--- /dev/null
+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program 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 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+#include <realmode.h>
+#include <sdi.h>
+#include <ipxe/image.h>
+#include <ipxe/features.h>
+
+/** @file
+ *
+ * System Deployment Image (SDI)
+ *
+ * Based on the MSDN article "RAM boot using SDI in Windows XP
+ * Embedded with Service Pack 1", available at the time of writing
+ * from:
+ *
+ * http://msdn.microsoft.com/en-us/library/ms838543.aspx
+ */
+
+FEATURE ( FEATURE_IMAGE, "SDI", DHCP_EB_FEATURE_SDI, 1 );
+
+/**
+ * Parse SDI image header
+ *
+ * @v image SDI file
+ * @v sdi SDI header to fill in
+ * @ret rc Return status code
+ */
+static int sdi_parse_header ( struct image *image, struct sdi_header *sdi ) {
+
+ /* Sanity check */
+ if ( image->len < sizeof ( *sdi ) ) {
+ DBGC ( image, "SDI %p too short for SDI header\n", image );
+ return -ENOEXEC;
+ }
+
+ /* Read in header */
+ copy_from_user ( sdi, image->data, 0, sizeof ( *sdi ) );
+
+ /* Check signature */
+ if ( sdi->magic != SDI_MAGIC ) {
+ DBGC ( image, "SDI %p is not an SDI image\n", image );
+ return -ENOEXEC;
+ }
+
+ return 0;
+}
+
+/**
+ * Execute SDI image
+ *
+ * @v image SDI file
+ * @ret rc Return status code
+ */
+static int sdi_exec ( struct image *image ) {
+ struct sdi_header sdi;
+ uint32_t sdiptr;
+ int rc;
+
+ /* Parse image header */
+ if ( ( rc = sdi_parse_header ( image, &sdi ) ) != 0 )
+ return rc;
+
+ /* Check that image is bootable */
+ if ( sdi.boot_size == 0 ) {
+ DBGC ( image, "SDI %p is not bootable\n", image );
+ return -ENOTTY;
+ }
+ DBGC ( image, "SDI %p image at %08lx+%08zx\n",
+ image, user_to_phys ( image->data, 0 ), image->len );
+ DBGC ( image, "SDI %p boot code at %08lx+%llx\n", image,
+ user_to_phys ( image->data, sdi.boot_offset ), sdi.boot_size );
+
+ /* Copy boot code */
+ memcpy_user ( real_to_user ( SDI_BOOT_SEG, SDI_BOOT_OFF ), 0,
+ image->data, sdi.boot_offset, sdi.boot_size );
+
+ /* Jump to boot code */
+ sdiptr = ( user_to_phys ( image->data, 0 ) | SDI_WTF );
+ __asm__ __volatile__ ( REAL_CODE ( "ljmp %0, %1\n\t" )
+ : : "i" ( SDI_BOOT_SEG ),
+ "i" ( SDI_BOOT_OFF ),
+ "d" ( sdiptr ) );
+
+ /* There is no way for the image to return, since we provide
+ * no return address.
+ */
+ assert ( 0 );
+
+ return -ECANCELED; /* -EIMPOSSIBLE */
+}
+
+/**
+ * Probe SDI image
+ *
+ * @v image SDI file
+ * @ret rc Return status code
+ */
+static int sdi_probe ( struct image *image ) {
+ struct sdi_header sdi;
+ int rc;
+
+ /* Parse image */
+ if ( ( rc = sdi_parse_header ( image, &sdi ) ) != 0 )
+ return rc;
+
+ return 0;
+}
+
+/** SDI image type */
+struct image_type sdi_image_type __image_type ( PROBE_NORMAL ) = {
+ .name = "SDI",
+ .probe = sdi_probe,
+ .exec = sdi_exec,
+};
projects / thirdparty / ipxe.git / commitdiff
