ARM: Add arm1176 core with S3C6400 SoC

Based on the original S3C64XX port by Samsung for U-Boot 1.1.6.

Signed-off-by: Guennadi Liakhovetski <lg@denx.de>

1 files changed, 469 insertions, 0 deletions

diff --git a/cpu/arm1176/start.S b/cpu/arm1176/start.S
new file mode 100644
index 0000000..991277f
--- /dev/null
+++ b/cpu/arm1176/start.S
@@ -0,0 +1,469 @@
+/*
+ *  armboot - Startup Code for S3C6400/ARM1176 CPU-core
+ *
+ * Copyright (c) 2007	Samsung Electronics
+ *
+ * Copyright (C) 2008
+ * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
+ *
+ * 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
+ *
+ * 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
+ * 2007-09-21 - Added MoviNAND and OneNAND boot codes by
+ * jsgood (jsgood.yang@samsung.com)
+ * Base codes by scsuh (sc.suh)
+ */
+
+#include <config.h>
+#include <version.h>
+#ifdef CONFIG_ENABLE_MMU
+#include <asm/proc/domain.h>
+#endif
+#include <s3c6400.h>
+
+#if !defined(CONFIG_ENABLE_MMU) && !defined(CFG_PHY_UBOOT_BASE)
+#define CFG_PHY_UBOOT_BASE	CFG_UBOOT_BASE
+#endif
+
+/*
+ *************************************************************************
+ *
+ * Jump vector table as in table 3.1 in [1]
+ *
+ *************************************************************************
+ */
+
+.globl _start
+_start: b	reset
+#ifndef CONFIG_NAND_SPL
+	ldr	pc, _undefined_instruction
+	ldr	pc, _software_interrupt
+	ldr	pc, _prefetch_abort
+	ldr	pc, _data_abort
+	ldr	pc, _not_used
+	ldr	pc, _irq
+	ldr	pc, _fiq
+
+_undefined_instruction:
+	.word undefined_instruction
+_software_interrupt:
+	.word software_interrupt
+_prefetch_abort:
+	.word prefetch_abort
+_data_abort:
+	.word data_abort
+_not_used:
+	.word not_used
+_irq:
+	.word irq
+_fiq:
+	.word fiq
+_pad:
+	.word 0x12345678 /* now 16*4=64 */
+#else
+	. = _start + 64
+#endif
+
+.global _end_vect
+_end_vect:
+	.balignl 16,0xdeadbeef
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * setup Memory and board specific bits prior to relocation.
+ * relocate armboot to ram
+ * setup stack
+ *
+ *************************************************************************
+ */
+
+_TEXT_BASE:
+	.word	TEXT_BASE
+
+/*
+ * Below variable is very important because we use MMU in U-Boot.
+ * Without it, we cannot run code correctly before MMU is ON.
+ * by scsuh.
+ */
+_TEXT_PHY_BASE:
+	.word	CFG_PHY_UBOOT_BASE
+
+.globl _armboot_start
+_armboot_start:
+	.word _start
+
+/*
+ * These are defined in the board-specific linker script.
+ */
+.globl _bss_start
+_bss_start:
+	.word __bss_start
+
+.globl _bss_end
+_bss_end:
+	.word _end
+
+/*
+ * the actual reset code
+ */
+
+reset:
+	/*
+	 * set the cpu to SVC32 mode
+	 */
+	mrs	r0, cpsr
+	bic	r0, r0, #0x3f
+	orr	r0, r0, #0xd3
+	msr	cpsr, r0
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+	/*
+	 * we do sys-critical inits only at reboot,
+	 * not when booting from ram!
+	 */
+cpu_init_crit:
+	/*
+	 * When booting from NAND - it has definitely been a reset, so, no need
+	 * to flush caches and disable the MMU
+	 */
+#ifndef CONFIG_NAND_SPL
+	/*
+	 * flush v4 I/D caches
+	 */
+	mov	r0, #0
+	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
+	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
+
+	/*
+	 * disable MMU stuff and caches
+	 */
+	mrc	p15, 0, r0, c1, c0, 0
+	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
+	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
+	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
+	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
+	/* Prepare to disable the MMU */
+	adr	r1, mmu_disable_phys
+	/* We presume we're within the first 1024 bytes */
+	and	r1, r1, #0x3fc
+	ldr	r2, _TEXT_PHY_BASE
+	ldr	r3, =0xfff00000
+	and	r2, r2, r3
+	orr	r2, r2, r1
+	b	mmu_disable
+
+	.align 5
+	/* Run in a single cache-line */
+mmu_disable:
+	mcr	p15, 0, r0, c1, c0, 0
+	nop
+	nop
+	mov	pc, r2
+#endif
+
+mmu_disable_phys:
+	/* Peri port setup */
+	ldr	r0, =0x70000000
+	orr	r0, r0, #0x13
+	mcr	p15,0,r0,c15,c2,4       @ 256M (0x70000000 - 0x7fffffff)
+
+	/*
+	 * Go setup Memory and board specific bits prior to relocation.
+	 */
+	bl	lowlevel_init		/* go setup pll,mux,memory */
+
+after_copy:
+#ifdef CONFIG_ENABLE_MMU
+enable_mmu:
+	/* enable domain access */
+	ldr	r5, =0x0000ffff
+	mcr	p15, 0, r5, c3, c0, 0	/* load domain access register */
+
+	/* Set the TTB register */
+	ldr	r0, _mmu_table_base
+	ldr	r1, =CFG_PHY_UBOOT_BASE
+	ldr	r2, =0xfff00000
+	bic	r0, r0, r2
+	orr	r1, r0, r1
+	mcr	p15, 0, r1, c2, c0, 0
+
+	/* Enable the MMU */
+	mrc	p15, 0, r0, c1, c0, 0
+	orr	r0, r0, #1		/* Set CR_M to enable MMU */
+
+	/* Prepare to enable the MMU */
+	adr	r1, skip_hw_init
+	and	r1, r1, #0x3fc
+	ldr	r2, _TEXT_BASE
+	ldr	r3, =0xfff00000
+	and	r2, r2, r3
+	orr	r2, r2, r1
+	b	mmu_enable
+
+	.align 5
+	/* Run in a single cache-line */
+mmu_enable:
+
+	mcr	p15, 0, r0, c1, c0, 0
+	nop
+	nop
+	mov	pc, r2
+#endif
+
+skip_hw_init:
+	/* Set up the stack						    */
+stack_setup:
+#ifdef CONFIG_MEMORY_UPPER_CODE
+	ldr	sp, =(CFG_UBOOT_BASE + CFG_UBOOT_SIZE - 0xc)
+#else
+	ldr	r0, _TEXT_BASE		/* upper 128 KiB: relocated uboot   */
+	sub	r0, r0, #CFG_MALLOC_LEN	/* malloc area                      */
+	sub	r0, r0, #CFG_GBL_DATA_SIZE /* bdinfo                        */
+	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
+
+#endif
+
+clear_bss:
+	ldr	r0, _bss_start		/* find start of bss segment        */
+	ldr	r1, _bss_end		/* stop here                        */
+	mov 	r2, #0			/* clear                            */
+
+clbss_l:
+	str	r2, [r0]		/* clear loop...                    */
+	add	r0, r0, #4
+	cmp	r0, r1
+	ble	clbss_l
+
+#ifndef CONFIG_NAND_SPL
+	ldr	pc, _start_armboot
+
+_start_armboot:
+	.word start_armboot
+#else
+	b	nand_boot
+/*	.word nand_boot*/
+#endif
+
+#ifdef CONFIG_ENABLE_MMU
+_mmu_table_base:
+	.word mmu_table
+#endif
+
+#ifndef CONFIG_NAND_SPL
+/*
+ * we assume that cache operation is done before. (eg. cleanup_before_linux())
+ * actually, we don't need to do anything about cache if not use d-cache in
+ * U-Boot. So, in this function we clean only MMU. by scsuh
+ *
+ * void	theLastJump(void *kernel, int arch_num, uint boot_params);
+ */
+#ifdef CONFIG_ENABLE_MMU
+	.globl theLastJump
+theLastJump:
+	mov	r9, r0
+	ldr	r3, =0xfff00000
+	ldr	r4, _TEXT_PHY_BASE
+	adr	r5, phy_last_jump
+	bic	r5, r5, r3
+	orr	r5, r5, r4
+	mov	pc, r5
+phy_last_jump:
+	/*
+	 * disable MMU stuff
+	 */
+	mrc	p15, 0, r0, c1, c0, 0
+	bic	r0, r0, #0x00002300	/* clear bits 13, 9:8 (--V- --RS) */
+	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
+	orr	r0, r0, #0x00000002	/* set bit 2 (A) Align */
+	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
+	mcr	p15, 0, r0, c1, c0, 0
+
+	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
+
+	mov	r0, #0
+	mov	pc, r9
+#endif
+/*
+ *************************************************************************
+ *
+ * Interrupt handling
+ *
+ *************************************************************************
+ */
+@
+@ IRQ stack frame.
