diff options
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S')
| -rw-r--r-- | qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S | 75 |
1 files changed, 61 insertions, 14 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S b/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S index 7c1ece791..7d5c1ed53 100644 --- a/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S +++ b/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S @@ -16,9 +16,13 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. * + * You can also choose to distribute this program under the terms of + * the Unmodified Binary Distribution Licence (as given in the file + * COPYING.UBDL), provided that you have satisfied its requirements. + * */ -FILE_LICENCE ( GPL2_OR_LATER ) +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ) .arch i386 @@ -296,11 +300,9 @@ copy_bytes: * Zero bytes * * Parameters: - * %ds:esi : source address * %es:edi : destination address * %ecx : length * Returns: - * %ds:esi : next source address * %es:edi : next destination address * Corrupts: * None @@ -396,8 +398,10 @@ process_bytes: movw %ax, %fs movw %ax, %gs +#ifdef NDEBUG /* Call memcpy()-like function */ call *%bx +#endif /* Return to (flat) real mode */ movl %cr0, %eax @@ -411,6 +415,20 @@ process_bytes: popw %fs popw %gs +#ifndef NDEBUG + /* Call memcpy()-like function in flat real mode (to allow for + * debug output via INT 10). + */ + pushw %ds + pushw %es + xorw %ax, %ax + movw %ax, %ds + movw %ax, %es + call *%bx + popw %es + popw %ds +#endif + /* Restore GDT */ data32 lgdt -8(%bp) addw $( 8 /* saved GDT */ + ( PM_DS + 8 ) /* GDT on stack */ ), %sp @@ -442,11 +460,11 @@ process_bytes: /* Convert %ds:esi and %es:edi back to physical addresses */ xorl %eax, %eax - movw %ds, %cx + movw %ds, %ax shll $4, %eax addl %eax, %esi xorl %eax, %eax - movw %es, %cx + movw %es, %ax shll $4, %eax addl %eax, %edi @@ -678,12 +696,21 @@ install: .globl install_prealloc install_prealloc: progress "install_prealloc:\n" - /* Save registers */ + /* Save registers on external stack */ pushal pushw %ds pushw %es cld /* Sanity: clear the direction flag asap */ + /* Switch to temporary stack in .bss16 */ + pushw %ss + popw %ds + movl %esp, %ecx + movw %bx, %ss + movl $_data16_memsz, %esp + pushw %ds + pushl %ecx + /* Set up %ds for (read-only) access to .prefix */ pushw %cs popw %ds @@ -710,6 +737,7 @@ install_prealloc: popl %esi #ifndef KEEP_IT_REAL + /* Access high memory by enabling the A20 gate. (We will * already have 4GB segment limits as a result of calling * install_block.) @@ -778,7 +806,7 @@ payload_death_message: movzwl %bx, %edi shll $4, %edi movl $_data16_filesz, %ecx - movl $_data16_memsz, %edx + movl $_data16_filesz, %edx /* do not zero our temporary stack */ call install_block /* .data16 */ /* Set up %ds for access to .data16 */ @@ -787,11 +815,8 @@ payload_death_message: /* Restore decompression temporary area physical address */ popl %edi -#ifdef KEEP_IT_REAL - /* Initialise libkir */ - movw %ax, (init_libkir_vector+2) - lcall *init_libkir_vector -#else +#ifndef KEEP_IT_REAL + /* Find a suitable decompression temporary area, if none specified */ pushl %eax testl %edi, %edi @@ -823,6 +848,22 @@ payload_death_message: call install_block popl %edi +#endif /* KEEP_IT_REAL */ + + /* Switch back to original stack and zero .bss16 */ + addr32 lss %ss:(%esp), %esp + pushl %edi + pushw %es + movw %bx, %es + movl $_data16_filesz, %edi + movl $_data16_memsz, %ecx + subl %edi, %ecx + call zero_bytes + popw %es + popl %edi + +#ifndef KEEP_IT_REAL + /* Initialise librm at current location */ progress " init_librm\n" movw %ax, (init_librm_vector+2) @@ -834,7 +875,6 @@ payload_death_message: incb memmap_post decl %ebp 1: - /* Call relocate() to determine target address for relocation. * relocate() will return with %esi, %edi and %ecx set up * ready for the copy to the new location. @@ -857,7 +897,14 @@ payload_death_message: /* Initialise librm at new location */ progress " init_librm\n" lcall *init_librm_vector -#endif + +#else /* KEEP_IT_REAL */ + + /* Initialise libkir */ + movw %ax, (init_libkir_vector+2) + lcall *init_libkir_vector + +#endif /* KEEP_IT_REAL */ /* Close access to payload */ progress " close_payload\n" |