src/isolator/hei_isolation_node.cpp - openbmc/openpower-libhei - Gitiles

 #include <isolator/hei_isolation_node.hpp>
 #include <util/hei_bit_string.hpp>

 namespace libhei
 {

 //------------------------------------------------------------------------------

 bool IsolationNode::analyze(const Chip& i_chip, AttentionType_t i_attnType,
                             IsolationData& io_isoData) const
 {
     bool o_activeAttn = false; // Initially, assume no active attentions.

     // Keep track of nodes that have been analyzed to avoid cyclic isolation.
     pushIsolationStack();

     // Capture default set of registers for this node.
     captureRegisters(i_chip, io_isoData);

     // Get the rule for this attention type.
     auto rule_itr = iv_rules.find(i_attnType);

     // It is possible that a rule does not exist. The likely scenario is that
     // this node is intended to only gather FFDC for a specific bit in the
     // parent node.
     if (iv_rules.end() != rule_itr)
     {
         // Get the returned BitString for this rule.
         const BitString* bs = rule_itr->second->getBitString(i_chip);

         // Ensure this BitString is not longer than the maximum bit field.
         HEI_ASSERT(bs->getBitLen() <= (1 << (sizeof(BitPosition_t) * 8)));

         // Find all active bits for this rule.
         for (BitPosition_t bit = 0; bit < bs->getBitLen(); bit++)
         {
             // Continue to the next bit if not active.
             if (!bs->isBitSet(bit))
                 continue;

             // At least one active bit was found.
             o_activeAttn = true;

             // Capture registers specific to this isolation bit.
             captureRegisters(i_chip, io_isoData, bit);

             // Determine if this attention originated from another register or
             // if it is a leaf in the isolation tree.
             auto child_itr = iv_children.find(bit);
             if (iv_children.end() != child_itr)
             {
                 // This bit was driven from an attention from another register.
                 // Continue down the isolation tree to look for more attentions.
                 bool attnFound = child_itr->second->analyze(i_chip, i_attnType,
                                                             io_isoData);
                 if (!attnFound)
                 {
                     // It is possible the child node is only intended for FFDC.
                     // See comment near the check for a valid rule above.
                     // Otherwise, it is possible something went wrong. If there
                     // should have been an active attention, it's possible there
                     // is a bug in the Chip Data File. Or, it is also possible
                     // some other piece of code is clearing the attention before
                     // this code is able to analyze it. Another possibility is
                     // that the hardware it not behaving as expected. Since we
                     // really don't know what happened, we should not assert.
                     // Instead, add this bit's signature to io_isoData. If there
                     // are no other active attentions, the user application
                     // could use this signature to help determine, and
                     // circumvent, the isolation problem.
                     io_isoData.addSignature(
                         Signature{i_chip, iv_id, iv_instance, bit, i_attnType});
                 }
             }
             else
             {
                 // We have reached a leaf in the isolation tree. Add this bit's
                 // signature to io_isoData.
                 io_isoData.addSignature(
                     Signature{i_chip, iv_id, iv_instance, bit, i_attnType});
             }
         }
     }

     // Analysis is complete on this node. So remove it from cv_isolationStack.
     popIsolationStack();

     return o_activeAttn;
 }

 //------------------------------------------------------------------------------

 void IsolationNode::addCaptureRegister(HardwareRegister::ConstPtr i_hwReg,
                                        BitPosition_t i_bit)
 {
     HEI_ASSERT(i_hwReg); // should not be null

     // Check the bit range.
     if (MAX_BIT_POSITION != i_bit)
     {
         if (REG_TYPE_SCOM == iv_regType || REG_TYPE_ID_SCOM == iv_regType)
         {
             HEI_ASSERT(i_bit < 64);
         }
         else
         {
             HEI_ASSERT(false); // register type unsupported
         }
     }

     // Add this capture register only if it does not already exist in the list.
     auto itr = iv_capRegs.find(i_bit);
     if (iv_capRegs.end() == itr ||
         itr->second.end() ==
             std::find(itr->second.begin(), itr->second.end(), i_hwReg))
     {
         iv_capRegs[i_bit].push_back(i_hwReg);
     }
 }

 //------------------------------------------------------------------------------

 void IsolationNode::addRule(AttentionType_t i_attnType,
                             Register::ConstPtr i_rule)
 {
     HEI_ASSERT(i_rule); // should not be null

     auto ret = iv_rules.emplace(i_attnType, i_rule);

