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Line 36... |
.section .text.boot
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.section .text.boot
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.balign 4
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.balign 4
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.global _start
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.global _start
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// IO region
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.equ IO_BEGIN, 0xFFFFFF00 // start of processor-internal IO region
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_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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| Line 56... |
Line 52... |
addi x3, x0, 0
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addi x3, x0, 0
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addi x4, x0, 0
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addi x4, x0, 0
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addi x5, x0, 0
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addi x5, x0, 0
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addi x6, x0, 0
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addi x6, x0, 0
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addi x7, x0, 0
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addi x7, x0, 0
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addi x8, x0, 0
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//addi x8, x0, 0
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addi x9, x0, 0
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//addi x9, x0, 0
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//addi x10, x0, 0
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//addi x10, x0, 0
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//addi x11, x0, 0
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//addi x11, x0, 0
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//addi x12, x0, 0
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//addi x12, x0, 0
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//addi x13, x0, 0
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//addi x13, x0, 0
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addi x14, x0, 0
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addi x14, x0, 0
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| Line 102... |
Line 98... |
// no access from less-privileged modes to counter CSRs
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// no access from less-privileged modes to counter CSRs
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csrw mcounteren, zero
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csrw mcounteren, zero
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// stop all counters except for [m]cycle[h] and [m]instret[h]
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// stop all counters except for [m]cycle[h] and [m]instret[h]
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li x11, ~5
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li x11, ~5
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csrw mcountinhibit, x11
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csrw 0x320, x11 // mcountinhibit (literal address for lagacy toolchain compatibility)
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// clear cycle counters
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// clear cycle counters
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csrw mcycle, zero
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csrw mcycle, zero
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csrw mcycleh, zero
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csrw mcycleh, zero
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Line 146... |
// 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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li x11, IO_BEGIN // start of processor-internal IO region
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la x8, __ctr0_io_space_begin // start of processor-internal IO region
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la x9, __ctr0_io_space_end // end of processor-internal IO region
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__crt0_reset_io_loop:
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__crt0_reset_io_loop:
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sw zero, 0(x11)
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sw zero, 0(x8)
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addi x11, x11, 4
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addi x8, x8, 4
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bne zero, x11, __crt0_reset_io_loop
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bne x8, x9, __crt0_reset_io_loop
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// *********************************************************
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// *********************************************************
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// Clear .bss section (byte-wise) using linker script symbols
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// Clear .bss section (byte-wise) using linker script symbols
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// *********************************************************
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// *********************************************************
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