Refactored program memory writes in WCH-Link driver
This commit is contained in:
Nav
@@ -218,132 +218,42 @@ namespace DebugToolDrivers::Wch
|
||||
) {
|
||||
if (memorySegmentDescriptor.type == TargetMemorySegmentType::FLASH) {
|
||||
/*
|
||||
* WCH-Link tools cannot write to flash memory via the target's debug module. They do, however, offer a
|
||||
* set of dedicated commands for this. We invoke them here.
|
||||
*
|
||||
* There are two commands we can choose from:
|
||||
* WCH-Link tools provide two dedicated commands for writing to flash memory:
|
||||
*
|
||||
* - Partial block write
|
||||
* Writes any number of bytes to flash, but limited to a maximum of 64 bytes per write. Larger writes
|
||||
* must be split into multiple writes.
|
||||
* Writes any number of 16-bit-aligned bytes to flash, but limited to a maximum of 64 bytes per write -
|
||||
* larger writes must be split into multiple writes. Can only access a single page at a time - writes
|
||||
* which span multiple pages must be split into multiple writes.
|
||||
* - Full block write
|
||||
* Writes an entire block to flash, where the block size is target-specific (resides in the target's
|
||||
* TDF). Requires alignment to the block size. Requires reattaching to the target at the end of the
|
||||
* programming session.
|
||||
* TDF) and is typically equal to 16 pages. Requires alignment to the block size. Requires reattaching
|
||||
* to the target at the end of the write operation.
|
||||
*
|
||||
* The full block write is much faster for writing large buffers (KiBs), such as when we're programming
|
||||
* the target. But the partial block write is faster and more suitable for writing buffers that are
|
||||
* smaller than 64 bytes, such as when we're inserting software breakpoints.
|
||||
*/
|
||||
const auto bufferSize = static_cast<TargetMemorySize>(buffer.size());
|
||||
const auto alignmentSize = this->programmingBlockSize;
|
||||
const auto alignedStartAddress = (startAddress / alignmentSize) * alignmentSize;
|
||||
const auto alignedBufferSize = static_cast<TargetMemorySize>(std::ceil(
|
||||
static_cast<double>(bufferSize) / static_cast<double>(alignmentSize)
|
||||
) * alignmentSize);
|
||||
const auto alignmentRequired = alignedStartAddress != startAddress || alignedBufferSize != bufferSize;
|
||||
|
||||
if (
|
||||
bufferSize <= WchLinkInterface::MAX_PARTIAL_BLOCK_WRITE_SIZE
|
||||
|| (
|
||||
alignmentRequired
|
||||
&& !memorySegmentDescriptor.addressRange.contains(
|
||||
TargetMemoryAddressRange{
|
||||
alignedStartAddress,
|
||||
alignedStartAddress + alignedBufferSize - 1
|
||||
}
|
||||
)
|
||||
)
|
||||
buffer.size() <= WchLinkInterface::MAX_PARTIAL_BLOCK_WRITE_SIZE
|
||||
|| !this->fullBlockWriteCompatible(addressSpaceDescriptor, memorySegmentDescriptor, startAddress)
|
||||
) {
|
||||
using namespace ::DebugToolDrivers::Protocols::RiscVDebugSpec;
|
||||
Logger::debug("Using partial block write command");
|
||||
|
||||
/*
|
||||
* WCH-Link tools seem to make use of the target's program buffer to service the partial block write
|
||||
* command.
|
||||
*
|
||||
* This sometimes leads to exceptions occurring on the target, when the program buffer contains certain
|
||||
* instructions before the partial block write command is invoked. This is why we clear the program
|
||||
* buffer beforehand.
