1 files changed, 118 insertions, 0 deletions
diff --git a/qemu/tests/boot-sector.c b/qemu/tests/boot-sector.c
new file mode 100644
index 000000000..3ffe2987f
--- /dev/null
+++ b/qemu/tests/boot-sector.c
@@ -0,0 +1,118 @@
+/*
+ * QEMU boot sector testing helpers.
+ *
+ * Copyright (c) 2016 Red Hat Inc.
+ *
+ * Authors:
+ *  Michael S. Tsirkin <mst@redhat.com>
+ *  Victor Kaplansky <victork@redhat.com>    
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "boot-sector.h"
+#include "qemu-common.h"
+#include "libqtest.h"
+
+#define LOW(x) ((x) & 0xff)
+#define HIGH(x) ((x) >> 8)
+
+#define SIGNATURE 0xdead
+#define SIGNATURE_OFFSET 0x10
+#define BOOT_SECTOR_ADDRESS 0x7c00
+
+/* Boot sector code: write SIGNATURE into memory,
+ * then halt.
+ * Q35 machine requires a minimum 0x7e000 bytes disk.
+ * (bug or feature?)
+ */
+static uint8_t boot_sector[0x7e000] = {
+    /* The first sector will be placed at RAM address 00007C00, and
+     * the BIOS transfers control to 00007C00
+     */
+
+    /* Data Segment register should be initialized, since pxe
+     * boot loader can leave it dirty.
+     */
+
+    /* 7c00: move $0000,%ax */
+    [0x00] = 0xb8,
+    [0x01] = 0x00,
+    [0x02] = 0x00,
+    /* 7c03: move %ax,%ds */
+    [0x03] = 0x8e,
+    [0x04] = 0xd8,
+
+    /* 7c05: mov $0xdead,%ax */
+    [0x05] = 0xb8,
+    [0x06] = LOW(SIGNATURE),
+    [0x07] = HIGH(SIGNATURE),
+    /* 7c08:  mov %ax,0x7c10 */
+    [0x08] = 0xa3,
+    [0x09] = LOW(BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET),
+    [0x0a] = HIGH(BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET),
+
+    /* 7c0b cli */
+    [0x0b] = 0xfa,
+    /* 7c0c: hlt */
+    [0x0c] = 0xf4,
+    /* 7c0e: jmp 0x7c07=0x7c0f-3 */
+    [0x0d] = 0xeb,
+    [0x0e] = LOW(-3),
+    /* We mov 0xdead here: set value to make debugging easier */
+    [SIGNATURE_OFFSET] = LOW(0xface),
+    [SIGNATURE_OFFSET + 1] = HIGH(0xface),
+    /* End of boot sector marker */
+    [0x1FE] = 0x55,
+    [0x1FF] = 0xAA,
+};
+
+/* Create boot disk file.  */
+int boot_sector_init(const char *fname)
+{
+    FILE *f = fopen(fname, "w");
+
+    if (!f) {
+        fprintf(stderr, "Couldn't open \"%s\": %s", fname, strerror(errno));
+        return 1;
+    }
+    fwrite(boot_sector, 1, sizeof boot_sector, f);
+    fclose(f);
+    return 0;
+}
+
+/* Loop until signature in memory is OK.  */
+void boot_sector_test(void)
+{
+    uint8_t signature_low;
+    uint8_t signature_high;
+    uint16_t signature;
+    int i;
+
+   /* Wait at most 1 minute */
+#define TEST_DELAY (1 * G_USEC_PER_SEC / 10)
+#define TEST_CYCLES MAX((60 * G_USEC_PER_SEC / TEST_DELAY), 1)
+
+    /* Poll until code has run and modified memory.  Once it has we know BIOS
+     * initialization is done.  TODO: check that IP reached the halt
+     * instruction.
+     */
+    for (i = 0; i < TEST_CYCLES; ++i) {
+        signature_low = readb(BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET);
+        signature_high = readb(BOOT_SECTOR_ADDRESS + SIGNATURE_OFFSET + 1);
+        signature = (signature_high << 8) | signature_low;
+        if (signature == SIGNATURE) {
+            break;
+        }
+        g_usleep(TEST_DELAY);
+    }
+
+    g_assert_cmphex(signature, ==, SIGNATURE);
+}
+
+/* unlink boot disk file.  */
+void boot_sector_cleanup(const char *fname)
+{
+    unlink(fname);
+}