gba-link-connection/lib/LinkCableMultiboot.hpp
2025-02-17 21:25:44 -03:00

1094 lines
36 KiB
C++

#ifndef LINK_CABLE_MULTIBOOT_H
#define LINK_CABLE_MULTIBOOT_H
// --------------------------------------------------------------------------
// A Multiboot tool to send small programs from one GBA to up to 3 slaves.
// --------------------------------------------------------------------------
// Usage:
// - 1) Include this header in your main.cpp file and add:
// LinkCableMultiboot* linkCableMultiboot = new LinkCableMultiboot();
// - 2) Send the ROM:
// LinkCableMultiboot::Result result = linkCableMultiboot->sendRom(
// romBytes, // for current ROM, use: ((const u8*)MEM_EWRAM)
// // ^ must be 4-byte aligned
// romLength, // in bytes, should be multiple of 16
// []() {
// u16 keys = ~REG_KEYS & KEY_ANY;
// return keys & KEY_START;
// // (when this returns true, the transfer will be canceled)
// }
// );
// // `result` should be LinkCableMultiboot::Result::SUCCESS
// - 3) (Optional) Send ROMs asynchronously:
// LinkCableMultiboot::Async* linkCableMultibootAsync =
// new LinkCableMultiboot::Async();
// interrupt_init();
// interrupt_add(INTR_VBLANK, LINK_CABLE_MULTIBOOT_ASYNC_ISR_VBLANK);
// interrupt_add(INTR_SERIAL, LINK_CABLE_MULTIBOOT_ASYNC_ISR_SERIAL);
// bool success = linkCableMultibootAsync->sendRom(romBytes, romLength);
// if (success) {
// // (monitor `playerCount()` and `getPercentage()`)
// if (!linkCableMultibootAsync->isSending()) {
// auto result = linkCableMultibootAsync->getResult();
// // `result` should be
// // LinkCableMultiboot::Async::GeneralResult::SUCCESS
// }
// }
// --------------------------------------------------------------------------
// considerations:
// - stop DMA before sending the ROM! (you might need to stop your audio player)
// - this restriction only applies to the sync version!
// --------------------------------------------------------------------------
#ifndef LINK_DEVELOPMENT
#pragma GCC system_header
#endif
#include "LinkRawCable.hpp"
#include "LinkSPI.hpp"
#ifndef LINK_CABLE_MULTIBOOT_PALETTE_DATA
/**
* @brief Palette data (controls how the logo is displayed).
* Format: 0b1CCCDSS1, where C=color, D=direction, S=speed.
* Default: 0b10010011
*/
#define LINK_CABLE_MULTIBOOT_PALETTE_DATA 0b10010011
#endif
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
/**
* @brief Disable nested IRQs (uncomment to enable).
* In the async version, SERIAL IRQs can be interrupted (once they clear their
* time-critical needs) by default, which helps prevent issues with audio
* engines. However, if something goes wrong, you can disable this behavior.
*/
// #define LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
#endif
LINK_VERSION_TAG LINK_CABLE_MULTIBOOT_VERSION = "vLinkCableMultiboot/v8.0.0";
#define LINK_CABLE_MULTIBOOT_TRY(CALL) \
partialResult = CALL; \
if (partialResult == PartialResult::ABORTED) \
return error(Result::CANCELED); \
else if (partialResult == PartialResult::NEEDS_RETRY) \
goto retry;
/**
* @brief A Multiboot tool to send small programs from one GBA to up to 3
* slaves.
*/
class LinkCableMultiboot {
private:
using u32 = Link::u32;
using u16 = Link::u16;
using u8 = Link::u8;
using vu32 = Link::vu32;
using vu8 = Link::vu8;
static constexpr int MIN_ROM_SIZE = 0x100 + 0xC0;
static constexpr int MAX_ROM_SIZE = 256 * 1024;
static constexpr int FRAME_LINES = 228;
static constexpr int INITIAL_WAIT_MIN_FRAMES = 4;
static constexpr int INITIAL_WAIT_MAX_RANDOM_FRAMES = 10;
static constexpr int INITIAL_WAIT_MIN_LINES =
FRAME_LINES * INITIAL_WAIT_MIN_FRAMES;
static constexpr int DETECTION_TRIES = 16;
static constexpr int MAX_CLIENTS = 3;
static constexpr int CLIENT_NO_DATA = 0xFF;
static constexpr int CMD_HANDSHAKE = 0x6200;
static constexpr int ACK_HANDSHAKE = 0x7200;
static constexpr int CMD_CONFIRM_CLIENTS = 0x6100;
static constexpr int CMD_SEND_PALETTE = 0x6300;
static constexpr int HANDSHAKE_DATA = 0x11;
static constexpr int CMD_CONFIRM_HANDSHAKE_DATA = 0x6400;
static constexpr int ACK_RESPONSE = 0x7300;
static constexpr int ACK_RESPONSE_MASK = 0xFF00;
static constexpr int HEADER_SIZE = 0xC0;
static constexpr int HEADER_PARTS = HEADER_SIZE / 2;
static constexpr auto MAX_BAUD_RATE = LinkRawCable::BaudRate::BAUD_RATE_3;
struct Response {
u32 data[LINK_RAW_CABLE_MAX_PLAYERS];
int playerId = -1; // (-1 = unknown)
};
public:
enum class Result {
SUCCESS,
UNALIGNED,
INVALID_SIZE,
CANCELED,
FAILURE_DURING_TRANSFER
};
enum class TransferMode {
SPI = 0,
MULTI_PLAY = 1
}; // (used in SWI call, do not swap)
/**
* @brief Sends the `rom`. Once completed, the return value should be
* `LinkCableMultiboot::Result::SUCCESS`.
