Merge branch 'master' of git://www.denx.de/git/u-boot-x86

[karo-tx-uboot.git] / arch / x86 / cpu / start.S

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index f87633b56121ca14aed1feb062c294643e428fd3..ec12e8044fd92a6f4c8fcf24057bb19f3645324f 100644 (file)
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -29,8 +29,9 @@
 #include <config.h>
 #include <version.h>
 #include <asm/global_data.h>
+#include <asm/processor.h>
 #include <asm/processor-flags.h>
-#include <generated/asm-offsets.h>
+#include <generated/generic-asm-offsets.h>
 
 .section .text
 .code32
@@ -58,7 +59,7 @@ _start:
        /* This is the 32-bit cold-reset entry point */
 
        /* Load the segement registes to match the gdt loaded in start16.S */
-       movl    $0x18, %eax
+       movl    $(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE), %eax
        movw    %ax, %fs
        movw    %ax, %ds
        movw    %ax, %gs
@@ -82,7 +83,33 @@ car_init_ret:
         * or fully initialised SDRAM - we really don't care which)
         * starting at CONFIG_SYS_CAR_ADDR to be used as a temporary stack
         */
-       movl    $CONFIG_SYS_INIT_SP_ADDR, %esp
+
+       /* Stack grows down from top of CAR */
+       movl    $(CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE), %esp
+
+       /* Reserve space on stack for global data */
+       subl    $GENERATED_GBL_DATA_SIZE, %esp
+
+       /* Align global data to 16-byte boundary */
+       andl    $0xfffffff0, %esp
+
+       /* Setup first parameter to setup_gdt */
+       movl    %esp, %eax
+
+       /* Reserve space for global descriptor table */
+       subl    $X86_GDT_SIZE, %esp
+
+       /* Align temporary global descriptor table to 16-byte boundary */
+       andl    $0xfffffff0, %esp
+
+       /* Set second parameter to setup_gdt */
+       movl    %esp, %edx
+
+       /* gd->gd_addr = gd (Required to allow gd->xyz to work) */
+       movl    %eax, (%eax)
+
+       /* Setup global descriptor table so gd->xyz works */
+       call    setup_gdt
 
        /* Set parameter to board_init_f() to boot flags */
        xorl    %eax, %eax
@@ -95,32 +122,55 @@ car_init_ret:
        movw    $0x85, %ax
        jmp     die
 
-.globl relocate_code
-.type relocate_code, @function
-relocate_code:
+.globl board_init_f_r_trampoline
+.type board_init_f_r_trampoline, @function
+board_init_f_r_trampoline:
        /*
         * SDRAM has been initialised, U-Boot code has been copied into
         * RAM, BSS has been cleared and relocation adjustments have been
         * made. It is now time to jump into the in-RAM copy of U-Boot
         *
-        * %eax = Address of top of stack
-        * %edx = Address of Global Data
-        * %ecx = Base address of in-RAM copy of U-Boot
+        * %eax = Address of top of new stack
         */
 
-       /* Setup stack in RAM */
+       /* Stack grows down from top of SDRAM */
        movl    %eax, %esp
 
-       /* Setup call address of in-RAM copy of board_init_r() */
-       movl    $board_init_r, %ebp
-       addl    (GENERATED_GD_RELOC_OFF)(%edx), %ebp
+       /* Reserve space on stack for global data */
+       subl    $GENERATED_GBL_DATA_SIZE, %esp
+
+       /* Align global data to 16-byte boundary */
+       andl    $0xfffffff0, %esp
+
+       /* Setup first parameter to memcpy (and setup_gdt) */
+       movl    %esp, %eax
+
+       /* Setup second parameter to memcpy */
+       fs movl 0, %edx
+
+       /* Set third parameter to memcpy */
+       movl    $GENERATED_GBL_DATA_SIZE, %ecx
+
+       /* Copy global data from CAR to SDRAM stack */
+       call    memcpy
+
+       /* Reserve space for global descriptor table */
+       subl    $X86_GDT_SIZE, %esp
+
+       /* Align global descriptor table to 16-byte boundary */
+       andl    $0xfffffff0, %esp
+
+       /* Set second parameter to setup_gdt */
+       movl    %esp, %edx
+
+       /* gd->gd_addr = gd (Required to allow gd->xyz to work) */
+       movl    %eax, (%eax)
 
-       /* Setup parameters to board_init_r() */
-       movl    %edx, %eax
-       movl    %ecx, %edx
+       /* Setup global descriptor table so gd->xyz works */
+       call    setup_gdt
 
-       /* Jump to in-RAM copy of board_init_r() */
-       call    *%ebp
+       /* Re-enter U-Boot by calling board_init_f_r */
+       call    board_init_f_r
 
 die:
        hlt