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+/*
+ * 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 <config.h>
+#include <asm/sysreg.h>
+
+#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