* @param rom A pointer to ROM data. Must be 4-byte aligned.
* @param romSize Size of the ROM in bytes. It must be a number between
* `448` and `262144`, and a multiple of `16`.
* @param cancel A function that will be continuously invoked. If it
* returns `true`, the transfer will be aborted.
* @param mode Either `TransferMode::MULTI_PLAY` for GBA cable (default
* value) or `TransferMode::SPI` for GBC cable.
* \warning Blocks the system until completion or cancellation.
*/
template <typename F>
Result sendRom(const u8* rom,
u32 romSize,
F cancel,
TransferMode mode = TransferMode::MULTI_PLAY) {
LINK_READ_TAG(LINK_CABLE_MULTIBOOT_VERSION);
this->_mode = mode;
if ((u32)rom % 4 != 0)
return Result::UNALIGNED;
if (romSize < MIN_ROM_SIZE || romSize > MAX_ROM_SIZE ||
(romSize % 0x10) != 0)
return Result::INVALID_SIZE;
retry:
stop();
// (*) instead of 1/16s, waiting a random number of frames works better
Link::wait(INITIAL_WAIT_MIN_LINES +
FRAME_LINES *
Link::_qran_range(1, INITIAL_WAIT_MAX_RANDOM_FRAMES));
// 1. Prepare a "Multiboot Parameter Structure" in RAM.
PartialResult partialResult = PartialResult::NEEDS_RETRY;
Link::_MultiBootParam multiBootParameters;
multiBootParameters.client_data[0] = CLIENT_NO_DATA;
multiBootParameters.client_data[1] = CLIENT_NO_DATA;
multiBootParameters.client_data[2] = CLIENT_NO_DATA;
multiBootParameters.palette_data = LINK_CABLE_MULTIBOOT_PALETTE_DATA;
multiBootParameters.client_bit = 0;
multiBootParameters.boot_srcp = (u8*)rom + HEADER_SIZE;
multiBootParameters.boot_endp = (u8*)rom + romSize;
LINK_CABLE_MULTIBOOT_TRY(detectClients(multiBootParameters, cancel))
LINK_CABLE_MULTIBOOT_TRY(sendHeader(multiBootParameters, rom, cancel))
LINK_CABLE_MULTIBOOT_TRY(sendPalette(multiBootParameters, cancel))
LINK_CABLE_MULTIBOOT_TRY(confirmHandshakeData(multiBootParameters, cancel))
// 9. Call SWI 0x25, with r0 set to the address of the multiboot parameter
// structure and r1 set to the communication mode (0 for normal, 1 for
// MultiPlay).
int result = Link::_MultiBoot(&multiBootParameters, (int)_mode);
stop();
// 10. Upon return, r0 will be either 0 for success, or 1 for failure. If
// successful, all clients have received the multiboot program successfully
// and are now executing it - you can begin either further data transfer or
// a multiplayer game from here.
return result == 1 ? Result::FAILURE_DURING_TRANSFER : Result::SUCCESS;
}
private:
LinkRawCable linkRawCable;
LinkSPI linkSPI;
TransferMode _mode;
enum class PartialResult { NEEDS_RETRY, FINISHED, ABORTED };
template <typename F>
PartialResult detectClients(Link::_MultiBootParam& multiBootParameters,
F cancel) {
// 2. Initiate a multiplayer communication session, using either Normal mode
// for a single client or MultiPlay mode for multiple clients.
