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Perform more optimization in supercard platform (#107)

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This commit is contained in:
Edoardo Lolletti
2026-01-12 21:23:02 +01:00
committed by GitHub
parent 08cf835b05
commit 61ab97091a
6 changed files with 174 additions and 111 deletions
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12
arm9/source/patches/platform/supercard/SuperCardCommon.h
View File

@@ -6,8 +6,8 @@ DEFINE_SECTION_SYMBOLS(scsd_change_mode);
DEFINE_SECTION_SYMBOLS(scsd_common);
extern "C" void sccmn_changeMode();
extern "C" void sccmn_sdSendClock10();
extern "C" void sccmn_sdio4BitCrc16();
class SuperCardChangeModePatchCode : public PatchCode
@@ -20,6 +20,11 @@ public:
{
return GetAddressAtTarget((void*)sccmn_changeMode);
}
const void* GetSdSendClock10Function() const
{
return GetAddressAtTarget((void*)sccmn_sdSendClock10);
}
};
class SuperCardCommonPatchCode : public PatchCode
@@ -28,11 +33,6 @@ public:
explicit SuperCardCommonPatchCode(PatchHeap& patchHeap)
: PatchCode(SECTION_START(scsd_common), SECTION_SIZE(scsd_common), patchHeap) { }
const void* GetSdSendClock10Function() const
{
return GetAddressAtTarget((void*)sccmn_sdSendClock10);
}
const void* GetCrc16ChecksumFunction() const
{
return GetAddressAtTarget((void*)sccmn_sdio4BitCrc16);

21
arm9/source/patches/platform/supercard/SuperCardCommon.s
View File

@@ -8,6 +8,7 @@
@ void sc_change_mode(uint16_t mode);
BEGIN_THUMB_FUNCTION sccmn_changeMode
push {r0-r3,lr}
ldr r2,= 0x09FFFFFE
ldr r3,= 0xA55A
strh r3, [r2]
@@ -19,24 +20,26 @@ BEGIN_THUMB_FUNCTION sccmn_changeMode
@ if mode is 3 (sd enable), reset the sd card
@ SDResetCard
@ write 0
ldr r2,= sd_resetaddr
ldr r2, =sd_resetaddr
strh r2, [r2]
1:
mov pc, lr
pop {r0-r3,pc}
.section "scsd_common", "ax"
@ this function will trash r4 but leave r0 and r1 untouched
@ void SDSendClock10(void)
BEGIN_THUMB_FUNCTION sccmn_sdSendClock10
@ here we get lr from the caller
push {r0-r3}
movs r3, #0x10
@ loads reg_scsd_cmd
movs r2, #0x98
lsls r2, r2, #20
1:
ldrh r4, [r2]
ldrh r0, [r2]
subs r3, r3, #1
bne 1b
mov pc, lr
pop {r0-r3,pc}
.section "scsd_common", "ax"
@ static uint64_t inline calSingleCRC16(uint64_t crc, uint32_t data_in){
@ // Shift out 8 bits for each line
@@ -73,8 +76,10 @@ BEGIN_THUMB_FUNCTION sccmn_sdSendClock10
@ uint64_t sdio_crc16_4bit_checksum(void*)
@ r0 and r1 are left untouched, the result is returned in r2-r3 instead
@ a "continuation function" is provided in r5, and we have to jump to it
BEGIN_THUMB_FUNCTION sccmn_sdio4BitCrc16
push {r0,r1,r4-r5,lr}
push {r5,lr}
push {r0,r1,r4-r5}
movs r4, #0 @ r4 = crc_lo
movs r5, #0 @ r5 = crc_hi
movs r1, #128
@@ -116,7 +121,7 @@ byteSwap32:
push {r0,r1,r4-r5,lr}
byteSwap32_nopush:
movs r5, #16
ldr r4,= 0xFF00FF
ldr r4, =0xFF00FF
rors r2, r5 // ror 16
ands r4, r2
bics r2, r4

