[PATCH v1.1 2/3] x86/build: Don't convert boot/{cmdline,head}.bin back to .S

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

There's no point wasting time converting binaries back to asm source.  Just
use .incbin directly.  Explain in head.S what these binaries are.

Also, align the blobs.  While there's very little static data in the blobs,
they should have at least 4 byte alignment.  There was previously no guarantee
that cmdline_parse_early was aligned, and there is no longer an implicit
4-byte alignment between cmdline_parse_early and reloc caused by the use of
.long.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <JBeulich@xxxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Wei Liu <wl@xxxxxxx>
CC: Anthony PERARD <anthony.perard@xxxxxxxxxx>

v1.1:
 * Rebase over the out-of-tree build work

Cleanup to $(head-srcs) deferred to the subsequent patch to make the change
legible.
---
 xen/arch/x86/boot/Makefile |  9 ++++-----
 xen/arch/x86/boot/head.S   | 10 ++++++++--
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/xen/arch/x86/boot/Makefile b/xen/arch/x86/boot/Makefile
index a5dd094836f6..0670e03b72e0 100644
--- a/xen/arch/x86/boot/Makefile
+++ b/xen/arch/x86/boot/Makefile
@@ -10,7 +10,10 @@ head-srcs := $(addprefix $(obj)/, $(head-srcs))
 ifdef building_out_of_srctree
 $(obj)/head.o: CFLAGS-y += -iquote $(obj)
 endif
-$(obj)/head.o: $(head-srcs)
+# For .incbin - add $(obj) to the include path and add the dependencies
+# manually as they're not included in .d
+$(obj)/head.o: AFLAGS-y += -Wa$(comma)-I$(obj)
+$(obj)/head.o: $(head-srcs:.S=.bin)
 
 CFLAGS_x86_32 := $(subst -m64,-m32 -march=i686,$(XEN_TREEWIDE_CFLAGS))
 $(call cc-options-add,CFLAGS_x86_32,CC,$(EMBEDDED_EXTRA_CFLAGS))
@@ -24,10 +27,6 @@ CFLAGS_x86_32 += -I$(srctree)/include
 $(head-srcs:.S=.o): CFLAGS_stack_boundary :=
 $(head-srcs:.S=.o): XEN_CFLAGS := $(CFLAGS_x86_32) -fpic
 
-$(head-srcs): %.S: %.bin
-       (od -v -t x $< | tr -s ' ' | awk 'NR > 1 {print s} {s=$$0}' | \
-       sed 's/ /,0x/g' | sed 's/,0x$$//' | sed 's/^[0-9]*,/ .long /') >$@
-
 %.bin: %.lnk
        $(OBJCOPY) -j .text -O binary $< $@
 
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 3db47197b841..0fb7dd3029f2 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -777,11 +777,17 @@ trampoline_setup:
         /* Jump into the relocated trampoline. */
         lret
 
+        /*
+         * cmdline and reloc are written in C, and linked to be 32bit PIC with
+         * entrypoints at 0 and using the stdcall convention.
+         */
+        ALIGN
 cmdline_parse_early:
-#include "cmdline.S"
+        .incbin "cmdline.bin"
 
+        ALIGN
 reloc:
-#include "reloc.S"
+        .incbin "reloc.bin"
 
 ENTRY(trampoline_start)
 #include "trampoline.S"
-- 
2.11.0