start();
// 3. Send the word 0x6200 repeatedly until all detected clients respond
// with 0x720X, where X is their client number (1-3). If they fail to do
// this after 16 tries, delay 1/16s and go back to step 2. (*)
bool success = false;
for (u32 t = 0; t < DETECTION_TRIES; t++) {
auto response = transfer(CMD_HANDSHAKE, cancel);
if (cancel())
return PartialResult::ABORTED;
multiBootParameters.client_bit = 0;
success =
validateResponse(response, [&multiBootParameters](u32 i, u16 value) {
if ((value & 0xFFF0) == ACK_HANDSHAKE) {
u8 clientId = value & 0xF;
u8 expectedClientId = 1 << (i + 1);
if (clientId == expectedClientId) {
multiBootParameters.client_bit |= clientId;
return true;
}
}
return false;
});
if (success)
break;
}
if (!success)
return PartialResult::NEEDS_RETRY;
// 4. Fill in client_bit in the multiboot parameter structure (with
// bits 1-3 set according to which clients responded). Send the word
// 0x610Y, where Y is that same set of set bits.
auto response =
transfer(CMD_CONFIRM_CLIENTS | multiBootParameters.client_bit, cancel);
// The clients should respond 0x7200.
if (!isResponseSameAsValueWithClientBit(
response, multiBootParameters.client_bit, ACK_HANDSHAKE))
return PartialResult::NEEDS_RETRY;
return PartialResult::FINISHED;
}
template <typename F>
PartialResult sendHeader(Link::_MultiBootParam& multiBootParameters,
const u8* rom,
F cancel) {
// 5. Send the cartridge header, 16 bits at a time, in little endian order.
// After each 16-bit send, the clients will respond with 0xNN0X, where NN is
// the number of words remaining and X is the client number. (Note that if
// transferring in the single-client 32-bit mode, you still need to send
// only 16 bits at a time).
u16* headerOut = (u16*)rom;
u32 remaining = HEADER_PARTS;
while (remaining > 0) {
auto response = transfer(*(headerOut++), cancel);
if (cancel())
return PartialResult::ABORTED;
if (!isResponseSameAsValueWithClientBit(
response, multiBootParameters.client_bit, remaining << 8))
return PartialResult::NEEDS_RETRY;
remaining--;
}
// 6. Send 0x6200, followed by 0x620Y again.
// The clients should respond 0x000Y and 0x720Y.
Response response;
response = transfer(CMD_HANDSHAKE, cancel);
if (cancel())
return PartialResult::ABORTED;
if (!isResponseSameAsValueWithClientBit(response,
multiBootParameters.client_bit, 0))
return PartialResult::NEEDS_RETRY;
response = transfer(CMD_HANDSHAKE | multiBootParameters.client_bit, cancel);
if (cancel())
return PartialResult::ABORTED;
if (!isResponseSameAsValueWithClientBit(
response, multiBootParameters.client_bit, ACK_HANDSHAKE))
return PartialResult::NEEDS_RETRY;
return PartialResult::FINISHED;
}
template <typename F>
PartialResult sendPalette(Link::_MultiBootParam& multiBootParameters,
F cancel) {
// 7. Send 0x63PP repeatedly, where PP is the palette_data you have picked
// earlier. Do this until the clients respond with 0x73CC, where CC is a
// random byte. Store these bytes in client_data in the parameter structure.
u16 data = CMD_SEND_PALETTE | LINK_CABLE_MULTIBOOT_PALETTE_DATA;
bool success = false;
for (u32 i = 0; i < DETECTION_TRIES; i++) {
auto response = transfer(data, cancel);
if (cancel())
return PartialResult::ABORTED;
u8 sendMask = multiBootParameters.client_bit;
success = validateResponse(
response,
[&multiBootParameters, &sendMask](u32 i, u16 value) {
u8 clientBit = 1 << (i + 1);
if ((multiBootParameters.client_bit & clientBit) &&
((value & ACK_RESPONSE_MASK) == ACK_RESPONSE)) {
multiBootParameters.client_data[i] = value & 0xFF;
sendMask &= ~clientBit;
return true;
}
return false;
}) &&
sendMask == 0;
if (success)
break;
}
if (!success)
return PartialResult::NEEDS_RETRY;
return PartialResult::FINISHED;
}
template <typename F>
PartialResult confirmHandshakeData(Link::_MultiBootParam& multiBootParameters,
F cancel) {
// 8. Calculate the handshake_data byte and store it in the parameter
// structure. This should be calculated as 0x11 + the sum of the three
// client_data bytes. Send 0x64HH, where HH is the handshake_data.