|
||||
*/
|
||||
this->riscVTranslator.clearProgramBuffer();
|
||||
this->wchLinkInterface.writeFlashPartialBlock(startAddress, buffer);
|
||||
|
||||
const auto commandError = this->riscVTranslator.readAndClearAbstractCommandError();
|
||||
if (commandError != DebugModule::AbstractCommandError::NONE) {
|
||||
throw Exception{
|
||||
"Partial block write failed - abstract command error: 0x"
|
||||
+ Services::StringService::toHex(commandError)
|
||||
};
|
||||
}
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
if (alignmentRequired) {
|
||||
auto alignedBuffer = (alignedStartAddress < startAddress)
|
||||
? this->readMemory(
|
||||
Logger::debug("Using partial block write method");
|
||||
return this->writeProgramMemoryPartialBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedStartAddress,
|
||||
(startAddress - alignedStartAddress),
|
||||
{}
|
||||
)
|
||||
: TargetMemoryBuffer{};
|
||||
|
||||
alignedBuffer.resize(alignedBufferSize);
|
||||
|
||||
std::copy(
|
||||
buffer.begin(),
|
||||
buffer.end(),
|
||||
alignedBuffer.begin() + (startAddress - alignedStartAddress)
|
||||
);
|
||||
|
||||
const auto dataBack = this->readMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
startAddress + bufferSize,
|
||||
alignedBufferSize - bufferSize - (startAddress - alignedStartAddress),
|
||||
{}
|
||||
);
|
||||
std::copy(
|
||||
dataBack.begin(),
|
||||
dataBack.end(),
|
||||
alignedBuffer.begin() + (startAddress - alignedStartAddress) + bufferSize
|
||||
);
|
||||
|
||||
return this->writeMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedStartAddress,
|
||||
alignedBuffer
|
||||
);
|
||||
}
|
||||
|
||||
Logger::debug(
|
||||
"Using full block write command (block size: " + std::to_string(this->programmingBlockSize) + ")"
|
||||
);
|
||||
this->wchLinkInterface.writeFlashFullBlocks(
|
||||
startAddress,
|
||||
buffer,
|
||||
this->programmingBlockSize,
|
||||
this->flashProgramOpcodes
|
||||
buffer
|
||||
);
|
||||
}
|
||||
|
||||
/*
|
||||
* Would this not be better placed in endProgrammingSession()? We could persist the command type we invoked
|
||||
* to perform the write, and if required, reattach at the end of the programming session.
|
||||
*
|
||||
* I don't think that would work, because the target needs to be accessible for other operations whilst in
|
||||
* programming mode. We may perform other operations in between program memory writes, but that wouldn't
|
||||
* work if we left the target in an inaccessible state between writes. So I think we have to reattach here.
|
||||
*
|
||||
* TODO: Review after v2.0.0.
|
||||
*/
|
||||
this->deactivate();
|
||||
this->wchLinkInterface.sendCommandAndWaitForResponse(Commands::Control::GetDeviceInfo{});
|
||||
this->activate();
|
||||
return;
|
||||
Logger::debug("Using full block write method");
|
||||
return this->writeProgramMemoryFullBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
startAddress,
|
||||
buffer
|
||||
);
|
||||
}
|
||||
|
||||
this->riscVTranslator.writeMemory(
|
||||
@@ -477,6 +387,319 @@ namespace DebugToolDrivers::Wch
|
||||
this->softwareBreakpointRegistry.remove(softwareBreakpoint);
|
||||
}
|
||||
|
||||
void WchLinkDebugInterface::writeProgramMemoryPartialBlock(
|
||||
const TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
Targets::TargetMemoryAddress startAddress,
|
||||
Targets::TargetMemoryBufferSpan buffer
|
||||
) {
|
||||
using Services::AlignmentService;
|
||||
using namespace ::DebugToolDrivers::Protocols::RiscVDebugSpec;
|
||||
|
||||
if (buffer.empty()) {
|
||||
return;
|
||||
}
|
||||
|
||||
const auto bufferSize = static_cast<TargetMemorySize>(buffer.size());
|
||||
const auto addressRange = TargetMemoryAddressRange{startAddress, startAddress + bufferSize - 1};
|
||||
assert(memorySegmentDescriptor.addressRange.contains(addressRange));
|
||||
|
||||
/*
|
||||
* Partial block writes can only write to a single flash page at a time. If a write operation spans multiple
|
||||
* pages, the WCH-Link tool will write to the first page and ignore the rest, without reporting any error.
|
||||
*
|
||||
* We must break down write operations that span multiple pages.
|
||||
*/
|
||||
assert(memorySegmentDescriptor.pageSize.has_value());
|
||||
const auto pages = addressRange.blocks(*memorySegmentDescriptor.pageSize);
|
||||
if (pages.size() > 1) {
|
||||
for (const auto& pageAddressRange : pages) {
|
||||
this->writeProgramMemoryPartialBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
pageAddressRange.startAddress,
|
||||
buffer.subspan(
|
||||
pageAddressRange.startAddress - addressRange.startAddress,
|
||||
pageAddressRange.size()
|
||||
)
|
||||
);
|
||||
}
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
// Partial block write operations must be 16-bit aligned.
