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authorGuennadi Liakhovetski <lg@denx.de>2008-08-31 00:39:46 +0200
committerJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>2008-08-31 00:39:46 +0200
commit9b07773f8883665b002500c190507e9fd99b7181 (patch)
tree5efa1c039073cd50da97671f9da6bcbe908f5746 /cpu/arm1176/start.S
parentfcaac589a68115819ddadcf5c18ded9a5f9e2c75 (diff)
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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>
Diffstat (limited to 'cpu/arm1176/start.S')
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1 files changed, 469 insertions, 0 deletions
diff --git a/cpu/arm1176/start.S b/cpu/arm1176/start.S
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+/*
+ * 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 */