X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=arch%2Fx86%2Fcpu%2Fstart.S;h=781d32447ba6c53a5fe50cc341b88c36f0be870d;hb=e1ffd81797d59652124bd9cda813a58644f5dea9;hp=ee0dabe4bcd049becb3c632ec408c98f32d13fb3;hpb=afd855d534de22aa625cb12aa9aa45e459f7de99;p=u-boot

diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index ee0dabe4bc..781d32447b 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -7,23 +7,7 @@
  * (C) Copyright 2002
  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
  *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <config.h>
@@ -55,8 +39,16 @@ _x86boot_start:
 	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 */
+	/*
+	 * 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
@@ -82,18 +74,61 @@ 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
+	 * and early malloc area.
+	 *
+	 * Stack grows down from top of CAR. We have:
+	 *
+	 * top-> CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE
+	 *	global_data
+	 *	x86 global descriptor table
+	 *	early malloc area
+	 *	stack
+	 * bottom-> CONFIG_SYS_CAR_ADDR
 	 */
-	movl	$CONFIG_SYS_INIT_SP_ADDR, %esp
 
-	/* Initialise the Global Data Pointer */
-	movl	$CONFIG_SYS_INIT_GD_ADDR, %eax
+	/* 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
+
+	/* Zero the global data since it won't happen later */
+	xorl	%eax, %eax
+	movl	$GENERATED_GBL_DATA_SIZE, %ecx
+	movl	%esp, %edi
+	rep	stosb
+
+	/* Setup first parameter to setup_gdt, pointer to global_data */
+	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
+	movl	%esp, %ecx
+
+#if defined(CONFIG_SYS_MALLOC_F_LEN)
+	subl	$CONFIG_SYS_MALLOC_F_LEN, %esp
 	movl	%eax, %edx
-	addl	$GENERATED_GBL_DATA_SIZE, %edx
-	call	init_gd;
+	addl	$GD_MALLOC_BASE, %edx
+	movl	%esp, (%edx)
+#endif
+
+	/* Align temporary global descriptor table to 16-byte boundary */
+	andl	$0xfffffff0, %esp
+
+	/* Set second parameter to setup_gdt */
+	movl	%ecx, %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
@@ -113,9 +148,39 @@ board_init_f_r_trampoline:
 	 * %eax = Address of top of new stack
 	 */
 
-	/* Setup stack in RAM */
+	/* 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