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.set noreorder
.include "hwregs_a.h"
.section .text
.global CdGetSector
.type CdGetSector, @function
CdGetSector:
lui $a2, IOBASE
#.Lwait_fifo: # Probably redundant as the BIOS CD-ROM
# lbu $v0, CD_REG0($a2) # routines do not not wait for this
# nop
# andi $v0, 0x40
# beqz $v0, .Lwait_fifo
# nop
lui $v0, 0x1
# srl $a1, 2 # (the official implementation expects $a1/size
# to be in 32-bit words rather than bytes)
or $v0, $a1
sw $a0, DMA3_MADR($a2) # Set DMA base address and transfer length
sw $v0, DMA3_BCR($a2)
lui $v0, 0x1100 # Start DMA transfer
sw $v0, DMA3_CHCR($a2)
nop
nop
.Ldma_wait: # Ensure DMA transfer has completed
lw $v0, DMA3_CHCR($a2)
nop
srl $v0, 24
andi $v0, 0x1
bnez $v0, .Ldma_wait
nop
# Not stable
# sb $0 , CD_REG0($a2)
#.Lflush_fifo: # Read out any remaining bytes in the buffer
# lbu $v1, CD_REG0($a2)
# li $v0, 0x40
# and $v1, $v0
# beqz $v1, .Lend_flush
# nop
# lbu $v0, CD_REG2($a2)
# b .Lflush_fifo
# nop
#.Lend_flush:
jr $ra
li $v0, 1
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