x86: Move loading of GTD to C code

[oweals/u-boot.git] / arch / i386 / cpu / start.S

diff --git a/arch/i386/cpu/start.S b/arch/i386/cpu/start.S
index 7def8def8b1d3b2398343fe0efbdc8cd935597b5..3cea04b4ce37bd480ada911f610d9a800e9255b4 100644 (file)
--- a/arch/i386/cpu/start.S
+++ b/arch/i386/cpu/start.S
@@ -100,53 +100,6 @@ mem_init_ret:
        jmp     get_mem_size
 get_mem_size_ret:
 
-       /*
-        * We are now in 'Flat Protected Mode' and we know how much memory
-        * the board has. The (temporary) Global Descriptor Table is not
-        * in a 'Safe' place (it is either in Flash which can be erased or
-        * reprogrammed or in a fail-safe boot-strap image which could be
-        * over-written).
-        *
-        * Move the final gdt to a safe place (top of RAM) and load it.
-        * This is not a trivial excercise - the lgdt instruction does not
-        * have a register operand (memory only) and we may well be
-        * running from Flash, so self modifying code will not work here.
-        * To overcome this, we copy a stub into upper memory along with
-        * the GDT.
-        */
-
-       /* Reduce upper memory limit by (Stub + GDT Pointer + GDT) */
-       subl    $(end_gdt_setup - start_gdt_setup), %eax
-
-       /* Copy the GDT and Stub */
-       movl    $start_gdt_setup, %esi
-       movl    %eax, %edi
-       movl    $(end_gdt_setup - start_gdt_setup), %ecx
-       shrl    $2, %ecx
-       cld
-       rep     movsl
-
-       /* write the lgdt 'parameter' */
-       subl    $(jmp_instr - start_gdt_setup - 4), %ebp
-       addl    %eax, %ebp
-       movl    $(gdt_ptr - start_gdt_setup), %ebx
-       addl    %eax, %ebx
-       movl    %ebx, (%ebp)
-
-       /* write the gdt address into the pointer */
-       movl    $(gdt_addr - start_gdt_setup), %ebp
-       addl    %eax, %ebp
-       movl    $(gdt - start_gdt_setup), %ebx
-       addl    %eax, %ebx
-       movl    %ebx, (%ebp)
-
-       /* Save the return address */
-       movl    $load_gdt_ret, %ebp
-
-       /* Load the new (safe) Global Descriptor Table */
-       jmp     *%eax
-
-load_gdt_ret:
        /* Check we have enough memory for stack */
        movl    $CONFIG_SYS_STACK_SIZE, %ecx
        cmpl    %ecx, %eax
@@ -221,52 +174,3 @@ die:       hlt
 blank_idt_ptr:
        .word   0               /* limit */
        .long   0               /* base */
-
-.align 4
-start_gdt_setup:
-       lgdt    gdt_ptr
-jmp_instr:
-       jmp     *%ebp
-
-.align 4
-gdt_ptr:
-       .word   0x30            /* limit (48 bytes = 6 GDT entries) */
-gdt_addr:
-       .long   gdt             /* base */
-
-       /* The GDT table ...
-        *
-        *       Selector       Type
-        *       0x00           NULL
-        *       0x08           Unused
-        *       0x10           32bit code
-        *       0x18           32bit data/stack
-        *       0x20           16bit code
-        *       0x28           16bit data/stack
-        */
-
-.align 4
-gdt:
-       .word   0, 0, 0, 0      /* NULL  */
-       .word   0, 0, 0, 0      /* unused */
-
-       .word   0xFFFF          /* 4Gb - (0x100000*0x1000 = 4Gb) */
-       .word   0               /* base address = 0 */
-       .word   0x9B00          /* code read/exec */
-       .word   0x00CF          /* granularity = 4096, 386 (+5th nibble of limit) */
-
-       .word   0xFFFF          /* 4Gb - (0x100000*0x1000 = 4Gb) */
-       .word   0x0             /* base address = 0 */
-       .word   0x9300          /* data read/write */
-       .word   0x00CF          /* granularity = 4096, 386 (+5th nibble of limit) */
-
-       .word   0xFFFF          /* 64kb */
-       .word   0               /* base address = 0 */
-       .word   0x9b00          /* data read/write */
-       .word   0x0010          /* granularity = 1  (+5th nibble of limit) */
-
-       .word   0xFFFF          /* 64kb */
-       .word   0               /* base address = 0 */
-       .word   0x9300          /* data read/write */
-       .word   0x0010          /* granularity = 1 (+5th nibble of limit) */
-end_gdt_setup: