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#include "encoding.h"
#define PGSHIFT 12
.global main
.section .text
main:
# Set up a page table entry that maps 0x0... to 0x8...
la t0, page_table
srli t0, t0, PGSHIFT
csrw CSR_SPTBR, t0
# update mstatus
csrr t1, CSR_MSTATUS
#if XLEN == 32
li t0, (MSTATUS_MPRV | (SPTBR_MODE_SV32 << 24))
#else
li t0, (MSTATUS_MPRV | (SPTBR_MODE_SV39 << 24))
#endif
#li t0, ((VM_SV39 << 24))
or t1, t0, t1
csrw CSR_MSTATUS, t1
la t0, (loop - 0x80000000)
csrw CSR_MEPC, t0
# Exit supervisor mode, entering user mode at loop.
mret
loop:
la t0, data
lw t1, 0(t0)
j loop
.section .data
data:
.word 0xbead
.balign 0x1000
page_table:
#if XLEN == 32
.word ((0x80000000 >> 2) | PTE_V | PTE_R | PTE_W | PTE_X | PTE_G | PTE_U)
#else
.word ((0x80000000 >> 2) | PTE_V | PTE_R | PTE_W | PTE_X | PTE_G | PTE_U)
.word 0
#endif
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