|
||||
static constexpr auto ALIGNMENT_SIZE = 2;
|
||||
const auto alignedAddressRange = AlignmentService::alignAddressRange(addressRange, ALIGNMENT_SIZE);
|
||||
|
||||
if (alignedAddressRange != addressRange) {
|
||||
const auto alignedBufferSize = alignedAddressRange.size();
|
||||
const auto addressAlignmentBytes = static_cast<TargetMemorySize>(
|
||||
addressRange.startAddress - alignedAddressRange.startAddress
|
||||
);
|
||||
const auto sizeAlignmentBytes = alignedBufferSize - bufferSize - addressAlignmentBytes;
|
||||
|
||||
auto alignedBuffer = addressAlignmentBytes > 0
|
||||
? this->readMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedAddressRange.startAddress,
|
||||
addressAlignmentBytes,
|
||||
{}
|
||||
)
|
||||
: TargetMemoryBuffer{};
|
||||
|
||||
alignedBuffer.resize(alignedBufferSize);
|
||||
|
||||
std::copy(buffer.begin(), buffer.end(), alignedBuffer.begin() + addressAlignmentBytes);
|
||||
|
||||
if (sizeAlignmentBytes > 0) {
|
||||
const auto dataBack = this->readMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
addressRange.startAddress + bufferSize,
|
||||
sizeAlignmentBytes,
|
||||
{}
|
||||
);
|
||||
std::copy(
|
||||
dataBack.begin(),
|
||||
dataBack.end(),
|
||||
alignedBuffer.begin() + addressAlignmentBytes + bufferSize
|
||||
);
|
||||
}
|
||||
|
||||
return this->writeProgramMemoryPartialBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedAddressRange.startAddress,
|
||||
alignedBuffer
|
||||
);
|
||||
}
|
||||
|
||||
/*
|
||||
* WCH-Link tools seem to make use of the target's program buffer to service the partial block write
|
||||
* command.
|
||||
*
|
||||
* This sometimes leads to exceptions occurring on the target, when the program buffer contains certain
|
||||
* instructions before the partial block write command is invoked. This is why we clear the program buffer
|
||||
* beforehand.
|
||||
*/
|
||||
this->riscVTranslator.clearProgramBuffer();
|
||||
this->wchLinkInterface.writeFlashPartialBlock(startAddress, buffer);
|
||||
|
||||
/*
|
||||
* Sometimes, when delegating part of a full block write operation to the partial block write method, a "busy"
|
||||
* error occurs. However, this doesn't seem to affect the outcome of the operation at all.
|
||||
*
|
||||
* This only seems to happen when writing to the boot segment of the CH32V003, shortly after a full block write
|
||||
* has taken place. It doesn't happen in the absence of a full block write.
|
||||
*
|
||||
* I suspect the tool may be attempting to verify the newly written data, and that is what's failing. But I
|
||||
* really don't know.
|
||||
*
|
||||
* For now, I think it's safe to ignore the "busy" error.
|
||||
*/
|
||||
const auto commandError = this->riscVTranslator.readAndClearAbstractCommandError();
|
||||
if (
|
||||
commandError != DebugModule::AbstractCommandError::NONE
|
||||
&& commandError != DebugModule::AbstractCommandError::BUSY
|
||||
) {
|
||||
throw Exception{
|
||||
"Partial block write failed - abstract command error: 0x"
|
||||
+ Services::StringService::toHex(commandError)
|
||||
};
|
||||
}
|
||||
}
|
||||
|
||||
void WchLinkDebugInterface::writeProgramMemoryFullBlock(
|
||||
const TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
Targets::TargetMemoryAddress startAddress,
|
||||
Targets::TargetMemoryBufferSpan buffer
|
||||
) {
|
||||
using Services::AlignmentService;
|
||||
using Services::StringService;
|
||||
using namespace ::DebugToolDrivers::Protocols::RiscVDebugSpec;
|
||||
|
||||
if (buffer.empty()) {
|
||||
return;
|
||||
}
|
||||
|
||||
const auto bufferSize = static_cast<TargetMemorySize>(buffer.size());
|
||||
const auto addressRange = TargetMemoryAddressRange{startAddress, startAddress + bufferSize - 1};
|
||||
assert(memorySegmentDescriptor.addressRange.contains(addressRange));
|
||||
|
||||
auto alignedAddressRange = AlignmentService::alignAddressRange(addressRange, this->programmingBlockSize);
|
||||
if (alignedAddressRange != addressRange) {
|
||||
/*
|
||||
* The memory segment capacity may not be a multiple of the (target-specific) block size, meaning alignment
|
||||
* to the block size could result in breaching the boundary of the segment.
|
||||
*
|
||||
* For example, the CH32X035 has a block size of 4096, but its main program segment (`main_program`) has a
|
||||
* capacity of 62KiB (63488 bytes), which is not a multiple of 4096. This means we cannot access the final,
|
||||
* partial block of that segment, via a full block write.
