1. Remove all references to cyloffset, it has been unused for some time.

2.  New detection code so we know what boot code called us.

3.  Remove old DISKLESS support code and halt if we are called by that boot
    code as it will NOT work with the new nfs_diskless structure.

This is really in preperation for new boot code and new diskless support.

Reviewed by:	davidg

5 files changed, 230 insertions, 60 deletions

diff --git a/sys/amd64/amd64/locore.S b/sys/amd64/amd64/locore.S
index bc7b854..4b6df54 100644
--- a/sys/amd64/amd64/locore.S
+++ b/sys/amd64/amd64/locore.S
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)locore.s	7.3 (Berkeley) 5/13/91
- *	$Id: locore.s,v 1.29 1994/09/26 16:56:22 pst Exp $
+ *	$Id: locore.s,v 1.30 1994/10/01 02:56:01 davidg Exp $
  */
 
 /*
@@ -125,9 +125,6 @@ _KERNend:	.long	0			/* phys addr end of kernel (just after bss) */
 _IdlePTD:	.long	0			/* phys addr of kernel PTD */
 _KPTphys:	.long	0			/* phys addr of kernel page tables */
 
-	.globl	_cyloffset
-_cyloffset:	.long	0			/* cylinder offset from boot blocks */
-
 	.globl	_proc0paddr
 _proc0paddr:	.long	0			/* address of proc 0 address space */
 
@@ -161,24 +158,93 @@ tmpstk:
 NON_GPROF_ENTRY(btext)
 	movw	$0x1234,0x472			/* warm boot */
 	jmp	1f
+	/*
+	 * XXX now that we load at 1MB is this still really used?
+	 */
 	.org	0x500				/* space for BIOS variables */
 
- 1:
+1:
 	/* Don't trust what the BIOS gives for eflags. */
 	pushl	$PSL_MBO
 	popfl
 
 	/*
-	 * pass parameters on stack (howto, bootdev, unit, cyloffset, esym)
-	 * note: (%esp) is return address of boot
-	 * ( if we want to hold onto /boot, it's physical %esp up to _end)
+	 * This code is called in different ways depending on what loaded
+	 * and started the kernel.  This is used to detect how we get the
+	 * arguments from the other code and what we do with them.
+	 *
+	 * Old disk boot blocks:
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 *	[return address == 0, and can NOT be returned to]
+	 *	[cyloffset was not supported by the FreeBSD boot code
+	 *	 and always passed in as 0]
+	 *	[esym is also known as total in the boot code, and
+	 *	 was never properly supported by the FreeBSD boot code]
+	 *
+	 * Old diskless netboot code:
+	 *	(*btext)(0,0,0,0,&nfsdiskless,0,0,0);
+	 *	[return address != 0, and can NOT be returned to]
+	 *	If we are being booted by this code it will NOT work,
+	 *	so we are just going to halt if we find this case.
+	 *
+	 * New uniform boot code:
+	 *	(*btext)(howto, bootdev, 0, 0, 0, &bootinfo)
+	 *	[return address != 0, and can be returned to]
+	 *
+	 * There may seem to be a lot of wasted arguments in here, but
+	 * that is so the newer boot code can still load very old kernels.
+	 */
+
+	/*
+	 * The old style disk boot blocks fake a frame on the stack and
+	 * did an lret to get here.  The frame on the stack has a return
+	 * address of 0.
+	 */
+	cmpl	$0,0x00(%esp)
+	je	2f				/* olddiskboot: */
+
+	/*
+	 * We have some form of return address, so this is either the
+	 * old diskless netboot code, or the new uniform code.  That can
+	 * be detected by looking at the 5th argument, it if is 0 we
+	 * we are being booted by the new unifrom boot code.
 	 */
+	cmpl	$0,0x14(%esp)
+	je	1f				/* newboot: */
+
+	/*
+	 * Seems we have been loaded by the old diskless boot code, we
+	 * don't stand a chance of running as the diskless structure
+	 * changed considerably between the two, so just halt.
+	 */
+	 hlt
+
+	/*
+	 * We have been loaded by the new uniform boot code, this kernel
+	 * is not yet ready to handle that, so for now fix up the stack
+	 * like a real subroutine and then return to the boot loader with
+	 * a status of 1 to indicate this error.
+	 */
+1:	/* newboot: */
+	 pushl	%ebp
+	 movl	%esp,%ebp
+	 movl	$1,%eax
+	 leave
+	 ret
+
+	/*
+	 * The old style disk boot.
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 * cyloffset is no longer copied
+	 * XXX Is esym still used for the end of the kernel some place???
+	 *     for now make sure we keep a correct value in it until I
+	 *     can deterimine that.
+	 */
+2:	/* olddiskboot: */
 	movl	4(%esp),%eax
 	movl	%eax,_boothowto-KERNBASE
 	movl	8(%esp),%eax
 	movl	%eax,_bootdev-KERNBASE
-	movl	12(%esp),%eax
-	movl	%eax,_cyloffset-KERNBASE
 	movl	16(%esp),%eax
 	addl	$KERNBASE,%eax
 	movl	%eax,_esym-KERNBASE
@@ -200,14 +266,6 @@ NON_GPROF_ENTRY(btext)
  	addl	$KERNBASE, %eax
  	movl	%eax, _video_mode_ptr-KERNBASE	
 
