attn/attn_handler.cpp - openbmc/openpower-hw-diags - Gitiles

 #include <libpdbg.h>

 #include <analyzer/analyzer_main.hpp>
 #include <attn/attention.hpp>
 #include <attn/attn_common.hpp>
 #include <attn/attn_config.hpp>
 #include <attn/attn_dbus.hpp>
 #include <attn/attn_handler.hpp>
 #include <attn/attn_logging.hpp>
 #include <attn/bp_handler.hpp>
 #include <attn/ti_handler.hpp>
 #include <attn/vital_handler.hpp>

 #include <algorithm>
 #include <iomanip>
 #include <map>
 #include <sstream>
 #include <vector>

 namespace attn
 {

 /**
  * @brief Handle checkstop attention
  *
  * @param i_attention Attention object
  * @return 0 indicates that the checkstop attention was successfully handled
  *         1 indicates that the checkstop attention was NOT successfully
  *           handled.
  */
 int handleCheckstop(Attention* i_attention);

 /**
  * @brief Handle special attention
  *
  * @param i_attention Attention object
  * @return 0 indicates that the special attention was successfully handled
  *         1 indicates that the special attention was NOT successfully handled
  */
 int handleSpecial(Attention* i_attention);

 /** @brief Determine if attention is active and not masked */
 bool activeAttn(uint32_t i_val, uint32_t i_mask, uint32_t i_attn);

 /**
  * @brief The main attention handler logic
  *
  * @param i_breakpoints true = breakpoint special attn handling enabled
  */
 void attnHandler(Config* i_config)
 {
     // Vector of active attentions to be handled
     std::vector<Attention> active_attentions;

     uint32_t isr_val, isr_mask;

     // loop through processors looking for active attentions
     trace<level::INFO>("Attention handler started");

     pdbg_target* target;
     pdbg_for_each_class_target("proc", target)
     {
         if (PDBG_TARGET_ENABLED == pdbg_target_probe(target))
         {
             auto proc = pdbg_target_index(target); // get processor number

             // Use PIB target to determine if a processor is enabled
             char path[16];
             sprintf(path, "/proc%d/pib", proc);
             pdbg_target* pibTarget = pdbg_target_from_path(nullptr, path);

             // sanity check
             if (nullptr == pibTarget)
             {
                 trace<level::INFO>("pib path or target not found");
                 continue;
             }

             // check if pib target is enabled
             if (PDBG_TARGET_ENABLED == pdbg_target_probe(pibTarget))
             {
                 // The processor FSI target is required for CFAM read
                 sprintf(path, "/proc%d/fsi", proc);
                 pdbg_target* fsiTarget = pdbg_target_from_path(nullptr, path);

                 // sanity check
                 if (nullptr == fsiTarget)
                 {
                     trace<level::INFO>("fsi path or target not found");
                     continue;
                 }

                 // trace the proc number
                 std::string traceMsg = "proc: " + std::to_string(proc);
                 trace<level::INFO>(traceMsg.c_str());

                 isr_val = 0xffffffff; // invalid isr value

                 // get active attentions on processor
                 if (RC_SUCCESS != fsi_read(fsiTarget, 0x1007, &isr_val))
                 {
                     // log cfam read error
                     trace<level::INFO>("Error! cfam read 0x1007 FAILED");
                     eventAttentionFail((int)AttnSection::attnHandler |
                                        ATTN_PDBG_CFAM);
                 }
                 else if (0xffffffff == isr_val)
                 {
                     trace<level::INFO>("Error! cfam read 0x1007 INVALID");
                     continue;
                 }
                 else
                 {
                     // trace isr value
                     std::stringstream ssIsr;
                     ssIsr << "cfam 0x1007 = 0x" << std::setw(8)
                           << std::setfill('0') << std::hex << isr_val;
                     std::string strobjIsr = ssIsr.str();
                     trace<level::INFO>(strobjIsr.c_str());

                     isr_mask = 0xffffffff; // invalid isr mask

                     // get interrupt enabled special attentions mask
                     if (RC_SUCCESS != fsi_read(fsiTarget, 0x100d, &isr_mask))
                     {
                         // log cfam read error
                         trace<level::INFO>("Error! cfam read 0x100d FAILED");
                         eventAttentionFail((int)AttnSection::attnHandler |
                                            ATTN_PDBG_CFAM);
                     }
                     else if (0xffffffff == isr_mask)
                     {
                         trace<level::INFO>("Error! cfam read 0x100d INVALID");
                         continue;
                     }
                     else
                     {
                         // trace true mask
                         std::stringstream ssMask;
                         ssMask << "cfam 0x100d = 0x" << std::setw(8)
                                << std::setfill('0') << std::hex << isr_mask;
                         std::string strobjMask = ssMask.str();
                         trace<level::INFO>(strobjMask.c_str());

