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author | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-08-09 20:57:11 +0000 |
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committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 2006-08-09 20:57:11 +0000 |
commit | 783669fcb3d0196034df104ca172bbb215a60237 (patch) | |
tree | bbfbed63163fe3657cfbce2a31df4a2816436d02 /c/src/lib/libbsp/nios2/nios2_iss/start/start.S | |
parent | * libnetworking/rtems/rtems_mii_ioctl_kern.c: (diff) | |
download | rtems-783669fcb3d0196034df104ca172bbb215a60237.tar.bz2 |
2006-08-09 Kolja Waschk <waschk@telos.de>
* ChangeLog, Makefile.am, README, acinclude.m4, configure.ac,
nios2_iss/ChangeLog, nios2_iss/Makefile.am, nios2_iss/bsp_specs,
nios2_iss/configure.ac, nios2_iss/nios2_iss.ptf,
nios2_iss/nios2_iss.sh, nios2_iss/times, nios2_iss/console/console.c,
nios2_iss/include/bsp.h, nios2_iss/include/bspopts.h.in,
nios2_iss/include/coverhd.h, nios2_iss/include/tm27.h,
nios2_iss/shmsupp/addrconv.c, nios2_iss/shmsupp/getcfg.c,
nios2_iss/shmsupp/lock.c, nios2_iss/shmsupp/mpisr.c,
nios2_iss/start/crtnn.s, nios2_iss/start/start.S,
nios2_iss/startup/bspclean.c, nios2_iss/startup/bspstart.c,
nios2_iss/startup/linkcmds, nios2_iss/startup/main.c,
nios2_iss/startup/setvec.c, nios2_iss/timer/timer.c: New files.
Diffstat (limited to 'c/src/lib/libbsp/nios2/nios2_iss/start/start.S')
-rw-r--r-- | c/src/lib/libbsp/nios2/nios2_iss/start/start.S | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/nios2/nios2_iss/start/start.S b/c/src/lib/libbsp/nios2/nios2_iss/start/start.S new file mode 100644 index 0000000000..532c12616e --- /dev/null +++ b/c/src/lib/libbsp/nios2/nios2_iss/start/start.S @@ -0,0 +1,124 @@ +/* NIOS2 startup code + * + * This is the entry point on reset and when loading the + * executive from a bootloader. + * + * COPYRIGHT (c) 2005-2006 Kolja Waschk rtemsdev/ixo.de + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.com/license/LICENSE. + * + * $Id$ + */ + + .section .entry + .align 3 + movhi et, %hiadj(start) + addi et, et, %lo(start) + jmp et + + .section .irq + .align 3 + movhi et, %hiadj(_exception_vector) + addi et, et, %lo(_exception_vector) + jmp et + + .section .text + .align 3 + .globl start + .type start,@function + + .extern _exception_vector + +start: + #------------------------------------------------------ + # disable interrupts + wrctl status, zero + wrctl ienable, zero + + #------------------------------------------------------ + # invalidate instruction cache + mov r2, r0 + movhi r3, %hi(__nios2_icache_size) + ori r3, r3, %lo(__nios2_icache_size) +icache_init_loop: + initi r2 + addi r2, r2, __nios2_icache_line_size + bltu r2, r3, icache_init_loop + + #------------------------------------------------------ + # invalidate data cache + mov r2, r0 + movhi r3, %hi(__nios2_dcache_size) + ori r3, r3, %lo(__nios2_dcache_size) +dcache_init_loop: + initd 0(r2) + addi r2, r2, __nios2_dcache_line_size + bltu r2, r3, dcache_init_loop + + #------------------------------------------------------ + # initialize stack pointer + movhi sp, %hiadj(__alt_stack_pointer - 4) + addi sp, sp, %lo(__alt_stack_pointer - 4) + + # initialize global pointer + movhi gp, %hiadj(_gp) + addi gp, gp, %lo(_gp) + + # initialize exception tmp register + movhi et, %hiadj(_end) + addi et, et, %lo(_end) + + #------------------------------------------------------ + # TODO: copy data from flash to RAM, if not there already + # For now its save to assume it is there already when we're + # loading code though JTAG into RAM-only system + + # at least copy exception code to right place + movhi r2, %hiadj(__ram_exceptions_start) + addi r2, r2, %lo(__ram_exceptions_start) + + movhi r3, %hiadj(brto_ev) + addi r3, r3, %lo(brto_ev) + ldw r4, 0(r3) + stw r4, 0(r2) + ldw r4, 4(r3) + stw r4, 4(r2) + ldw r4, 8(r3) + stw r4, 8(r2) + ldw r4, 12(r3) + stw r4, 12(r2) + + #------------------------------------------------------ + # clear bss + movhi r2, %hiadj(__bss_start) + addi r2, r2, %lo(__bss_start) + + movhi r3, %hiadj(__bss_end) + addi r3, r3, %lo(__bss_end) + + beq r2, r3, 1f +0: + stw zero, (r2) + addi r2, r2, 4 + bltu r2, r3, 0b +1: + #------------------------------------------------------ + # jump to (shared) boot_card (never comes back) + mov r4, zero + mov r5, zero + mov r6, zero + call boot_card + # but just in case it does come back, stick here. +_stuck_in_start: + br _stuck_in_start + + #------------------------------------------------------ + # code to be placed at exception address +brto_ev: + movhi et, %hiadj(_exception_vector) + addi et, et, %lo(_exception_vector) + jmp et + + |