__func__, "NT");
+		/*
+		 * fatal error due to Bl33 maintaining the assumption
+		 * that the eventlog is successfully passed via
+		 * NT_FW_CONFIG.
+		 */
+		panic();
+	}
+
+	/* Copy Event Log to Non-secure memory */
+	(void)memcpy((void *)ns_log_addr, (const void *)event_log_start,
+		     event_log_cur_size);
+
+	/* Ensure that the Event Log is visible in Non-secure memory */
+	flush_dcache_range(ns_log_addr, event_log_cur_size);
+
 	/* Dump Event Log for user view */
 	dump_event_log((uint8_t *)event_log_start, event_log_cur_size);
 }

plat/rpi/rpi3/rpi3_dyn_cfg_helpers.c

@@ -0,0 +1,198 @@
+/*
+ * Copyright (c) 2025, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <arch_helpers.h>
+#include <common/desc_image_load.h>
+#include <common/fdt_wrappers.h>
+#include <libfdt.h>
+#include <platform_def.h>
+
+#define DTB_PROP_HW_LOG_ADDR	"tpm_event_log_addr"
+#define DTB_PROP_HW_LOG_SIZE	"tpm_event_log_size"
+
+static int rpi3_event_log_fdt_init_overlay(uintptr_t dt_base, int dt_size)
+{
+	int ret;
+	int offset;
+	void *dtb = (void *)dt_base;
+
+	ret = fdt_create_empty_tree(dtb, dt_size);
+	if (ret < 0) {
+		ERROR("cannot create empty dtb tree: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	offset = fdt_path_offset(dtb, "/");
+	if (offset < 0) {
+		ERROR("cannot find root of the tree: %s\n",
+		       fdt_strerror(offset));
+		return offset;
+	}
+
+	offset = fdt_add_subnode(dtb, offset, "fragment@0");
+	if (offset < 0) {
+		ERROR("cannot add fragment node: %s\n",
+		       fdt_strerror(offset));
+		return offset;
+	}
+
+	ret = fdt_setprop_string(dtb, offset, "target-path", "/");
+	if (ret < 0) {
+		ERROR("cannot set target-path property: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	offset = fdt_add_subnode(dtb, offset, "__overlay__");
+	if (offset < 0) {
+		ERROR("cannot add __overlay__ node: %s\n",
+		       fdt_strerror(offset));
+		return ret;
+	}
+
+	offset = fdt_add_subnode(dtb, offset, "tpm_event_log");
+	if (offset < 0) {
+		ERROR("cannot add tpm_event_log node: %s\n",
+		       fdt_strerror(offset));
+		return offset;
+	}
+
+	ret = fdt_setprop_string(dtb, offset, "compatible",
+				 "arm,tpm_event_log");
+	if (ret < 0) {
+		ERROR("cannot set compatible property: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	ret = fdt_setprop_u64(dtb, offset, "tpm_event_log_addr", 0);
+	if (ret < 0) {
+		ERROR("cannot set tpm_event_log_addr property: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	ret = fdt_setprop_u32(dtb, offset, "tpm_event_log_size", 0);
+	if (ret < 0) {
+		ERROR("cannot set tpm_event_log_size property: %s\n",
+		       fdt_strerror(ret));
+		return ret;
+	}
+
+	return ret;
+}
+
+/*
+ * Write the Event Log address and its size in the DTB.
+ *
+ * This function is supposed to be called only by BL2.
+ *
+ * Returns:
+ *	0 = success
+ *    < 0 = error
+ */
+static int rpi3_set_event_log_info(uintptr_t config_base,
+				  uintptr_t log_addr, size_t log_size)
+{
+	/* As libfdt uses void *, we can't avoid this cast */
+	void *dtb = (void *)config_base;
+	/* compatible is set based on the following tpm_tis_spi guidelines from
+	 * https://www.kernel.org/doc/Documentation/devicetree/bindings
+	 * /security/tpm/tpm_tis_spi.txt
+	 */
+	const char *compatible_tpm = "arm,tpm_event_log";
+	uint64_t base = cpu_to_fdt64(log_addr);
+	uint32_t sz = cpu_to_fdt32(log_size);
+	int err, node;
+
+	err = fdt_open_into(dtb, dtb, PLAT_RPI3_DTO_MAX_SIZE);
+	if (err < 0) {
+		ERROR("Invalid Device Tree at %p: error %d\n", dtb, err);
+		return err;
+	}
+
+	/*
+	 * Verify that the DTB is valid, before attempting to write to it,
+	 * and get the DTB root node.
+	 */
+
+	/* Check if the pointer to DT is correct */
+	err = fdt_check_header(dtb);
+	if (err < 0) {
+		WARN("Invalid DTB file passed\n");
+		return err;
+	}
+
+	/*
+	 * Find the TPM node in device tree.
+	 */
+	node = fdt_node_offset_by_compatible(dtb, -1, compatible_tpm);
+	if (node < 0) {
+		ERROR("The compatible property '%s' not%s", compatible_tpm,
+			" found in the config\n");
+		return node;
+	}
+
+	err = fdt_setprop(dtb, node, DTB_PROP_HW_LOG_ADDR, &base, 8);
+	if (err < 0) {
+		ERROR("Failed to add log addr err %d\n", err);
+		return err;
+	}
+
+	err = fdt_setprop(dtb, node, DTB_PROP_HW_LOG_SIZE, &sz, 4);
+	if (err < 0) {
+		ERROR("Failed to add log size err %d\n", err);
+		return err;
+	}
+
+	err = fdt_pack(dtb);
+	if (err < 0) {
+		ERROR("Failed to pack Device Tree at %p: error %d\n", dtb, err);
+		return err;
+	}
+
+	/*
+	 * Ensure that the info written to the DTB is visible
+	 * to other images.
+	 */
+	flush_dcache_range(config_base, fdt_totalsize(dtb));
+
+	return err;
+}
+
+/*
+ * This function writes the Event Log address and its size
+ * in the RPi3 DTB.
+ *
+ * This function is supposed to be called only by BL2.
+ *
+ * Returns:
+ *	0 = success
+ *    < 0 = error
+ */
+int rpi3_set_nt_fw_info(size_t log_size, uintptr_t *ns_log_addr)
+{
+	uintptr_t ns_addr;
+	int err;
+
+	assert(ns_log_addr != NULL);
+
+	ns_addr = PLAT_RPI3_DTO_BASE + PLAT_RPI3_DTO_MAX_SIZE;
+
+	rpi3_event_log_fdt_init_overlay(PLAT_RPI3_DTO_BASE,
+					  PLAT_RPI3_DTO_MAX_SIZE);
+
+	/* Write the Event Log address and its size in the DTB */
+	err = rpi3_set_event_log_info(PLAT_RPI3_DTO_BASE,
+					ns_addr, log_size);
+
+	/* Return Event Log address in Non-secure memory */
+	*ns_log_addr = (err < 0) ? 0UL : ns_addr;
+	return err;
+}