// The clients should respond 0x77GG, where GG is something unimportant.
multiBootParameters.handshake_data =
(HANDSHAKE_DATA + multiBootParameters.client_data[0] +
multiBootParameters.client_data[1] +
multiBootParameters.client_data[2]) %
256;
u16 data = CMD_CONFIRM_HANDSHAKE_DATA | multiBootParameters.handshake_data;
auto response = transfer(data, cancel);
if (cancel())
return PartialResult::ABORTED;
if (!isResponseSameAsValue(response, multiBootParameters.client_bit,
ACK_RESPONSE, ACK_RESPONSE_MASK))
return PartialResult::NEEDS_RETRY;
return PartialResult::FINISHED;
}
template <typename F>
Response transfer(u32 data, F cancel) {
if (_mode == TransferMode::MULTI_PLAY) {
Response response;
auto response16bit = linkRawCable.transfer(data, cancel);
for (u32 i = 0; i < LINK_RAW_CABLE_MAX_PLAYERS; i++)
response.data[i] = response16bit.data[i];
response.playerId = response16bit.playerId;
return response;
} else {
Response response = {
.data = {LINK_RAW_CABLE_DISCONNECTED, LINK_RAW_CABLE_DISCONNECTED,
LINK_RAW_CABLE_DISCONNECTED, LINK_RAW_CABLE_DISCONNECTED}};
response.data[1] = linkSPI.transfer(data, cancel) >> 16;
response.playerId = 0;
return response;
}
}
void start() {
if (_mode == TransferMode::MULTI_PLAY)
linkRawCable.activate(MAX_BAUD_RATE);
else
linkSPI.activate(LinkSPI::Mode::MASTER_256KBPS);
}
void stop() {
if (_mode == TransferMode::MULTI_PLAY)
linkRawCable.deactivate();
else
linkSPI.deactivate();
}
Result error(Result error) {
stop();
return error;
}
static bool isResponseSameAsValue(Response response,
u8 clientMask,
u16 wantedValue,
u16 mask = 0xFFFF) {
return validateResponse(
response, [&clientMask, &wantedValue, &mask](u32 i, u32 value) {
u8 clientBit = 1 << (i + 1);
bool isInvalid =
(clientMask & clientBit) && ((value & mask) != wantedValue);
return !isInvalid;
});
}
static bool isResponseSameAsValueWithClientBit(Response response,
u8 clientMask,
u32 wantedValue) {
return validateResponse(
response, [&clientMask, &wantedValue](u32 i, u32 value) {
u8 clientBit = 1 << (i + 1);
bool isInvalid =
(clientMask & clientBit) && (value != (wantedValue | clientBit));
return !isInvalid;
});
}
template <typename F>
static bool validateResponse(Response response, F check) {
u32 count = 0;
for (u32 i = 0; i < MAX_CLIENTS; i++) {
u32 value = response.data[1 + i];
if (value == LINK_RAW_CABLE_DISCONNECTED) {
// Note that throughout this process, any clients that are not
// connected will always respond with 0xFFFF - be sure to ignore them.
continue;
}
if (!check(i, value))
return false;
count++;
}
return count > 0;
}
public:
/**
* @brief [Asynchronous version] A Multiboot tool to send small programs from
* one GBA to up to 3 slaves.
*/
class Async : Link::AsyncMultiboot {
private:
static constexpr int FPS = 60;
static constexpr int WAIT_BEFORE_MAIN_TRANSFER_FRAMES = 4;
static constexpr int CRCC_MULTI_START = 0xFFF8;
static constexpr int CRCC_NORMAL_START = 0xC387;
static constexpr int CRCC_MULTI_XOR = 0xA517;
static constexpr int CRCC_NORMAL_XOR = 0xC37B;
static constexpr u32 DATA_MULTI_XOR = 0x6465646F;
static constexpr u32 DATA_NORMAL_XOR = 0x43202F2F;
static constexpr u32 SEED_MULTIPLIER = 0x6F646573;
static constexpr int CMD_ROM_END = 0x0065;
static constexpr int ACK_ROM_END = 0x0075;
static constexpr int CMD_FINAL_CRC = 0x0066;
static constexpr int MAX_FINAL_HANDSHAKE_ATTEMPS = FPS * 5;
static constexpr int MAX_IRQ_TIMEOUT_FRAMES = FPS * 1;
public:
using GeneralResult = Link::AsyncMultiboot::Result;
enum class State {
STOPPED = 0,
WAITING = 1,
DETECTING_CLIENTS = 2,
DETECTING_CLIENTS_END = 3,
SENDING_HEADER = 4,
SENDING_PALETTE = 5,
CONFIRMING_HANDSHAKE_DATA = 6,
WAITING_BEFORE_MAIN_TRANSFER = 7,
CALCULATING_CRCB = 8,
SENDING_ROM = 9,
SENDING_ROM_END = 10,
SENDING_ROM_END_WAITING = 11,
SENDING_FINAL_CRC = 12,
CHECKING_FINAL_CRC = 13
};
enum class Result {
NONE = -1,
SUCCESS = 0,
UNALIGNED = 1,
INVALID_SIZE = 2,
SEND_FAILURE = 3,
FINAL_HANDSHAKE_FAILURE = 4,
CRC_FAILURE = 5,
};
/**
* @brief Constructs a new LinkCableMultiboot::Async object.