+@
+#define S_FRAME_SIZE	72
+
+#define S_OLD_R0	68
+#define S_PSR		64
+#define S_PC		60
+#define S_LR		56
+#define S_SP		52
+
+#define S_IP		48
+#define S_FP		44
+#define S_R10		40
+#define S_R9		36
+#define S_R8		32
+#define S_R7		28
+#define S_R6		24
+#define S_R5		20
+#define S_R4		16
+#define S_R3		12
+#define S_R2		8
+#define S_R1		4
+#define S_R0		0
+
+#define MODE_SVC 0x13
+#define I_BIT	 0x80
+
+/*
+ * use bad_save_user_regs for abort/prefetch/undef/swi ...
+ */
+
+	.macro	bad_save_user_regs
+	/* carve out a frame on current user stack */
+	sub	sp, sp, #S_FRAME_SIZE
+	/* Save user registers (now in svc mode) r0-r12 */
+	stmia	sp, {r0 - r12}
+
+	ldr	r2, _armboot_start
+	sub	r2, r2, #(CFG_MALLOC_LEN)
+	/* set base 2 words into abort stack */
+	sub	r2, r2, #(CFG_GBL_DATA_SIZE+8)
+	/* get values for "aborted" pc and cpsr (into parm regs) */
+	ldmia	r2, {r2 - r3}
+	/* grab pointer to old stack */
+	add	r0, sp, #S_FRAME_SIZE
+
+	add	r5, sp, #S_SP
+	mov	r1, lr
+	/* save sp_SVC, lr_SVC, pc, cpsr */
+	stmia	r5, {r0 - r3}
+	/* save current stack into r0 (param register) */
+	mov	r0, sp
+	.endm
+
+	.macro get_bad_stack
+	/* setup our mode stack (enter in banked mode) */
+	ldr	r13, _armboot_start
+	/* move past malloc pool */
+	sub	r13, r13, #(CFG_MALLOC_LEN)
+	/* move to reserved a couple spots for abort stack */
+	sub	r13, r13, #(CFG_GBL_DATA_SIZE + 8)
+
+	/* save caller lr in position 0 of saved stack */
+	str	lr, [r13]
+	/* get the spsr */
+	mrs	lr, spsr
+	/* save spsr in position 1 of saved stack */
+	str	lr, [r13, #4]
+
+	/* prepare SVC-Mode */
+	mov	r13, #MODE_SVC
+	@ msr	spsr_c, r13
+	/* switch modes, make sure moves will execute */
+	msr	spsr, r13
+	/* capture return pc */
+	mov	lr, pc
+	/* jump to next instruction & switch modes. */
+	movs	pc, lr
+	.endm
+
+	.macro get_bad_stack_swi
+	/* space on current stack for scratch reg. */
+	sub	r13, r13, #4
+	/* save R0's value. */
+	str	r0, [r13]
+	/* get data regions start */
+	ldr	r0, _armboot_start
+	/* move past malloc pool */
+	sub	r0, r0, #(CFG_MALLOC_LEN)
+	/* move past gbl and a couple spots for abort stack */
+	sub	r0, r0, #(CFG_GBL_DATA_SIZE + 8)
+	/* save caller lr in position 0 of saved stack */
+	str	lr, [r0]
+	/* get the spsr */
+	mrs	r0, spsr
+	/* save spsr in position 1 of saved stack */
+	str	lr, [r0, #4]
+	/* restore r0 */
+	ldr	r0, [r13]
+	/* pop stack entry */
+	add	r13, r13, #4
+	.endm
+
+/*
+ * exception handlers
+ */
+	.align	5
+undefined_instruction:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_undefined_instruction
+
+	.align	5
+software_interrupt:
+	get_bad_stack_swi
+	bad_save_user_regs
+	bl	do_software_interrupt
+
+	.align	5
+prefetch_abort:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_prefetch_abort
+
+	.align	5
+data_abort:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_data_abort
+
+	.align	5
+not_used:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_not_used
+
+	.align	5
+irq:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_irq
+
+	.align	5
+fiq:
+	get_bad_stack
+	bad_save_user_regs
+	bl	do_fiq
+#endif /* CONFIG_NAND_SPL */