4
arm9/source/patches/platform/supercard/sclite/SuperCardLiteImpl.h
View File

@@ -83,7 +83,7 @@ public:
INTERWORK_LABEL(sclite_sdCommandAndDropResponse6, readInterwork)
= (u32)superCardSdCommandAndDropLitePatchCode->GetSdCommandAndDropResponse6Function();
INTERWORK_LABEL(sclite_readData, readInterwork) = (u32)superCardReadDataLitePatchCode->GetReadDataLiteFunction();
INTERWORK_LABEL(sccmn_sdSendClock10, readInterwork) = (u32)superCardCommonPatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_sdSendClock10, readInterwork) = (u32)superCardChangeModePatchCode->GetSdSendClock10Function();
}
const ReadSectorsFunc GetReadSectorsFunction() const override
@@ -104,7 +104,7 @@ public:
{
INTERWORK_LABEL(sclite_writeData, writeInterwork) = (u32)superCardWriteDataLitePatchCode->GetWriteDataLiteFunction();
INTERWORK_LABEL(sccmn_sdio4BitCrc16, writeInterwork) = (u32)superCardCommonPatchCode->GetCrc16ChecksumFunction();
INTERWORK_LABEL(sccmn_sdSendClock10, writeInterwork) = (u32)superCardCommonPatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_sdSendClock10, writeInterwork) = (u32)superCardChangeModePatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_changeMode, writeInterwork) = (u32)superCardChangeModePatchCode->GetScChangeModeFunction();
INTERWORK_LABEL(sclite_sdCommandAndDropResponse6, writeInterwork)
= (u32)superCardSdCommandAndDropLitePatchCode->GetSdCommandAndDropResponse6Function();

