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[prefix] Add PCI bus:dev.fn to ROM product string
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This allows multiple gPXE ROMs in a system to be disambiguated at boot
time; the PCI ID will show up in the boot menu for a BBS-compliant BIOS.
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Michael Brown committed May 21, 2008
1 parent f3aef4d commit fd0aef9
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Showing 3 changed files with 131 additions and 95 deletions.
64 changes: 56 additions & 8 deletions src/arch/i386/prefix/libprefix.S
View file
Expand Up @@ -48,30 +48,37 @@
*
* Parameters:
* %al : character to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* Nothing
* Corrupts:
* %ax
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
.section ".prefix.lib"
.code16
.globl print_character
print_character:
/* Preserve registers */
pushw %ax
pushw %bx
pushw %bp
/* Print character */
/* If %di is non-zero, write character to buffer and exit */
testw %di, %di
jz 1f
movb %al, %ds:(%di)
incw %di
jmp 3f
1: /* Print character */
movw $0x0007, %bx /* page 0, attribute 7 (normal) */
movb $0x0e, %ah /* write char, tty mode */
cmpb $0x0a, %al /* '\n'? */
jne 1f
jne 2f
int $0x10
movb $0x0d, %al
1: int $0x10
2: int $0x10
/* Restore registers and return */
popw %bp
3: popw %bp
popw %bx
popw %ax
ret
.size print_character, . - print_character

Expand All @@ -80,8 +87,10 @@ print_character:
*
* Parameters:
* %ds:si : string to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* %ds:si : character after terminating NUL
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
.section ".prefix.lib"
Expand Down Expand Up @@ -109,8 +118,9 @@ print_message:
* %al : byte to print
* %ax : word to print
* %eax : dword to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* Nothing
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
.section ".prefix.lib"
Expand Down Expand Up @@ -151,6 +161,44 @@ print_hex_nibble:
ret
.size print_hex_nibble, . - print_hex_nibble

/*****************************************************************************
* Utility function: print PCI bus:dev.fn
*
* Parameters:
* %ax : PCI bus:dev.fn to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
.section ".prefix.lib"
.code16
.globl print_pci_busdevfn
print_pci_busdevfn:
/* Preserve registers */
pushw %ax
/* Print bus */
xchgb %al, %ah
call print_hex_byte
/* Print ":" */
movb $':', %al
call print_character
/* Print device */
movb %ah, %al
shrb $3, %al
call print_hex_byte
/* Print "." */
movb $'.', %al
call print_character
/* Print function */
movb %ah, %al
andb $0x07, %al
call print_hex_nibble
/* Restore registers and return */
popw %ax
ret
.size print_pci_busdevfn, . - print_pci_busdevfn

/****************************************************************************
* pm_call (real-mode near call)
*
Expand Down
117 changes: 42 additions & 75 deletions src/arch/i386/prefix/pxeprefix.S
View file
Expand Up @@ -37,6 +37,7 @@
cld
/* Print welcome message */
movw $10f, %si
xorw %di, %di
call print_message
.section ".prefix.data"
10: .asciz "PXE->EB:"
Expand All @@ -48,24 +49,23 @@
*/
detect_pxenv:
/* Signature check */
les pxenv_segoff, %di
cmpl $0x4e455850, %es:(%di) /* 'PXEN' signature */
les pxenv_segoff, %bx
cmpl $0x4e455850, %es:(%bx) /* 'PXEN' signature */
jne no_pxenv
cmpw $0x2b56, %es:4(%di) /* 'V+' signature */
cmpw $0x2b56, %es:4(%bx) /* 'V+' signature */
jne no_pxenv
/* Record entry point and UNDI segments */
pushl %es:0x0a(%di) /* Entry point */
pushl %es:0x0a(%bx) /* Entry point */
popl entry_segoff
pushw %es:0x24(%di) /* UNDI code segment */
pushw %es:0x26(%di) /* UNDI code size */
pushw %es:0x24(%bx) /* UNDI code segment */
pushw %es:0x26(%bx) /* UNDI code size */
popl undi_code_segoff
pushw %es:0x20(%di) /* UNDI data segment */
pushw %es:0x22(%di) /* UNDI data size */
pushw %es:0x20(%bx) /* UNDI data segment */
pushw %es:0x22(%bx) /* UNDI data size */
popl undi_data_segoff
/* Print "PXENV+ at <address>" */
movw $10f, %si
call print_message
movw %bx, %di
call print_segoff
movb $',', %al
call print_character
Expand All @@ -86,20 +86,20 @@ no_pxenv:
*/
detect_ppxe:
/* Signature check */
les ppxe_segoff, %di
cmpl $0x45585021, %es:(%di) /* '!PXE' signature */
les ppxe_segoff, %bx
cmpl $0x45585021, %es:(%bx) /* '!PXE' signature */
jne no_ppxe
/* Record structure address, entry point, and UNDI segments */
pushw %es
popw ppxe_segment
movw %di, ppxe_offset
pushl %es:0x10(%di) /* Entry point */
movw %bx, ppxe_offset
pushl %es:0x10(%bx) /* Entry point */
popl entry_segoff
pushw %es:0x30(%di) /* UNDI code segment */
pushw %es:0x36(%di) /* UNDI code size */
pushw %es:0x30(%bx) /* UNDI code segment */
pushw %es:0x36(%bx) /* UNDI code size */
popl undi_code_segoff
pushw %es:0x28(%di) /* UNDI data segment */
pushw %es:0x2e(%di) /* UNDI data size */
pushw %es:0x28(%bx) /* UNDI data segment */
pushw %es:0x2e(%bx) /* UNDI data size */
popl undi_data_segoff
/* Print "!PXE at <address>" */
movw $10f, %si
Expand Down Expand Up @@ -167,23 +167,23 @@ print_structure_information:
/* Print entry point */
movw $10f, %si
call print_message
les entry_segoff, %di
les entry_segoff, %bx
call print_segoff
.section ".prefix.data"
10: .asciz " entry point at "
.previous
/* Print UNDI code segment */
movw $10f, %si
call print_message
les undi_code_segoff, %di
les undi_code_segoff, %bx
call print_segoff
.section ".prefix.data"
10: .asciz "\n UNDI code segment "
.previous
/* Print UNDI data segment */
movw $10f, %si
call print_message
les undi_data_segoff, %di
les undi_data_segoff, %bx
call print_segoff
.section ".prefix.data"
10: .asciz ", data segment "
Expand Down Expand Up @@ -271,8 +271,8 @@ unload_base_code:
call print_pxe_error
jmp 99f
1: /* Free base memory used by PXE base code */
movw %fs:(0x13), %si
movw undi_fbms_start, %di
movw undi_fbms_start, %ax
movw %fs:(0x13), %bx
call free_basemem
99:

Expand All @@ -289,8 +289,8 @@ unload_undi:
call print_pxe_error
jmp 99f
1: /* Free base memory used by UNDI */
movw undi_fbms_start, %si
movw undi_fbms_end, %di
movw undi_fbms_end, %ax
movw undi_fbms_start, %bx
call free_basemem
/* Clear UNDI_FL_STARTED */
andw $~UNDI_FL_STARTED, flags
Expand Down Expand Up @@ -324,9 +324,10 @@ finished:
* Subroutine: print segment:offset address
*
* Parameters:
* %es:%di : segment:offset address to print
* %es:%bx : segment:offset address to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* Nothing
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
print_segoff:
Expand All @@ -337,7 +338,7 @@ print_segoff:
call print_hex_word
movb $':', %al
call print_character
movw %di, %ax
movw %bx, %ax
call print_hex_word
/* Restore registers and return */
popw %ax
Expand All @@ -348,8 +349,9 @@ print_segoff:
*
* Parameters:
* %ax : word to print
* %ds:di : output buffer (or %di=0 to print to console)
* Returns:
* Nothing
* %ds:di : next character in output buffer (if applicable)
*****************************************************************************
*/
print_word:
Expand Down Expand Up @@ -378,44 +380,11 @@ print_word:
popw %ax
ret

/*****************************************************************************
* Subroutine: print PCI bus:dev.fn
*
* Parameters:
* %ax : PCI bus:dev.fn to print
* Returns:
* Nothing
*****************************************************************************
*/
print_pci_busdevfn:
/* Preserve registers */
pushw %ax
/* Print bus */
xchgb %al, %ah
call print_hex_byte
/* Print ":" */
movb $':', %al
call print_character
/* Print device */
movb %ah, %al
shrb $3, %al
call print_hex_byte
/* Print "." */
movb $'.', %al
call print_character
/* Print function */
movb %ah, %al
andb $0x07, %al
call print_hex_nibble
/* Restore registers and return */
popw %ax
ret

/*****************************************************************************
* Subroutine: zero 1kB block of base memory
*
* Parameters:
* %si : block to zero (in kB)
* %bx : block to zero (in kB)
* Returns:
* Nothing
*****************************************************************************
Expand All @@ -427,7 +396,7 @@ zero_kb:
pushw %di
pushw %es
/* Zero block */
movw %si, %ax
movw %bx, %ax
shlw $6, %ax
movw %ax, %es
movw $0x400, %cx
Expand All @@ -445,33 +414,31 @@ zero_kb:
* Subroutine: free and zero base memory
*
* Parameters:
* %si : Expected current free base memory counter (in kB)
* %di : Desired new free base memory counter (in kB)
* %ax : Desired new free base memory counter (in kB)
* %bx : Expected current free base memory counter (in kB)
* %fs : BIOS data segment (0x40)
* Returns:
* %ax : Actual new free base memory counter (in kB)
* None
*
* The base memory from %si kB to %di kB is unconditionally zeroed.
* The base memory from %bx kB to %ax kB is unconditionally zeroed.
* It will be freed if and only if the expected current free base
* memory counter (%si) matches the actual current free base memory
* memory counter (%bx) matches the actual current free base memory
* counter in 0x40:0x13; if this does not match then the memory will
* be leaked.
*****************************************************************************
*/
free_basemem:
/* Zero base memory */
pushw %si
1: cmpw %si, %di
pushw %bx
1: cmpw %bx, %ax
je 2f
call zero_kb
incw %si
incw %bx
jmp 1b
2: popw %si
2: popw %bx
/* Free base memory */
movw %fs:(0x13), %ax /* Current FBMS to %ax */
cmpw %ax, %si /* Update FBMS only if "old" value */
cmpw %fs:(0x13), %bx /* Update FBMS only if "old" value */
jne 1f /* is correct */
movw %di, %ax
1: movw %ax, %fs:(0x13)
ret

Expand Down

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