| Line 45... |
Line 45... |
_start:
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_start:
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.cfi_startproc
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.cfi_startproc
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.cfi_undefined ra
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.cfi_undefined ra
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// *********************************************************
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// *********************************************************
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// Clear register file (lower half, assume E extension)
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// Clear integer register file (lower half, assume E extension)
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// *********************************************************
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// *********************************************************
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__crt0_reg_file_clear:
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__crt0_reg_file_clear:
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//addi x0, x0, 0 // hardwired to zero
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//addi x0, x0, 0 // hardwired to zero
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addi x1, x0, 0
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addi x1, x0, 0
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addi x2, x0, 0
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addi x2, x0, 0
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| Line 67... |
Line 67... |
addi x14, x0, 0
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addi x14, x0, 0
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addi x15, x0, 0
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addi x15, x0, 0
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// *********************************************************
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// *********************************************************
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// Clear register file (upper half, if no E extension)
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// Initialize dummy trap handler base address
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// *********************************************************
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__crt0_neorv32_trap_init:
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la x11, __crt0_dummy_trap_handler
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csrw mtvec, x11 // set address of first-level exception handler
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// *********************************************************
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// Clear integer register file (upper half, if no E extension)
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// *********************************************************
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// *********************************************************
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#ifndef __riscv_32e
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#ifndef __riscv_32e
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// save some program space if compiling bootloader
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// DO NOT DO THIS if compiling bootloader (to save some program space)
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#ifndef make_bootloader
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#ifndef make_bootloader
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addi x16, x0, 0
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addi x16, x0, 0
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addi x17, x0, 0
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addi x17, x0, 0
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addi x18, x0, 0
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addi x18, x0, 0
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addi x19, x0, 0
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addi x19, x0, 0
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| Line 93... |
Line 101... |
#endif
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#endif
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#endif
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#endif
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// *********************************************************
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// *********************************************************
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// Clear floating-point register file (if F extension enabled)
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// *********************************************************
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#ifdef __riscv_flen
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// DO NOT DO THIS if compiling bootloader (to save some program space)
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#ifndef make_bootloader
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fmv.s.x f0, x0
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fmv.s.x f1, x0
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fmv.s.x f2, x0
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fmv.s.x f3, x0
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fmv.s.x f4, x0
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fmv.s.x f5, x0
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fmv.s.x f6, x0
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fmv.s.x f7, x0
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fmv.s.x f8, x0
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fmv.s.x f9, x0
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fmv.s.x f10, x0
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fmv.s.x f11, x0
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fmv.s.x f12, x0
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fmv.s.x f13, x0
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fmv.s.x f14, x0
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fmv.s.x f15, x0
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fmv.s.x f16, x0
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fmv.s.x f17, x0
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fmv.s.x f18, x0
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fmv.s.x f19, x0
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fmv.s.x f20, x0
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fmv.s.x f21, x0
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fmv.s.x f22, x0
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fmv.s.x f23, x0
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fmv.s.x f24, x0
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fmv.s.x f25, x0
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fmv.s.x f26, x0
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fmv.s.x f27, x0
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fmv.s.x f28, x0
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fmv.s.x f29, x0
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fmv.s.x f30, x0
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fmv.s.x f31, x0
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#endif
|
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#endif
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// *********************************************************
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// No interrupts, thanks
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// No interrupts, thanks
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// *********************************************************
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// *********************************************************
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__crt0_status_init:
|
__crt0_status_init:
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li x10, 0x00001800 // clear mstatus and set mpp(1:0)
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li x10, 0x00001800 // clear mstatus and set mpp(1:0)
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csrrw zero, mstatus, x10
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csrrw zero, mstatus, x10
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| Line 115... |
Line 165... |
la gp, __global_pointer$ // global pointer
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la gp, __global_pointer$ // global pointer
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.option pop
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.option pop
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// *********************************************************
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// *********************************************************
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// Initialize dummy trap handler base address
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// *********************************************************
|
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__crt0_neorv32_trap_init:
|
|
la x11, __crt0_dummy_trap_handler
|
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csrw mtvec, x11 // set address of first-level exception handler
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|
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// *********************************************************
|
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// Reset/deactivate IO/peripheral devices
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// Reset/deactivate IO/peripheral devices
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// Devices, that are not implemented, will cause a store access fault
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// Devices, that are not implemented, will cause a store access fault
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// which is captured but actually ignored due to the dummy handler.
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// which is captured but actually ignored due to the dummy handler.
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// *********************************************************
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// *********************************************************
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__crt0_reset_io:
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__crt0_reset_io:
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