127
arm9/source/patches/platform/supercard/sclite/SuperCardLiteImpl.s
View File

@@ -40,12 +40,19 @@
.section "sclite_sd_command_drop", "ax"
@ void sclite_sdCommandAndDropResponse6(uint32_t dummy, uint32_t argument, SD_COMMANDS command)
@ command is passed in r2
@ command is passed in r2, in r6 is the pointer to sccmn_sdSendClock10
BEGIN_THUMB_FUNCTION sclite_sdCommandAndDropResponse6
push {lr}
cmp r2, #0x52
@ if command is READ_MULTIPLE_BLOCK, don't send extra clock cycles
beq 1f
@ we need to call sccmn_sdSendClock10 after the command is sent, push sccmn_sdSendClock10 and the lr to the stack
push {r6}
1:
@ among the pushed registers there are the command and
@ argument one, which are then used at the loop to
@ send the sd command
push {r1-r7,lr}
push {r1-r7}
@ loads reg_scsd_cmd
movs r7, #0x98
@@ -100,8 +107,11 @@ SDCommand_drop_resp:
subs r6, r6, #1
bne SDCommand_drop_resp
@ restore stack space
@ we pop from the stack r6 as pc, which corresponds to sccmn_sdSendClock10 or lr, if it is sccmn_sdSendClock10 that function
@ is called, and that function doesn't push a new lr but pops a preexisting one from the stack, which in our case is the
@ lr provided to this function
pop {r1-r7,pc}
.balign 4
.pool
@@ -110,7 +120,7 @@ SDCommand_drop_resp:
BEGIN_THUMB_FUNCTION sclite_writeSector
push {r1,r2,r4-r7,lr}
@ load EXMEMCNT register
@ load EXMEMCNT register into r7
LOAD_EXMEMCNT
@ r1 for now holds the sector
@@ -120,80 +130,96 @@ sclite_writeSectorSdhcLabel:
lsls r1, r0, #9
@ movs r1, r0
@ r4 sccmn_changeMode
@ r5 sclite_sdCommandAndDropResponse6
@ r6 sccmn_sdSendClock10
adr r3, sccmn_changeMode_writeInterworkLite_address
ldmia r3!, {r4-r6}
@ enable sd access
@ this function won't touch r1
@ this function won't touch anything
movs r0, #3
CALL sccmn_changeMode writeInterwork
@ call sccmn_changeMode
bl interwork_r4
@ WRITE_MULTIPLE_BLOCK
@ puts the value in r2
SD_COMMAND_ARGUMENT #25
@ 2nd parameter is in r1 from above
CALL sclite_sdCommandAndDropResponse6 writeInterwork
@ call sclite_sdCommandAndDropResponse6
bl interwork_r5
@ this function will trash r4 but leave r0 and r1 untouched
CALL sccmn_sdSendClock10 writeInterwork
@ load the rest of the functions
@ r4 sccmn_sdio4BitCrc16
@ r5 sclite_writeData
ldmia r3!, {r4-r5}
@ loads the saved r0 and r2 (readnum)
@ loads the saved r1 (buff) and r2 (writenum)
@ into r0 and r1
pop {r0,r1}
write_sector_loop:
@ all the functions called in this loop don't change the value of r0 and r1
@ all the functions called in this loop don't change the value of any register
@ except sclite_writeData, which will increase r0 by 512
@ sccmn_sdio4BitCrc16 will write the checksum to r2-r3
CALL sccmn_sdio4BitCrc16 writeInterwork
@ first argument is buffer
@ regs r2 and r3 hold the crc
CALL sclite_writeData writeInterwork
@ this function will trash r4 but leave r0 and r1 untouched
CALL sccmn_sdSendClock10 writeInterwork
@ call sccmn_sdio4BitCrc16, this function will then tail call to r5 (sclite_writeData)
bl interwork_r4
subs r1, #1
bne write_sector_loop
adr r3, sccmn_changeMode_writeInterworkLite_address
@ r4 sccmn_changeMode
@ r5 sclite_sdCommandAndDropResponse6
ldmia r3!, {r4-r5}
@ STOP_TRANSMISSION
@ puts the value in r2
SD_COMMAND_ARGUMENT #12
@ 2nd parameter is passed in r1
@ and from the loop above r1 is already 0
CALL sclite_sdCommandAndDropResponse6 writeInterwork
@ this function will trash r4 but leave r0 and r1 untouched
CALL sccmn_sdSendClock10 writeInterwork
@ call sclite_sdCommandAndDropResponse6
bl interwork_r5
@ loads sd_dataadd
movs r0, #0x90
lsls r0, r0, #20
@ while(*r1 &0x100) == 0
@ while(*r0 &0x100) == 0
beginwhile_WriteSector:
ldrh r1, [r0]
lsrs r1, #9
bcc beginwhile_WriteSector
