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Diffstat (limited to 'arch/i386/cpu/start.S')
-rw-r--r--arch/i386/cpu/start.S96
1 files changed, 0 insertions, 96 deletions
diff --git a/arch/i386/cpu/start.S b/arch/i386/cpu/start.S
index 7def8def8..3cea04b4c 100644
--- 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: