diff --git a/docs/grub.texi b/docs/grub.texi
index 54a2d8791..d9500fb52 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -3305,6 +3305,7 @@ X86 support is summarised in the following table. ``Yes'' means that the kernel
@item @tab BIOS @tab Coreboot
@item BIOS chainloading @tab yes @tab no (1)
@item NTLDR @tab yes @tab no (1)
+@item Freedos @tab yes @tab no (1)
@item FreeBSD bootloader @tab yes @tab crashes (1)
@item 32-bit kFreeBSD @tab yes @tab crashes (2,6)
@item 64-bit kFreeBSD @tab yes @tab crashes (2,6)
@@ -3329,6 +3330,7 @@ X86 support is summarised in the following table. ``Yes'' means that the kernel
@item @tab Multiboot @tab Qemu
@item BIOS chainloading @tab no (1) @tab no (1)
@item NTLDR @tab no (1) @tab no (1)
+@item FreeDOS @tab no (1) @tab no (1)
@item FreeBSD bootloader @tab crashes (1) @tab crashes (1)
@item 32-bit kFreeBSD @tab crashes (6) @tab crashes (6)
@item 64-bit kFreeBSD @tab crashes (6) @tab crashes (6)
@@ -3353,6 +3355,7 @@ X86 support is summarised in the following table. ``Yes'' means that the kernel
@item @tab 32-bit EFI @tab 64-bit EFI
@item BIOS chainloading @tab no (1) @tab no (1)
@item NTLDR @tab no (1) @tab no (1)
+@item FreeDOS @tab no (1) @tab no (1)
@item FreeBSD bootloader @tab crashes (1) @tab crashes (1)
@item 32-bit kFreeBSD @tab headless @tab headless
@item 64-bit kFreeBSD @tab headless @tab headless
@@ -3377,6 +3380,7 @@ X86 support is summarised in the following table. ``Yes'' means that the kernel
@item @tab IEEE1275
@item BIOS chainloading @tab no (1)
@item NTLDR @tab no (1)
+@item FreeDOS @tab no (1)
@item FreeBSD bootloader @tab crashes (1)
@item 32-bit kFreeBSD @tab crashes (6)
@item 64-bit kFreeBSD @tab crashes (6)
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 37c0ce970..da309d6d9 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -1158,6 +1158,12 @@ module = {
enable = i386_pc;
};
+module = {
+ name = freedos;
+ i386_pc = loader/i386/pc/freedos.c;
+ enable = i386_pc;
+};
+
module = {
name = multiboot2;
cppflags = "-DGRUB_USE_MULTIBOOT2";
diff --git a/grub-core/lib/i386/relocator.c b/grub-core/lib/i386/relocator.c
index 1bc4240c3..2f10feb5e 100644
--- a/grub-core/lib/i386/relocator.c
+++ b/grub-core/lib/i386/relocator.c
@@ -50,6 +50,7 @@ extern grub_uint16_t grub_relocator16_gs;
extern grub_uint16_t grub_relocator16_ss;
extern grub_uint16_t grub_relocator16_sp;
extern grub_uint32_t grub_relocator16_edx;
+extern grub_uint32_t grub_relocator16_ebx;
extern grub_uint8_t grub_relocator32_start;
extern grub_uint8_t grub_relocator32_end;
@@ -212,6 +213,7 @@ grub_relocator16_boot (struct grub_relocator *rel,
grub_relocator16_ss = state.ss;
grub_relocator16_sp = state.sp;
+ grub_relocator16_ebx = state.ebx;
grub_relocator16_edx = state.edx;
grub_memmove (get_virtual_current_address (ch), &grub_relocator16_start,
diff --git a/grub-core/lib/i386/relocator16.S b/grub-core/lib/i386/relocator16.S
index c3768f4eb..c6d38eba4 100644
--- a/grub-core/lib/i386/relocator16.S
+++ b/grub-core/lib/i386/relocator16.S
@@ -136,7 +136,12 @@ VARIABLE(grub_relocator16_sp)
.byte 0x66, 0xba
VARIABLE(grub_relocator16_edx)
.long 0
-
+
+ /* movw imm32, %ebx. */
+ .byte 0x66, 0xbb
+VARIABLE(grub_relocator16_ebx)
+ .long 0
+
/* Cleared direction flag is of no problem with any current
payload and makes this implementation easier. */
cld
diff --git a/grub-core/loader/i386/pc/freedos.c b/grub-core/loader/i386/pc/freedos.c
new file mode 100644
index 000000000..67d97e246
--- /dev/null
+++ b/grub-core/loader/i386/pc/freedos.c
@@ -0,0 +1,136 @@
+/* chainloader.c - boot another boot loader */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2002,2004,2007,2009,2010 Free Software Foundation, Inc.
