--- /dev/null
+/*
+ * armboot - Startup Code for SA1100 CPU
+ *
+ * Copyright (C) 1998 Dan Malek <dmalek@jlc.net>
+ * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
+ * Copyright (C) 2000 Wolfgang Denk <wd@denx.de>
+ * Copyright (c) 2001 Alex Züpke <azu@sysgo.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <version.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
+ 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
+
+ .balignl 16,0xdeadbeef
+
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * relocate armboot to ram
+ * setup stack
+ * jump to second stage
+ *
+ *************************************************************************
+ */
+
+#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
+#endif
+
+ bl _main
+
+/*------------------------------------------------------------------------------*/
+
+ .globl c_runtime_cpu_setup
+c_runtime_cpu_setup:
+
+ mov pc, lr
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+
+
+/* Interrupt-Controller base address */
+IC_BASE: .word 0x90050000
+#define ICMR 0x04
+
+
+/* Reset-Controller */
+RST_BASE: .word 0x90030000
+#define RSRR 0x00
+#define RCSR 0x04
+
+
+/* PWR */
+PWR_BASE: .word 0x90020000
+#define PSPR 0x08
+#define PPCR 0x14
+cpuspeed: .word CONFIG_SYS_CPUSPEED
+
+
+cpu_init_crit:
+ /*
+ * mask all IRQs
+ */
+ ldr r0, IC_BASE
+ mov r1, #0x00
+ str r1, [r0, #ICMR]
+
+ /* set clock speed */
+ ldr r0, PWR_BASE
+ ldr r1, cpuspeed
+ str r1, [r0, #PPCR]
+
+ /*
+ * 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.
+ */
+ mov ip, lr
+ bl lowlevel_init
+ mov lr, ip
+
+ /*
+ * disable MMU stuff and enable I-cache
+ */
+ mrc p15,0,r0,c1,c0
+ bic r0, r0, #0x00002000 @ clear bit 13 (X)
+ bic r0, r0, #0x0000000f @ clear bits 3-0 (WCAM)
+ orr r0, r0, #0x00001000 @ set bit 12 (I) Icache
+ orr r0, r0, #0x00000002 @ set bit 2 (A) Align
+ mcr p15,0,r0,c1,c0
+
+ /*
+ * 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 */
+
+ 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, IRQ_STACK_START_IN
+ 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, IRQ_STACK_START_IN @ setup our mode 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
+
+ .align 5
+.globl reset_cpu
+reset_cpu:
+ ldr r0, RST_BASE
+ mov r1, #0x0 @ set bit 3-0 ...
+ str r1, [r0, #RCSR] @ ... to clear in RCSR
+ mov r1, #0x1
+ str r1, [r0, #RSRR] @ and perform reset
+ b reset_cpu @ silly, but repeat endlessly
Code Review / kvmfornfv.git / blobdiff