* @param waitForReadySignal Whether the code should wait for a
* `markReady()` call to start the actual transfer.
* @param mode Either `TransferMode::MULTI_PLAY` for GBA cable (default
* value) or `TransferMode::SPI` for GBC cable.
*/
explicit Async(bool waitForReadySignal = false,
TransferMode mode = TransferMode::MULTI_PLAY) {
config.waitForReadySignal = waitForReadySignal;
config.mode = mode;
}
/**
* @brief Sends the `rom`. Once completed, `getState()` should return
* `LinkCableMultiboot::Async::State::STOPPED` and `getResult()` should
* return `LinkCableMultiboot::Async::GeneralResult::SUCCESS`. Returns
* `false` if there's a pending transfer or the data is invalid.
* @param rom A pointer to ROM data. Must be 4-byte aligned.
* @param romSize Size of the ROM in bytes. It must be a number between
* `448` and `262144`, and a multiple of `16`.
*/
bool sendRom(const u8* rom, u32 romSize) override {
if (state != State::STOPPED)
return false;
if ((u32)rom % 4 != 0) {
result = Result::UNALIGNED;
return false;
}
if (romSize < MIN_ROM_SIZE || romSize > MAX_ROM_SIZE ||
(romSize % 0x10) != 0) {
result = Result::INVALID_SIZE;
return false;
}
resetState();
initFixedData(rom, romSize, config.waitForReadySignal, config.mode);
startMultibootSend();
return true;
}
/**
* @brief Deactivates the library, canceling the in-progress transfer, if
* any.
* \warning Never call this method inside an interrupt handler!
*/
bool reset() override {
stop();
return true;
}
/**
* @brief Returns whether there's an active transfer or not.
*/
[[nodiscard]] bool isSending() override { return state != State::STOPPED; }
/**
* @brief Returns the current state.
*/
[[nodiscard]] State getState() { return state; }
/**
* @brief Returns the result of the last operation. After this
* call, the result is cleared if `clear` is `true` (default behavior).
* @param clear Whether it should clear the result or not.
*/
Link::AsyncMultiboot::Result getResult(bool clear = true) override {
auto detailedResult = getDetailedResult(clear);
switch (detailedResult) {
case Result::NONE:
return Link::AsyncMultiboot::Result::NONE;
case Result::SUCCESS:
return Link::AsyncMultiboot::Result::SUCCESS;
case Result::UNALIGNED:
case Result::INVALID_SIZE:
return Link::AsyncMultiboot::Result::INVALID_DATA;
default:
return Link::AsyncMultiboot::Result::FAILURE;
}
}
/**
* @brief Returns the detailed result of the last operation. After this
* call, the result is cleared if `clear` is `true` (default behavior).
* @param clear Whether it should clear the result or not.
*/
Result getDetailedResult(bool clear = true) {
Result _result = result;
if (clear)
result = Result::NONE;
return _result;
}
/**
* @brief Returns the number of connected players (`1~4`).
*/
[[nodiscard]] u8 playerCount() override {
return dynamicData.confirmedObservedPlayers;
}
/**
* @brief Returns the completion percentage (0~100).
*/
[[nodiscard]] u8 getPercentage() override {
if (state == State::STOPPED || fixedData.romSize == 0)
return 0;
return Link::_min(
dynamicData.currentRomPart * 100 / (fixedData.romSize / 4), 100);
}
/**
* @brief Returns whether the ready mark is active or not.
* \warning This is only useful when using the `waitForReadySignal`
* parameter.
*/
[[nodiscard]] bool isReady() override { return dynamicData.ready; }
/**
* @brief Marks the transfer as ready.
* \warning This is only useful when using the `waitForReadySignal`
* parameter.
*/
void markReady() override {
if (state == State::STOPPED)
return;
dynamicData.ready = true;
}
/**
* @brief This method is called by the VBLANK interrupt handler.
* \warning This is internal API!
*/
void _onVBlank() {
if (state == State::STOPPED)
return;
processNewFrame();
}
/**
* @brief This method is called by the SERIAL interrupt handler.
* \warning This is internal API!