-#ifdef DISKLESS					/* Copy diskless structure */
-	movl	_nfs_diskless_size-KERNBASE,%ecx
-	movl	20(%esp),%esi
-	movl	$(_nfs_diskless-KERNBASE),%edi
-	cld
-	rep
-	movsb
-#endif
 #ifdef APM
 	/*
 	 * Setup APM BIOS:
diff --git a/sys/amd64/amd64/locore.s b/sys/amd64/amd64/locore.s
index bc7b854..4b6df54 100644
--- a/sys/amd64/amd64/locore.s
+++ b/sys/amd64/amd64/locore.s
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)locore.s	7.3 (Berkeley) 5/13/91
- *	$Id: locore.s,v 1.29 1994/09/26 16:56:22 pst Exp $
+ *	$Id: locore.s,v 1.30 1994/10/01 02:56:01 davidg Exp $
  */
 
 /*
@@ -125,9 +125,6 @@ _KERNend:	.long	0			/* phys addr end of kernel (just after bss) */
 _IdlePTD:	.long	0			/* phys addr of kernel PTD */
 _KPTphys:	.long	0			/* phys addr of kernel page tables */
 
-	.globl	_cyloffset
-_cyloffset:	.long	0			/* cylinder offset from boot blocks */
-
 	.globl	_proc0paddr
 _proc0paddr:	.long	0			/* address of proc 0 address space */
 
@@ -161,24 +158,93 @@ tmpstk:
 NON_GPROF_ENTRY(btext)
 	movw	$0x1234,0x472			/* warm boot */
 	jmp	1f
+	/*
+	 * XXX now that we load at 1MB is this still really used?
+	 */
 	.org	0x500				/* space for BIOS variables */
 
- 1:
+1:
 	/* Don't trust what the BIOS gives for eflags. */
 	pushl	$PSL_MBO
 	popfl
 