                         // SBE vital attention active and not masked?
                         if (true == activeAttn(isr_val, isr_mask, SBE_ATTN))
                         {
                             active_attentions.emplace_back(Attention::Vital,
                                                            handleVital, target,
                                                            i_config);
                         }

                         // Checkstop attention active and not masked?
                         if (true ==
                             activeAttn(isr_val, isr_mask, CHECKSTOP_ATTN))
                         {
                             active_attentions.emplace_back(Attention::Checkstop,
                                                            handleCheckstop,
                                                            target, i_config);
                         }

                         // Special attention active and not masked?
                         if (true == activeAttn(isr_val, isr_mask, SPECIAL_ATTN))
                         {
                             active_attentions.emplace_back(Attention::Special,
                                                            handleSpecial,
                                                            target, i_config);
                         }
                     } // cfam 0x100d valid
                 }     // cfam 0x1007 valid
             }         // fsi target enabled
         }             // pib target enabled
     }                 // next processor

     // convert to heap, highest priority is at front
     if (!std::is_heap(active_attentions.begin(), active_attentions.end()))
     {
         std::make_heap(active_attentions.begin(), active_attentions.end());
     }

     // call the attention handler until one is handled or all were attempted
     while (false == active_attentions.empty())
     {
         // handle highest priority attention, done if successful
         if (RC_SUCCESS == active_attentions.front().handle())
         {
             // an attention was handled so we are done
             break;
         }

         // move attention to back of vector
         std::pop_heap(active_attentions.begin(), active_attentions.end());

         // remove attention from vector
         active_attentions.pop_back();
     }
 }

 /**
  * @brief Handle checkstop attention
  *
  * @param i_attention Attention object
  * @return 0 indicates that the checkstop attention was successfully handled
  *         1 indicates that the checkstop attention was NOT successfully
  *           handled.
  */
 int handleCheckstop(Attention* i_attention)
 {
     int rc = RC_SUCCESS; // assume checkstop handled

     trace<level::INFO>("checkstop handler started");

     // if checkstop handling enabled, handle checkstop attention
     if (false == (i_attention->getConfig()->getFlag(enCheckstop)))
     {
         trace<level::INFO>("Checkstop handling disabled");
     }
     else
     {
         // Look for any attentions found in hardware. This will generate and
         // commit a PEL if any errors are found.
         if (true != analyzer::analyzeHardware())
         {
             rc = RC_ANALYZER_ERROR;
         }
     }

     return rc;
 }

 /**
  * @brief Handle special attention
  *
  * @param i_attention Attention object
  * @return 0 indicates that the special attention was successfully handled
  *         1 indicates that the special attention was NOT successfully handled
  */
 int handleSpecial(Attention* i_attention)
 {
     int rc = RC_SUCCESS; // assume special attention handled

     // The TI info chipop will give us a pointer to the TI info data
     uint8_t* tiInfo       = nullptr;                  // ptr to TI info data
     uint32_t tiInfoLen    = 0;                        // length of TI info data
     pdbg_target* attnProc = i_attention->getTarget(); // proc with attention

     bool tiInfoStatic = false; // assume TI info was provided (not created)

     if (attnProc != nullptr)
     {
         // The processor PIB target is required for get TI info chipop
         char path[16];
         sprintf(path, "/proc%d/pib", pdbg_target_index(attnProc));
         pdbg_target* tiInfoTarget = pdbg_target_from_path(nullptr, path);

         if (nullptr != tiInfoTarget)
         {
             if (PDBG_TARGET_ENABLED == pdbg_target_probe(tiInfoTarget))
             {
                 sbe_mpipl_get_ti_info(tiInfoTarget, &tiInfo, &tiInfoLen);

                 // If TI info not available use default based on host state
                 if (nullptr == tiInfo)
                 {
                     trace<level::INFO>("TI info data ptr is invalid");

                     HostRunningState runningState = hostRunningState();
                     std::string stateString       = "host state unknown";

                     if ((HostRunningState::Started == runningState) ||
                         (HostRunningState::Unknown == runningState))
                     {
                         if (HostRunningState::Started == runningState)
                         {
                             stateString = "host started";
                         }
                         tiInfo = (uint8_t*)defaultPhypTiInfo;
                     }
                     else
                     {
                         stateString = "host not started";
                         tiInfo      = (uint8_t*)defaultHbTiInfo;
                     }