*/
void _onSerial() {
if (state == State::STOPPED || interrupt)
return;
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
interrupt = true;
#endif
Response response = getAsyncResponse();
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
Link::_REG_IME = 1;
#endif
processResponse(response);
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
interrupt = false;
#endif
}
struct Config {
bool waitForReadySignal = false;
TransferMode mode = TransferMode::MULTI_PLAY;
};
/**
* @brief LinkCableMultiboot::Async configuration.
* \warning `deactivate()` first, change the config, and `activate()` again!
*/
Config config;
private:
struct MultibootFixedData {
const u16* rom = nullptr;
vu32 romSize = 0;
bool waitForReadySignal = false;
TransferMode transferMode = TransferMode::MULTI_PLAY;
};
struct MultibootDynamicData {
vu8 clientMask = 0;
u32 crcB = 0;
u32 seed = 0;
u32 crcC = 0;
u32 irqTimeout = 0;
u32 waitFrames = 0;
u32 wait = 0;
u32 tryCount = 0;
u32 headerRemaining = 0;
vu32 currentRomPart = 0;
bool currentRomPartSecondHalf = false;
bool ready = false;
u32 observedPlayers = 1;
u32 confirmedObservedPlayers = 1;
};
LinkRawCable linkRawCable;
LinkSPI linkSPI;
MultibootFixedData fixedData;
MultibootDynamicData dynamicData;
volatile State state = State::STOPPED;
volatile Result result = Result::NONE;
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
volatile bool interrupt = false;
#endif
void processNewFrame() {
dynamicData.irqTimeout++;
if (dynamicData.irqTimeout >= MAX_IRQ_TIMEOUT_FRAMES) {
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
if (!interrupt)
#endif
startMultibootSend();
return;
}
switch (state) {
case State::WAITING: {
dynamicData.wait++;
if (dynamicData.wait >= dynamicData.waitFrames) {
state = State::DETECTING_CLIENTS;
start();
transferAsync(CMD_HANDSHAKE);
}
break;
}
case State::WAITING_BEFORE_MAIN_TRANSFER: {
dynamicData.wait++;
if (dynamicData.wait >= dynamicData.waitFrames) {
state = State::CALCULATING_CRCB;
transferAsync((fixedData.romSize - 0x190) / 4);
}
break;
}
case State::SENDING_ROM_END_WAITING: {
state = State::SENDING_ROM_END;
dynamicData.tryCount++;
if (dynamicData.tryCount >= MAX_FINAL_HANDSHAKE_ATTEMPS)
return (void)stop(Result::FINAL_HANDSHAKE_FAILURE);
transferAsync(CMD_ROM_END);
}
default: {
}
}
}
void processResponse(Response response) {
dynamicData.irqTimeout = 0;
switch (state) {
case State::DETECTING_CLIENTS: {
u32 players = 1;
dynamicData.clientMask = 0;
bool success =
validateResponse(response, [this, &players](u32 i, u16 value) {
if ((value & 0xFFF0) == ACK_HANDSHAKE) {
u8 clientId = value & 0xF;
u8 expectedClientId = 1 << (i + 1);
if (clientId == expectedClientId) {
dynamicData.clientMask |= clientId;
players++;
return true;
}
}
return false;
});
dynamicData.observedPlayers = players;
if (success) {
state = State::DETECTING_CLIENTS_END;
transferAsync(CMD_CONFIRM_CLIENTS | dynamicData.clientMask);
} else {
dynamicData.tryCount++;
if (dynamicData.tryCount >= DETECTION_TRIES)
return (void)startMultibootSend();
transferAsync(CMD_HANDSHAKE);
}
break;
}
case State::DETECTING_CLIENTS_END: {
if (!isResponseSameAsValueWithClientBit(
response, dynamicData.clientMask, ACK_HANDSHAKE))
return (void)startMultibootSend();
dynamicData.confirmedObservedPlayers = dynamicData.observedPlayers;
if (fixedData.waitForReadySignal && !dynamicData.ready)
return (void)startMultibootSend();
state = State::SENDING_HEADER;
dynamicData.headerRemaining = HEADER_PARTS;
sendHeaderPart();
break;
}
case State::SENDING_HEADER: {
if (!isResponseSameAsValueWithClientBit(
response, dynamicData.clientMask,