 	/*
-	 * pass parameters on stack (howto, bootdev, unit, cyloffset, esym)
-	 * note: (%esp) is return address of boot
-	 * ( if we want to hold onto /boot, it's physical %esp up to _end)
+	 * This code is called in different ways depending on what loaded
+	 * and started the kernel.  This is used to detect how we get the
+	 * arguments from the other code and what we do with them.
+	 *
+	 * Old disk boot blocks:
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 *	[return address == 0, and can NOT be returned to]
+	 *	[cyloffset was not supported by the FreeBSD boot code
+	 *	 and always passed in as 0]
+	 *	[esym is also known as total in the boot code, and
+	 *	 was never properly supported by the FreeBSD boot code]
+	 *
+	 * Old diskless netboot code:
+	 *	(*btext)(0,0,0,0,&nfsdiskless,0,0,0);
+	 *	[return address != 0, and can NOT be returned to]
+	 *	If we are being booted by this code it will NOT work,
+	 *	so we are just going to halt if we find this case.
+	 *
+	 * New uniform boot code:
+	 *	(*btext)(howto, bootdev, 0, 0, 0, &bootinfo)
+	 *	[return address != 0, and can be returned to]
+	 *
+	 * There may seem to be a lot of wasted arguments in here, but
+	 * that is so the newer boot code can still load very old kernels.
+	 */
+
+	/*
+	 * The old style disk boot blocks fake a frame on the stack and
+	 * did an lret to get here.  The frame on the stack has a return
+	 * address of 0.
+	 */
+	cmpl	$0,0x00(%esp)
+	je	2f				/* olddiskboot: */
+
+	/*
+	 * We have some form of return address, so this is either the
+	 * old diskless netboot code, or the new uniform code.  That can
+	 * be detected by looking at the 5th argument, it if is 0 we
+	 * we are being booted by the new unifrom boot code.
 	 */
+	cmpl	$0,0x14(%esp)
+	je	1f				/* newboot: */
+
+	/*
+	 * Seems we have been loaded by the old diskless boot code, we
+	 * don't stand a chance of running as the diskless structure
+	 * changed considerably between the two, so just halt.
+	 */
+	 hlt
+
+	/*
+	 * We have been loaded by the new uniform boot code, this kernel
+	 * is not yet ready to handle that, so for now fix up the stack
+	 * like a real subroutine and then return to the boot loader with
+	 * a status of 1 to indicate this error.
+	 */
+1:	/* newboot: */
+	 pushl	%ebp
+	 movl	%esp,%ebp
+	 movl	$1,%eax
+	 leave
+	 ret
+
+	/*
+	 * The old style disk boot.
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 * cyloffset is no longer copied
+	 * XXX Is esym still used for the end of the kernel some place???
+	 *     for now make sure we keep a correct value in it until I
+	 *     can deterimine that.
+	 */
+2:	/* olddiskboot: */
 	movl	4(%esp),%eax
 	movl	%eax,_boothowto-KERNBASE
 	movl	8(%esp),%eax
 	movl	%eax,_bootdev-KERNBASE
-	movl	12(%esp),%eax
-	movl	%eax,_cyloffset-KERNBASE
 	movl	16(%esp),%eax
 	addl	$KERNBASE,%eax
 	movl	%eax,_esym-KERNBASE
@@ -200,14 +266,6 @@ NON_GPROF_ENTRY(btext)
  	addl	$KERNBASE, %eax
  	movl	%eax, _video_mode_ptr-KERNBASE	
 
-#ifdef DISKLESS					/* Copy diskless structure */
-	movl	_nfs_diskless_size-KERNBASE,%ecx
-	movl	20(%esp),%esi
-	movl	$(_nfs_diskless-KERNBASE),%edi
-	cld
-	rep
-	movsb
-#endif
 #ifdef APM
 	/*
 	 * Setup APM BIOS:
diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index 3242846..2f45046 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.66 1994/09/24 12:22:47 davidg Exp $
+ *	$Id: machdep.c,v 1.67 1994/10/01 02:56:02 davidg Exp $
  */
 
 #include "npx.h"
@@ -147,8 +147,6 @@ int biosmem;
 
 vm_offset_t	phys_avail[6];
 
-extern cyloffset;
-
 int cpu_class;
 
 void dumpsys __P((void));
diff --git a/sys/i386/i386/locore.s b/sys/i386/i386/locore.s
index bc7b854..4b6df54 100644
--- a/sys/i386/i386/locore.s
+++ b/sys/i386/i386/locore.s
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)locore.s	7.3 (Berkeley) 5/13/91
- *	$Id: locore.s,v 1.29 1994/09/26 16:56:22 pst Exp $
+ *	$Id: locore.s,v 1.30 1994/10/01 02:56:01 davidg Exp $
  */
 
 /*
@@ -125,9 +125,6 @@ _KERNend:	.long	0			/* phys addr end of kernel (just after bss) */
 _IdlePTD:	.long	0			/* phys addr of kernel PTD */
 _KPTphys:	.long	0			/* phys addr of kernel page tables */
 
-	.globl	_cyloffset
-_cyloffset:	.long	0			/* cylinder offset from boot blocks */
-
 	.globl	_proc0paddr
 _proc0paddr:	.long	0			/* address of proc 0 address space */
 
@@ -161,24 +158,93 @@ tmpstk:
 NON_GPROF_ENTRY(btext)
 	movw	$0x1234,0x472			/* warm boot */
 	jmp	1f
+	/*
+	 * XXX now that we load at 1MB is this still really used?
+	 */
 	.org	0x500				/* space for BIOS variables */
 
- 1:
+1:
 	/* Don't trust what the BIOS gives for eflags. */
 	pushl	$PSL_MBO
 	popfl
 