                     // trace host state
                     trace<level::INFO>(stateString.c_str());

                     tiInfoStatic = true; // using our TI info
                 }
             }
         }
     }

     bool tiInfoValid = false; // TI area data not valid or not available

     // If TI area exists and is marked valid we can assume TI occurred
     if ((nullptr != tiInfo) && (0 != tiInfo[0]))
     {
         TiDataArea* tiDataArea = (TiDataArea*)tiInfo;

         std::stringstream ss; // string stream object for tracing
         std::string strobj;   // string object for tracing

         // trace a few known TI data area values
         ss.str(std::string()); // empty the stream
         ss.clear();            // clear the stream
         ss << "TI data command = 0x" << std::setw(2) << std::setfill('0')
            << std::hex << (int)tiDataArea->command;
         strobj = ss.str();
         trace<level::INFO>(strobj.c_str());

         // Another check for valid TI Info since it has been seen that
         // tiInfo[0] != 0 but TI info is not valid
         if (0xa1 == tiDataArea->command)
         {
             tiInfoValid = true;

             // trace some more data since TI info appears valid
             ss.str(std::string()); // empty the stream
             ss.clear();            // clear the stream
             ss << "TI data term-type = 0x" << std::setw(2) << std::setfill('0')
                << std::hex << (int)tiDataArea->hbTerminateType;
             strobj = ss.str();
             trace<level::INFO>(strobj.c_str());

             ss.str(std::string()); // empty the stream
             ss.clear();            // clear the stream
             ss << "TI data SRC format = 0x" << std::setw(2) << std::setfill('0')
                << std::hex << (int)tiDataArea->srcFormat;
             strobj = ss.str();
             trace<level::INFO>(strobj.c_str());

             ss.str(std::string()); // empty the stream
             ss.clear();            // clear the stream
             ss << "TI data source = 0x" << std::setw(2) << std::setfill('0')
                << std::hex << (int)tiDataArea->source;
             strobj = ss.str();
             trace<level::INFO>(strobj.c_str());

             if (true == (i_attention->getConfig()->getFlag(enTerminate)))
             {
                 // Call TI special attention handler
                 rc = tiHandler(tiDataArea);
             }
         }
     }

     // If TI area not valid or not available
     if (false == tiInfoValid)
     {
         trace<level::INFO>("TI info NOT available");

         // if configured to handle breakpoint as default special attention
         if (i_attention->getConfig()->getFlag(dfltBreakpoint))
         {
             if (true == (i_attention->getConfig()->getFlag(enBreakpoints)))
             {
                 // Call the breakpoint special attention handler
                 bpHandler();
             }
         }
         // if configured to handle TI as default special attention
         else
         {
             if (true == (i_attention->getConfig()->getFlag(enTerminate)))
             {
                 // Call TI special attention handler
                 rc = tiHandler(nullptr);
             }
         }
     }

     // release TI data buffer
     if ((nullptr != tiInfo) && (false == tiInfoStatic))
     {
         free(tiInfo);
     }

     if (RC_SUCCESS != rc)
     {
         trace<level::INFO>("Special attn not handled");
     }

     return rc;
 }

 /**
  * @brief Determine if attention is active and not masked
  *
  * Determine whether an attention needs to be handled and trace details of
  * attention type and whether it is masked or not.
  *
  * @param i_val attention status register
  * @param i_mask attention true mask register
  * @param i_attn attention type
  * @param i_proc processor associated with registers
  *
  * @return true if attention is active and not masked, otherwise false
  */
 bool activeAttn(uint32_t i_val, uint32_t i_mask, uint32_t i_attn)
 {
     bool rc = false; // assume attn masked and/or inactive

     // if attention active
     if (0 != (i_val & i_attn))
     {
         std::stringstream ss;

         bool validAttn = true; // known attention type

         switch (i_attn)
         {
             case SBE_ATTN:
                 ss << "SBE attn";
                 break;
             case CHECKSTOP_ATTN:
                 ss << "Checkstop attn";
                 break;
             case SPECIAL_ATTN:
                 ss << "Special attn";
                 break;
             default:
                 ss << "Unknown attn";
                 validAttn = false;
         }

