Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / u-boot / arch / x86 / cpu / start.S

diff --git a/qemu/roms/u-boot/arch/x86/cpu/start.S b/qemu/roms/u-boot/arch/x86/cpu/start.S
new file mode 100644 (file)
index 0000000..329bb3a
--- /dev/null
+++ b/qemu/roms/u-boot/arch/x86/cpu/start.S
@@ -0,0 +1,188 @@
+/*
+ *  U-boot - x86 Startup Code
+ *
+ * (C) Copyright 2008-2011
+ * Graeme Russ, <graeme.russ@gmail.com>
+ *
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#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
+.globl _start
+.type _start, @function
+.globl _x86boot_start
+_x86boot_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 off cache (this might require a 486-class CPU) */
+       movl    %cr0, %eax
+       orl     $(X86_CR0_NW | X86_CR0_CD), %eax
+       movl    %eax, %cr0
+       wbinvd
+
+       /* 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. 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    $(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE), %eax
+       movw    %ax, %fs
+       movw    %ax, %ds
+       movw    %ax, %gs
+       movw    %ax, %es
+       movw    %ax, %ss
+
+       /* Clear the interrupt vectors */
+       lidt    blank_idt_ptr
+
+       /* Early platform init (setup gpio, etc ) */
+       jmp     early_board_init
+.globl early_board_init_ret
+early_board_init_ret:
+
+       /* Initialise Cache-As-RAM */
+       jmp     car_init
+.globl car_init_ret
+car_init_ret:
+       /*
+        * We now have CONFIG_SYS_CAR_SIZE bytes of Cache-As-RAM (or SRAM,
+        * or fully initialised SDRAM - we really don't care which)
+        * starting at CONFIG_SYS_CAR_ADDR to be used as a temporary stack
+        */
+
+       /* 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
+       movw    %bx, %ax
+
+       /* Enter, U-boot! */
+       call    board_init_f
+
+       /* indicate (lack of) progress */
+       movw    $0x85, %ax
+       jmp     die
+
+.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 new stack
+        */
+
+       /* Stack grows down from top of SDRAM */
+       movl    %eax, %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 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
+
+       /* 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