diff options
Diffstat (limited to 'src/arch/i386/prefix')
| -rw-r--r-- | src/arch/i386/prefix/libprefix.S | 88 |
1 files changed, 39 insertions, 49 deletions
diff --git a/src/arch/i386/prefix/libprefix.S b/src/arch/i386/prefix/libprefix.S index d78113c0..12cf9184 100644 --- a/src/arch/i386/prefix/libprefix.S +++ b/src/arch/i386/prefix/libprefix.S @@ -162,7 +162,7 @@ pm_call: movl %eax, %cr0 /* Restore registers and flags */ - lret + lret /* will ljmp to 99f */ 99: popw %ss popw %ds popw %es @@ -298,16 +298,17 @@ alloc_basemem: /**************************************************************************** * install_basemem (real-mode near call) * - * Install .text16 and .data16 into base memory + * Install source block into base memory * - * Parameters: - * %ax : .text16 segment address - * %bx : .data16 segment address + * Parameters: * %esi : source physical address (must be a multiple of 16) + * %es : destination segment address + * %cx : length of (decompressed) data + * %dx : total length of block (including any uninitialised data portion) * Returns: * %esi : next source physical address (will be a multiple of 16) * Corrupts: - * none + * %edi, %ecx, %edx **************************************************************************** */ .section ".prefix.lib" @@ -315,42 +316,24 @@ alloc_basemem: install_basemem: /* Preserve registers */ pushw %ds - pushw %es - pushl %edi - pushl %ecx - pushl %edx - /* Install .text16 */ + /* Preserve original %esi */ pushl %esi - shrl $4, %esi - movw %si, %ds - xorw %si, %si - movw %ax, %es - xorl %edi, %edi - movl $_text16_size, %ecx - movl %ecx, %edx - call install_block - popl %ecx - addl %ecx, %esi - /* Install .data16 */ - pushl %esi + /* Install to specified address */ shrl $4, %esi movw %si, %ds xorw %si, %si - movw %bx, %es xorl %edi, %edi - movl $_data16_progbits_size, %ecx - movl $_data16_size, %edx + movzwl %cx, %ecx + movzwl %dx, %edx call install_block + + /* Fix up %esi for return */ popl %ecx addl %ecx, %esi /* Restore registers */ - popl %edx - popl %ecx - popl %edi - popw %es popw %ds ret .size install_basemem, . - install_basemem @@ -358,15 +341,17 @@ install_basemem: /**************************************************************************** * install_highmem (real-mode near call) * - * Install .text and .data into high memory + * Install source block into high memory * * Parameters: * %esi : source physical address (must be a multiple of 16) * %edi : destination physical address + * %ecx : length of (decompressed) data + * %edx : total length of block (including any uninitialised data portion) * Returns: * %esi : next source physical address (will be a multiple of 16) * Corrupts: - * none + * %edi, %ecx, %edx **************************************************************************** */ @@ -377,20 +362,12 @@ install_basemem: install_highmem: /* Preserve registers */ pushw %ax - pushl %edi - pushl %ecx - pushl %edx - /* Install .text and .data to specified address */ - movl $_textdata_progbits_size, %ecx - movl $_textdata_size, %edx + /* Install to specified address */ movw $install_block, %ax call pm_call /* Restore registers */ - popl %edx - popl %ecx - popl %edi popw %ax ret .size install_highmem, . - install_highmem @@ -425,7 +402,10 @@ install: install_prealloc: /* Save registers */ pushw %ds + pushw %es pushl %esi + pushl %ecx + pushl %edx /* Sanity: clear the direction flag asap */ cld @@ -436,7 +416,16 @@ install_prealloc: shll $4, %esi addl $_payload_offset, %esi - /* Install .text16 and .data16 */ + /* Install .text16 */ + movw %ax, %es + movw $_text16_size, %cx + movw %cx, %dx + call install_basemem + + /* Install .data16 */ + movw %bx, %es + movw $_data16_progbits_size, %cx + movw $_data16_size, %dx call install_basemem /* Set up %ds for access to .data16 */ @@ -447,16 +436,16 @@ install_prealloc: movw %ax, (init_libkir_vector+2) lcall *init_libkir_vector #else - /* Save registers */ - pushl %edi - pushl %ecx - /* Install .text and .data to temporary area in high memory, * prior to reading the E820 memory map and relocating * properly. */ movl $HIGHMEM_LOADPOINT, %edi + movl $_textdata_progbits_size, %ecx + movl $_textdata_size, %edx + pushl %edi call install_highmem + popl %edi /* Initialise librm at current location */ movw %ax, (init_librm_vector+2) @@ -469,7 +458,7 @@ install_prealloc: movw %ax, (prot_call_vector+2) pushl $relocate lcall *prot_call_vector - addw $4, %sp + popl %edx /* discard */ /* Copy code to new location */ pushl %edi @@ -482,11 +471,12 @@ install_prealloc: /* Initialise librm at new location */ lcall *init_librm_vector +#endif /* Restore registers */ + popl %edx popl %ecx - popl %edi -#endif popl %esi + popw %es popw %ds ret .size install_prealloc, . - install_prealloc |