         // see if attention is masked
         if (true == validAttn)
         {
             if (0 != (i_mask & i_attn))
             {
                 rc = true; // attention active and not masked
             }
             else
             {
                 ss << " masked";
             }
         }

         std::string strobj = ss.str();      // ss.str() is temporary
         trace<level::INFO>(strobj.c_str()); // commit trace stream
     }

     return rc;
 }

 } // namespace attn
	#include <libpdbg.h>

	#include <analyzer/analyzer_main.hpp>
	#include <attn/attention.hpp>
	#include <attn/attn_common.hpp>
	#include <attn/attn_config.hpp>
	#include <attn/attn_dbus.hpp>
	#include <attn/attn_handler.hpp>
	#include <attn/attn_logging.hpp>
	#include <attn/bp_handler.hpp>
	#include <attn/ti_handler.hpp>
	#include <attn/vital_handler.hpp>

	#include <algorithm>
	#include <iomanip>
	#include <map>
	#include <sstream>
	#include <vector>

	namespace attn
	{

	/**
	* @brief Handle checkstop attention
	*
	* @param i_attention Attention object
	* @return 0 indicates that the checkstop attention was successfully handled
	* 1 indicates that the checkstop attention was NOT successfully
	* handled.
	*/
	int handleCheckstop(Attention* i_attention);

	/**
	* @brief Handle special attention
	*
	* @param i_attention Attention object
	* @return 0 indicates that the special attention was successfully handled
	* 1 indicates that the special attention was NOT successfully handled
	*/
	int handleSpecial(Attention* i_attention);

	/** @brief Determine if attention is active and not masked */
	bool activeAttn(uint32_t i_val, uint32_t i_mask, uint32_t i_attn);

	/**
	* @brief The main attention handler logic
	*
	* @param i_breakpoints true = breakpoint special attn handling enabled
	*/
	void attnHandler(Config* i_config)
	{
	// Vector of active attentions to be handled
	std::vector<Attention> active_attentions;

	uint32_t isr_val, isr_mask;

	// loop through processors looking for active attentions
	trace<level::INFO>("Attention handler started");

	pdbg_target* target;
	pdbg_for_each_class_target("proc", target)
	{
	if (PDBG_TARGET_ENABLED == pdbg_target_probe(target))
	{
	auto proc = pdbg_target_index(target); // get processor number

	// Use PIB target to determine if a processor is enabled
	char path[16];
	sprintf(path, "/proc%d/pib", proc);
	pdbg_target* pibTarget = pdbg_target_from_path(nullptr, path);

	// sanity check
	if (nullptr == pibTarget)
	{
	trace<level::INFO>("pib path or target not found");
	continue;
	}

	// check if pib target is enabled
	if (PDBG_TARGET_ENABLED == pdbg_target_probe(pibTarget))
	{
	// The processor FSI target is required for CFAM read
	sprintf(path, "/proc%d/fsi", proc);
	pdbg_target* fsiTarget = pdbg_target_from_path(nullptr, path);

	// sanity check
	if (nullptr == fsiTarget)
	{
	trace<level::INFO>("fsi path or target not found");
	continue;
	}

	// trace the proc number
	std::string traceMsg = "proc: " + std::to_string(proc);
	trace<level::INFO>(traceMsg.c_str());

	isr_val = 0xffffffff; // invalid isr value

	// get active attentions on processor
	if (RC_SUCCESS != fsi_read(fsiTarget, 0x1007, &isr_val))
	{
	// log cfam read error
	trace<level::INFO>("Error! cfam read 0x1007 FAILED");
	eventAttentionFail((int)AttnSection::attnHandler \|
	ATTN_PDBG_CFAM);
	}
	else if (0xffffffff == isr_val)
	{
	trace<level::INFO>("Error! cfam read 0x1007 INVALID");
	continue;
	}
	else
	{
	// trace isr value
	std::stringstream ssIsr;
	ssIsr << "cfam 0x1007 = 0x" << std::setw(8)
	<< std::setfill('0') << std::hex << isr_val;
	std::string strobjIsr = ssIsr.str();
	trace<level::INFO>(strobjIsr.c_str());

	isr_mask = 0xffffffff; // invalid isr mask

	// get interrupt enabled special attentions mask
	if (RC_SUCCESS != fsi_read(fsiTarget, 0x100d, &isr_mask))
	{
	// log cfam read error
	trace<level::INFO>("Error! cfam read 0x100d FAILED");
	eventAttentionFail((int)AttnSection::attnHandler \|
	ATTN_PDBG_CFAM);
	}
	else if (0xffffffff == isr_mask)
	{
	trace<level::INFO>("Error! cfam read 0x100d INVALID");
	continue;
	}
	else
	{
	// trace true mask
	std::stringstream ssMask;
	ssMask << "cfam 0x100d = 0x" << std::setw(8)
	<< std::setfill('0') << std::hex << isr_mask;
	std::string strobjMask = ssMask.str();
	trace<level::INFO>(strobjMask.c_str());

