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Diffstat (limited to 'arch/nios/cpu/start.S')
| -rw-r--r-- | arch/nios/cpu/start.S | 238 |
1 files changed, 0 insertions, 238 deletions
diff --git a/arch/nios/cpu/start.S b/arch/nios/cpu/start.S deleted file mode 100644 index 3578a04..0000000 --- a/arch/nios/cpu/start.S +++ /dev/null @@ -1,238 +0,0 @@ -/* - * (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" |