Refactor the x86 GPT code to be generically available. Upgrade update_disk.c support for other targets.

Author: trini

Makefile

@@ -528,7 +528,7 @@ line-count-nrf52:
 	cloc --force-lang-def cloc_lang_def.txt src/boot_arm.c src/image.c src/libwolfboot.c src/loader.c src/update_flash.c hal/nrf52.c
 
 line-count-x86:
-	cloc --force-lang-def cloc_lang_def.txt src/boot_x86_fsp.c src/boot_x86_fsp_payload.c src/boot_x86_fsp_start.S src/image.c src/keystore.c src/libwolfboot.c src/loader.c src/string.c src/update_disk.c src/x86/ahci.c src/x86/ata.c src/x86/common.c src/x86/gpt.c src/x86/hob.c src/pci.c src/x86/tgl_fsp.c hal/x86_fsp_tgl.c hal/x86_uart.c
+	cloc --force-lang-def cloc_lang_def.txt src/boot_x86_fsp.c src/boot_x86_fsp_payload.c src/boot_x86_fsp_start.S src/image.c src/keystore.c src/libwolfboot.c src/loader.c src/string.c src/update_disk.c src/gpt.c src/x86/ahci.c src/x86/ata.c src/x86/common.c src/x86/disk.c src/x86/hob.c src/pci.c src/x86/tgl_fsp.c hal/x86_fsp_tgl.c hal/x86_uart.c
 
 stack-usage: wolfboot.bin
 	$(Q)echo $(STACK_USAGE) > .stack_usage

arch.mk

@@ -561,7 +561,10 @@ endif
 ifeq ($(ARCH),RISCV64)
   CROSS_COMPILE?=riscv64-unknown-elf-
   CFLAGS+=-DMMU -DWOLFBOOT_DUALBOOT
-  UPDATE_OBJS:=src/update_ram.o
+  #UPDATE_OBJS:=src/update_ram.o
+  UPDATE_OBJS:=src/update_disk.o
+  CFLAGS+=-DWOLFBOOT_UPDATE_DISK
+  OBJS += src/gpt.o
   ARCH_FLAGS=-march=rv64imafdc -mabi=lp64d -mcmodel=medany
   CFLAGS+=-fno-builtin-printf -DUSE_M_TIME -g -nostartfiles -DARCH_RISCV64
   CFLAGS+=$(ARCH_FLAGS)
@@ -1030,6 +1033,9 @@ ifeq ($(filter $(TARGET),x86_fsp_qemu kontron_vx3060_s2),$(TARGET))
     FSP_TGL=1
     CFLAGS+=-DWOLFBOOT_TGL=1
   endif
+
+  # load to address in RAM after wolfBoot (aligned to 16 bytes)
+  CFLAGS+=-DWOLFBOOT_NO_LOAD_ADDRESS
 endif
 
 ifeq ($(TARGET),x86_fsp_qemu)
@@ -1110,7 +1116,8 @@ ifeq ("${FSP}", "1")
     CFLAGS+=-DWOLFBOOT_USE_PCI
     OBJS += src/x86/ahci.o
     OBJS += src/x86/ata.o
-    OBJS += src/x86/gpt.o
+    OBJS += src/gpt.o
+    OBJS += src/x86/disk.o
     OBJS += src/x86/mptable.o
     OBJS += src/stage2_params.o
     OBJS += src/x86/exceptions.o

hal/mpfs250.c

@@ -41,6 +41,7 @@
 
 #include "printf.h"
 #include "loader.h"
+#include "disk.h"
 
 /* Placeholder functions - to be implemented */
 void hal_init(void)
@@ -124,6 +125,38 @@ void* hal_get_dts_address(void)
 }
 #endif
 
+/* TODO: Add support for reading uSD card with GPT (Global Partition Table) */
+/* The partition ID's are determined using BOOT_PART_A and BOOT_PART_B. */
+int disk_open(int drv)
+{
+    (void)drv;
+    return 0;
+}
+int disk_read(int drv, int part, uint64_t off, uint64_t sz, uint8_t *buf)
+{
+    (void)drv;
+    (void)part;
+    (void)off;
+    (void)sz;
+    (void)buf;
+    return 0;
+}
+int disk_write(int drv, int part, uint64_t off, uint64_t sz, const uint8_t *buf)
+{
+    (void)drv;
+    (void)part;
+    (void)off;
+    (void)sz;
+    (void)buf;
+    return 0;
+}
+int disk_find_partition_by_label(int drv, const char *label)
+{
+    (void)drv;
+    (void)label;
+    return 0;
+}
+
 #ifdef DEBUG_UART
 
 #ifndef DEBUG_UART_BASE

include/x86/gpt.h include/disk.hinclude/x86/gpt.h renamed to include/disk.h

@@ -1,4 +1,4 @@
-/* gpt.h
+/* disk.h
  *
  * Copyright (C) 2025 wolfSSL Inc.
  *
@@ -19,10 +19,15 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
  */
 
