diosmios/asm/CARDOpen.S

72 lines
1.1 KiB
ArmAsm

#include <asm.h>
#
# r3 chan
# r4 FileName
# r5 FileInfo
CARDOpen:
mflr %r0
stw %r0, 4(%sp)
stwu %sp, -0x10(%sp)
cmpwi %r3, 0
bne NoCard
#send cmd to DM
li %r0, 0
lis %r7, 0xC000
addi %r7, %r7, 0x2F60
#IPC area
dcbi %r0, %r7
addi %r7, %r7, 0x20
dcbi %r0, %r7
lis %r7, 0xC000
#cmd is the same as the offset, one opcode saved!
stw %r7, 0x2F60(%r7)
stw %r4, 0x2F64(%r7)
stw %r5, 0x2F68(%r7)
#cache workaround for the filename
li %r3, 8
mtctr %r3
lis %r3, 0xC000
invalidloop:
lwz %r0, 0(%r4)
stw %r0, 0x17E0(%r3)
addi %r4, %r4, 4
addi %r3, %r3, 4
bdnz invalidloop
li %r0, 3
stw %r0, 0x2F78(%r7)
ready_loop:
lwz %r0, 0x2F78(%r7)
cmpwi %r0, 3
beq ready_loop
wait_loop:
lwz %r0, 0x2F9C(%r7)
andi. %r0, %r0, 0x14
cmpwi %r0, 0
beq wait_loop
lwz %r0, 0x2F90(%r7)
stw %r0, 0x04(%r5)
lwz %r3, 0x2F94(%r7)
b end
NoCard:
li %r3, -3
end:
mr %r4, %r3
lwz %r0, 0x14(%sp)
addi %sp, %sp, 0x10
mtlr %r0
blr