movs r0, #1
CALL sccmn_changeMode writeInterwork
@ call sccmn_changeMode writeInterwork
bl interwork_r4
@ restore EXMEMCNT register
RESTORE_EXMEMCNT
pop {r4-r7,pc}
INTERWORK writeInterwork
INTERWORK_FUNCTION sclite_writeData writeInterwork
INTERWORK_FUNCTION sccmn_sdio4BitCrc16 writeInterwork
INTERWORK_FUNCTION sccmn_sdSendClock10 writeInterwork
INTERWORK_FUNCTION sccmn_changeMode writeInterwork
INTERWORK_FUNCTION sclite_sdCommandAndDropResponse6 writeInterwork
interwork_r4:
bx r4
interwork_r5:
bx r5
.balign 4
.pool
INTERWORK_FUNCTION sccmn_changeMode writeInterwork
INTERWORK_FUNCTION sclite_sdCommandAndDropResponse6 writeInterwork
INTERWORK_FUNCTION sccmn_sdSendClock10 writeInterwork
INTERWORK_FUNCTION sccmn_sdio4BitCrc16 writeInterwork
INTERWORK_FUNCTION sclite_writeData writeInterwork
.section "sclite_read_sector", "ax"
@ bool sclite_readSector(uint32_t sector, uint8_t *buff, uint32_t readnum)
BEGIN_THUMB_FUNCTION sclite_readSector
push {r1,r2-r7,lr}
@ load EXMEMCNT register into r7
LOAD_EXMEMCNT
@ r1 for now holds the sector
@@ -204,21 +230,22 @@ sclite_readSectorSdhcLabel:
@ movs r1, r0
@ enable sd access
@ this function won't touch r1
@ this function won't touch anything
movs r0, #3
CALL sccmn_changeMode readInterwork
@ READ_MULTIPLE_BLOCK
@ puts the value in r2
SD_COMMAND_ARGUMENT #18
@ 2nd parameter is in r1 from above
CALL sclite_sdCommandAndDropResponse6 readInterwork
@ loads the saved r0 and r2 (writenum)
@ loads the saved r1 (buff) and r2 (readnum)
@ into r0 and r1
pop {r0,r1}
read_sector_loop:
@ all the functions called in this loop don't change the value of r0 or r1
@ all the functions called in this loop don't change the value of any register
@ except sclite_readData, which will increase r0 by 512 automatically
CALL sclite_readData readInterwork
@@ -226,14 +253,15 @@ read_sector_loop:
bne read_sector_loop
@ STOP_TRANSMISSION
@ puts the value in r2
SD_COMMAND_ARGUMENT #12
@ 2nd parameter is passed in r1
@ and from the loop above r1 is already 0
LOAD_INTERWORK_FUNCTION sccmn_sdSendClock10 readInterwork r6
CALL sclite_sdCommandAndDropResponse6 readInterwork
@ this function will trash r4 but leave r0 and r1 untouched
CALL sccmn_sdSendClock10 readInterwork
@ this function won't touch anything
@ CALL sccmn_sdSendClock10 readInterwork
movs r0, #1
@@ -312,15 +340,17 @@ sclite_readData_loop:
.section "sclite_write_data", "ax"
@ void sclite_writeData(void*& buffer, int value_to_keep, int crc_buff1, int crc_buff2)
@ this function updates r0, leaves r1 untouched and thrashes r4
@ this function updates r0 and leaves everything else untouched
@ in r6 is the pointer to sccmn_sdSendClock10
BEGIN_THUMB_FUNCTION sclite_writeData
@ push sccmn_sdSendClock10 and the current lr reg to the stack, so that at the end we can
@ call in sequence sccmn_sdSendClock10 and then return
push {r6}
push {r1-r7}
@ loads sd_dataadd
movs r4, #0x90
lsls r4, r4, #20
@ save sd_dataadd constant above for later
push {r1-r7,lr}
waitOnWriteFalse_WriteData:
ldrh r1, [r4]
lsrs r1, #9
@@ -356,9 +386,12 @@ sclite_writeData_loop:
@ r1 holds a value that has not to be changed
@ r2-r3 hold the crc value to be written
@ r4 holds the value sd_dataadd saved at the start
pop {r1-r4}
pop {r1-r3}
stmia r7!, {r2-r3}
@ loads sd_dataadd
movs r4, #0x90
lsls r4, r4, #20
@ write end bit
movs r3, #0xff
@@ -374,7 +407,11 @@ waitOnWriteTrue_WriteData:
str r3, [r4]
str r3, [r4]
pop {r5-r7,pc}
@ we pop from the stack r6 as pc, which corresponds to sccmn_sdSendClock10 so we jump to it
@ sccmn_sdSendClock10 doesn't push a new lr but pops a preexisting one from the stack, which in our case is the
@ lr provided to this function
pop {r4-r7,pc}
.balign 4
.pool