|
||||
*
|
||||
* Some segments on some WCH RISC-V targets don't even have the capacity to accommodate the block size.
|
||||
*
|
||||
* This makes me suspect that
|
||||
* 1. I may be using the wrong block size, and the actual size is smaller, or
|
||||
* 2. Memory segment capacities could be wrong. I obtained these from the target datasheet.
|
||||
*
|
||||
* I have already tried experimenting with smaller block sizes, but nothing has worked. The WCH-Link tool
|
||||
* seems to expect these exact sizes before it will begin the full block write operation.
|
||||
*
|
||||
* Anyway, if the alignment results in the segment boundary being breached, we delegate the final part
|
||||
* of the write operation to the partial block write method, which only requires 16-bit alignment.
|
||||
*
|
||||
* In other words, we will write as many blocks as we can with the full block write method, and then write
|
||||
* the final part with the partial block write method. This allows us to benefit from the performance of
|
||||
* full block writes, whilst maintaining the ability to access the entire segment.
|
||||
*/
|
||||
auto delegatedBytes = TargetMemorySize{0};
|
||||
if (!memorySegmentDescriptor.addressRange.contains(alignedAddressRange)) {
|
||||
Logger::debug(
|
||||
"Alignment to the block size (" + std::to_string(this->programmingBlockSize)
|
||||
+ ") has resulted in a segment boundary breach"
|
||||
);
|
||||
|
||||
alignedAddressRange.endAddress -= this->programmingBlockSize;
|
||||
|
||||
/*
|
||||
* This function isn't designed to handle instances where the entire write operation needs to be
|
||||
* delegated. In such instances, this function should not be called at all. The following assertion
|
||||
* enforces this.
|
||||
*
|
||||
* The WchLinkDebugInterface::fullBlockWriteCompatible() function will determine if at least part of
|
||||
* the operation can be performed using the full block write method.
|
||||
*/
|
||||
assert(alignedAddressRange.intersectsWith(addressRange));
|
||||
|
||||
delegatedBytes = addressRange.endAddress - alignedAddressRange.endAddress;
|
||||
|
||||
Logger::debug(
|
||||
"The full block write has been reduced to " + std::to_string(alignedAddressRange.size())
|
||||
+ " byte(s), from 0x" + StringService::toHex(alignedAddressRange.startAddress)
|
||||
);
|
||||
Logger::debug(std::to_string(delegatedBytes) + " byte(s) will be delegated to a partial write");
|
||||
}
|
||||
|
||||
const auto alignedBufferSize = alignedAddressRange.size();
|
||||
const auto addressAlignmentBytes = static_cast<TargetMemorySize>(
|
||||
startAddress - alignedAddressRange.startAddress
|
||||
);
|
||||
const auto sizeAlignmentBytes = (alignedAddressRange.endAddress > addressRange.endAddress)
|
||||
? alignedAddressRange.endAddress - addressRange.endAddress
|
||||
: 0;
|
||||
|
||||
auto alignedBuffer = addressAlignmentBytes > 0
|
||||
? this->readMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedAddressRange.startAddress,
|
||||
addressAlignmentBytes,
|
||||
{}
|
||||
)
|
||||
: TargetMemoryBuffer{};
|
||||
|
||||
alignedBuffer.resize(alignedBufferSize);
|
||||
|
||||
std::copy(
|
||||
buffer.begin(),
|
||||
buffer.begin() + (bufferSize - delegatedBytes),
|
||||
alignedBuffer.begin() + addressAlignmentBytes
|
||||
);
|
||||
|
||||
if (sizeAlignmentBytes > 0) {
|
||||
const auto dataBack = this->readMemory(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
startAddress + bufferSize,
|
||||
sizeAlignmentBytes,
|
||||
{}
|
||||
);
|
||||
std::copy(
|
||||
dataBack.begin(),
|
||||
dataBack.end(),
|
||||
alignedBuffer.begin() + addressAlignmentBytes + bufferSize
|
||||
);
|
||||
}
|
||||
|
||||
this->writeProgramMemoryFullBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
alignedAddressRange.startAddress,
|
||||
alignedBuffer
|
||||
);
|
||||
|
||||
if (delegatedBytes > 0) {
|
||||
// Delegate the final part of the write operation to the partial write method
|
||||
const auto delegatedStartAddress = alignedAddressRange.endAddress + 1;
|
||||
const auto delegatedBuffer = buffer.subspan(bufferSize - delegatedBytes);
|
||||
Logger::debug(
|
||||
"Delegating write operation 0x" + StringService::toHex(delegatedStartAddress) + ", "
|
||||
+ std::to_string(delegatedBuffer.size()) + " byte(s)"
|
||||
);
|
||||
|
||||
this->writeProgramMemoryPartialBlock(
|
||||
addressSpaceDescriptor,
|
||||
memorySegmentDescriptor,
|
||||
delegatedStartAddress,
|
||||
delegatedBuffer
|
||||
);
|
||||
}
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
this->wchLinkInterface.writeFlashFullBlocks(
|
||||
startAddress,
|
||||
buffer,
|
||||
this->programmingBlockSize,
|
||||
this->flashProgramOpcodes
|
||||
);
|
||||
|
||||
/*
|
||||
* Would this not be better placed in endProgrammingSession()? We could persist the command type we invoked to
|
||||
* perform the write, and if required, reattach at the end of the programming session.
