Fix building x86_64 xen platform

On Xen we do not have a separate boot section, we directly start at the
kernel map address.  We thus do not have a map shift.

3 files changed, 38 insertions, 46 deletions

diff --git a/x86_64/Makefrag.am b/x86_64/Makefrag.am
index 0139940a..edf533fd 100644
--- a/x86_64/Makefrag.am
+++ b/x86_64/Makefrag.am
@@ -211,28 +211,6 @@ nodist_libkernel_a_SOURCES += \
 # Architecture specialities.
 #
 
-if PLATFORM_at
-# This should probably be 0xffffffff80000000 for mcmodel=kernel, but let's try
-# to stay in the first 8G first, otherwise we have to fix the pmap module to
-# actually use the l4 page level
-#KERNEL_MAP_BASE=0x100000000
-# but for nor try with < 4G, otherwise we have linker errors
-KERNEL_MAP_BASE=0x40000000
-gnumach_LINKFLAGS += \
-	--defsym _START_MAP=$(_START_MAP) \
-	--defsym _START=_START_MAP \
-	--defsym KERNEL_MAP_BASE=$(KERNEL_MAP_BASE) \
-	-T '$(srcdir)'/x86_64/ldscript
-
-AM_CFLAGS += -D_START_MAP=$(_START_MAP) \
-	-DKERNEL_MAP_BASE=$(KERNEL_MAP_BASE)
-AM_CCASFLAGS += -D_START_MAP=$(_START_MAP) \
-	-DKERNEL_MAP_BASE=$(KERNEL_MAP_BASE)
-
-AM_CCASFLAGS += \
-	-Ii386
-endif
-
 AM_CPPFLAGS += \
 	-I$(top_srcdir)/i386 \
 	-I$(top_srcdir)/i386/i386 \
@@ -273,7 +251,26 @@ include_mach_x86_64_HEADERS = \
 # Platform specific parts.
 #
 
+if PLATFORM_at
+# This should probably be 0xffffffff80000000 for mcmodel=kernel, but let's try
+# to stay in the first 8G first, otherwise we have to fix the pmap module to
+# actually use the l4 page level
+#KERNEL_MAP_BASE=0x100000000
+# but for nor try with < 4G, otherwise we have linker errors
+KERNEL_MAP_BASE=0x40000000
+gnumach_LINKFLAGS += \
+	--defsym _START_MAP=$(_START_MAP) \
+	--defsym _START=$(_START_MAP) \
+	--defsym KERNEL_MAP_SHIFT=$(KERNEL_MAP_BASE) \
+	-T '$(srcdir)'/x86_64/ldscript
+
+AM_CCASFLAGS += \
+	-Ii386
+endif
+
 if PLATFORM_xen
+KERNEL_MAP_BASE=0x40000000
+
 libkernel_a_SOURCES += \
 	x86_64/xen_locore.S \
 	x86_64/xen_boothdr.S \
@@ -281,9 +278,15 @@ libkernel_a_SOURCES += \
 	i386/i386/xen.h
 
 gnumach_LINKFLAGS += \
-	--defsym _START=0x40000000 \
-	--defsym _START_MAP=0x40000000 \
+	--defsym _START_MAP=$(KERNEL_MAP_BASE) \
+	--defsym _START=$(KERNEL_MAP_BASE) \
+	--defsym KERNEL_MAP_SHIFT=0 \
 	-T '$(srcdir)'/x86_64/ldscript
 endif
+
+AM_CFLAGS += -D_START_MAP=$(_START_MAP) \
+	-DKERNEL_MAP_BASE=$(KERNEL_MAP_BASE)
+AM_CCASFLAGS += -D_START_MAP=$(_START_MAP) \
+	-DKERNEL_MAP_BASE=$(KERNEL_MAP_BASE)
 
 endif # HOST_x86_64
diff --git a/x86_64/boothdr.S b/x86_64/boothdr.S
index 5ea7834d..d81f9a78 100644
--- a/x86_64/boothdr.S
+++ b/x86_64/boothdr.S
@@ -26,8 +26,6 @@
 	 */
 	.section .boot.text,"ax"
 	/* We should never be entered this way.	 */
-	.globl	_start
-_start:
 	.globl	boot_start
 boot_start:
 
@@ -36,11 +34,7 @@ boot_start:
 