dynamicData.headerRemaining << 8))
return (void)startMultibootSend();
dynamicData.headerRemaining--;
sendHeaderPart();
break;
}
case State::SENDING_PALETTE: {
u8 sendMask = dynamicData.clientMask;
u8 clientData[3] = {CLIENT_NO_DATA, CLIENT_NO_DATA, CLIENT_NO_DATA};
bool success =
validateResponse(
response,
[this, &sendMask, &clientData](u32 i, u16 value) {
u8 clientBit = 1 << (i + 1);
if ((dynamicData.clientMask & clientBit) &&
((value & ACK_RESPONSE_MASK) == ACK_RESPONSE)) {
clientData[i] = value & 0xFF;
sendMask &= ~clientBit;
return true;
}
return false;
}) &&
sendMask == 0;
if (success) {
state = State::CONFIRMING_HANDSHAKE_DATA;
u8 handshakeData = HANDSHAKE_DATA;
dynamicData.seed = LINK_CABLE_MULTIBOOT_PALETTE_DATA;
for (u32 i = 0; i < MAX_CLIENTS; i++) {
handshakeData += clientData[i];
dynamicData.seed |= clientData[i] << (8 * (i + 1));
}
handshakeData &= 0xFF;
dynamicData.crcB = handshakeData;
transferAsync(CMD_CONFIRM_HANDSHAKE_DATA | handshakeData);
} else {
dynamicData.tryCount++;
if (dynamicData.tryCount >= DETECTION_TRIES)
return (void)startMultibootSend();
sendPaletteData();
}
break;
}
case State::CONFIRMING_HANDSHAKE_DATA: {
if (!isResponseSameAsValue(response, dynamicData.clientMask,
ACK_RESPONSE, ACK_RESPONSE_MASK))
return (void)startMultibootSend();
state = State::WAITING_BEFORE_MAIN_TRANSFER;
dynamicData.waitFrames = WAIT_BEFORE_MAIN_TRANSFER_FRAMES;
break;
}
case State::CALCULATING_CRCB: {
for (u32 i = 0; i < MAX_CLIENTS; i++) {
u8 clientBit = 1 << (i + 1);
u8 contribute = 0xFF;
if (dynamicData.clientMask & clientBit)
contribute = response.data[1 + i] & 0xFF;
dynamicData.crcB |= contribute << (8 * (i + 1));
}
state = State::SENDING_ROM;
dynamicData.crcC = fixedData.transferMode == TransferMode::MULTI_PLAY
? CRCC_MULTI_START
: CRCC_NORMAL_START;
dynamicData.currentRomPart = HEADER_SIZE / 4;
sendRomPart();
break;
}
case State::SENDING_ROM: {
u32* dataOut = (u32*)fixedData.rom;
if (fixedData.transferMode == TransferMode::MULTI_PLAY) {
if (!dynamicData.currentRomPartSecondHalf) {
if (!isResponseSameAsValue(response, dynamicData.clientMask,
dynamicData.currentRomPart << 2))
return (void)stop(Result::SEND_FAILURE);
dynamicData.currentRomPartSecondHalf = true;
sendRomPart();
return;
} else {
if (!isResponseSameAsValue(response, dynamicData.clientMask,
(dynamicData.currentRomPart << 2) + 2))
return (void)stop(Result::SEND_FAILURE);
}
} else {
if (!isResponseSameAsValue(response, dynamicData.clientMask,
dynamicData.currentRomPart << 2))
return (void)stop(Result::SEND_FAILURE);
}
calculateCRCData(dataOut[dynamicData.currentRomPart]);
dynamicData.currentRomPart++;
dynamicData.currentRomPartSecondHalf = false;
sendRomPart();
break;
}
case State::SENDING_ROM_END: {
bool success = isResponseSameAsValue(response, dynamicData.clientMask,
ACK_ROM_END);
if (success) {
state = State::SENDING_FINAL_CRC;
transferAsync(CMD_FINAL_CRC);
} else {
state = State::SENDING_ROM_END_WAITING;
}
break;
}
case State::SENDING_FINAL_CRC: {
state = State::CHECKING_FINAL_CRC;
transferAsync(dynamicData.crcC);
break;
}
case State::CHECKING_FINAL_CRC: {
if (!isResponseSameAsValue(response, dynamicData.clientMask,
dynamicData.crcC))
return (void)stop(Result::CRC_FAILURE);
stop(Result::SUCCESS);
break;
}
default: {
}
}
}
void initFixedData(const u8* rom,
u32 romSize,
bool waitForReadySignal,
TransferMode mode) {
const u16* start = (u16*)rom;
const u16* end = (u16*)(rom + romSize);
fixedData.rom = start;
fixedData.romSize = (u32)end - (u32)start;
fixedData.waitForReadySignal = waitForReadySignal;
fixedData.transferMode = mode;
}