|
||||
*
|
||||
* I don't think that would work, because the target needs to be accessible for other operations whilst in
|
||||
* programming mode. We may perform other operations in between program memory writes, but that wouldn't work
|
||||
* if we left the target in an inaccessible state between writes. So I think we have to reattach here.
|
||||
*
|
||||
* TODO: Review after v2.0.0.
|
||||
*/
|
||||
this->deactivate();
|
||||
this->wchLinkInterface.sendCommandAndWaitForResponse(Commands::Control::GetDeviceInfo{});
|
||||
this->activate();
|
||||
}
|
||||
|
||||
bool WchLinkDebugInterface::fullBlockWriteCompatible(
|
||||
const TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
TargetMemoryAddress startAddress
|
||||
) {
|
||||
/*
|
||||
* If we cannot access the entire segment via the full block write method (the segment capacity is not a
|
||||
* multiple of the block size), we delegate the final part of the write operation to the partial write method.
|
||||
*
|
||||
* We use the end address of the final accessible block to determine if the write operation is contained
|
||||
* within the inaccessible region of the segment. If it is, we must not attempt the write operation via the
|
||||
* full block write, as the full block write code doesn't handle instances where the entire operation needs to
|
||||
* be delegated.
|
||||
*
|
||||
* See the WchLinkDebugInterface::writeProgramMemoryFullBlock() member function for more.
|
||||
*/
|
||||
const auto finalBlockEnd = (
|
||||
(memorySegmentDescriptor.addressRange.endAddress / this->programmingBlockSize) * this->programmingBlockSize
|
||||
);
|
||||
return addressSpaceDescriptor == this->sysAddressSpaceDescriptor
|
||||
&& memorySegmentDescriptor.type == TargetMemorySegmentType::FLASH
|
||||
&& memorySegmentDescriptor.size() >= this->programmingBlockSize
|
||||
&& (memorySegmentDescriptor.addressRange.startAddress % this->programmingBlockSize) == 0
|
||||
&& (memorySegmentDescriptor.size() % this->programmingBlockSize == 0 || startAddress <= finalBlockEnd)
|
||||
;
|
||||
}
|
||||
|
||||
std::span<const unsigned char> WchLinkDebugInterface::getFlashProgramOpcodes(const std::string& key) {
|
||||
if (key == "op1") {
|
||||
return FlashProgramOpcodes::FLASH_OP1;
|
||||
|
||||
@@ -112,6 +112,24 @@ namespace DebugToolDrivers::Wch
|
||||
void setSoftwareBreakpoint(const Targets::TargetProgramBreakpoint& breakpoint);
|
||||
void clearSoftwareBreakpoint(const Targets::TargetProgramBreakpoint& breakpoint);
|
||||
|
||||
void writeProgramMemoryPartialBlock(
|
||||
const Targets::TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const Targets::TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
Targets::TargetMemoryAddress startAddress,
|
||||
Targets::TargetMemoryBufferSpan buffer
|
||||
);
|
||||
void writeProgramMemoryFullBlock(
|
||||
const Targets::TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const Targets::TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
Targets::TargetMemoryAddress startAddress,
|
||||
Targets::TargetMemoryBufferSpan buffer
|
||||
);
|
||||
bool fullBlockWriteCompatible(
|
||||
const Targets::TargetAddressSpaceDescriptor& addressSpaceDescriptor,
|
||||
const Targets::TargetMemorySegmentDescriptor& memorySegmentDescriptor,
|
||||
Targets::TargetMemoryAddress startAddress
|
||||
);
|
||||
|
||||
static std::span<const unsigned char> getFlashProgramOpcodes(const std::string& key);
|
||||
};
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user