Commit MD parts of a loosely functional AMD64 port. This is based on

a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from.  There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code.  pmap uses
  a variation of the PAE code in order to avoid having to worry about 4
  levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
  i386 loader.  This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
  not been translated yet, and some that I cheated and wrote dumb C
  versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
  passing, as is native on the amd64 ABI), and the 'syscall' instruction
  for syscalls.  int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
  of places (eg: to find which register they use to replace the trashed
  %rcx register in the syscall instruction).  As a result, there is not a
  lot of similarity.  I did look at NetBSD a few times while debugging to
  get some ideas about what I might have done wrong in my first attempt.

1 files changed, 27 insertions, 22 deletions

diff --git a/sys/amd64/include/elf.h b/sys/amd64/include/elf.h
index 46d512c..3883d49 100644
--- a/sys/amd64/include/elf.h
+++ b/sys/amd64/include/elf.h
@@ -30,17 +30,17 @@
 #define	_MACHINE_ELF_H_ 1
 
 /*
- * ELF definitions for the i386 architecture.
+ * ELF definitions for the AMD64 architecture.
  */
 
-#include <sys/elf32.h>	/* Definitions common to all 32 bit architectures. */
+#include <sys/elf64.h>	/* Definitions common to all 64 bit architectures. */
 
-#define	__ELF_WORD_SIZE	32	/* Used by <sys/elf_generic.h> */
+#define	__ELF_WORD_SIZE	64	/* Used by <sys/elf_generic.h> */
 #include <sys/elf_generic.h>
 
-#define	ELF_ARCH	EM_386
+#define	ELF_ARCH	EM_X86_64
 
-#define	ELF_MACHINE_OK(x) ((x) == EM_386 || (x) == EM_486)
+#define	ELF_MACHINE_OK(x) ((x) == EM_X86_64)
 
 /*
  * Auxiliary vector entries for passing information to the interpreter.
@@ -50,13 +50,13 @@
  */
 
 typedef struct {	/* Auxiliary vector entry on initial stack */
-	int	a_type;			/* Entry type. */
+	long	a_type;			/* Entry type. */
 	union {
 		long	a_val;		/* Integer value. */
 		void	*a_ptr;		/* Address. */
 		void	(*a_fcn)(void);	/* Function pointer (not used). */
 	} a_un;
-} Elf32_Auxinfo;
+} Elf64_Auxinfo;
 
 __ElfType(Auxinfo);
 
@@ -98,24 +98,29 @@ __ElfType(Auxinfo);
  * Relocation types.
  */
 
-#define	R_386_NONE	0	/* No relocation. */
-#define	R_386_32	1	/* Add symbol value. */
-#define	R_386_PC32	2	/* Add PC-relative symbol value. */
-#define	R_386_GOT32	3	/* Add PC-relative GOT offset. */
-#define	R_386_PLT32	4	/* Add PC-relative PLT offset. */
-#define	R_386_COPY	5	/* Copy data from shared object. */
-#define	R_386_GLOB_DAT	6	/* Set GOT entry to data address. */
-#define	R_386_JMP_SLOT	7	/* Set GOT entry to code address. */
-#define	R_386_RELATIVE	8	/* Add load address of shared object. */
-#define	R_386_GOTOFF	9	/* Add GOT-relative symbol address. */
-#define	R_386_GOTPC	10	/* Add PC-relative GOT table address. */
-
-#define	R_386_COUNT	11	/* Count of defined relocation types. */
+#define	R_X86_64_NONE	0	/* No relocation. */
+#define	R_X86_64_64	1	/* Add 64 bit symbol value. */
+#define	R_X86_64_PC32	2	/* PC-relative 32 bit signed sym value. */
+#define	R_X86_64_GOT32	3	/* PC-relative 32 bit GOT offset. */
+#define	R_X86_64_PLT32	4	/* PC-relative 32 bit PLT offset. */
+#define	R_X86_64_COPY	5	/* Copy data from shared object. */
+#define	R_X86_64_GLOB_DAT 6	/* Set GOT entry to data address. */
+#define	R_X86_64_JMP_SLOT 7	/* Set GOT entry to code address. */
+#define	R_X86_64_RELATIVE 8	/* Add load address of shared object. */
+#define	R_X86_64_GOTPCREL 9	/* Add 32 bit signed pcrel offset to GOT. */
+#define	R_X86_64_32	10	/* Add 32 bit zero extended symbol value */
+#define	R_X86_64_32S	11	/* Add 32 bit sign extended symbol value */
+#define	R_X86_64_16	12	/* Add 16 bit zero extended symbol value */
+#define	R_X86_64_PC16	13	/* Add 16 bit signed extended pc relative symbol value */
+#define	R_X86_64_8	14	/* Add 8 bit zero extended symbol value */
+#define	R_X86_64_PC8	15	/* Add 8 bit signed extended pc relative symbol value */
+
+#define	R_X86_64_COUNT	16	/* Count of defined relocation types. */
 
 /* Define "machine" characteristics */
-#define	ELF_TARG_CLASS	ELFCLASS32
+#define	ELF_TARG_CLASS	ELFCLASS64
 #define	ELF_TARG_DATA	ELFDATA2LSB
-#define	ELF_TARG_MACH	EM_386
+#define	ELF_TARG_MACH	EM_X86_64
 #define	ELF_TARG_VER	1
 
 #ifdef _KERNEL