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+/*
+ * armboot - Startup Code for ARM720 CPU-core
+ *
+ * Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
+ * Copyright (c) 2002 Alex Züpke <azu@sysgo.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
+ */
+
+
+#include <config.h>
+#include <version.h>
+#include <asm/hardware.h>
+
+/*
+ *************************************************************************
+ *
+ * Jump vector table as in table 3.1 in [1]
+ *
+ *************************************************************************
+ */
+
+
+.globl _start
+_start: b reset
+ ldr pc, _undefined_instruction
+ ldr pc, _software_interrupt
+ ldr pc, _prefetch_abort
+ ldr pc, _data_abort
+#ifdef CONFIG_LPC2292
+ .word 0xB4405F76 /* 2's complement of the checksum of the vectors */
+#else
+ ldr pc, _not_used
+#endif
+ 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
+
+ .balignl 16,0xdeadbeef
+
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from RAM!
+ * relocate armboot to ram
+ * setup stack
+ * jump to second stage
+ *
+ *************************************************************************
+ */
+
+_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,#0x13
+ 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
+#endif
+
+#ifdef CONFIG_LPC2292
+ bl lowlevel_init
+#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
+
+#if TEXT_BASE
+#ifndef CONFIG_LPC2292 /* already done in lowlevel_init */
+ ldr r2, =0x0 /* Relocate the exception vectors */
+ cmp r1, r2 /* and associated data to address */
+ ldmneia r0!, {r3-r10} /* 0x0. Do nothing if TEXT_BASE is */
+ stmneia r2!, {r3-r10} /* 0x0. Copy the first 15 words. */
+ ldmneia r0, {r3-r9}
+ stmneia r2, {r3-r9}
+ adrne r0, _start /* restore r0 */
+#endif /* !CONFIG_LPC2292 */
+#endif
+
+ 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:
+ 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 */
+
+clear_bss:
+ ldr r0, _bss_start /* find start of bss segment */
+ ldr r1, _bss_end /* stop here */
+ mov r2, #0x00000000 /* clear */
+
+clbss_l:str r2, [r0] /* clear loop... */
+ add r0, r0, #4
+ cmp r0, r1
+ ble clbss_l
+
+ ldr pc, _start_armboot
+
+_start_armboot: .word start_armboot
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+
+#if defined(CONFIG_IMPA7) || defined(CONFIG_EP7312) || defined(CONFIG_ARMADILLO)
+
+/* Interupt-Controller base addresses */
+INTMR1: .word 0x80000280 @ 32 bit size
+INTMR2: .word 0x80001280 @ 16 bit size
+INTMR3: .word 0x80002280 @ 8 bit size
+
+/* SYSCONs */
+SYSCON1: .word 0x80000100
+SYSCON2: .word 0x80001100
+SYSCON3: .word 0x80002200
+
+#define CLKCTL 0x6 /* mask */
+#define CLKCTL_18 0x0 /* 18.432 MHz */
+#define CLKCTL_36 0x2 /* 36.864 MHz */
+#define CLKCTL_49 0x4 /* 49.152 MHz */
+#define CLKCTL_73 0x6 /* 73.728 MHz */
+
+#elif defined(CONFIG_LPC2292)
+PLLCFG_ADR: .word PLLCFG
+PLLFEED_ADR: .word PLLFEED
+PLLCON_ADR: .word PLLCON
+PLLSTAT_ADR: .word PLLSTAT
+VPBDIV_ADR: .word VPBDIV
+MEMMAP_ADR: .word MEMMAP
+
+#endif
+
+cpu_init_crit:
+#if defined(CONFIG_IMPA7) || defined(CONFIG_EP7312) || defined(CONFIG_ARMADILLO)
+
+ /*
+ * mask all IRQs by clearing all bits in the INTMRs
+ */
+ mov r1, #0x00
+ ldr r0, INTMR1
+ str r1, [r0]
+ ldr r0, INTMR2
+ str r1, [r0]
+ ldr r0, INTMR3
+ str r1, [r0]
+
+ /*
+ * 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
+ bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
+ bic r0, r0, #0x0000008f @ clear bits 7, 3:0 (B--- WCAM)
+ orr r0, r0, #0x00000002 @ set bit 2 (A) Align
+ mcr p15,0,r0,c1,c0
+#elif defined(CONFIG_NETARM)
+ /*
