From d859ca03579d966f75fda713e2b4b4f7cf99e938 Mon Sep 17 00:00:00 2001
From: Daniel Jobson <jobson@tillitis.se>
Date: Tue, 3 Sep 2024 15:27:38 +0200
Subject: [PATCH] WIP preload_app

---
 hw/application_fpga/Makefile             |  9 ++-
 hw/application_fpga/fw/tk1/preload_app.c | 84 ++++++++++++++++++++++++
 hw/application_fpga/fw/tk1/preload_app.h | 16 +++++
 3 files changed, 106 insertions(+), 3 deletions(-)
 create mode 100644 hw/application_fpga/fw/tk1/preload_app.c
 create mode 100644 hw/application_fpga/fw/tk1/preload_app.h

diff --git a/hw/application_fpga/Makefile b/hw/application_fpga/Makefile
index fee21f3..0ac6342 100644
--- a/hw/application_fpga/Makefile
+++ b/hw/application_fpga/Makefile
@@ -113,7 +113,8 @@ FIRMWARE_DEPS = \
 	$(P)/fw/tk1/blake2s/blake2s.h \
 	$(P)/fw/tk1/spi.h \
 	$(P)/fw/tk1/flash.h \
-	$(P)/fw/tk1/partition_table.h
+	$(P)/fw/tk1/partition_table.h \
+	$(P)/fw/tk1/preload_app.h
 
 FIRMWARE_OBJS = \
 	$(P)/fw/tk1/main.o \
@@ -125,7 +126,8 @@ FIRMWARE_OBJS = \
 	$(P)/fw/tk1/blake2s/blake2s.o \
 	$(P)/fw/tk1/spi.o \
 	$(P)/fw/tk1/flash.o \
-	$(P)/fw/tk1/partition_table.o
+	$(P)/fw/tk1/partition_table.o \
+	$(P)/fw/tk1/preload_app.o
 
 FIRMWARE_SOURCES = \
 	$(P)/fw/tk1/main.c \
@@ -136,7 +138,8 @@ FIRMWARE_SOURCES = \
 	$(P)/fw/tk1/blake2s/blake2s.c \
 	$(P)/fw/tk1/spi.c \
 	$(P)/fw/tk1/flash.c \
-	$(P)/fw/tk1/partition_table.c
+	$(P)/fw/tk1/partition_table.c \
+	$(P)/fw/tk1/preload_app.c
 
 TESTFW_OBJS = \
 	$(P)/fw/testfw/main.o \
diff --git a/hw/application_fpga/fw/tk1/preload_app.c b/hw/application_fpga/fw/tk1/preload_app.c
new file mode 100644
index 0000000..adb40a3
--- /dev/null
+++ b/hw/application_fpga/fw/tk1/preload_app.c
@@ -0,0 +1,84 @@
+// Copyright (C) 2024 - Tillitis AB
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "preload_app.h"
+#include "../tk1_mem.h"
+#include "flash.h"
+#include "lib.h"
+#include "partition_table.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/* Returns non-zero if the app is valid */
+bool preload_check_valid_app(partition_table_t *part_table)
+{
+
+	if (part_table->pre_app_data.status == 0x00 &&
+	    part_table->pre_app_data.size == 0) {
+		/*No valid app*/
+		return false;
+		// TODO: Should we also check nonce, authentication digest for
+		// non-zero?
+	}
+
+	return true;
+}
+
+/* Loads a preloaded app from flash to app RAM */
+int preload_start(partition_table_t *part_table)
+{
+	/*Check for a valid app in flash	*/
+	if (!preload_check_valid_app(part_table)) {
+		return -1;
+	}
+	uint8_t *loadaddr = (uint8_t *)TK1_RAM_BASE;
+
+	// TODO: Check authentication digest
+	// TODO: Should this function set *app_size?
+
+	/* Read from flash, straight into RAM */
+	int ret = flash_read_data(ADDR_PRE_LOADED_APP, loadaddr,
+				  part_table->pre_app_data.size);
+
+	return ret;
+}
+
+int preload_store(partition_table_t *part_table)
+{
+	// TODO: Can reuse the app loading context  in main, to keep track of
+	// where to store.
+	//  Most likely needs to aggregate some data, before it writes to flash.
+
+	/*Check for a valid app in flash, bale out if it already exists */
+	if (preload_check_valid_app(part_table)) {
+		return -1;
+	}
+
+	return 0;
+}
+
+int preload_delete(partition_table_t *part_table)
+{
+	/*Check for a valid app in flash	*/
+	if (!preload_check_valid_app(part_table)) {
+		return 0;
+		// TODO: Nothing here, return zero like all is good?
+	}
+	part_table->pre_app_data.size = 0;
+	part_table->pre_app_data.status = 0;
+
+	memset(part_table->pre_app_data.auth.nonce, 0x00,
+	       sizeof(part_table->pre_app_data.auth.nonce));
+
+	memset(part_table->pre_app_data.auth.authentication_digest, 0x00,
+	       sizeof(part_table->pre_app_data.auth.authentication_digest));
+
+	part_table_write(part_table);
+
+	flash_block_64_erase(ADDR_PRE_LOADED_APP); // Erase first 64 KB block
+	flash_block_64_erase(ADDR_PRE_LOADED_APP +
+			     0x10000); // Erase second 64 KB block
+
+	return 0;
+}
diff --git a/hw/application_fpga/fw/tk1/preload_app.h b/hw/application_fpga/fw/tk1/preload_app.h
new file mode 100644
index 0000000..ffff4ba
--- /dev/null
+++ b/hw/application_fpga/fw/tk1/preload_app.h
@@ -0,0 +1,16 @@
+// Copyright (C) 2024 - Tillitis AB
+// SPDX-License-Identifier: GPL-2.0-only
+
+#ifndef PRELOAD_APP_H
+#define PRELOAD_APP_H
+
+#include "partition_table.h"
+#include <stdbool.h>
+#include <stdint.h>
+
+bool preload_check_valid_app(partition_table_t *part_table);
+int preload_start(partition_table_t *part_table);
+int preload_store(partition_table_t *part_table);
+int preload_delete(partition_table_t *part_table);
+
+#endif