1 files changed, 140 insertions, 0 deletions
diff --git a/roms/edk2/OvmfPkg/OvmfXenElfHeaderGenerator.c b/roms/edk2/OvmfPkg/OvmfXenElfHeaderGenerator.c
new file mode 100644
index 000000000..90f0574fc
--- /dev/null
+++ b/roms/edk2/OvmfPkg/OvmfXenElfHeaderGenerator.c
@@ -0,0 +1,140 @@
+/** @file
+  This program generates a hex array to be manually coppied into
+  OvmfXen.fdf.
+
+  The purpose is for the flash device image to be recognize as an ELF.
+
+  Copyright (c) 2019, Citrix Systems, Inc.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include "elf.h"
+#include "stdio.h"
+#include "stddef.h"
+
+void print_hdr(void *s, size_t size)
+{
+  char *c = s;
+
+  while (size--) {
+    printf("0x%02hhx, ", *(c++));
+  }
+}
+
+/* Format for the XEN_ELFNOTE_PHYS32_ENTRY program segment */
+#define XEN_ELFNOTE_PHYS32_ENTRY 18
+typedef struct {
+  uint32_t name_size;
+  uint32_t desc_size;
+  uint32_t type;
+  char name[4];
+  uint32_t desc;
+} xen_elfnote_phys32_entry;
+
+int main(void)
+{
+  /* FW_SIZE */
+  size_t ovmf_blob_size = 0x00200000;
+  /* Load OVMF at 1MB when running as PVH guest */
+  uint32_t ovmf_base_address = 0x00100000;
+  /* Xen PVH entry point */
+  uint32_t ovmfxen_pvh_entry_point = ovmf_base_address + ovmf_blob_size - 0x30;
+  size_t offset_into_file = 0;
+
+  /* ELF file header */
+  Elf32_Ehdr hdr = {
+    .e_ident = ELFMAG,
+    .e_type = ET_EXEC,
+    .e_machine = EM_386,
+    .e_version = EV_CURRENT,
+    .e_entry = ovmfxen_pvh_entry_point,
+    .e_flags = R_386_NONE,
+    .e_ehsize = sizeof (hdr),
+    .e_phentsize = sizeof (Elf32_Phdr),
+  };
+  offset_into_file += sizeof (hdr);
+
+  hdr.e_ident[EI_CLASS] = ELFCLASS32;
+  hdr.e_ident[EI_DATA] = ELFDATA2LSB;
+  hdr.e_ident[EI_VERSION] = EV_CURRENT;
+  hdr.e_ident[EI_OSABI] = ELFOSABI_LINUX;
+  /* Placing program headers just after hdr */
+  hdr.e_phoff = sizeof (hdr);
+
+  /* program header */
+  Elf32_Phdr phdr_load = {
+    .p_type = PT_LOAD,
+    .p_offset = 0, /* load everything */
+    .p_paddr = ovmf_base_address,
+    .p_filesz = ovmf_blob_size,
+    .p_memsz = ovmf_blob_size,
+    .p_flags = PF_X | PF_W | PF_R,
+    .p_align = 0,
+  };
+  phdr_load.p_vaddr = phdr_load.p_paddr;
+  hdr.e_phnum += 1;
+  offset_into_file += sizeof (phdr_load);
+
+  /* Xen ELF Note. */
+
+  xen_elfnote_phys32_entry xen_elf_note = {
+    .type = XEN_ELFNOTE_PHYS32_ENTRY,
+    .name = "Xen",
+    .desc = ovmfxen_pvh_entry_point,
+    .name_size =
+      offsetof (xen_elfnote_phys32_entry, desc) -
+      offsetof (xen_elfnote_phys32_entry, name),
+    .desc_size =
+      sizeof (xen_elfnote_phys32_entry) -
+      offsetof (xen_elfnote_phys32_entry, desc),
+  };
+  Elf32_Phdr phdr_note = {
+    .p_type = PT_NOTE,
+    .p_filesz = sizeof (xen_elf_note),
+    .p_memsz = sizeof (xen_elf_note),
+    .p_flags = PF_R,
+    .p_align = 0,
+  };
+  hdr.e_phnum += 1;
+  offset_into_file += sizeof (phdr_note);
+  phdr_note.p_offset = offset_into_file;
+  phdr_note.p_paddr = ovmf_base_address + phdr_note.p_offset;
+  phdr_note.p_vaddr = phdr_note.p_paddr;
+
+
+  /*
+   * print elf header
+   */
+
+  size_t i;
+  size_t hdr_size = sizeof (hdr);
+  size_t entry_off = offsetof(typeof(hdr), e_entry);
+
+  printf("# ELF file header\n");
+  print_hdr(&hdr, entry_off);
+  printf("\n");
+  print_hdr(&hdr.e_entry, sizeof (hdr.e_entry));
+  printf(" # hdr.e_entry\n");
+  print_hdr(&hdr.e_entry + 1, hdr_size - entry_off - sizeof (hdr.e_entry));
+
+  printf("\n\n# ELF Program segment headers\n");
+  printf("# - Load segment\n");
+  for (i = 0; i < sizeof (phdr_load); i += 4) {
+    print_hdr(((char*)&phdr_load) + i, 4);
+    printf("\n");
+  }
+  printf("# - ELFNOTE segment\n");
+  for (i = 0; i < sizeof (phdr_note); i += 4) {
+    print_hdr(((char*)&phdr_note) + i, 4);
+    printf("\n");
+  }
+
+  printf("\n# XEN_ELFNOTE_PHYS32_ENTRY\n");
+  for (i = 0; i < sizeof (xen_elf_note); i += 4) {
+    print_hdr(((char*)&xen_elf_note) + i, 4);
+    printf("\n");
+  }
+
+  return 0;
+}