+ * prior to software reset : need to set pin PORTC4 to be *HRESET
+ */
+ ldr r0, =NETARM_GEN_MODULE_BASE
+ ldr r1, =(NETARM_GEN_PORT_MODE(0x10) | \
+ NETARM_GEN_PORT_DIR(0x10))
+ str r1, [r0, #+NETARM_GEN_PORTC]
+ /*
+ * software reset : see HW Ref. Guide 8.2.4 : Software Service register
+ * for an explanation of this process
+ */
+ ldr r0, =NETARM_GEN_MODULE_BASE
+ ldr r1, =NETARM_GEN_SW_SVC_RESETA
+ str r1, [r0, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETB
+ str r1, [r0, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETA
+ str r1, [r0, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETB
+ str r1, [r0, #+NETARM_GEN_SOFTWARE_SERVICE]
+ /*
+ * setup PLL and System Config
+ */
+ ldr r0, =NETARM_GEN_MODULE_BASE
+
+ ldr r1, =( NETARM_GEN_SYS_CFG_LENDIAN | \
+ NETARM_GEN_SYS_CFG_BUSFULL | \
+ NETARM_GEN_SYS_CFG_USER_EN | \
+ NETARM_GEN_SYS_CFG_ALIGN_ABORT | \
+ NETARM_GEN_SYS_CFG_BUSARB_INT | \
+ NETARM_GEN_SYS_CFG_BUSMON_EN )
+
+ str r1, [r0, #+NETARM_GEN_SYSTEM_CONTROL]
+
+#ifndef CONFIG_NETARM_PLL_BYPASS
+ ldr r1, =( NETARM_GEN_PLL_CTL_PLLCNT(NETARM_PLL_COUNT_VAL) | \
+ NETARM_GEN_PLL_CTL_POLTST_DEF | \
+ NETARM_GEN_PLL_CTL_INDIV(1) | \
+ NETARM_GEN_PLL_CTL_ICP_DEF | \
+ NETARM_GEN_PLL_CTL_OUTDIV(2) )
+ str r1, [r0, #+NETARM_GEN_PLL_CONTROL]
+#endif
+
+ /*
+ * mask all IRQs by clearing all bits in the INTMRs
+ */
+ mov r1, #0
+ ldr r0, =NETARM_GEN_MODULE_BASE
+ str r1, [r0, #+NETARM_GEN_INTR_ENABLE]
+
+#elif defined(CONFIG_S3C4510B)
+
+ /*
+ * Mask off all IRQ sources
+ */
+ ldr r1, =REG_INTMASK
+ ldr r0, =0x3FFFFF
+ str r0, [r1]
+
+ /*
+ * Disable Cache
+ */
+ ldr r0, =REG_SYSCFG
+ ldr r1, =0x83ffffa0 /* cache-disabled */
+ str r1, [r0]
+
+#elif defined(CONFIG_INTEGRATOR) && defined(CONFIG_ARCH_INTEGRATOR)
+ /* No specific initialisation for IntegratorAP/CM720T as yet */
+#elif defined(CONFIG_LPC2292)
+ /* Set-up PLL */
+ mov r3, #0xAA
+ mov r4, #0x55
+ /* First disconnect and disable the PLL */
+ ldr r0, PLLCON_ADR
+ mov r1, #0x00
+ str r1, [r0]
+ ldr r0, PLLFEED_ADR /* start feed sequence */
+ str r3, [r0]
+ str r4, [r0] /* feed sequence done */
+ /* Set new M and P values */
+ ldr r0, PLLCFG_ADR
+ mov r1, #0x23 /* M=4 and P=2 */
+ str r1, [r0]
+ ldr r0, PLLFEED_ADR /* start feed sequence */
+ str r3, [r0]
+ str r4, [r0] /* feed sequence done */
+ /* Then enable the PLL */
+ ldr r0, PLLCON_ADR
+ mov r1, #0x01 /* PLL enable bit */
+ str r1, [r0]
+ ldr r0, PLLFEED_ADR /* start feed sequence */
+ str r3, [r0]
+ str r4, [r0] /* feed sequence done */
+ /* Wait for the lock */
+ ldr r0, PLLSTAT_ADR
+ mov r1, #0x400 /* lock bit */
+lock_loop:
+ ldr r2, [r0]
+ and r2, r1, r2
+ cmp r2, #0
+ beq lock_loop
+ /* And finally connect the PLL */
+ ldr r0, PLLCON_ADR
+ mov r1, #0x03 /* PLL enable bit and connect bit */
+ str r1, [r0]
+ ldr r0, PLLFEED_ADR /* start feed sequence */
+ str r3, [r0]
+ str r4, [r0] /* feed sequence done */
+ /* Set-up VPBDIV register */
+ ldr r0, VPBDIV_ADR
+ mov r1, #0x01 /* VPB clock is same as process clock */
+ str r1, [r0]
+#else
+#error No cpu_init_crit() defined for current CPU type
+#endif
+
+#ifdef CONFIG_ARM7_REVD
+ /* set clock speed */
+ /* !!! we run @ 36 MHz due to a hardware flaw in Rev. D processors */
+ /* !!! not doing DRAM refresh properly! */
+ ldr r0, SYSCON3
+ ldr r1, [r0]
+ bic r1, r1, #CLKCTL
+ orr r1, r1, #CLKCTL_36
+ str r1, [r0]
+#endif
+
+#ifndef CONFIG_LPC2292
+ mov ip, lr
+ /*
+ * before relocating, we have to setup RAM timing
+ * because memory timing is board-dependent, you will
+ * find a lowlevel_init.S in your board directory.
