mirror of https://github.com/marqs85/ossc.git
88 lines
2.0 KiB
ArmAsm
88 lines
2.0 KiB
ArmAsm
// Copyright 2017 ETH Zurich and University of Bologna.
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// Copyright and related rights are licensed under the Solderpad Hardware
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// License, Version 0.51 (the “License”); you may not use this file except in
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// compliance with the License. You may obtain a copy of the License at
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// http://solderpad.org/licenses/SHL-0.51. Unless required by applicable law
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// or agreed to in writing, software, hardware and materials distributed under
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// this License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR
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// CONDITIONS OF ANY KIND, either express or implied. See the License for the
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// specific language governing permissions and limitations under the License.
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#include "pulpino.h"
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#define EXCEPTION_STACK_SIZE 72
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/* ========================================================= [ entry ] === */
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.section .text
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default_exc_handler:
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jal x0, default_exc_handler
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reset_handler:
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/* set all registers to zero */
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mv x1, x0
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mv x2, x1
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mv x3, x1
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mv x4, x1
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mv x5, x1
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mv x6, x1
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mv x7, x1
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mv x8, x1
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mv x9, x1
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mv x10, x1
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mv x11, x1
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mv x12, x1
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mv x13, x1
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mv x14, x1
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mv x15, x1
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/* stack initilization */
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la x2, _stack_start
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_start:
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.global _start
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/* clear BSS */
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la x14, _bss_start
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la x15, _bss_end
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bge x14, x15, zero_loop_end
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zero_loop:
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sw x0, 0(x14)
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addi x14, x14, 4
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ble x14, x15, zero_loop
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zero_loop_end:
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main_entry:
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/* jump to alt_main program entry point */
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jal alt_main
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/* =================================================== [ exceptions ] === */
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/* This section has to be down here, since we have to disable rvc for it */
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.section .vectors, "ax"
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.option norvc;
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// external interrupts are handled by the same callback
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// until compiler supports IRQ routines
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.org 0x00
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.rept 31
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nop
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.endr
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jal x0, default_exc_handler
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// reset vector
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.org 0x80
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jal x0, reset_handler
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// illegal instruction exception
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.org 0x84
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jal x0, default_exc_handler
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// ecall handler
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.org 0x88
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jal x0, default_exc_handler
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