diff options
| -rw-r--r-- | c/src/lib/libbsp/i386/pc386/start/start16.s | 29 |
1 files changed, 3 insertions, 26 deletions
diff --git a/c/src/lib/libbsp/i386/pc386/start/start16.s b/c/src/lib/libbsp/i386/pc386/start/start16.s index c5febfda92..c10a658718 100644 --- a/c/src/lib/libbsp/i386/pc386/start/start16.s +++ b/c/src/lib/libbsp/i386/pc386/start/start16.s @@ -33,13 +33,6 @@ .set HDROFF, 0x24 # offset into bin2boot header of start32 addr .set STACKOFF, 0x200-0x10 # offset to load into %esp, from start of image -/*----------------------------------------------------------------------------+ -| A Descriptor table register has the following format: -+----------------------------------------------------------------------------*/ - -.set DTR_LIMIT, 0 # offset of two byte limit -.set DTR_BASE, 2 # offset of four byte base address -.set DTR_SIZE, 6 # size of DTR register /*----------------------------------------------------------------------------+ | CODE section @@ -61,13 +54,6 @@ _start16: movw %ax, %es # movw %ax, %ss # -.code32 - - movl $STACKOFF, %esp # set stack pointer - movl $STACKOFF, %ebp # - -.code16 - #if defined(RTEMS_VIDEO_80x50) /*---------------------------------------------------------------------+ @@ -94,7 +80,6 @@ _start16: +---------------------------------------------------------------------*/ lgdt gdtptr - start16 # load Global Descriptor Table - lidt idtptr - start16 # load Interrupt Descriptor Table movl %cr0, %eax orl $CR0_PE, %eax @@ -112,8 +97,8 @@ _start16: movl %ax, %ds movl %ax, %es movl %ax, %ss - addl $start16, %esp # fix up stack pointer - addl $start16, %ebp # fix up stack pointer + movl $start16 + STACKOFF, %esp # set up stack pointer + addl $start16 + STACKOFF, %ebp # set up stack pointer /*---------------------------------------------------------------------+ | we have to enable A20 in order to access memory above 1MByte @@ -174,7 +159,7 @@ no_output: * GLOBAL DESCRIPTOR TABLE * **************************/ - .align 4 + .p2align 4 gdtptr: /* we use the NULL descriptor to store the GDT pointer - a trick quite nifty due to: Robert Collins (rcollins@x86.org) */ @@ -192,11 +177,3 @@ gdtptr: .set gdtlen, . - gdtptr # length of GDT -/************************************* -* INTERRUPT DESCRIPTOR TABLE POINTER * -*************************************/ - - .align 4 -idtptr: - .word 0x07ff # limit at maximum (allows all 256 interrupts) - .word 0, 0 # base at 0 |