x86: Set cold/warm boot flag

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

diff --git a/arch/i386/cpu/start.S b/arch/i386/cpu/start.S
index 25d32e658e60206915ff33573386eb4bdb0548e2..8fdcd81c1ea6306ad21286264c6f80f86795c8f6 100644 (file)
--- a/arch/i386/cpu/start.S
+++ b/arch/i386/cpu/start.S
@@ -1,7 +1,7 @@
 /*
  *  U-boot - i386 Startup Code
  *
- *  Copyright (c) 2002 Omicron Ceti AB, Daniel Engström <denaiel@omicron.se>
+ *  Copyright (c) 2002 Omicron Ceti AB, Daniel Engstr�m <denaiel@omicron.se>
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -25,6 +25,7 @@
 
 #include <config.h>
 #include <version.h>
+#include <asm/global_data.h>
 
 
 .section .text
@@ -33,103 +34,108 @@
 .type _start, @function
 .globl _i386boot_start
 _i386boot_start:
+       /*
+        * This is the fail safe 32-bit bootstrap entry point. The
+        * following code is not executed from a cold-reset (actually, a
+        * lot of it is, but from real-mode after cold reset. It is
+        * repeated here to put the board into a state as close to cold
+        * reset as necessary)
+        */
+       cli
+       cld
+
+       /* Turn of cache (this might require a 486-class CPU) */
+       movl    %cr0, %eax
+       orl     $0x60000000, %eax
+       movl    %eax, %cr0
+       wbinvd
+
+       /* Tell 32-bit code it is being entered from an in-RAM copy */
+       movw    $GD_FLG_WARM_BOOT, %bx
 _start:
-       movl    $0x18,%eax      /* Load our segement registes, the
+       /* This is the 32-bit cold-reset entry point */
+
+       movl    $0x18, %eax     /* Load our segement registes, the
                                 * gdt have already been loaded by start16.S */
-       movw    %ax,%fs
-       movw    %ax,%ds
-       movw    %ax,%gs
-       movw    %ax,%es
-       movw    %ax,%ss
+       movw    %ax, %fs
+       movw    %ax, %ds
+       movw    %ax, %gs
+       movw    %ax, %es
+       movw    %ax, %ss
 
-       /* We call a few functions in the board support package
-        * since we have no stack yet we'll have to use %ebp
-        * to store the return address */
+       /* Clear the interupt vectors */
+       lidt    blank_idt_ptr
+
+       /* Skip low-level initialization if not starting from cold-reset */
+       movl    %ebx, %ecx
+       andl    $GD_FLG_COLD_BOOT, %ecx
+       jz      skip_mem_init
 
        /* Early platform init (setup gpio, etc ) */
-       mov     $early_board_init_ret, %ebp
        jmp     early_board_init
+.globl early_board_init_ret
 early_board_init_ret:
 
-       /* The __port80 entry-point should be usabe by now */
-       /* so we try to indicate progress */
-       movw    $0x01, %ax
-       movl    $.progress0, %ebp
-       jmp     show_boot_progress_asm
-.progress0:
-
        /* size memory */
-       mov     $mem_init_ret, %ebp
-       jmp     mem_init
+       jmp     mem_init
+.globl mem_init_ret
 mem_init_ret:
 
+skip_mem_init:
+       /* fetch memory size (into %eax) */
+       jmp     get_mem_size
+.globl get_mem_size_ret
+get_mem_size_ret:
+
+#if CONFIG_SYS_SDRAM_ECC_ENABLE
+       /* Skip ECC initialization if not starting from cold-reset */
+       movl    %ebx, %ecx
+       andl    $GD_FLG_COLD_BOOT, %ecx
+       jz      init_ecc_ret
+       jmp     init_ecc
+
+.globl init_ecc_ret
+init_ecc_ret:
+#endif
+
        /* Check we have enough memory for stack */
        movl    $CONFIG_SYS_STACK_SIZE, %ecx
        cmpl    %ecx, %eax
-       jae     mem_ok
-
-       /* indicate (lack of) progress */
-       movw    $0x81, %ax
-       movl    $.progress0a, %ebp
-       jmp     show_boot_progress_asm
-.progress0a:
-       jmp     die
+       jb      die
 mem_ok:
        /* Set stack pointer to upper memory limit*/
-       movl    %eax, %esp
-
-       /* indicate progress */
-       movw    $0x02, %ax
-       movl    $.progress1, %ebp
-       jmp     show_boot_progress_asm
-.progress1:
+       movl    %eax, %esp
 
        /* Test the stack */
        pushl   $0
-       popl    %eax
-       cmpl    $0, %eax
-       jne     no_stack
+       popl    %ecx
+       cmpl    $0, %ecx
+       jne     die
        push    $0x55aa55aa
-       popl    %ebx
-       cmpl    $0x55aa55aa, %ebx
-       je      stack_ok
-
-no_stack:
-       /* indicate (lack of) progress */
-       movw    $0x82, %ax
-       movl    $.progress1a, %ebp
-       jmp     show_boot_progress_asm
-.progress1a:
-       jmp die
-
-
-stack_ok:
-       /* indicate progress */
-       movw    $0x03, %ax
-       movl    $.progress2, %ebp
-       jmp     show_boot_progress_asm
-.progress2:
+       popl    %ecx
+       cmpl    $0x55aa55aa, %ecx
+       jne     die
 
        wbinvd
 
-       /* Get upper memory limit */
-       movl %esp, %ecx
-       subl $CONFIG_SYS_STACK_SIZE, %ecx
+       /* Set the upper memory limit parameter */
+       subl    $CONFIG_SYS_STACK_SIZE, %eax
+
+       /* Reserve space for global data */
+       subl    $(GD_SIZE * 4), %eax
 
-       /* Create a Stack Frame */
-       pushl %ebp
-       movl %esp, %ebp
+       /* %eax points to the global data structure */
+       movl    %esp, (GD_RAM_SIZE * 4)(%eax)
+       movl    %ebx, (GD_FLAGS * 4)(%eax)
 
-       /* stack_limit parameter */
-       pushl   %ecx
        call    board_init_f    /* Enter, U-boot! */
 
        /* indicate (lack of) progress */
        movw    $0x85, %ax
-       movl    $.progress4a, %ebp
-       jmp     show_boot_progress_asm
-.progress4a:
-
 die:   hlt
        jmp     die
        hlt
+
+blank_idt_ptr:
+       .word   0               /* limit */
+       .long   0               /* base */