	// SBE vital attention active and not masked?
	if (true == activeAttn(isr_val, isr_mask, SBE_ATTN))
	{
	active_attentions.emplace_back(Attention::Vital,
	handleVital, target,
	i_config);
	}

	// Checkstop attention active and not masked?
	if (true ==
	activeAttn(isr_val, isr_mask, CHECKSTOP_ATTN))
	{
	active_attentions.emplace_back(Attention::Checkstop,
	handleCheckstop,
	target, i_config);
	}

	// Special attention active and not masked?
	if (true == activeAttn(isr_val, isr_mask, SPECIAL_ATTN))
	{
	active_attentions.emplace_back(Attention::Special,
	handleSpecial,
	target, i_config);
	}
	} // cfam 0x100d valid
	} // cfam 0x1007 valid
	} // fsi target enabled
	} // pib target enabled
	} // next processor

	// convert to heap, highest priority is at front
	if (!std::is_heap(active_attentions.begin(), active_attentions.end()))
	{
	std::make_heap(active_attentions.begin(), active_attentions.end());
	}

	// call the attention handler until one is handled or all were attempted
	while (false == active_attentions.empty())
	{
	// handle highest priority attention, done if successful
	if (RC_SUCCESS == active_attentions.front().handle())
	{
	// an attention was handled so we are done
	break;
	}

	// move attention to back of vector
	std::pop_heap(active_attentions.begin(), active_attentions.end());

	// remove attention from vector
	active_attentions.pop_back();
	}
	}

	/**
	* @brief Handle checkstop attention
	*
	* @param i_attention Attention object
	* @return 0 indicates that the checkstop attention was successfully handled
	* 1 indicates that the checkstop attention was NOT successfully
	* handled.
	*/
	int handleCheckstop(Attention* i_attention)
	{
	int rc = RC_SUCCESS; // assume checkstop handled

	trace<level::INFO>("checkstop handler started");

	// if checkstop handling enabled, handle checkstop attention
	if (false == (i_attention->getConfig()->getFlag(enCheckstop)))
	{
	trace<level::INFO>("Checkstop handling disabled");
	}
	else
	{
	// Look for any attentions found in hardware. This will generate and
	// commit a PEL if any errors are found.
	if (true != analyzer::analyzeHardware())
	{
	rc = RC_ANALYZER_ERROR;
	}
	}

	return rc;
	}

	/**
	* @brief Handle special attention
	*
	* @param i_attention Attention object
	* @return 0 indicates that the special attention was successfully handled
	* 1 indicates that the special attention was NOT successfully handled
	*/
	int handleSpecial(Attention* i_attention)
	{
	int rc = RC_SUCCESS; // assume special attention handled

	// The TI info chipop will give us a pointer to the TI info data
	uint8_t* tiInfo = nullptr; // ptr to TI info data
	uint32_t tiInfoLen = 0; // length of TI info data
	pdbg_target* attnProc = i_attention->getTarget(); // proc with attention

	bool tiInfoStatic = false; // assume TI info was provided (not created)

	if (attnProc != nullptr)
	{
	// The processor PIB target is required for get TI info chipop
	char path[16];
	sprintf(path, "/proc%d/pib", pdbg_target_index(attnProc));
	pdbg_target* tiInfoTarget = pdbg_target_from_path(nullptr, path);

	if (nullptr != tiInfoTarget)
	{
	if (PDBG_TARGET_ENABLED == pdbg_target_probe(tiInfoTarget))
	{
	sbe_mpipl_get_ti_info(tiInfoTarget, &tiInfo, &tiInfoLen);

	// If TI info not available use default based on host state
	if (nullptr == tiInfo)
	{
	trace<level::INFO>("TI info data ptr is invalid");

	HostRunningState runningState = hostRunningState();
	std::string stateString = "host state unknown";

	if ((HostRunningState::Started == runningState) \|\|
	(HostRunningState::Unknown == runningState))
	{
	if (HostRunningState::Started == runningState)
	{
	stateString = "host started";
	}
	tiInfo = (uint8_t*)defaultPhypTiInfo;
	}
	else
	{
	stateString = "host not started";
	tiInfo = (uint8_t*)defaultHbTiInfo;
	}

