arch/arm/cpu/s3c44b0/start.S - platform/external/u-boot - Gitiles

 /*
  * Startup Code for S3C44B0 CPU-core
  *
  * (C) Copyright 2004
  * DAVE Srl
  *
  * http://www.dave-tech.it
  * http://www.wawnet.biz
  * mailto:info@wawnet.biz
  *
  * 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
  */

 #include <asm-offsets.h>
 #include <config.h>
 #include <version.h>

 /*
  * Jump vector table
  */


 .globl _start
 _start:	b       reset
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000
 	add	pc, pc, #0x0c000000

 	.balignl 16,0xdeadbeef


 /*
  *************************************************************************
  *
  * Startup Code (reset vector)
  *
  * do important init only if we don't start from memory!
  * relocate u-boot to ram
  * setup stack
  * jump to second stage
  *
  *************************************************************************
  */

 .globl _TEXT_BASE
 _TEXT_BASE:
 	.word	CONFIG_SYS_TEXT_BASE

 /*
  * These are defined in the board-specific linker script.
  * Subtracting _start from them lets the linker put their
  * relative position in the executable instead of leaving
  * them null.
  */
 .globl _bss_start_ofs
 _bss_start_ofs:
 	.word __bss_start - _start

 .globl _bss_end_ofs
 _bss_end_ofs:
 	.word _end - _start

 #ifdef CONFIG_USE_IRQ
 /* IRQ stack memory (calculated at run-time) */
 .globl IRQ_STACK_START
 IRQ_STACK_START:
 	.word	0x0badc0de

 /* IRQ stack memory (calculated at run-time) */
 .globl FIQ_STACK_START
 FIQ_STACK_START:
 	.word 0x0badc0de
 #endif

 /* IRQ stack memory (calculated at run-time) + 8 bytes */
 .globl IRQ_STACK_START_IN
 IRQ_STACK_START_IN:
 	.word	0x0badc0de

 /*
  * the actual reset code
  */

 reset:
 	/*
 	 * set the cpu to SVC32 mode
 	 */
 	mrs	r0,cpsr
 	bic	r0,r0,#0x1f
 	orr	r0,r0,#0xd3
 	msr	cpsr,r0

 	/*
 	 * we do sys-critical inits only at reboot,
 	 * not when booting from ram!
 	 */
 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
 	bl	cpu_init_crit
 	/*
 	 * before relocating, we have to setup RAM timing
 	 * because memory timing is board-dependend, you will
 	 * find a lowlevel_init.S in your board directory.
 	 */
 	bl	lowlevel_init
 #endif

 /* Set stackpointer in internal RAM to call board_init_f */
 call_board_init_f:
 	ldr	sp, =(CONFIG_SYS_INIT_SP_ADDR)
 	bic	sp, sp, #7 /* 8-byte alignment for ABI compliance */
 	ldr	r0,=0x00000000
 	bl	board_init_f

 /*------------------------------------------------------------------------------*/

 /*
  * void relocate_code (addr_sp, gd, addr_moni)
  *
  * This "function" does not return, instead it continues in RAM
  * after relocating the monitor code.
  *
  */
 	.globl	relocate_code
 relocate_code:
 	mov	r4, r0	/* save addr_sp */
 	mov	r5, r1	/* save addr of gd */
 	mov	r6, r2	/* save addr of destination */

 	/* Set up the stack						    */
 stack_setup:
 	mov	sp, r4

 	adr	r0, _start
 	cmp	r0, r6
 	beq	clear_bss		/* skip relocation */
 	mov	r1, r6			/* r1 <- scratch for copy_loop */
 	ldr	r2, _TEXT_BASE
 	ldr	r3, _bss_start_ofs
 	add	r2, r0, r3		/* r2 <- source end address	    */

 copy_loop:
 	ldmia	r0!, {r9-r10}		/* copy from source address [r0]    */
 	stmia	r1!, {r9-r10}		/* copy to   target address [r1]    */
 	cmp	r0, r2			/* until source end address [r2]    */
 	blo	copy_loop

 #ifndef CONFIG_PRELOADER
 	/*
 	 * fix .rel.dyn relocations
 	 */
 	ldr	r0, _TEXT_BASE		/* r0 <- Text base */
 	sub	r9, r6, r0		/* r9 <- relocation offset */
 	ldr	r10, _dynsym_start_ofs	/* r10 <- sym table ofs */
 	add	r10, r10, r0		/* r10 <- sym table in FLASH */
 	ldr	r2, _rel_dyn_start_ofs	/* r2 <- rel dyn start ofs */
 	add	r2, r2, r0		/* r2 <- rel dyn start in FLASH */
 	ldr	r3, _rel_dyn_end_ofs	/* r3 <- rel dyn end ofs */
 	add	r3, r3, r0		/* r3 <- rel dyn end in FLASH */
 fixloop:
 	ldr	r0, [r2]		/* r0 <- location to fix up, IN FLASH! */
 	add	r0, r0, r9		/* r0 <- location to fix up in RAM */
 	ldr	r1, [r2, #4]
 	and	r8, r1, #0xff
 	cmp	r8, #23			/* relative fixup? */
 	beq	fixrel
 	cmp	r8, #2			/* absolute fixup? */
 	beq	fixabs
 	/* ignore unknown type of fixup */
 	b	fixnext
 fixabs:
 	/* absolute fix: set location to (offset) symbol value */
 	mov	r1, r1, LSR #4		/* r1 <- symbol index in .dynsym */
 	add	r1, r10, r1		/* r1 <- address of symbol in table */
 	ldr	r1, [r1, #4]		/* r1 <- symbol value */
 	add	r1, r9			/* r1 <- relocated sym addr */
 	b	fixnext
 fixrel:
 	/* relative fix: increase location by offset */
 	ldr	r1, [r0]
 	add	r1, r1, r9
 fixnext:
 	str	r1, [r0]
 	add	r2, r2, #8		/* each rel.dyn entry is 8 bytes */
 	cmp	r2, r3
 	blo	fixloop
 #endif

 clear_bss:
 #ifndef CONFIG_PRELOADER
 	ldr	r0, _bss_start_ofs
 	ldr	r1, _bss_end_ofs
 	ldr	r3, _TEXT_BASE		/* Text base */
 	mov	r4, r6			/* reloc addr */
 	add	r0, r0, r4
 	add	r1, r1, r4
 	mov	r2, #0x00000000		/* clear			    */

 clbss_l:str	r2, [r0]		/* clear loop...		    */
 	add	r0, r0, #4
 	cmp	r0, r1
 	bne	clbss_l

 	bl coloured_LED_init
 	bl red_LED_on
 #endif

 /*
  * We are done. Do not return, instead branch to second part of board
  * initialization, now running from RAM.
  */
 	ldr	r0, _board_init_r_ofs
 	adr	r1, _start
 	add	lr, r0, r1
 	add	lr, lr, r9
 	/* setup parameters for board_init_r */
 	mov	r0, r5		/* gd_t */
 	mov	r1, r6		/* dest_addr */
 	/* jump to it ... */
 	mov	pc, lr

 _board_init_r_ofs:
 	.word board_init_r - _start

 _rel_dyn_start_ofs:
 	.word __rel_dyn_start - _start
 _rel_dyn_end_ofs:
 	.word __rel_dyn_end - _start
 _dynsym_start_ofs:
 	.word __dynsym_start - _start

 /*
  *************************************************************************
  *
  * CPU_init_critical registers
  *
  * setup important registers
  * setup memory timing
  *
  *************************************************************************
  */

 #define INTCON (0x01c00000+0x200000)
 #define INTMSK (0x01c00000+0x20000c)
 #define LOCKTIME (0x01c00000+0x18000c)
 #define PLLCON (0x01c00000+0x180000)
 #define CLKCON (0x01c00000+0x180004)
 #define WTCON (0x01c00000+0x130000)
 cpu_init_crit:
 	/* disable watch dog */
 	ldr	r0, =WTCON
 	ldr	r1, =0x0
 	str	r1, [r0]

 	/*
 	 * mask all IRQs by clearing all bits in the INTMRs
 	 */
 	ldr	r1,=INTMSK
 	ldr	r0, =0x03fffeff
 	str	r0, [r1]

 	ldr	r1, =INTCON
 	ldr	r0, =0x05
 	str	r0, [r1]

 	/* Set Clock Control Register */
 	ldr	r1, =LOCKTIME
 	ldrb	r0, =800
 	strb	r0, [r1]

 	ldr	r1, =PLLCON

 #if CONFIG_S3C44B0_CLOCK_SPEED==66
 	ldr	r0, =0x34031	/* 66MHz (Quartz=11MHz) */
 #elif CONFIG_S3C44B0_CLOCK_SPEED==75
 	ldr	r0, =0x610c1 /*B2: Xtal=20mhz Fclk=75MHz  */
 #else
 # error CONFIG_S3C44B0_CLOCK_SPEED undefined
 #endif

 	str	r0, [r1]

 	ldr	r1,=CLKCON
 	ldr	r0, =0x7ff8
 	str	r0, [r1]

 	mov	pc, lr


 /*************************************************/
 /*	interrupt vectors	*/
 /*************************************************/
 real_vectors:
 	b	reset
 	b	undefined_instruction
 	b	software_interrupt
 	b	prefetch_abort
 	b	data_abort
 	b	not_used
 	b	irq
 	b	fiq

 /*************************************************/

 undefined_instruction:
 	mov	r6, #3
 	b	reset

 software_interrupt:
 	mov	r6, #4
 	b	reset

 prefetch_abort:
 	mov	r6, #5
 	b	reset

 data_abort:
 	mov	r6, #6
 	b	reset

 not_used:
 	/* we *should* never reach this */
 	mov	r6, #7
 	b	reset

 irq:
 	mov	r6, #8
 	b	reset

 fiq:
 	mov	r6, #9
 	b	reset
	/*
	* Startup Code for S3C44B0 CPU-core
	*
	* (C) Copyright 2004
	* DAVE Srl
	*
	* http://www.dave-tech.it
	* http://www.wawnet.biz
	* mailto:info@wawnet.biz
	*
	* 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
	*/

	#include <asm-offsets.h>
	#include <config.h>
	#include <version.h>

	/*
	* Jump vector table
	*/


	.globl _start
	_start: b reset
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000
	add pc, pc, #0x0c000000

	.balignl 16,0xdeadbeef


	/*
	*************************************************************************
	*
	* Startup Code (reset vector)
	*
	* do important init only if we don't start from memory!
	* relocate u-boot to ram
	* setup stack
	* jump to second stage
	*
	*************************************************************************
	*/

	.globl _TEXT_BASE
	_TEXT_BASE:
	.word CONFIG_SYS_TEXT_BASE

	/*
	* These are defined in the board-specific linker script.
	* Subtracting _start from them lets the linker put their
	* relative position in the executable instead of leaving
	* them null.
	*/
	.globl _bss_start_ofs
	_bss_start_ofs:
	.word __bss_start - _start

	.globl _bss_end_ofs
	_bss_end_ofs:
	.word _end - _start

	#ifdef CONFIG_USE_IRQ
	/* IRQ stack memory (calculated at run-time) */
	.globl IRQ_STACK_START
	IRQ_STACK_START:
	.word 0x0badc0de

	/* IRQ stack memory (calculated at run-time) */
	.globl FIQ_STACK_START
	FIQ_STACK_START:
	.word 0x0badc0de
	#endif

	/* IRQ stack memory (calculated at run-time) + 8 bytes */
	.globl IRQ_STACK_START_IN
	IRQ_STACK_START_IN:
	.word 0x0badc0de

	/*
	* the actual reset code
	*/

	reset:
	/*
	* set the cpu to SVC32 mode
	*/
	mrs r0,cpsr
	bic r0,r0,#0x1f
	orr r0,r0,#0xd3
	msr cpsr,r0

	/*
	* we do sys-critical inits only at reboot,
	* not when booting from ram!
	*/
	#ifndef CONFIG_SKIP_LOWLEVEL_INIT
	bl cpu_init_crit
	/*
	* before relocating, we have to setup RAM timing
	* because memory timing is board-dependend, you will
	* find a lowlevel_init.S in your board directory.
	*/
	bl lowlevel_init
	#endif

	/* Set stackpointer in internal RAM to call board_init_f */
	call_board_init_f:
	ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
	bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
	ldr r0,=0x00000000
	bl board_init_f

	/------------------------------------------------------------------------------/

	/*
	* void relocate_code (addr_sp, gd, addr_moni)
	*
	* This "function" does not return, instead it continues in RAM
	* after relocating the monitor code.
	*
	*/
	.globl relocate_code
	relocate_code:
	mov r4, r0 /* save addr_sp */
	mov r5, r1 /* save addr of gd */
	mov r6, r2 /* save addr of destination */

	/* Set up the stack */
	stack_setup:
	mov sp, r4

	adr r0, _start
	cmp r0, r6
	beq clear_bss /* skip relocation */
	mov r1, r6 /* r1 <- scratch for copy_loop */
	ldr r2, _TEXT_BASE
	ldr r3, _bss_start_ofs
	add r2, r0, r3 /* r2 <- source end address */

	copy_loop:
	ldmia r0!, {r9-r10} /* copy from source address [r0] */
	stmia r1!, {r9-r10} /* copy to target address [r1] */
	cmp r0, r2 /* until source end address [r2] */
	blo copy_loop

