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.section .text
start:
addi x1, zero, 0
addi x2, zero, 0
addi x3, zero, 0
addi x4, zero, 0
addi x5, zero, 0
addi x6, zero, 0
addi x7, zero, 0
addi x8, zero, 0
addi x9, zero, 0
addi x10, zero, 0
addi x11, zero, 0
addi x12, zero, 0
addi x13, zero, 0
addi x14, zero, 0
addi x15, zero, 0
addi x16, zero, 0
addi x17, zero, 0
addi x18, zero, 0
addi x19, zero, 0
addi x20, zero, 0
addi x21, zero, 0
addi x22, zero, 0
addi x23, zero, 0
addi x24, zero, 0
addi x25, zero, 0
addi x26, zero, 0
addi x27, zero, 0
addi x28, zero, 0
addi x29, zero, 0
addi x30, zero, 0
addi x31, zero, 0
li sp, 4*256
call main
loop:
j loop
.global flashio_worker_begin
.global flashio_worker_end
flashio_worker_begin:
# a0 ... data pointer
# a1 ... data length
# address of SPI ctrl reg
li t0, 0x02000000
# Set CS high, IO0 is output
li t1, 0x120
sh t1, 0(t0)
# Enable Manual SPI Ctrl
li t1, 0x00
sb t1, 3(t0)
# SPI transfer
flashio_worker_L1:
beqz a1, flashio_worker_L3
li t5, 8
lbu t2, 0(a0)
flashio_worker_L2:
srli t4, t2, 7
sb t4, 0(t0)
ori t4, t4, 0x10
sb t4, 0(t0)
lbu t4, 0(t0)
andi t4, t4, 2
srli t4, t4, 1
slli t2, t2, 1
or t2, t2, t4
andi t2, t2, 0xff
addi t5, t5, -1
bnez t5, flashio_worker_L2
sb t2, 0(a0)
addi a0, a0, 1
addi a1, a1, -1
j flashio_worker_L1
flashio_worker_L3:
# Back to MEMIO mode
li t1, 0x80
sb t1, 3(t0)
ret
flashio_worker_end:
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