     // If an entry already existed, it must point to the same object.
     HEI_ASSERT(ret.second || (ret.first->second == i_rule));
 }

 //------------------------------------------------------------------------------

 void IsolationNode::addChild(uint8_t i_bit, ConstPtr i_child)
 {
     HEI_ASSERT(i_child); // should not be null

     auto ret = iv_children.emplace(i_bit, i_child);

     // If an entry already existed, it must point to the same object.
     HEI_ASSERT(ret.second || (ret.first->second == i_child));
 }

 //------------------------------------------------------------------------------

 std::vector<const IsolationNode*> IsolationNode::cv_isolationStack{};

 //------------------------------------------------------------------------------

 void IsolationNode::pushIsolationStack() const
 {
     // Ensure this node does not already exist in cv_isolationStack.
     auto itr = std::find(cv_isolationStack.begin(), cv_isolationStack.end(),
                          this);
     HEI_ASSERT(cv_isolationStack.end() == itr);

     // Push to node to the stack.
     cv_isolationStack.push_back(this);
 }

 //------------------------------------------------------------------------------

 void IsolationNode::captureRegisters(const Chip& i_chip,
                                      IsolationData& io_isoData,
                                      BitPosition_t i_bit) const
 {
     auto itr = iv_capRegs.find(i_bit);
     if (iv_capRegs.end() != itr)
     {
         // Capture all registers for this node.
         for (const auto& hwReg : itr->second)
         {
             // Read the register (adds BitString to register cache).
             if (hwReg->read(i_chip))
             {
                 // The register read failed.
                 // TODO: Would be nice to add SCOM errors to the log just in
                 // case
                 //       traces are not available.
                 // TODO: This trace could be redundant with the user
                 // application,
                 //       which will have more information on the actual chip
                 //       that failed anyway. Leaving it commented out for now
                 //       until the SCOM errors are added to the log.
                 // HEI_ERR("register read failed on chip type=0x%0" PRIx32
                 //         "address=0x%0" PRIx64,
                 //         i_chip.getType(), hwReg->getAddress());
             }
             else
             {
                 // Add to the FFDC.
                 io_isoData.addRegister(i_chip, hwReg->getId(),
                                        hwReg->getInstance(),
                                        hwReg->getBitString(i_chip));
             }
         }
     }
 }

 //------------------------------------------------------------------------------

 } // end namespace libhei
	#include <isolator/hei_isolation_node.hpp>
	#include <util/hei_bit_string.hpp>

	namespace libhei
	{

	//------------------------------------------------------------------------------

	bool IsolationNode::analyze(const Chip& i_chip, AttentionType_t i_attnType,
	IsolationData& io_isoData) const
	{
	bool o_activeAttn = false; // Initially, assume no active attentions.

	// Keep track of nodes that have been analyzed to avoid cyclic isolation.
	pushIsolationStack();

	// Capture default set of registers for this node.
	captureRegisters(i_chip, io_isoData);

	// Get the rule for this attention type.
	auto rule_itr = iv_rules.find(i_attnType);

	// It is possible that a rule does not exist. The likely scenario is that
	// this node is intended to only gather FFDC for a specific bit in the
	// parent node.
	if (iv_rules.end() != rule_itr)
	{
	// Get the returned BitString for this rule.
	const BitString* bs = rule_itr->second->getBitString(i_chip);

	// Ensure this BitString is not longer than the maximum bit field.
	HEI_ASSERT(bs->getBitLen() <= (1 << (sizeof(BitPosition_t) * 8)));

	// Find all active bits for this rule.
	for (BitPosition_t bit = 0; bit < bs->getBitLen(); bit++)
	{
	// Continue to the next bit if not active.
	if (!bs->isBitSet(bit))
	continue;

	// At least one active bit was found.
	o_activeAttn = true;

	// Capture registers specific to this isolation bit.
	captureRegisters(i_chip, io_isoData, bit);

