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[prefix] Add .text16.early section
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Add a section .text16.early which is always kept inline with the
prefix.  This will allow for some code sharing between the .prefix and
.text16 sections.

Note that the simple solution of just prepending the .prefix section
to the .text16 section will not work, because a bug in Wyse Streaming
Manager server (WLDRM13.BIN) requires us to place a dummy PXENV+ entry
point at the start of .text16.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
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@mcb30
mcb30 committed Apr 20, 2010
1 parent 6c35a52 commit 9068249
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Showing 4 changed files with 150 additions and 39 deletions.
90 changes: 63 additions & 27 deletions src/arch/i386/prefix/libprefix.S
View file
Expand Up @@ -406,6 +406,7 @@ copy_bytes:
* %edx : total length of block (including any uninitialised data portion)
* Returns:
* %esi : next source physical address (will be a multiple of 16)
* %edi : next destination physical address (will be a multiple of 16)
* Corrupts:
* none
****************************************************************************
Expand All @@ -417,7 +418,6 @@ install_block:
pushw %ds
pushw %es
pushl %ecx
pushl %edi

/* Convert %esi and %edi to %ds:esi and %es:edi */
shrl $4, %esi
Expand Down Expand Up @@ -445,18 +445,23 @@ install_block:
rep addr32 stosb
popw %ax

/* Round up %esi to start of next source block */
/* Round up %esi and %edi to start of next blocks */
addl $0xf, %esi
andl $~0xf, %esi
addl $0xf, %edi
andl $~0xf, %edi

/* Convert %ds:esi back to a physical address */
/* Convert %ds:esi and %es:edi back to physical addresses */
xorl %ecx, %ecx
movw %ds, %cx
shll $4, %ecx
addl %ecx, %esi
xorl %ecx, %ecx
movw %es, %cx
shll $4, %ecx
addl %ecx, %edi

/* Restore registers and return */
popl %edi
popl %ecx
popw %es
popw %ds
Expand Down Expand Up @@ -626,6 +631,23 @@ install_prealloc:
/* Sanity: clear the direction flag asap */
cld

/* Copy decompression temporary area physical address to %ebp */
movl %edi, %ebp

/* Install .text16.early */
pushl %esi
xorl %esi, %esi
movw %cs, %si
shll $4, %esi
addl $_text16_early_lma, %esi
movzwl %ax, %edi
shll $4, %edi
movl $_text16_early_filesz, %ecx
movl $_text16_early_memsz, %edx
call install_block /* .text16.early */
popl %esi

/* Open up access to payload */
#ifndef KEEP_IT_REAL
/* Flatten real mode */
call flatten_real_mode
Expand All @@ -636,21 +658,17 @@ install_prealloc:
jnz 1f
movw %cs, %si
shll $4, %esi
1: addl $_payload_lma, %esi
1: addl %cs:payload_lma, %esi

/* Install .text16 and .data16 */
pushl %edi
movzwl %ax, %edi
shll $4, %edi
movl $_text16_memsz, %ecx
movl %ecx, %edx
call install_block /* .text16 */
/* Install .text16.late and .data16 */
movl $_text16_late_filesz, %ecx
movl $_text16_late_memsz, %edx
call install_block /* .text16.late */
movzwl %bx, %edi
shll $4, %edi
movl $_data16_filesz, %ecx
movl $_data16_memsz, %edx
call install_block /* .data16 */
popl %edi

/* Set up %ds for access to .data16 */
movw %bx, %ds
Expand All @@ -664,12 +682,14 @@ install_prealloc:
* prior to reading the E820 memory map and relocating
* properly.
*/
movl %ebp, %edi
movl $_textdata_filesz, %ecx
movl $_textdata_memsz, %edx
call install_block

/* Initialise librm at current location */
movw %ax, (init_librm_vector+2)
movl %ebp, %edi
lcall *init_librm_vector

/* Call relocate() to determine target address for relocation.
Expand All @@ -682,13 +702,13 @@ install_prealloc:
popl %edx /* discard */

/* Copy code to new location */
pushl %edi
xorw %ax, %ax
movw %ax, %es
movl %ebp, %edi
es rep addr32 movsb
popl %edi

/* Initialise librm at new location */
movl %ebp, %edi
lcall *init_librm_vector
#endif

Expand Down Expand Up @@ -719,6 +739,17 @@ prot_call_vector:
.size prot_call_vector, . - prot_call_vector
#endif

/* Payload address */
.section ".prefix.lib", "awx", @progbits
payload_lma:
.long 0
.section ".zinfo.fixup", "a", @progbits /* Compressor fixups */
.ascii "ADHL"
.long payload_lma
.long 1
.long 0
.previous

