+++ /dev/null
-/*
- * (C) Copyright 2003, Psyent Corporation <www.psyent.com>
- * Scott McNutt <smcnutt@psyent.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 <timestamp.h>
-#include <version.h>
-
-#if !defined(CONFIG_IDENT_STRING)
-#define CONFIG_IDENT_STRING ""
-#endif
-
-#define STATUS_INIT 0x8600 /* IE=1, IPRI=2 */
-
-/*************************************************************************
- * RESTART
- ************************************************************************/
-
- .text
- .global _start
-
-_start:
- bsr 0f
- nop
- .long _start
-
- /* GERMS -- The "standard-32" configuration GERMS monitor looks
- * for the string "Nios" at flash_base + 0xc (actually it only
- * tests for 'N', 'i'). You can leave support for this in place
- * as it's only a few words.
- */
- . = _start + 0x000c
- .string "Nios"
-
- .align 4
-0:
- /*
- * Early setup -- set cwp = HI_LIMIT, IPRI = 2, IE = 1 to
- * enable underflow exceptions. Disable cache.
- * NOTE: %o7 has return addr -- save in %g7 use later.
- */
- mov %g7, %o7
-
- pfx 2 /* WVALID */
- rdctl %g0
- lsri %g0, 1
- pfx %hi(STATUS_INIT)
- or %g0, %lo(STATUS_INIT)
- wrctl %g0 /* update status */
- nop
-
- /*
- * STACK
- */
- pfx %hi(CONFIG_SYS_INIT_SP)
- movi %sp, %lo(CONFIG_SYS_INIT_SP)
- pfx %xhi(CONFIG_SYS_INIT_SP)
- movhi %sp, %xlo(CONFIG_SYS_INIT_SP)
- mov %fp, %sp
-
- pfx %hi(4*16)
- subi %sp, %lo(4*16) /* Space for reg window mgmt */
-
- /*
- * RELOCATE -- %g7 has return addr from bsr at _start.
- */
- pfx %hi(__u_boot_cmd_end)
- movi %g5, %lo(__u_boot_cmd_end)
- pfx %xhi(__u_boot_cmd_end)
- movhi %g5, %xlo(__u_boot_cmd_end) /* %g5 <- end address */
-
- lsli %g7, 1 /* mem = retaddr << 1 */
- mov %g6, %g7
- subi %g6, 4 /* %g6 <- src addr */
- ld %g7, [%g7] /* %g7 <- dst addr */
-
- /* No need to move text sections if we're already located
- * at the proper address.
- */
- cmp %g7, %g6
- ifs cc_z
- br reloc
- nop /* delay slot */
-
-1: cmp %g7, %g5
- skps cc_nz
- br 2f
- nop /* delay slot */
-
- ld %g0, [%g6]
- addi %g6, 4 /* src++ */
- st [%g7], %g0
- addi %g7, 4 /* dst++ */
- br 1b
- nop /* delay slot */
-2:
-
- /*
- * Jump to relocation address
- */
- pfx %hi(reloc@h)
- movi %g0, %lo(reloc@h)
- pfx %xhi(reloc@h)
- movhi %g0, %xlo(reloc@h)
- jmp %g0
- nop /* delay slot */
-reloc:
-
- /*
- * CLEAR BSS
- */
- pfx %hi(__bss_end)
- movi %g5, %lo(__bss_end)
- pfx %xhi(__bss_end)
- movhi %g5, %xlo(__bss_end) /* %g5 <- end address */
- pfx %hi(__bss_start)
- movi %g7, %lo(__bss_start)
- pfx %xhi(__bss_start)
- movhi %g7, %xlo(__bss_start) /* %g7 <- end address */
-
- movi %g0, 0
-3: cmp %g7, %g5
- skps cc_nz
- br 4f
- nop /* delay slot */
-
- st [%g7], %g0
- addi %g7, 4 /* (delay slot) dst++ */
- br 3b
- nop /* delay slot */
-4:
-
- /*
- * INIT VECTOR TABLE
- */
- pfx %hi(CONFIG_SYS_VECT_BASE)
- movi %g0, %lo(CONFIG_SYS_VECT_BASE)
- pfx %xhi(CONFIG_SYS_VECT_BASE)
- movhi %g0, %xlo(CONFIG_SYS_VECT_BASE) /* dst */
- mov %l0, %g0
-
- pfx %hi(_vectors)
- movi %g1, %lo(_vectors)
- pfx %xhi(_vectors)
- movhi %g1, %xlo(_vectors) /* src */
- bgen %g2, 6 /* cnt = 64 */
-
- ldp %g3, [%l0, 3] /* bkpt vector */
- ldp %g4, [%l0, 4] /* single step vector */
-
-5: ld %g7, [%g1]
- addi %g1, 4 /* src++ */
- st [%g0], %g7
- addi %g0, 4 /* dst++ */
-
- subi %g2, 1 /* cnt-- */
- ifrnz %g2
- br 5b
- nop /* delay slot */
-
-#if defined(CONFIG_ROM_STUBS)
- /* Restore the breakpoint and single step exception
- * vectors to their original values.
- */
- stp [%l0,3], %g3 /* breakpoint */
- stp [%l0,4], %g4 /* single step */
-#endif
-
- /* For debug startup convenience ... software breakpoints
- * set prior to this point may not succeed ;-)
- */
- .global __start
-__start:
-
- /*
- * Call board_init -- never returns
- */
- pfx %hi(board_init@h)
- movi %g1, %lo(board_init@h)
- pfx %xhi(board_init@h)
- movhi %g1, %xlo(board_init@h)
- call %g1
- nop /* Delaly slot */
- /* NEVER RETURNS */
-
-/*
- * dly_clks -- Nios doesn't have a time/clk reference for simple
- * delay loops, so we do our best by counting instruction cycles.
- * A control register that counts system clock cycles would be
- * a handy feature -- hint for Altera ;-)
- */
- .globl dly_clks
- /* Each loop is 4 instructions as delay slot is always
- * executed. Each instruction is approximately 4 clocks
- * (according to some lame info from Altera). So ...
- * ... each loop is about 16 clocks.
- */
-
-dly_clks:
- lsri %o0, 4 /* cnt/16 */
-
-8: skprnz %o0
- br 9f
- subi %o0, 1 /* cnt--, Delay slot */
- br 8b
- nop
-
-9: lret
- nop /* Delay slot */
-
-
- .data
- .globl version_string
-
-version_string:
- .ascii U_BOOT_VERSION
- .ascii " (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
- .ascii CONFIG_IDENT_STRING, "\0"
projects / u-boot / blobdiff