	#ifndef CONFIG_PRELOADER
	/*
	* fix .rel.dyn relocations
	*/
	ldr r0, _TEXT_BASE /* r0 <- Text base */
	sub r9, r6, r0 /* r9 <- relocation offset */
	ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
	add r10, r10, r0 /* r10 <- sym table in FLASH */
	ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
	add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
	ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
	add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
	fixloop:
	ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
	add r0, r0, r9 /* r0 <- location to fix up in RAM */
	ldr r1, [r2, #4]
	and r8, r1, #0xff
	cmp r8, #23 /* relative fixup? */
	beq fixrel
	cmp r8, #2 /* absolute fixup? */
	beq fixabs
	/* ignore unknown type of fixup */
	b fixnext
	fixabs:
	/* absolute fix: set location to (offset) symbol value */
	mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
	add r1, r10, r1 /* r1 <- address of symbol in table */
	ldr r1, [r1, #4] /* r1 <- symbol value */
	add r1, r9 /* r1 <- relocated sym addr */
	b fixnext
	fixrel:
	/* relative fix: increase location by offset */
	ldr r1, [r0]
	add r1, r1, r9
	fixnext:
	str r1, [r0]
	add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
	cmp r2, r3
	blo fixloop
	#endif

	clear_bss:
	#ifndef CONFIG_PRELOADER
	ldr r0, _bss_start_ofs
	ldr r1, _bss_end_ofs
	ldr r3, _TEXT_BASE /* Text base */
	mov r4, r6 /* reloc addr */
	add r0, r0, r4
	add r1, r1, r4
	mov r2, #0x00000000 /* clear */

	clbss_l:str r2, [r0] /* clear loop... */
	add r0, r0, #4
	cmp r0, r1
	bne clbss_l

	bl coloured_LED_init
	bl red_LED_on
	#endif

	/*
	* We are done. Do not return, instead branch to second part of board
	* initialization, now running from RAM.
	*/
	ldr r0, _board_init_r_ofs
	adr r1, _start
	add lr, r0, r1
	add lr, lr, r9
	/* setup parameters for board_init_r */
	mov r0, r5 /* gd_t */
	mov r1, r6 /* dest_addr */
	/* jump to it ... */
	mov pc, lr

	_board_init_r_ofs:
	.word board_init_r - _start

	_rel_dyn_start_ofs:
	.word __rel_dyn_start - _start
	_rel_dyn_end_ofs:
	.word __rel_dyn_end - _start
	_dynsym_start_ofs:
	.word __dynsym_start - _start

	/*
	*************************************************************************
	*
	* CPU_init_critical registers
	*
	* setup important registers
	* setup memory timing
	*
	*************************************************************************
	*/

	#define INTCON (0x01c00000+0x200000)
	#define INTMSK (0x01c00000+0x20000c)
	#define LOCKTIME (0x01c00000+0x18000c)
	#define PLLCON (0x01c00000+0x180000)
	#define CLKCON (0x01c00000+0x180004)
	#define WTCON (0x01c00000+0x130000)
	cpu_init_crit:
	/* disable watch dog */
	ldr r0, =WTCON
	ldr r1, =0x0
	str r1, [r0]

	/*
	* mask all IRQs by clearing all bits in the INTMRs
	*/
	ldr r1,=INTMSK
	ldr r0, =0x03fffeff
	str r0, [r1]

	ldr r1, =INTCON
	ldr r0, =0x05
	str r0, [r1]

	/* Set Clock Control Register */
	ldr r1, =LOCKTIME
	ldrb r0, =800
	strb r0, [r1]

	ldr r1, =PLLCON

	#if CONFIG_S3C44B0_CLOCK_SPEED==66
	ldr r0, =0x34031 /* 66MHz (Quartz=11MHz) */
	#elif CONFIG_S3C44B0_CLOCK_SPEED==75
	ldr r0, =0x610c1 /B2: Xtal=20mhz Fclk=75MHz /
	#else
	# error CONFIG_S3C44B0_CLOCK_SPEED undefined
	#endif

	str r0, [r1]

	ldr r1,=CLKCON
	ldr r0, =0x7ff8
	str r0, [r1]

	mov pc, lr


	/*************************************************/
	/* interrupt vectors */
	/*************************************************/
	real_vectors:
	b reset
	b undefined_instruction
	b software_interrupt
	b prefetch_abort
	b data_abort
	b not_used
	b irq
	b fiq

	/*************************************************/

	undefined_instruction:
	mov r6, #3
	b reset

	software_interrupt:
	mov r6, #4
	b reset

	prefetch_abort:
	mov r6, #5
	b reset

	data_abort:
	mov r6, #6
	b reset

	not_used:
	/* we should never reach this */
	mov r6, #7
	b reset

	irq:
	mov r6, #8
	b reset

	fiq:
	mov r6, #9
	b reset