/* * Copyright (C) 2005-2006 Atmel Corporation * * 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 #include #ifndef PART_SPECIFIC_BOOTSTRAP # define PART_SPECIFIC_BOOTSTRAP #endif #define SYSREG_MMUCR_I_OFFSET 2 #define SYSREG_MMUCR_S_OFFSET 4 #define SR_INIT (SYSREG_BIT(GM) | SYSREG_BIT(EM) | SYSREG_BIT(M0)) #define CPUCR_INIT (SYSREG_BIT(BI) | SYSREG_BIT(BE) \ | SYSREG_BIT(FE) | SYSREG_BIT(RE) \ | SYSREG_BIT(IBE) | SYSREG_BIT(IEE)) .text .global _start _start: PART_SPECIFIC_BOOTSTRAP /* Reset the Status Register */ mov r0, lo(SR_INIT) orh r0, hi(SR_INIT) mtsr SYSREG_SR, r0 /* Reset CPUCR and invalidate the BTB */ mov r2, CPUCR_INIT mtsr SYSREG_CPUCR, r2 /* Flush the caches */ mov r1, 0 cache r1[4], 8 cache r1[0], 0 sync 0 /* Reset the MMU to default settings */ mov r0, SYSREG_BIT(MMUCR_S) | SYSREG_BIT(MMUCR_I) mtsr SYSREG_MMUCR, r0 /* Internal RAM should not need any initialization. We might have to initialize external RAM here if the part doesn't have internal RAM (or we may use the data cache) */ /* Jump to cacheable segment */ lddpc pc, 1f .align 2 1: .long 2f 2: lddpc sp, sp_init /* * Relocate the data section and initialize .bss. Everything * is guaranteed to be at least doubleword aligned by the * linker script. */ lddpc r12, .Ldata_vma lddpc r11, .Ldata_lma lddpc r10, .Ldata_end sub r10, r12 4: ld.d r8, r11++ sub r10, 8 st.d r12++, r8 brne 4b mov r8, 0 mov r9, 0 lddpc r10, .Lbss_end sub r10, r12 4: sub r10, 8 st.d r12++, r8 brne 4b /* Initialize the GOT pointer */ lddpc r6, got_init 3: rsub r6, pc ld.w pc, r6[start_u_boot@got] .align 2 .type sp_init,@object sp_init: .long CFG_INIT_SP_ADDR got_init: .long 3b - _GLOBAL_OFFSET_TABLE_ .Ldata_lma: .long __data_lma .Ldata_vma: .long _data .Ldata_end: .long _edata .Lbss_end: .long _end