diff options
author | jhb <jhb@FreeBSD.org> | 2000-07-06 00:22:50 +0000 |
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committer | jhb <jhb@FreeBSD.org> | 2000-07-06 00:22:50 +0000 |
commit | 06878d47d6d0d4dbe170795125fa60e8e102dbb0 (patch) | |
tree | ac3e959e396309b6d414eb0d971e05e2a215ee29 /sys/boot | |
parent | 1ebf348bd078d6c908fd9dae35b458b526cf8f7e (diff) | |
download | FreeBSD-src-06878d47d6d0d4dbe170795125fa60e8e102dbb0.zip FreeBSD-src-06878d47d6d0d4dbe170795125fa60e8e102dbb0.tar.gz |
Clarify the comments in here a bit. The first sector of boot2 is not just
zeros, it is actually the disklabel itself. boot2.ldr is simply a
placeholder in the boot2 binary.
Diffstat (limited to 'sys/boot')
-rw-r--r-- | sys/boot/i386/boot2/boot1.S | 4 | ||||
-rw-r--r-- | sys/boot/i386/boot2/boot1.s | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/sys/boot/i386/boot2/boot1.S b/sys/boot/i386/boot2/boot1.S index 0f15897..fee2fa0 100644 --- a/sys/boot/i386/boot2/boot1.S +++ b/sys/boot/i386/boot2/boot1.S @@ -139,13 +139,13 @@ main.4: xor %dx,%dx # Partition:drive # ahead and load up the first 16 sectors (boot1 + boot2) from that. When # we read it in, we conveniently use 0x8c00 as our transfer buffer. Thus, # boot1 ends up at 0x8c00, and boot2 starts at 0x8c00 + 0x200 = 0x8e00. -# The first part of boot2 is boot2.ldr, which is 0x200 bytes of zeros. +# The first part of boot2 is the disklabel, which is 0x200 bytes of zeros. # The second part is BTX, which is thus loaded into 0x9000, which is where # it also runs from. The boot2.bin binary starts right after the end of # BTX, so we have to figure out where the start of it is and then move the # binary to 0xb000. Normally, BTX clients start at MEM_USR, or 0xa000, but # when we use btxld create boot2, we use an entry point of 0x1000. That -# entry point is relative, to MEM_USR, thus boot2.bin starts at 0xb000. +# entry point is relative to MEM_USR; thus boot2.bin starts at 0xb000. # main.5: mov %dx,MEM_ARG # Save args movb $0x10,%dh # Sector count diff --git a/sys/boot/i386/boot2/boot1.s b/sys/boot/i386/boot2/boot1.s index 0f15897..fee2fa0 100644 --- a/sys/boot/i386/boot2/boot1.s +++ b/sys/boot/i386/boot2/boot1.s @@ -139,13 +139,13 @@ main.4: xor %dx,%dx # Partition:drive # ahead and load up the first 16 sectors (boot1 + boot2) from that. When # we read it in, we conveniently use 0x8c00 as our transfer buffer. Thus, # boot1 ends up at 0x8c00, and boot2 starts at 0x8c00 + 0x200 = 0x8e00. -# The first part of boot2 is boot2.ldr, which is 0x200 bytes of zeros. +# The first part of boot2 is the disklabel, which is 0x200 bytes of zeros. # The second part is BTX, which is thus loaded into 0x9000, which is where # it also runs from. The boot2.bin binary starts right after the end of # BTX, so we have to figure out where the start of it is and then move the # binary to 0xb000. Normally, BTX clients start at MEM_USR, or 0xa000, but # when we use btxld create boot2, we use an entry point of 0x1000. That -# entry point is relative, to MEM_USR, thus boot2.bin starts at 0xb000. +# entry point is relative to MEM_USR; thus boot2.bin starts at 0xb000. # main.5: mov %dx,MEM_ARG # Save args movb $0x10,%dh # Sector count |