 	/*
-	 * pass parameters on stack (howto, bootdev, unit, cyloffset, esym)
-	 * note: (%esp) is return address of boot
-	 * ( if we want to hold onto /boot, it's physical %esp up to _end)
+	 * This code is called in different ways depending on what loaded
+	 * and started the kernel.  This is used to detect how we get the
+	 * arguments from the other code and what we do with them.
+	 *
+	 * Old disk boot blocks:
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 *	[return address == 0, and can NOT be returned to]
+	 *	[cyloffset was not supported by the FreeBSD boot code
+	 *	 and always passed in as 0]
+	 *	[esym is also known as total in the boot code, and
+	 *	 was never properly supported by the FreeBSD boot code]
+	 *
+	 * Old diskless netboot code:
+	 *	(*btext)(0,0,0,0,&nfsdiskless,0,0,0);
+	 *	[return address != 0, and can NOT be returned to]
+	 *	If we are being booted by this code it will NOT work,
+	 *	so we are just going to halt if we find this case.
+	 *
+	 * New uniform boot code:
+	 *	(*btext)(howto, bootdev, 0, 0, 0, &bootinfo)
+	 *	[return address != 0, and can be returned to]
+	 *
+	 * There may seem to be a lot of wasted arguments in here, but
+	 * that is so the newer boot code can still load very old kernels.
+	 */
+
+	/*
+	 * The old style disk boot blocks fake a frame on the stack and
+	 * did an lret to get here.  The frame on the stack has a return
+	 * address of 0.
+	 */
+	cmpl	$0,0x00(%esp)
+	je	2f				/* olddiskboot: */
+
+	/*
+	 * We have some form of return address, so this is either the
+	 * old diskless netboot code, or the new uniform code.  That can
+	 * be detected by looking at the 5th argument, it if is 0 we
+	 * we are being booted by the new unifrom boot code.
 	 */
+	cmpl	$0,0x14(%esp)
+	je	1f				/* newboot: */
+
+	/*
+	 * Seems we have been loaded by the old diskless boot code, we
+	 * don't stand a chance of running as the diskless structure
+	 * changed considerably between the two, so just halt.
+	 */
+	 hlt
+
+	/*
+	 * We have been loaded by the new uniform boot code, this kernel
+	 * is not yet ready to handle that, so for now fix up the stack
+	 * like a real subroutine and then return to the boot loader with
+	 * a status of 1 to indicate this error.
+	 */
+1:	/* newboot: */
+	 pushl	%ebp
+	 movl	%esp,%ebp
+	 movl	$1,%eax
+	 leave
+	 ret
+
+	/*
+	 * The old style disk boot.
+	 *	(*btext)(howto, bootdev, cyloffset, esym);
+	 * cyloffset is no longer copied
+	 * XXX Is esym still used for the end of the kernel some place???
+	 *     for now make sure we keep a correct value in it until I
+	 *     can deterimine that.
+	 */
+2:	/* olddiskboot: */
 	movl	4(%esp),%eax
 	movl	%eax,_boothowto-KERNBASE
 	movl	8(%esp),%eax
 	movl	%eax,_bootdev-KERNBASE
-	movl	12(%esp),%eax
-	movl	%eax,_cyloffset-KERNBASE
 	movl	16(%esp),%eax
 	addl	$KERNBASE,%eax
 	movl	%eax,_esym-KERNBASE
@@ -200,14 +266,6 @@ NON_GPROF_ENTRY(btext)
  	addl	$KERNBASE, %eax
  	movl	%eax, _video_mode_ptr-KERNBASE	
 
-#ifdef DISKLESS					/* Copy diskless structure */
-	movl	_nfs_diskless_size-KERNBASE,%ecx
-	movl	20(%esp),%esi
-	movl	$(_nfs_diskless-KERNBASE),%edi
-	cld
-	rep
-	movsb
-#endif
 #ifdef APM
 	/*
 	 * Setup APM BIOS:
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index 3242846..2f45046 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)machdep.c	7.4 (Berkeley) 6/3/91
- *	$Id: machdep.c,v 1.66 1994/09/24 12:22:47 davidg Exp $
+ *	$Id: machdep.c,v 1.67 1994/10/01 02:56:02 davidg Exp $
  */
 
 #include "npx.h"
@@ -147,8 +147,6 @@ int biosmem;
 
 vm_offset_t	phys_avail[6];
 
-extern cyloffset;
-
 int cpu_class;
 
 void dumpsys __P((void));