mirror of
git://projects.qi-hardware.com/nn-usb-fpga.git
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86 lines
2.3 KiB
ArmAsm
86 lines
2.3 KiB
ArmAsm
/*
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* LatticeMico32 C startup code.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/* Exception handlers - Must be 32 bytes long. */
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.section .text, "ax", @progbits
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.global _start
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.global irq_enable, irq_disable, irq_mask, jump, halt
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_start:
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_reset_handler:
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xor r0, r0, r0
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wcsr IE, r0
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mvhi r1, hi(_reset_handler)
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ori r1, r1, lo(_reset_handler)
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wcsr EBA, r1
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calli _crt0
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nop
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nop
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_crt0:
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/* Setup stack and global pointer */
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mvhi sp, hi(_fstack)
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ori sp, sp, lo(_fstack)
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mvhi gp, hi(_gp)
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ori gp, gp, lo(_gp)
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/* Clear BSS */
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mvhi r1, hi(_fbss)
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ori r1, r1, lo(_fbss)
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mvhi r3, hi(_ebss)
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ori r3, r3, lo(_ebss)
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.clearBSS:
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be r1, r3, .callMain
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sw (r1+0), r0
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addi r1, r1, 4
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bi .clearBSS
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.callMain:
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mvi r1, 0
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mvi r2, 0
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mvi r3, 0
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calli main
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irq_enable:
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mvi r1, 1
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wcsr IE, r1
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ret
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irq_mask:
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mvi r1, 0x0000000f
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wcsr IM, r1
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ret
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irq_disable:
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mvi r1, 0
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wcsr IE, r1
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ret
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jump:
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b r1
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halt:
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bi halt
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