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authorSteve Sakoman <steve@sakoman.com>2010-06-17 21:50:01 -0700
committerSandeep Paulraj <s-paulraj@ti.com>2010-07-05 19:59:55 -0400
commitf56348af5d255f6dc2a8bcd7d798ab5edf8fba25 (patch)
tree5cb794b98d5d7bc0b8b8254a572b2171555c268c /arch/arm/cpu/armv7/start.S
parent8f22327a664acc886efc3f5362e6c375c82d5bcb (diff)
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ARM: Rename arch/arm/cpu/arm_cortexa8 to armv7
The purpose of this patch is to prepare for adding the OMAP4 architecture, which is Cortex A9 Cortex A8 and A9 both belong to the armv7 architecture, hence the name change. The two architectures are similar enough that substantial code can be shared. Signed-off-by: Aneesh V <aneesh@ti.com> Signed-off-by: Steve Sakoman <steve@sakoman.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
Diffstat (limited to 'arch/arm/cpu/armv7/start.S')
-rw-r--r--arch/arm/cpu/armv7/start.S416
1 files changed, 416 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S
new file mode 100644
index 0000000..1e0a150
--- /dev/null
+++ b/arch/arm/cpu/armv7/start.S
@@ -0,0 +1,416 @@
+/*
+ * armboot - Startup Code for OMAP3530/ARM Cortex CPU-core
+ *
+ * Copyright (c) 2004 Texas Instruments <r-woodruff2@ti.com>
+ *
+ * Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
+ * Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
+ * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
+ * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
+ * Copyright (c) 2003 Kshitij <kshitij@ti.com>
+ * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim@ti.com>
+ *
+ * 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 <config.h>
+#include <version.h>
+
+.globl _start
+_start: b reset
+ 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 */
+.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
+
+.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
+
+#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
+
+/*
+ * 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
+
+#if (CONFIG_OMAP34XX)
+ /* Copy vectors to mask ROM indirect addr */
+ adr r0, _start @ r0 <- current position of code
+ add r0, r0, #4 @ skip reset vector
+ mov r2, #64 @ r2 <- size to copy
+ add r2, r0, r2 @ r2 <- source end address
+ mov r1, #SRAM_OFFSET0 @ build vect addr
+ mov r3, #SRAM_OFFSET1
+ add r1, r1, r3
+ mov r3, #SRAM_OFFSET2
+ add r1, r1, r3
+next:
+ ldmia r0!, {r3 - r10} @ copy from source address [r0]
+ stmia r1!, {r3 - r10} @ copy to target address [r1]
+ cmp r0, r2 @ until source end address [r2]
+ bne next @ loop until equal */
+#if !defined(CONFIG_SYS_NAND_BOOT) && !defined(CONFIG_SYS_ONENAND_BOOT)
+ /* No need to copy/exec the clock code - DPLL adjust already done
+ * in NAND/oneNAND Boot.
+ */
+ bl cpy_clk_code @ put dpll adjust code behind vectors
+#endif /* NAND Boot */
+#endif
+ /* the mask ROM code should have PLL and others stable */
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+ bl cpu_init_crit
+#endif
+
+#ifndef CONFIG_SKIP_RELOCATE_UBOOT
+relocate: @ relocate U-Boot to RAM
+ adr r0, _start @ r0 <- current position of code
+ ldr r1, _TEXT_BASE @ test if we run from flash or RAM
+ cmp r0, r1 @ don't reloc during debug
+ beq stack_setup
+
+ ldr r2, _armboot_start
+ ldr r3, _bss_start
+ sub r2, r3, r2 @ r2 <- size of armboot
+ add r2, r0, r2 @ r2 <- source end address
+
+copy_loop: @ copy 32 bytes at a time
+ ldmia r0!, {r3 - r10} @ copy from source address [r0]
+ stmia r1!, {r3 - r10} @ copy to target address [r1]
+ cmp r0, r2 @ until source end addreee [r2]
+ ble copy_loop
+#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
+
+ /* Set up the stack */
+stack_setup:
+ ldr r0, _TEXT_BASE @ upper 128 KiB: relocated uboot
+ sub r0, r0, #CONFIG_SYS_MALLOC_LEN @ malloc area
+ sub r0, r0, #CONFIG_SYS_GBL_DATA_SIZE @ bdinfo
+#ifdef CONFIG_USE_IRQ
+ sub r0, r0, #(CONFIG_STACKSIZE_IRQ + CONFIG_STACKSIZE_FIQ)
+#endif
+ sub sp, r0, #12 @ leave 3 words for abort-stack
+ bic sp, sp, #7 @ 8-byte alignment for ABI compliance
+
+ /* Clear BSS (if any). Is below tx (watch load addr - need space) */
+clear_bss:
+ ldr r0, _bss_start @ find start of bss segment
+ ldr r1, _bss_end @ stop here
+ mov r2, #0x00000000 @ clear value
+clbss_l:
+ str r2, [r0] @ clear BSS location
+ cmp r0, r1 @ are we at the end yet
+ add r0, r0, #4 @ increment clear index pointer
+ bne clbss_l @ keep clearing till at end
+
+ ldr pc, _start_armboot @ jump to C code
+
+_start_armboot: .word start_armboot
+
+
+/*************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************/
+cpu_init_crit:
+ /*
+ * Invalidate L1 I/D
+ */
+ mov r0, #0 @ set up for MCR
+ mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate icache
+
+ /*
+ * disable MMU stuff and caches
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #0x00002000 @ clear bits 13 (--V-)
+ bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM)
+ orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align
+ orr r0, r0, #0x00000800 @ set bit 12 (Z---) BTB
+ mcr p15, 0, r0, c1, c0, 0
+
+ /*
+ * Jump to board specific initialization...