/****************************************************************************
* uninstall
*
Expand All @@ -745,27 +776,32 @@ uninstall:

/* File split information for the compressor */
#if COMPRESS
#define PACK_OR_COPY "PACK"
#else
#define PACK_OR_COPY "COPY"
#endif
.section ".zinfo", "a", @progbits
.ascii "COPY"
.long _prefix_lma
.long _prefix_filesz
.long _max_align
.ascii "PACK"
.long _text16_lma
.long _text16_filesz
.ascii PACK_OR_COPY
.long _text16_early_lma
.long _text16_early_filesz
.long _max_align
.ascii "PACK"
.ascii "PAYL"
.long 0
.long 0
.long _max_align
.ascii PACK_OR_COPY
.long _text16_late_lma
.long _text16_late_filesz
.long _max_align
.ascii PACK_OR_COPY
.long _data16_lma
.long _data16_filesz
.long _max_align
.ascii "PACK"
.ascii PACK_OR_COPY
.long _textdata_lma
.long _textdata_filesz
.long _max_align
#else /* COMPRESS */
.section ".zinfo", "a", @progbits
.ascii "COPY"
.long _prefix_lma
.long _filesz
.long _max_align
#endif /* COMPRESS */
16 changes: 15 additions & 1 deletion src/arch/i386/prefix/romprefix.S
View file
Expand Up @@ -362,7 +362,8 @@ got_pmm: /* PMM allocation succeeded */
addr32 rep movsb /* PMM presence implies flat real mode */
movl %edi, decompress_to
/* Shrink ROM */
movb $_prefix_memsz_sect, romheader_size
movb shrunk_rom_size, %al
movb %al, romheader_size
pmm_fail:
/* Restore upper register halves */
popal
Expand Down Expand Up @@ -488,6 +489,19 @@ image_source:
.long 0
.size image_source, . - image_source

/* Shrunk ROM size (in 512-byte sectors)
*
*/
shrunk_rom_size:
.byte 0
.size shrunk_rom_size, . - shrunk_rom_size
.section ".zinfo.fixup", "a", @progbits /* Compressor fixups */
.ascii "ADHB"
.long shrunk_rom_size
.long 512
.long 0
.previous

/* Temporary decompression area
*
* May be either at HIGHMEM_LOADPOINT, or within PMM-allocated block.
Expand Down
22 changes: 16 additions & 6 deletions src/arch/i386/scripts/i386.lds
View file
Expand Up @@ -45,17 +45,25 @@ SECTIONS {
*
*/

.text16 0x0 : AT ( _text16_lma ) {
.text16.early 0x0 : AT ( _text16_early_lma ) {
_text16 = .;
*(.text16.null)
. += 1; /* Prevent NULL being valid */
*(.text16.early)
*(.text16.early.*)
_etext16_early = .;
} .text16.late ALIGN ( _max_align ) : AT ( _text16_late_lma ) {
_text16_late = .;
*(.text16)
*(.text16.*)
_mtext16 = .;
} .bss.text16 (NOLOAD) : AT ( _end_lma ) {
_etext16 = .;
}
_text16_filesz = ABSOLUTE ( _mtext16 - _text16 );
_text16_early_filesz = ABSOLUTE ( _etext16_early - _text16 );
_text16_early_memsz = ABSOLUTE ( _etext16_early - _text16 );
_text16_late_filesz = ABSOLUTE ( _mtext16 - _text16_late );
_text16_late_memsz = ABSOLUTE ( _etext16 - _text16_late );
_text16_memsz = ABSOLUTE ( _etext16 - _text16 );

/*
Expand Down Expand Up @@ -168,10 +176,14 @@ SECTIONS {
_prefix_lma = .;
. += _prefix_filesz;

. = ALIGN ( _max_align );
_text16_early_lma = .;
. += _text16_early_filesz;

. = ALIGN ( _max_align );
_payload_lma = .;
_text16_lma = .;
. += _text16_filesz;
_text16_late_lma = .;
. += _text16_late_filesz;

. = ALIGN ( _max_align );
_data16_lma = .;
Expand All @@ -194,8 +206,6 @@ SECTIONS {
* Values calculated to save code from doing it
*
*/
_prefix_memsz_pgh = ( ( _prefix_memsz + 15 ) / 16 );
_prefix_memsz_sect = ( ( _prefix_memsz + 511 ) / 512 );
_text16_memsz_pgh = ( ( _text16_memsz + 15 ) / 16 );
_data16_memsz_pgh = ( ( _data16_memsz + 15 ) / 16 );
}

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