 	/* MultiBoot header - see multiboot.h.	*/
 #define	MULTIBOOT_MAGIC		0x1BADB002
-#ifdef __ELF__
 #define MULTIBOOT_FLAGS		0x00000003
-#else  /* __ELF__ */
-#define MULTIBOOT_FLAGS		0x00010003
-#endif /* __ELF__ */
 	P2ALIGN(2)
 boot_hdr:
 	.long	MULTIBOOT_MAGIC
@@ -50,14 +44,9 @@ boot_hdr:
 	* XX this works OK until we need at least the 30th bit.
 	*/
 	.long	- (MULTIBOOT_MAGIC+MULTIBOOT_FLAGS)
-#ifndef __ELF__	/* a.out kludge */
-	.long	boot_hdr	/* header_addr */
-	.long	_start		/* load_addr */
-	.long	_edata		/* load_end_addr */
-	.long	_end		/* bss_end_addr */
-	.long	boot_entry	/* entry */
-#endif /* __ELF__ */
 
+	.global _start
+_start:
 boot_entry:
 	/*
 	 * Prepare minimal page mapping to jump to 64 bit and to C code.
diff --git a/x86_64/ldscript b/x86_64/ldscript
index de99795e..67703b4d 100644
--- a/x86_64/ldscript
+++ b/x86_64/ldscript
@@ -12,16 +12,16 @@ SECTIONS
    * `gnumach_LINKFLAGS' in `i386/Makefrag.am'.
    */
 
-  . = _START_MAP;
-  .boot           :
+  . = _START;
+  .boot           : AT(_START_MAP)
   {
     *(.boot.text)
     *(.boot.data)
   } =0x90909090
 
-  . += KERNEL_MAP_BASE;
+  . += KERNEL_MAP_SHIFT;
   _start = .;
-  .text           : AT(((ADDR(.text)) - KERNEL_MAP_BASE))
+  .text           : AT(((ADDR(.text)) - KERNEL_MAP_SHIFT))
   {
     *(.text*)
     *(.text .stub .text.* .gnu.linkonce.t.*)
@@ -30,11 +30,11 @@ SECTIONS
     /* .gnu.warning sections are handled specially by elf32.em.  */
     *(.gnu.warning)
   } =0x90909090
-  .init           : AT(((ADDR(.init)) - KERNEL_MAP_BASE))
+  .init           : AT(((ADDR(.init)) - KERNEL_MAP_SHIFT))
   {
     KEEP (*(.init))
   } =0x90909090
-  .fini           : AT(((ADDR(.fini)) - KERNEL_MAP_BASE))
+  .fini           : AT(((ADDR(.fini)) - KERNEL_MAP_SHIFT))
   {
     KEEP (*(.fini))
   } =0x90909090
@@ -77,7 +77,7 @@ SECTIONS
       PROVIDE_HIDDEN (__rela_iplt_end = .);
     }
   .plt            : { *(.plt) *(.iplt) }
-  .rodata         :  AT(((ADDR(.rodata)) - KERNEL_MAP_BASE)) { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+  .rodata         :  AT(((ADDR(.rodata)) - KERNEL_MAP_SHIFT)) { *(.rodata .rodata.* .gnu.linkonce.r.*) }
   .rodata1        : { *(.rodata1) }
   .eh_frame_hdr : { *(.eh_frame_hdr) }
   .eh_frame       : ONLY_IF_RO { KEEP (*(.eh_frame)) }
@@ -147,7 +147,7 @@ SECTIONS
   .got            : { *(.got) *(.igot) }
   . = DATA_SEGMENT_RELRO_END (24, .);
   .got.plt        : { *(.got.plt)  *(.igot.plt) }
-  .data           : AT(((ADDR(.data)) - KERNEL_MAP_BASE))
+  .data           : AT(((ADDR(.data)) - KERNEL_MAP_SHIFT))
   {
     *(.data .data.* .gnu.linkonce.d.*)
     SORT(CONSTRUCTORS)
@@ -155,7 +155,7 @@ SECTIONS
   .data1          : { *(.data1) }
   _edata = .; PROVIDE (edata = .);
   __bss_start = .;
-  .bss            : AT(((ADDR(.bss)) - KERNEL_MAP_BASE))
+  .bss            : AT(((ADDR(.bss)) - KERNEL_MAP_SHIFT))
   {
    *(.dynbss)
    *(.bss .bss.* .gnu.linkonce.b.*)