+ * The Mask ROM will have already initialized
+ * basic memory. Go here to bump up clock rate and handle
+ * wake up conditions.
+ */
+ mov ip, lr @ persevere link reg across call
+ bl lowlevel_init @ go setup pll,mux,memory
+ mov lr, ip @ restore link
+ mov pc, lr @ back to my caller
+/*
+ *************************************************************************
+ *
+ * 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 ...
+ * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
+ */
+
+ .macro bad_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current
+ @ user stack
+ stmia sp, {r0 - r12} @ Save user registers (now in
+ @ svc mode) r0-r12
+
+ ldr r2, _armboot_start
+ sub r2, r2, #(CONFIG_SYS_MALLOC_LEN)
+ sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ set base 2 words into abort
+ @ stack
+ ldmia r2, {r2 - r3} @ get values for "aborted" pc
+ @ and cpsr (into parm regs)
+ add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
+
+ add r5, sp, #S_SP
+ mov r1, lr
+ stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
+ mov r0, sp @ save current stack into r0
+ @ (param register)
+ .endm
+
+ .macro irq_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE
+ stmia sp, {r0 - r12} @ Calling r0-r12
+ add r8, sp, #S_PC @ !! R8 NEEDS to be saved !!
+ @ a reserved stack spot would
+ @ be good.
+ stmdb r8, {sp, lr}^ @ Calling SP, LR
+ str lr, [r8, #0] @ Save calling PC
+ mrs r6, spsr
+ str r6, [r8, #4] @ Save CPSR
+ str r0, [r8, #8] @ Save OLD_R0
+ mov r0, sp
+ .endm
+
+ .macro irq_restore_user_regs
+ ldmia sp, {r0 - lr}^ @ Calling r0 - lr
+ mov r0, r0
+ ldr lr, [sp, #S_PC] @ Get PC
+ add sp, sp, #S_FRAME_SIZE
+ subs pc, lr, #4 @ return & move spsr_svc into
+ @ cpsr
+ .endm
+
+ .macro get_bad_stack
+ ldr r13, _armboot_start @ setup our mode stack (enter
+ @ in banked mode)
+ sub r13, r13, #(CONFIG_SYS_MALLOC_LEN) @ move past malloc pool
+ sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ move to reserved a couple
+ @ spots for abort stack
+
+ str lr, [r13] @ save caller lr in position 0
+ @ of saved stack
+ mrs lr, spsr @ get the spsr
+ str lr, [r13, #4] @ save spsr in position 1 of
+ @ saved stack
+
+ mov r13, #MODE_SVC @ prepare SVC-Mode
+ @ msr spsr_c, r13
+ msr spsr, r13 @ switch modes, make sure
+ @ moves will execute
+ mov lr, pc @ capture return pc
+ movs pc, lr @ jump to next instruction &
+ @ switch modes.
+ .endm
+
+ .macro get_bad_stack_swi
+ sub r13, r13, #4 @ space on current stack for
+ @ scratch reg.
+ str r0, [r13] @ save R0's value.
+ ldr r0, _armboot_start @ get data regions start
+ sub r0, r0, #(CONFIG_SYS_MALLOC_LEN) @ move past malloc pool
+ sub r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ move past gbl and a couple
+ @ spots for abort stack
+ str lr, [r0] @ save caller lr in position 0
+ @ of saved stack
+ mrs r0, spsr @ get the spsr
+ str lr, [r0, #4] @ save spsr in position 1 of
+ @ saved stack
+ ldr r0, [r13] @ restore r0
+ add r13, r13, #4 @ pop stack entry
+ .endm
+
+ .macro get_irq_stack @ setup IRQ stack
+ ldr sp, IRQ_STACK_START
+ .endm
+
+ .macro get_fiq_stack @ setup FIQ stack
+ ldr sp, FIQ_STACK_START
+ .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
+
+#ifdef CONFIG_USE_IRQ
+
+ .align 5
+irq:
+ get_irq_stack
+ irq_save_user_regs
+ bl do_irq
+ irq_restore_user_regs
+
+ .align 5
+fiq:
+ get_fiq_stack
+ /* someone ought to write a more effective fiq_save_user_regs */
+ irq_save_user_regs
+ bl do_fiq
+ irq_restore_user_regs
+
+#else
+
+ .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