+ */
+ bl lowlevel_init
+ mov lr, ip
+#endif
+
+ mov pc, lr
+
+
+/*
+ *************************************************************************
+ *
+ * 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
+ stmia sp, {r0 - r12} @ Calling r0-r12
+ add r8, sp, #S_PC
+
+ ldr r2, _armboot_start
+ sub r2, r2, #(CONFIG_STACKSIZE+CONFIG_SYS_MALLOC_LEN)
+ sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8) @ set base 2 words into abort stack
+ ldmia r2, {r2 - r4} @ get pc, cpsr, old_r0
+ add r0, sp, #S_FRAME_SIZE @ restore sp_SVC
+
+ add r5, sp, #S_SP
+ mov r1, lr
+ stmia r5, {r0 - r4} @ save sp_SVC, lr_SVC, pc, cpsr, old_r
+ mov r0, sp
+ .endm
+
+ .macro irq_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE
+ stmia sp, {r0 - r12} @ Calling r0-r12
+ add r8, sp, #S_PC
+ 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
+ sub r13, r13, #(CONFIG_STACKSIZE+CONFIG_SYS_MALLOC_LEN)
+ sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE+8) @ reserved a couple spots in abort stack
+
+ str lr, [r13] @ save caller lr / spsr
+ mrs lr, spsr
+ str lr, [r13, #4]
+
+ mov r13, #MODE_SVC @ prepare SVC-Mode
+ msr spsr_c, r13
+ mov lr, pc
+ movs pc, lr
+ .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
+ 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 effiction 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
+
+#if defined(CONFIG_IMPA7) || defined(CONFIG_EP7312) || defined(CONFIG_ARMADILLO)
+ .align 5
+.globl reset_cpu
+reset_cpu:
+ mov ip, #0
+ mcr p15, 0, ip, c7, c7, 0 @ invalidate cache
+ mcr p15, 0, ip, c8, c7, 0 @ flush TLB (v4)
+ mrc p15, 0, ip, c1, c0, 0 @ get ctrl register
+ bic ip, ip, #0x000f @ ............wcam
+ bic ip, ip, #0x2100 @ ..v....s........
+ mcr p15, 0, ip, c1, c0, 0 @ ctrl register
+ mov pc, r0
+#elif defined(CONFIG_NETARM)
+ .align 5
+.globl reset_cpu
+reset_cpu:
+ ldr r1, =NETARM_MEM_MODULE_BASE
+ ldr r0, [r1, #+NETARM_MEM_CS0_BASE_ADDR]
+ ldr r1, =0xFFFFF000
+ and r0, r1, r0
+ ldr r1, =(relocate-TEXT_BASE)
+ add r0, r1, r0
+ ldr r4, =NETARM_GEN_MODULE_BASE
+ ldr r1, =NETARM_GEN_SW_SVC_RESETA
+ str r1, [r4, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETB
+ str r1, [r4, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETA
+ str r1, [r4, #+NETARM_GEN_SOFTWARE_SERVICE]
+ ldr r1, =NETARM_GEN_SW_SVC_RESETB
+ str r1, [r4, #+NETARM_GEN_SOFTWARE_SERVICE]
+ mov pc, r0
+#elif defined(CONFIG_S3C4510B)
+/* Nothing done here as reseting the CPU is board specific, depending
+ * on external peripherals such as watchdog timers, etc. */
+#elif defined(CONFIG_INTEGRATOR) && defined(CONFIG_ARCH_INTEGRATOR)
+ /* No specific reset actions for IntegratorAP/CM720T as yet */
+#elif defined(CONFIG_LPC2292)
+ .align 5
+.globl reset_cpu
+reset_cpu:
+ mov pc, r0
+#else
+#error No reset_cpu() defined for current CPU type
+#endif