-#ifndef GPT_H
-#define GPT_H
+#ifndef _WOLFBOOT_DISK_H
+#define _WOLFBOOT_DISK_H
+
+#include <stdint.h>
+
 int disk_open(int drv);
 int disk_read(int drv, int part, uint64_t off, uint64_t sz, uint8_t *buf);
 int disk_write(int drv, int part, uint64_t off, uint64_t sz, const uint8_t *buf);
 int disk_find_partition_by_label(int drv, const char *label);
-#endif
+
+#endif /* _WOLFBOOT_DISK_H */
+

include/gpt.h

@@ -0,0 +1,154 @@
+/* gpt.h
+ *
+ * Generic GPT (GUID Partition Table) parsing support.
+ *
+ * Copyright (C) 2025 wolfSSL Inc.
+ *
+ * This file is part of wolfBoot.
+ *
+ * wolfBoot is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfBoot is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+#ifndef GPT_H
+#define GPT_H
+
+#include <stdint.h>
+
+/* GPT Constants */
+#define GPT_SECTOR_SIZE        0x200
+#define GPT_SIGNATURE          0x5452415020494645ULL /* "EFI PART" */
+#define GPT_PTYPE_PROTECTIVE   0xEE
+#define GPT_PART_NAME_SIZE     36
+#define GPT_MBR_ENTRY_START    0x01BE
+#define GPT_MBR_BOOTSIG_OFFSET 0x01FE
+#define GPT_MBR_BOOTSIG_VALUE  0xAA55
+
+/**
+ * @brief MBR partition table entry structure.
+ *
+ * This packed structure defines the layout of an MBR partition table entry
+ * used to identify GPT partitions (protective MBR).
+ */
+struct __attribute__((packed)) gpt_mbr_part_entry {
+    uint8_t stat;
+    uint8_t chs_first[3];
+    uint8_t ptype;
+    uint8_t chs_last[3];
+    uint32_t lba_first;
+    uint32_t lba_size;
+};
+
+/**
+ * @brief GPT (GUID Partition Table) header structure.
+ */
+struct __attribute__((packed)) guid_ptable {
+    uint64_t signature;
+    uint32_t revision;
+    uint32_t hdr_size;
+    uint32_t hdr_crc32;
+    uint32_t res0;
+    uint64_t main_lba;
+    uint64_t backup_lba;
+    uint64_t first_usable;
+    uint64_t last_usable;
+    uint64_t disk_guid[2];
+    uint64_t start_array;
+    uint32_t n_part;
+    uint32_t array_sz;
+    uint32_t part_crc;
+    uint8_t  res1[GPT_SECTOR_SIZE - 0x5C];
+};
+
+/**
+ * @brief GPT partition entry structure.
+ *
+ * This packed structure defines the layout of a GPT partition entry
+ * used to describe individual partitions on the disk.
+ */
+struct __attribute__((packed)) gpt_part_entry {
+    uint64_t type[2];
+    uint64_t uuid[2];
+    uint64_t first;
+    uint64_t last;
+    uint64_t flags;
+    uint16_t name[GPT_PART_NAME_SIZE];
+};
+
+/**
+ * @brief Parsed partition information.
+ *
+ * This structure holds parsed information about a partition extracted
+ * from a GPT partition entry.
+ */
+struct gpt_part_info {
+    uint64_t start;  /* Start offset in bytes */
+    uint64_t end;    /* End offset in bytes */
+    uint16_t name[GPT_PART_NAME_SIZE];
+};
+
+/**
+ * @brief Check MBR for protective GPT partition entry.
+ *
+ * Scans the MBR sector for a protective GPT partition entry (type 0xEE)
+ * and validates the boot signature.
+ *
+ * @param[in] mbr_sector Pointer to 512-byte MBR sector data.
+ * @param[out] gpt_lba If not NULL, receives the LBA of the GPT header.
+ *
+ * @return 0 on success (valid protective MBR found), -1 on error.
+ */
+int gpt_check_mbr_protective(const uint8_t *mbr_sector, uint32_t *gpt_lba);
+
+/**
+ * @brief Parse and validate a GPT header.
+ *
+ * Validates the GPT signature and copies header data to the output structure.
+ *
+ * @param[in] sector Pointer to 512-byte GPT header sector data.
+ * @param[out] hdr Pointer to structure to receive parsed header.
+ *
+ * @return 0 on success (valid GPT header), -1 on error.
+ */
+int gpt_parse_header(const uint8_t *sector, struct guid_ptable *hdr);
+
+/**
+ * @brief Parse a GPT partition entry.
+ *
+ * Parses a single partition entry and extracts partition information.
+ * Returns success only if the partition entry is valid (non-zero type GUID).
+ *
+ * @param[in] entry_data Pointer to partition entry data.
+ * @param[in] entry_size Size of the partition entry in bytes.
+ * @param[out] part Pointer to structure to receive parsed partition info.
+ *
+ * @return 0 on success (valid partition entry), -1 if entry is empty/invalid.
+ */
+int gpt_parse_partition(const uint8_t *entry_data, uint32_t entry_size,
+                        struct gpt_part_info *part);
+
+/**
+ * @brief Compare UTF-16 partition name with ASCII string.
+ *
+ * Compares a GPT partition name (UTF-16LE) with an ASCII string label.
+ *
+ * @param[in] utf16_name UTF-16LE partition name from GPT entry.
+ * @param[in] ascii_label ASCII string to compare against.
+ *
+ * @return 1 if names match, 0 if they don't match.
+ */
+int gpt_part_name_eq(const uint16_t *utf16_name, const char *ascii_label);
+
+#endif /* GPT_H */
+

include/x86/common.h

@@ -62,6 +62,7 @@ uint32_t io_read32(uint16_t port);
 void reset(uint8_t warm);
 void delay(int msec);
 void panic();
+#define wolfBoot_panic() panic()
 void cpuid(uint32_t eax_param,
            uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx);
 int cpuid_is_1gb_page_supported();