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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/arch/x86/cpu/start.S
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/arch/x86/cpu/start.S')
-rw-r--r--qemu/roms/u-boot/arch/x86/cpu/start.S188
1 files changed, 188 insertions, 0 deletions
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
index 000000000..329bb3ab3
--- /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