	// trace host state
	trace<level::INFO>(stateString.c_str());

	tiInfoStatic = true; // using our TI info
	}
	}
	}
	}

	bool tiInfoValid = false; // TI area data not valid or not available

	// If TI area exists and is marked valid we can assume TI occurred
	if ((nullptr != tiInfo) && (0 != tiInfo[0]))
	{
	TiDataArea* tiDataArea = (TiDataArea*)tiInfo;

	std::stringstream ss; // string stream object for tracing
	std::string strobj; // string object for tracing

	// trace a few known TI data area values
	ss.str(std::string()); // empty the stream
	ss.clear(); // clear the stream
	ss << "TI data command = 0x" << std::setw(2) << std::setfill('0')
	<< std::hex << (int)tiDataArea->command;
	strobj = ss.str();
	trace<level::INFO>(strobj.c_str());

	// Another check for valid TI Info since it has been seen that
	// tiInfo[0] != 0 but TI info is not valid
	if (0xa1 == tiDataArea->command)
	{
	tiInfoValid = true;

	// trace some more data since TI info appears valid
	ss.str(std::string()); // empty the stream
	ss.clear(); // clear the stream
	ss << "TI data term-type = 0x" << std::setw(2) << std::setfill('0')
	<< std::hex << (int)tiDataArea->hbTerminateType;
	strobj = ss.str();
	trace<level::INFO>(strobj.c_str());

	ss.str(std::string()); // empty the stream
	ss.clear(); // clear the stream
	ss << "TI data SRC format = 0x" << std::setw(2) << std::setfill('0')
	<< std::hex << (int)tiDataArea->srcFormat;
	strobj = ss.str();
	trace<level::INFO>(strobj.c_str());

	ss.str(std::string()); // empty the stream
	ss.clear(); // clear the stream
	ss << "TI data source = 0x" << std::setw(2) << std::setfill('0')
	<< std::hex << (int)tiDataArea->source;
	strobj = ss.str();
	trace<level::INFO>(strobj.c_str());

	if (true == (i_attention->getConfig()->getFlag(enTerminate)))
	{
	// Call TI special attention handler
	rc = tiHandler(tiDataArea);
	}
	}
	}

	// If TI area not valid or not available
	if (false == tiInfoValid)
	{
	trace<level::INFO>("TI info NOT available");

	// if configured to handle breakpoint as default special attention
	if (i_attention->getConfig()->getFlag(dfltBreakpoint))
	{
	if (true == (i_attention->getConfig()->getFlag(enBreakpoints)))
	{
	// Call the breakpoint special attention handler
	bpHandler();
	}
	}
	// if configured to handle TI as default special attention
	else
	{
	if (true == (i_attention->getConfig()->getFlag(enTerminate)))
	{
	// Call TI special attention handler
	rc = tiHandler(nullptr);
	}
	}
	}

	// release TI data buffer
	if ((nullptr != tiInfo) && (false == tiInfoStatic))
	{
	free(tiInfo);
	}

	if (RC_SUCCESS != rc)
	{
	trace<level::INFO>("Special attn not handled");
	}

	return rc;
	}

	/**
	* @brief Determine if attention is active and not masked
	*
	* Determine whether an attention needs to be handled and trace details of
	* attention type and whether it is masked or not.
	*
	* @param i_val attention status register
	* @param i_mask attention true mask register
	* @param i_attn attention type
	* @param i_proc processor associated with registers
	*
	* @return true if attention is active and not masked, otherwise false
	*/
	bool activeAttn(uint32_t i_val, uint32_t i_mask, uint32_t i_attn)
	{
	bool rc = false; // assume attn masked and/or inactive

	// if attention active
	if (0 != (i_val & i_attn))
	{
	std::stringstream ss;

	bool validAttn = true; // known attention type

	switch (i_attn)
	{
	case SBE_ATTN:
	ss << "SBE attn";
	break;
	case CHECKSTOP_ATTN:
	ss << "Checkstop attn";
	break;
	case SPECIAL_ATTN:
	ss << "Special attn";
	break;
	default:
	ss << "Unknown attn";
	validAttn = false;
	}

	// see if attention is masked
	if (true == validAttn)
	{
	if (0 != (i_mask & i_attn))
	{
	rc = true; // attention active and not masked
	}
	else
	{
	ss << " masked";
	}
	}

	std::string strobj = ss.str(); // ss.str() is temporary
	trace<level::INFO>(strobj.c_str()); // commit trace stream
	}

	return rc;
	}

	} // namespace attn