Update code and instructions to default to using USB disk image files

Makefile

@@ -12,15 +12,15 @@ all:    list_laptops
 
 list_laptops:
 	$(info )
-	$(info The following laptop make targets are supported:)
+	$(info The following make targets are the supported usb images:)
 	$(info )
-	$(info patched.t430.iso  - for patching Thinkpad T430)
-	$(info patched.t430s.iso - for patching Thinkpad T430s)
-	$(info patched.t530.iso  - for patching Thinkpad T530)
-	$(info patched.t530i.iso - for patching Thinkpad T530i)
-	$(info patched.w530.iso  - for patching Thinkpad W430)
-	$(info patched.x230.iso  - for patching Thinkpad X230)
-	$(info patched.x230t.iso - for patching Thinkpad X230t)
+	$(info patched.t430.img  - for patching Thinkpad T430)
+	$(info patched.t430s.img - for patching Thinkpad T430s)
+	$(info patched.t530.img  - for patching Thinkpad T530)
+	$(info patched.t530i.img - for patching Thinkpad T530i)
+	$(info patched.w530.img  - for patching Thinkpad W430)
+	$(info patched.x230.img  - for patching Thinkpad X230)
+	$(info patched.x230t.img - for patching Thinkpad X230t)
 	$(info )
 
 .PHONY: list_laptops
@@ -165,6 +165,25 @@ $(DEPSDIR)/slice.insert.deps: Makefile
 %.dosflash.exe.orig: %.iso.orig
 	MTOOLS_SKIP_CHECK=1 mcopy -i $^@@$(FAT_OFFSET) ::FLASH/DOSFLASH.EXE $@
 
+## Use the system provided geteltorito script, if there is one
+#GETELTORITO := $(shell if type geteltorito >/dev/null; then echo geteltorito; else echo ./geteltorito; fi)
+
+# use the included geteltorito script always, since we know it does not have
+# the hdd size bug
+GETELTORITO := ./geteltorito
+
+# extract the DOS boot image from an iso (and fix it up so qemu can boot it)
+%.img: %.iso
+	$(GETELTORITO) -o $@ $<
+	./hexpatch.pl $@ fix-hdd-image.patch
+
+# simple testing of images in an emulator
+%.iso.test: %.iso
+	qemu-system-x86_64 -enable-kvm -cdrom $<
+
+%.img.test: %.img
+	qemu-system-x86_64 -enable-kvm -hda $<
+
 mec-tools/Makefile:
 	git submodule update --init --remote
 

README

@@ -31,35 +31,43 @@ This software expects to be run under Linux.
 
     cd thinkpad-ec
 
-5. Show the list of laptops and ISO image names:
+5. Show the list of laptops and USB image file names:
 
     make list_laptops
 
-   (note that this list might change from time to time if there are new
-   BIOS versions released)
-
-6. Select the correct ISO name for your laptop.  E.G. "patched.x230.iso" for
+6. Select the correct IMG name for your laptop.  E.G. "patched.x230.img" for
    the x230 laptop.
 
-7. Create the patched ISO for this laptop (this will download the original
-   file from Lenovo and patch it):
+7. Make the fully patched iimage for this laptop (this will download
+   the original file from Lenovo and patch it):
 
-    make patched.x230.iso
+    make patched.x230.img
 
-8. Use your normal CDROM burning tools to put this image on a blank cd and
-   boot it up.  You will be prompted with information about the patch and
-   asked to confirm your laptop type.  Then it will automatically flash
-   the patched firmware.
+8. Insert your USB stick and determine what device name it has.
+   This command should help you find the right device:
 
+    lsblk -d -p -o NAME,SIZE,LABEL
 
-Notes:
+9. Write the bootable patched image onto the USB stick device
+
+   WARNING: if you do not have the right device name, you might overwrite
+   your hard drive!
+
+   sudo dd if=patched.x230.img of=/dev/sdb
 
-* These thinkpads will boot from a USB cdrom drive, so you do not need one
-  internal to your laptop for this to work.
+Your USB stick is now ready to boot and install the patched firmware.
+
+When you boot this, you will be prompted with information about the patch
+and asked to confirm your laptop type.  It will then automatically flash
+the patched firmware.
+
+
+Notes:
 
-* If you do not have a cdrom, or do not want to use it, it is possible to
-  extract an image from the ISO that is suitable for placing on a bootable
-  USB stick (I hope to add this as an automated feature shortly)
+* You can also create a bootable CDROM image for burning to a disk
+  by asking for a ".iso" file in step 7 above.  Then you can use your
+  normal CDROM burning tools to put this image on a blank cd and boot
+  it up, skipping steps 8 and 9.
 
 * More information for hacking on this can be found in the docs/HACKING.txt
   file.

fix-hdd-image.patch

@@ -0,0 +1,16 @@
+Qemu does not support disk images with more than 16 heads, but the lenovo
+disk image is created with 64 heads.  Since the MBR they used does not use
+LBA to access the disk, this confuses it and causes it to fail.
+
+This patch changes the partition end head/cylinder, which is all that is
+needed to make the MBR happy
+
+@@ fix partition table @@
+ 00000190  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 000001a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 000001b0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 80 01  |................|
+-000001c0  01 00 04 3f 20 1f 20 00  00 00 e0 ff 00 00 00 00  |...? . .........|
++000001c0  01 00 04 0f 20 7f 20 00  00 00 e0 ff 00 00 00 00  |.... . .........|
+ 000001d0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 000001e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 000001f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 55 aa  |..............U.|