4
arm9/source/patches/platform/supercard/scsd/SuperCardSDImpl.h
View File

@@ -81,7 +81,7 @@ public:
{
INTERWORK_LABEL(scsd_writeData, writeInterwork) = (u32)superCardWriteDataPatchCode->GetWriteDataFunction();
INTERWORK_LABEL(sccmn_sdio4BitCrc16, writeInterwork) = (u32)superCardCommonPatchCode->GetCrc16ChecksumFunction();
INTERWORK_LABEL(sccmn_sdSendClock10, writeInterwork) = (u32)superCardCommonPatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_sdSendClock10, writeInterwork) = (u32)superCardChangeModePatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_changeMode, writeInterwork) = (u32)superCardChangeModePatchCode->GetScChangeModeFunction();
INTERWORK_LABEL(scsd_sdCommandAndDropResponse6, writeInterwork)
= (u32)superCardSdCommandAndDropPatchCode->GetSdCommandAndDropResponse6Function();
@@ -107,7 +107,7 @@ public:
INTERWORK_LABEL(scsd_sdCommandAndDropResponse6, readInterwork)
= (u32)superCardSdCommandAndDropPatchCode->GetSdCommandAndDropResponse6Function();
INTERWORK_LABEL(scsd_readData, readInterwork) = (u32)superCardReadDataPatchCode->GetReadDataFunction();
INTERWORK_LABEL(sccmn_sdSendClock10, readInterwork) = (u32)superCardCommonPatchCode->GetSdSendClock10Function();
INTERWORK_LABEL(sccmn_sdSendClock10, readInterwork) = (u32)superCardChangeModePatchCode->GetSdSendClock10Function();
}
const ReadSectorsFunc GetReadSectorsFunction() const override

