Merge branch 'master' of git://git.denx.de/u-boot-arm into HEAD

[u-boot] / arch / x86 / cpu / start.S

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 6c84c43f06aa917c466f50c58b40020c8fcc3284..f389584567cf2823e64e3ed515823585d7875802 100644 (file)
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -5,7 +5,7 @@
  * Graeme Russ, <graeme.russ@gmail.com>
  *
  * (C) Copyright 2002
- * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -29,7 +29,9 @@
 #include <config.h>
 #include <version.h>
 #include <asm/global_data.h>
+#include <asm/processor.h>
 #include <asm/processor-flags.h>
+#include <generated/generic-asm-offsets.h>
 
 .section .text
 .code32
@@ -47,7 +49,7 @@ _x86boot_start:
        cli
        cld
 
-       /* Turn of cache (this might require a 486-class CPU) */
+       /* Turn off cache (this might require a 486-class CPU) */
        movl    %cr0, %eax
        orl     $(X86_CR0_NW | X86_CR0_CD), %eax
        movl    %eax, %cr0
@@ -55,11 +57,17 @@ _x86boot_start:
 
        /* Tell 32-bit code it is being entered from an in-RAM copy */
        movw    $GD_FLG_WARM_BOOT, %bx
+       jmp     1f
 _start:
-       /* This is the 32-bit cold-reset entry point */
+       /*
+        * This is the 32-bit cold-reset entry point. Initialize %bx to 0
+        * in case we're preceeded by some sort of boot stub.
+        */
+       movw    $GD_FLG_COLD_BOOT, %bx
+1:
 
        /* 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
@@ -83,7 +91,30 @@ 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
+
+       /* Setup global descriptor table so gd->xyz works */
+       call    setup_gdt
 
        /* Set parameter to board_init_f() to boot flags */
        xorl    %eax, %eax
@@ -96,37 +127,78 @@ 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    (GD_RELOC_OFF * 4)(%edx), %ebp
+       /* Reserve space on stack for global data */
+       subl    $GENERATED_GBL_DATA_SIZE, %esp
 
-       /* Setup parameters to board_init_r() */
-       movl    %edx, %eax
-       movl    %ecx, %edx
+       /* Align global data to 16-byte boundary */
+       andl    $0xfffffff0, %esp
 
-       /* Jump to in-RAM copy of board_init_r() */
-       call    *%ebp
+       /* Setup first parameter to memcpy (and setup_gdt) */
+       movl    %esp, %eax
 
-die:   hlt
+       /* 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
+
+       /* Setup global descriptor table so gd->xyz works */
+       call    setup_gdt
+
+       /* Re-enter U-Boot by calling board_init_f_r */
+       call    board_init_f_r
+
+die:
+       hlt
        jmp     die
        hlt
 
 blank_idt_ptr:
        .word   0               /* limit */
        .long   0               /* base */
+
+       .p2align        2       /* force 4-byte alignment */
+
+multiboot_header:
+       /* magic */
+       .long   0x1BADB002
+       /* flags */
+       .long   (1 << 16)
+       /* checksum */
+       .long   -0x1BADB002 - (1 << 16)
+       /* header addr */
+       .long   multiboot_header - _x86boot_start + CONFIG_SYS_TEXT_BASE
+       /* load addr */
+       .long   CONFIG_SYS_TEXT_BASE
+       /* load end addr */
+       .long   0
+       /* bss end addr */
+       .long   0
+       /* entry addr */
+       .long   CONFIG_SYS_TEXT_BASE