	// Determine if this attention originated from another register or
	// if it is a leaf in the isolation tree.
	auto child_itr = iv_children.find(bit);
	if (iv_children.end() != child_itr)
	{
	// This bit was driven from an attention from another register.
	// Continue down the isolation tree to look for more attentions.
	bool attnFound = child_itr->second->analyze(i_chip, i_attnType,
	io_isoData);
	if (!attnFound)
	{
	// It is possible the child node is only intended for FFDC.
	// See comment near the check for a valid rule above.
	// Otherwise, it is possible something went wrong. If there
	// should have been an active attention, it's possible there
	// is a bug in the Chip Data File. Or, it is also possible
	// some other piece of code is clearing the attention before
	// this code is able to analyze it. Another possibility is
	// that the hardware it not behaving as expected. Since we
	// really don't know what happened, we should not assert.
	// Instead, add this bit's signature to io_isoData. If there
	// are no other active attentions, the user application
	// could use this signature to help determine, and
	// circumvent, the isolation problem.
	io_isoData.addSignature(
	Signature{i_chip, iv_id, iv_instance, bit, i_attnType});
	}
	}
	else
	{
	// We have reached a leaf in the isolation tree. Add this bit's
	// signature to io_isoData.
	io_isoData.addSignature(
	Signature{i_chip, iv_id, iv_instance, bit, i_attnType});
	}
	}
	}

	// Analysis is complete on this node. So remove it from cv_isolationStack.
	popIsolationStack();

	return o_activeAttn;
	}

	//------------------------------------------------------------------------------

	void IsolationNode::addCaptureRegister(HardwareRegister::ConstPtr i_hwReg,
	BitPosition_t i_bit)
	{
	HEI_ASSERT(i_hwReg); // should not be null

	// Check the bit range.
	if (MAX_BIT_POSITION != i_bit)
	{
	if (REG_TYPE_SCOM == iv_regType \|\| REG_TYPE_ID_SCOM == iv_regType)
	{
	HEI_ASSERT(i_bit < 64);
	}
	else
	{
	HEI_ASSERT(false); // register type unsupported
	}
	}

	// Add this capture register only if it does not already exist in the list.
	auto itr = iv_capRegs.find(i_bit);
	if (iv_capRegs.end() == itr \|\|
	itr->second.end() ==
	std::find(itr->second.begin(), itr->second.end(), i_hwReg))
	{
	iv_capRegs[i_bit].push_back(i_hwReg);
	}
	}

	//------------------------------------------------------------------------------

	void IsolationNode::addRule(AttentionType_t i_attnType,
	Register::ConstPtr i_rule)
	{
	HEI_ASSERT(i_rule); // should not be null

	auto ret = iv_rules.emplace(i_attnType, i_rule);

	// If an entry already existed, it must point to the same object.
	HEI_ASSERT(ret.second \|\| (ret.first->second == i_rule));
	}

	//------------------------------------------------------------------------------

	void IsolationNode::addChild(uint8_t i_bit, ConstPtr i_child)
	{
	HEI_ASSERT(i_child); // should not be null

	auto ret = iv_children.emplace(i_bit, i_child);

	// If an entry already existed, it must point to the same object.
	HEI_ASSERT(ret.second \|\| (ret.first->second == i_child));
	}

	//------------------------------------------------------------------------------

	std::vector<const IsolationNode*> IsolationNode::cv_isolationStack{};

	//------------------------------------------------------------------------------

	void IsolationNode::pushIsolationStack() const
	{
	// Ensure this node does not already exist in cv_isolationStack.
	auto itr = std::find(cv_isolationStack.begin(), cv_isolationStack.end(),
	this);
	HEI_ASSERT(cv_isolationStack.end() == itr);

	// Push to node to the stack.
	cv_isolationStack.push_back(this);
	}

	//------------------------------------------------------------------------------

	void IsolationNode::captureRegisters(const Chip& i_chip,
	IsolationData& io_isoData,
	BitPosition_t i_bit) const
	{
	auto itr = iv_capRegs.find(i_bit);
	if (iv_capRegs.end() != itr)
	{
	// Capture all registers for this node.
	for (const auto& hwReg : itr->second)
	{
	// Read the register (adds BitString to register cache).
	if (hwReg->read(i_chip))
	{
	// The register read failed.
	// TODO: Would be nice to add SCOM errors to the log just in
	// case
	// traces are not available.
	// TODO: This trace could be redundant with the user
	// application,
	// which will have more information on the actual chip
	// that failed anyway. Leaving it commented out for now
	// until the SCOM errors are added to the log.
	// HEI_ERR("register read failed on chip type=0x%0" PRIx32
	// "address=0x%0" PRIx64,
	// i_chip.getType(), hwReg->getAddress());
	}
	else
	{
	// Add to the FFDC.
	io_isoData.addRegister(i_chip, hwReg->getId(),
	hwReg->getInstance(),
	hwReg->getBitString(i_chip));
	}
	}
	}
	}

	//------------------------------------------------------------------------------

	} // end namespace libhei