+ *
+ * GRUB 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.
+ *
+ * GRUB 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 GRUB. If not, see .
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+static grub_dl_t my_mod;
+static struct grub_relocator *rel;
+static grub_uint32_t ebx = 0xffffffff;
+
+#define GRUB_FREEDOS_SEGMENT 0x60
+#define GRUB_FREEDOS_STACK_SEGMENT 0x1fe0
+#define GRUB_FREEDOS_STACK_POINTER 0x8000
+
+static grub_err_t
+grub_freedos_boot (void)
+{
+ struct grub_relocator16_state state = {
+ .cs = GRUB_FREEDOS_SEGMENT,
+ .ip = 0,
+ .ds = 0,
+ .es = 0,
+ .fs = 0,
+ .gs = 0,
+ .ss = GRUB_FREEDOS_STACK_SEGMENT,
+ .sp = GRUB_FREEDOS_STACK_POINTER,
+ .ebx = ebx,
+ .edx = 0
+ };
+ grub_video_set_mode ("text", 0, 0);
+
+ return grub_relocator16_boot (rel, state);
+}
+
+static grub_err_t
+grub_freedos_unload (void)
+{
+ grub_relocator_unload (rel);
+ rel = NULL;
+ grub_dl_unref (my_mod);
+ return GRUB_ERR_NONE;
+}
+
+static grub_err_t
+grub_cmd_freedos (grub_command_t cmd __attribute__ ((unused)),
+ int argc, char *argv[])
+{
+ grub_file_t file = 0;
+ grub_err_t err;
+ void *kernelsys;
+ grub_size_t kernelsyssize;
+
+ if (argc == 0)
+ return grub_error (GRUB_ERR_BAD_ARGUMENT, "no file specified");
+
+ grub_dl_ref (my_mod);
+
+ rel = grub_relocator_new ();
+ if (!rel)
+ goto fail;
+
+ file = grub_file_open (argv[0]);
+ if (! file)
+ goto fail;
+
+ ebx = grub_get_root_biosnumber ();
+
+ kernelsyssize = grub_file_size (file);
+ {
+ grub_relocator_chunk_t ch;
+ err = grub_relocator_alloc_chunk_addr (rel, &ch, GRUB_NTLDR_SEGMENT << 4,
+ kernelsyssize);
+ if (err)
+ goto fail;
+ kernelsys = get_virtual_current_address (ch);
+ }
+
+ if (grub_file_read (file, kernelsys, kernelsyssize)
+ != (grub_ssize_t) ntldrsize)
+ goto fail;
+
+ grub_loader_set (grub_freedos_boot, grub_freedos_unload, 1);
+ return GRUB_ERR_NONE;
+
+ fail:
+
+ if (file)
+ grub_file_close (file);
+
+ grub_ntldr_unload ();
+
+ return grub_errno;
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(freedos)
+{
+ cmd = grub_register_command ("freedos", grub_cmd_freedos,
+ 0, N_("Load FreeDOS kernel.sys."));
+ my_mod = mod;
+}
+
+GRUB_MOD_FINI(freedos)
+{
+ grub_unregister_command (cmd);
+}
diff --git a/include/grub/i386/relocator.h b/include/grub/i386/relocator.h
index 6ff5c6631..778049eef 100644
--- a/include/grub/i386/relocator.h
+++ b/include/grub/i386/relocator.h
@@ -46,6 +46,7 @@ struct grub_relocator16_state
grub_uint16_t ss;
grub_uint16_t sp;
grub_uint16_t ip;
+ grub_uint32_t ebx;
grub_uint32_t edx;
};