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-rw-r--r--tests/migration/i386/a-b-bootblock.S88
1 files changed, 88 insertions, 0 deletions
diff --git a/tests/migration/i386/a-b-bootblock.S b/tests/migration/i386/a-b-bootblock.S
new file mode 100644
index 0000000000..3f97f28023
--- /dev/null
+++ b/tests/migration/i386/a-b-bootblock.S
@@ -0,0 +1,88 @@
+# x86 bootblock used in migration test
+#  repeatedly increments the first byte of each page in a 100MB
+#  range.
+#  Outputs an initial 'A' on serial followed by repeated 'B's
+#
+# Copyright (c) 2016 Red Hat, Inc. and/or its affiliates
+# This work is licensed under the terms of the GNU GPL, version 2 or later.
+# See the COPYING file in the top-level directory.
+#
+# Author: dgilbert@redhat.com
+
+
+.code16
+.org 0x7c00
+        .file   "fill.s"
+        .text
+        .globl  start
+        .type   start, @function
+start:             # at 0x7c00 ?
+        cli
+        lgdt gdtdesc
+        mov $1,%eax
+        mov %eax,%cr0  # Protected mode enable
+        data32 ljmp $8,$0x7c20
+
+.org 0x7c20
+.code32
+        # A20 enable - not sure I actually need this
+        inb $0x92,%al
+        or  $2,%al
+        outb %al, $0x92
+
+        # set up DS for the whole of RAM (needed on KVM)
+        mov $16,%eax
+        mov %eax,%ds
+
+        mov $65,%ax
+        mov $0x3f8,%dx
+        outb %al,%dx
+
+        # bl keeps a counter so we limit the output speed
+        mov $0, %bl
+mainloop:
+        # Start from 1MB
+        mov $(1024*1024),%eax
+innerloop:
+        incb (%eax)
+        add $4096,%eax
+        cmp $(100*1024*1024),%eax
+        jl innerloop
+
+        inc %bl
+        jnz mainloop
+
+        mov $66,%ax
+        mov $0x3f8,%dx
+        outb %al,%dx
+
+        jmp mainloop
+
+        # GDT magic from old (GPLv2)  Grub startup.S
+        .p2align        2       /* force 4-byte alignment */
+gdt:
+        .word   0, 0
+        .byte   0, 0, 0, 0
+
+        /* -- code segment --
+         * base = 0x00000000, limit = 0xFFFFF (4 KiB Granularity), present
+         * type = 32bit code execute/read, DPL = 0
+         */
+        .word   0xFFFF, 0
+        .byte   0, 0x9A, 0xCF, 0
+
+        /* -- data segment --
+         * base = 0x00000000, limit 0xFFFFF (4 KiB Granularity), present
+         * type = 32 bit data read/write, DPL = 0
+         */
+        .word   0xFFFF, 0
+        .byte   0, 0x92, 0xCF, 0
+
+gdtdesc:
+        .word   0x27                    /* limit */
+        .long   gdt                     /* addr */
+
+/* I'm a bootable disk */
+.org 0x7dfe
+        .byte 0x55
+        .byte 0xAA