void startMultibootSend() {
auto tmpFixedData = fixedData;
bool tmpReady = dynamicData.ready;
u32 tmpConfirmedObservedPlayers = dynamicData.confirmedObservedPlayers;
stop();
state = State::WAITING;
fixedData = tmpFixedData;
dynamicData.ready = tmpReady;
dynamicData.confirmedObservedPlayers = tmpConfirmedObservedPlayers;
dynamicData.waitFrames =
INITIAL_WAIT_MIN_FRAMES +
Link::_qran_range(1, INITIAL_WAIT_MAX_RANDOM_FRAMES);
}
void sendHeaderPart() {
if (dynamicData.headerRemaining <= 0) {
state = State::SENDING_PALETTE;
dynamicData.tryCount = 0;
sendPaletteData();
return;
}
transferAsync(fixedData.rom[HEADER_PARTS - dynamicData.headerRemaining]);
}
void sendPaletteData() {
transferAsync(CMD_SEND_PALETTE | LINK_CABLE_MULTIBOOT_PALETTE_DATA);
}
void sendRomPart() {
u32* dataOut = (u32*)fixedData.rom;
u32 i = dynamicData.currentRomPart;
if (i >= fixedData.romSize / 4) {
dynamicData.crcC &= 0xFFFF;
calculateCRCData(dynamicData.crcB);
state = State::SENDING_ROM_END;
dynamicData.tryCount = 0;
transferAsync(CMD_ROM_END);
return;
}
if (!dynamicData.currentRomPartSecondHalf)
dynamicData.seed = (dynamicData.seed * SEED_MULTIPLIER) + 1;
u32 baseData = dataOut[i] ^ (0xFE000000 - (i << 2)) ^ dynamicData.seed;
if (fixedData.transferMode == TransferMode::MULTI_PLAY) {
u32 data = baseData ^ DATA_MULTI_XOR;
if (!dynamicData.currentRomPartSecondHalf)
transferAsync(data & 0xFFFF);
else
transferAsync(data >> 16);
} else {
transferAsync(baseData ^ DATA_NORMAL_XOR);
}
}
void calculateCRCData(u32 readData) {
u32 tmpCrcC = dynamicData.crcC;
u32 xorVal = fixedData.transferMode == TransferMode::MULTI_PLAY
? CRCC_MULTI_XOR
: CRCC_NORMAL_XOR;
for (u32 i = 0; i < 32; i++) {
u8 bit = (tmpCrcC ^ readData) & 1;
readData >>= 1;
tmpCrcC >>= 1;
if (bit)
tmpCrcC ^= xorVal;
}
dynamicData.crcC = tmpCrcC;
}
void resetState(Result newResult = Result::NONE) {
LINK_BARRIER;
state = State::STOPPED;
result = newResult;
fixedData = MultibootFixedData{};
dynamicData = MultibootDynamicData{};
LINK_BARRIER;
}
Response getAsyncResponse() {
Response response = {
.data = {LINK_RAW_CABLE_DISCONNECTED, LINK_RAW_CABLE_DISCONNECTED,
LINK_RAW_CABLE_DISCONNECTED, LINK_RAW_CABLE_DISCONNECTED}};
if (fixedData.transferMode == TransferMode::MULTI_PLAY) {
linkRawCable._onSerial();
auto response16bit = linkRawCable.getAsyncData();
for (u32 i = 0; i < LINK_RAW_CABLE_MAX_PLAYERS; i++)
response.data[i] = response16bit.data[i];
response.playerId = response16bit.playerId;
} else {
linkSPI._onSerial();
response.data[1] = linkSPI.getAsyncData() >> 16;
response.playerId = 0;
}
return response;
}
void transferAsync(u32 data) {
#ifndef LINK_CABLE_MULTIBOOT_ASYNC_DISABLE_NESTED_IRQ
Link::_REG_IME = 0;
#endif
if (fixedData.transferMode == TransferMode::MULTI_PLAY)
linkRawCable.transferAsync(data);
else
linkSPI.transferAsync(data);
}
void start() {
if (fixedData.transferMode == TransferMode::MULTI_PLAY)
linkRawCable.activate(MAX_BAUD_RATE);
else
linkSPI.activate(LinkSPI::Mode::MASTER_256KBPS);
}
void stop(Result newResult = Result::NONE) {
auto mode = fixedData.transferMode;
resetState(newResult);
if (mode == TransferMode::MULTI_PLAY)
linkRawCable.deactivate();
else
linkSPI.deactivate();
}
};
};
extern LinkCableMultiboot* linkCableMultiboot;
extern LinkCableMultiboot::Async* linkCableMultibootAsync;
/**
* @brief VBLANK interrupt handler.
*/
inline void LINK_CABLE_MULTIBOOT_ASYNC_ISR_VBLANK() {
linkCableMultibootAsync->_onVBlank();
}
/**
* @brief SERIAL interrupt handler.
*/
inline void LINK_CABLE_MULTIBOOT_ASYNC_ISR_SERIAL() {
linkCableMultibootAsync->_onSerial();
}
#endif // LINK_CABLE_MULTIBOOT_H