117
arm9/source/patches/platform/supercard/scsd/SuperCardSDImpl.s
View File

@@ -23,9 +23,9 @@
.macro LOAD_FAST_EXMEMCNT
@ loads EXMEMCNT register address
movs r6, #0x18
movs r0, #0x18
@ waitstate 2,1 and arm9 slot2 access
strb r6, [r7, #4]
strb r0, [r7, #4]
.endm
.macro RESTORE_EXMEMCNT
@@ -43,11 +43,18 @@
@ void scsd_sdCommandAndDropResponse6(uint32_t dummy, uint32_t argument, SD_COMMANDS command)
@ argument is passed in r1
BEGIN_THUMB_FUNCTION scsd_sdCommandAndDropResponse6
push {lr}
cmp r2, #0x52
@ if command is READ_MULTIPLE_BLOCK, don't send extra clock cycles
beq 1f
@ we need to call sccmn_sdSendClock10 after the command is sent, push sccmn_sdSendClock10 and the lr to the stack
push {r6}
1:
@ among the pushed registers there are the command and
@ argument one, which are then used by the crc7 function
@ and in the loop at the bottom
@ also allocate an extra 4 bytes for the SD_CRC7 function to put the crc byte
push {r0-r7,lr}
push {r0-r7}
@ pass the buffer incremented by 4, so that the crc function
@ can use a proper indexing method
@@ -99,7 +106,9 @@ SDCommand_drop_resp:
subs r6, r6, #1
bne SDCommand_drop_resp
@ restore stack space
@ we pop from the stack r6 as pc, which corresponds to sccmn_sdSendClock10 or lr, if it is sccmn_sdSendClock10 that function
@ is called, and that function doesn't push a new lr but pops a preexisting one from the stack, which in our case is the
@ lr provided to this function
pop {r0-r7,pc}
@ inline uint8_t CRC7_one(uint8_t crcIn, uint8_t data) {
@@ -169,7 +178,7 @@ skip_xor:
BEGIN_THUMB_FUNCTION scsd_writeSector
push {r1,r2,r4-r7,lr}
@ load EXMEMCNT register
@ load EXMEMCNT register into r7
LOAD_SLOW_EXMEMCNT
@ r1 for now holds the sector
@@ -179,23 +188,34 @@ scsd_writeSectorSdhcLabel:
lsls r1, r0, #9
@ movs r1, r0
@ r4 sccmn_changeMode
@ r5 scsd_sdCommandAndDropResponse6
@ r6 sccmn_sdSendClock10
adr r3, sccmn_changeMode_writeInterwork_address
ldmia r3!, {r4-r6}
@ enable sd access
@ this function won't touch r1
@ this function won't touch anything
movs r0, #3
bl scsd_sccmn_changeMode_call
@ call sccmn_changeMode
bl interwork_r4
@ WRITE_MULTIPLE_BLOCK
SD_COMMAND_ARGUMENT #25
@ 2nd parameter is in r1 from above
bl scsd_sdCommandAndDropResponse6_call
@ this function will trash r4 but leave r0 and r1 untouched
bl scsd_sccmn_sdSendClock10_call
@ call scsd_sdCommandAndDropResponse6
bl interwork_r5
LOAD_FAST_EXMEMCNT
@ loads the saved r0 and r2 (readnum)
@ load the rest of the functions
@ r4 sccmn_sdio4BitCrc16
@ r5 scsd_writeData
ldmia r3!, {r4-r5}
@ loads the saved r1 (buff) and r2 (writenum)
@ into r0 and r1
pop {r0,r1}
@@ -203,18 +223,17 @@ write_sector_loop:
@ all the functions called in this loop don't change the value of r0 and r1
@ except scsd_writeData, which will increase r0 by 512
@ sccmn_sdio4BitCrc16 will write the checksum to r2-r3
CALL sccmn_sdio4BitCrc16 writeInterwork
@ first argument is buffer
@ regs r2 and r3 hold the crc
CALL scsd_writeData writeInterwork
@ this function will trash r4 but leave r0 and r1 untouched
bl scsd_sccmn_sdSendClock10_call
@ call sccmn_sdio4BitCrc16, this function will then tail call to r5 (scsd_writeData)
bl interwork_r4
subs r1, #1
bne write_sector_loop
adr r3, sccmn_changeMode_writeInterwork_address
@ r4 sccmn_changeMode
@ r5 scsd_sdCommandAndDropResponse6
ldmia r3!, {r4-r5}
RELOAD_SLOW_EXMEMCNT
@ STOP_TRANSMISSION
@@ -222,39 +241,38 @@ write_sector_loop:
@ 2nd parameter is passed in r1
@ and from the loop above r1 is already 0
bl scsd_sdCommandAndDropResponse6_call
@ call scsd_sdCommandAndDropResponse6
bl interwork_r5
@ this function will trash r4 but leave r0 and r1 untouched
bl scsd_sccmn_sdSendClock10_call
@ loads sd_dataadd
movs r0, #0x90
lsls r0, r0, #20
@ SD_DATAADD is loaded by scsd_writeData into r5
@ while(*r5 &0x100) == 0
@ while(*r0 &0x100) == 0
beginwhile_WriteSector:
ldrh r1, [r5]
ldrh r1, [r0]
lsrs r1, #9
bcc beginwhile_WriteSector
movs r0, #1
bl scsd_sccmn_changeMode_call
@ call sccmn_changeMode writeInterwork
bl interwork_r4
@ restore EXMEMCNT register
RESTORE_EXMEMCNT
pop {r4-r7,pc}
scsd_sccmn_sdSendClock10_call:
LOAD_INTERWORK_FUNCTION sccmn_sdSendClock10 writeInterwork r4
interwork_r4:
bx r4
scsd_sdCommandAndDropResponse6_call:
LOAD_INTERWORK_FUNCTION scsd_sdCommandAndDropResponse6 writeInterwork r4
bx r4
scsd_sccmn_changeMode_call:
LOAD_INTERWORK_FUNCTION sccmn_changeMode writeInterwork r4
INTERWORK writeInterwork
INTERWORK_FUNCTION scsd_writeData writeInterwork
INTERWORK_FUNCTION sccmn_sdio4BitCrc16 writeInterwork
INTERWORK_FUNCTION sccmn_sdSendClock10 writeInterwork
interwork_r5:
bx r5
.balign 4
.pool
INTERWORK_FUNCTION sccmn_changeMode writeInterwork
INTERWORK_FUNCTION scsd_sdCommandAndDropResponse6 writeInterwork
INTERWORK_FUNCTION sccmn_sdSendClock10 writeInterwork
INTERWORK_FUNCTION sccmn_sdio4BitCrc16 writeInterwork
INTERWORK_FUNCTION scsd_writeData writeInterwork
.section "scsd_read_sector", "ax"
@@ -283,7 +301,7 @@ scsd_readSectorSdhcLabel:
LOAD_FAST_EXMEMCNT
@ loads the saved r0 and r2 (writenum)
@ loads the saved r1 (buff) and r2 (readnum)
@ into r0 and r1
pop {r0,r1}
read_sector_loop:
@@ -300,13 +318,9 @@ read_sector_loop:
SD_COMMAND_ARGUMENT #12
@ 2nd parameter is passed in r1
@ and from the loop above r1 is already 0
LOAD_INTERWORK_FUNCTION sccmn_sdSendClock10 readInterwork r6
CALL scsd_sdCommandAndDropResponse6 readInterwork
@ this function will trash r4 but leave r0 and r1 untouched
CALL sccmn_sdSendClock10 readInterwork
movs r0, #1
CALL sccmn_changeMode readInterwork
@@ -357,14 +371,15 @@ write32_loop:
@ void scsd_writeData(void* buffer, int value_to_keep, int crc_buff1, int crc_buff2)
BEGIN_THUMB_FUNCTION scsd_writeData
@ push sccmn_sdSendClock10 and the current lr reg to the stack, so that at the end we can
@ call in sequence sccmn_sdSendClock10 and then return
push {r6}
push {r1-r7}
@ loads SD_DATAADD, do it before the push so that
@ it becomes available to the callee afterwards
@ loads SD_DATAADD
movs r5, #0x90
lsls r5, r5, #20
push {r1-r7,lr}
@ while(*r5 &0x100) == 0
scsd_writeData_waitOnWriteFalse:
ldrh r6, [r5]
@@ -384,6 +399,7 @@ scsd_writeData_waitOnWriteFalse:
lsls r1, r1, #2
@ no need for special handling because those 2 functions will be in the same block
bl SCSD_writeBuffer32
@ save incremented r0 register
push {r0}
movs r1, #8
@@ -403,6 +419,11 @@ scsd_writeData_waitOnWriteTrue:
lsrs r6, #9
bcs scsd_writeData_waitOnWriteTrue
@ we pop from the stack r6 as pc, which corresponds to sccmn_sdSendClock10 so we jump to it
@ sccmn_sdSendClock10 doesn't push a new lr but pops a preexisting one from the stack, which in our case is the
@ lr provided to this function
@ also we load in r0 the value stored above
pop {r0-r7,pc}
.balign 4