X-Git-Url: http://git.rot13.org//?p=goodfet;a=blobdiff_plain;f=firmware%2Fapps%2Fjtag%2Fjtag.c;fp=firmware%2Fapps%2Fjtag%2Fjtag.c;h=b813d5d0ea7c990014723c42ed2ab16cbfe8ff9f;hp=bda0fac41a8756a4fe2eb614ba67a9be2aea8b4b;hb=cfbda5b069e5c792b4b3a91911c3fc9844b68fbc;hpb=27b44f95b9b34cfd2e8e99106bc55428630e844a

diff --git a/firmware/apps/jtag/jtag.c b/firmware/apps/jtag/jtag.c
index bda0fac..b813d5d 100644
--- a/firmware/apps/jtag/jtag.c
+++ b/firmware/apps/jtag/jtag.c
@@ -38,292 +38,511 @@ app_t const jtag_app = {
 };
 
 
+//! Remembers what the current JTAG state is
+enum eTAPState jtag_state = UNKNOWN;
+
+//! Returns true if we're in any of the data register states
+int in_dr()
+{
+	return (int)(jtag_state & (SELECT_DR_SCAN | CAPTURE_DR |
+							   SHIFT_DR | EXIT1_DR | PAUSE_DR |
+							   EXIT2_DR | UPDATE_DR));
+}
+
+//! Returns true if we're in any of the instruction register states
+int in_ir()
+{
+	return (int)(jtag_state & (SELECT_IR_SCAN | CAPTURE_IR |
+							   SHIFT_IR | EXIT1_IR | PAUSE_IR |
+							   EXIT2_IR | UPDATE_IR));
+}
+
+//! Returns true if we're in run-test-idle state
+int in_run_test_idle()
+{
+	return (int)(jtag_state & RUN_TEST_IDLE);
+}
+
+//! Check the state
+int in_state(enum eTAPState state)
+{
+	return (int)(jtag_state & state);
+}
+
+
+//! Reset the target device
+void jtag_reset_target()
+{
+	SETRST;
+	PLEDOUT^=PLEDPIN; 
+	CLRRST;
+	PLEDOUT^=PLEDPIN; 
+}
+
+//! Clock the JTAG clock line
+void jtag_tcktock() 
+{
+	CLRTCK; 
+	PLEDOUT^=PLEDPIN; 
+	SETTCK; 
+	PLEDOUT^=PLEDPIN;
+}
+
+//! Goes through test-logic-reset and ends in run-test-idle
+void jtag_reset_tap()
+{
+	CLRMOSI;
+	SETTMS;
+	jtag_tcktock();
+	jtag_tcktock();
+	jtag_tcktock();
+	jtag_tcktock();
+	jtag_tcktock();  // now in Reset state
+	CLRTMS;
+	jtag_tcktock();  // now in Run-Test/Idle state
+	jtag_state = RUN_TEST_IDLE;
+}
+
 //! Set up the pins for JTAG mode.
-void jtagsetup(){
-  P5DIR|=MOSI+SCK+TMS;
-  P5DIR&=~MISO;
-  /*
-  P5OUT|=0xFFFF;
-  P5OUT=0;
-  */
-  P4DIR|=TST;
-  P2DIR|=RST;
-  msdelay(100);
+void jtag_setup()
+{
+	P5DIR|=MOSI+SCK+TMS;
+	P5DIR&=~MISO;
+	P4DIR|=TST;
+	P2DIR|=RST;
+	msdelay(100);
+	jtag_state = UNKNOWN;
 }
 
-/************************** JTAG Primitives ****************************/
-// these have been turned into functions to save flash space
-void jtag_tcktock() {
-  CLRTCK; 
-  PLEDOUT^=PLEDPIN; 
-  SETTCK; 
-  PLEDOUT^=PLEDPIN;
+//! Stop JTAG, release pins
+void jtag_stop()
+{
+	P5OUT=0;
+	P4OUT=0;
 }
 
-void jtag_goto_shift_ir() {
-  SETTMS;
-  jtag_tcktock();
-  jtag_tcktock();
-  CLRTMS;
-  jtag_tcktock();
-  jtag_tcktock();
+//! Get into Shift-IR or Shift-DR state
+void jtag_shift_register()
+{
+	// assumes we're in any state that can transition to Shift-IR or Shift-DR
+	if (!in_state(CAPTURE_DR | CAPTURE_IR | SHIFT_DR | 
+				  SHIFT_IR | EXIT2_DR | EXIT2_IR ))
+	{
+		debugstr("Invalid JTAG state");
+		return;
+	}
+
+	CLRMOSI;
+	CLRTMS;
+	jtag_tcktock();
 
+	if (in_dr())
+		jtag_state = SHIFT_DR;
+	else
+		jtag_state = SHIFT_IR;
 }
-void jtag_goto_shift_dr() {
-  SETTMS;
-  jtag_tcktock();
-  CLRTMS;
-  jtag_tcktock();
-  jtag_tcktock();
+
+//! Get into Capture-IR state
+void jtag_capture_ir()
+{
+	// assumes you're in Run-Test/Idle, Update-DR or Update-IR
+	if (!in_state(RUN_TEST_IDLE | UPDATE_DR | UPDATE_IR))
+	{
+		debugstr("Invalid JTAG state");
+		return;
+	}
+
+	CLRMOSI;
+	SETTMS;
+	jtag_tcktock(); // Select-DR-Scan
+	jtag_tcktock(); // Select-IR-Scan
+	CLRTMS;
+	jtag_tcktock(); // Capture-IR
+
+	jtag_state = CAPTURE_IR;
 }
 
-void jtag_resettap(){
-  SETTMS;
-  jtag_tcktock();
-  jtag_tcktock();
-  jtag_tcktock();
-  jtag_tcktock();
-  jtag_tcktock();  // now in Reset state
-  CLRTMS;
-  jtag_tcktock();  // now in Run-Test/Idle state
+//! Get into Capture-DR state
+void jtag_capture_dr()
+{
+	// assumes you're in Run-Test/Idle, Update-DR or Update-IR
+	if (!in_state(RUN_TEST_IDLE | UPDATE_DR | UPDATE_IR))
+	{
+		debugstr("Invalid JTAG state");
+		return;
+	}
+
+	CLRMOSI;
+	SETTMS;
+	jtag_tcktock(); // Select-DR-Scan
+	CLRTMS;
+	jtag_tcktock(); // Capture-IR
+
+	jtag_state = CAPTURE_DR;
 }
 
+//! Gets back to run-test-idle without going through the test-logic-reset
+void jtag_run_test_idle()
+{
+	CLRMOSI;
+
+	if (in_state(SELECT_DR_SCAN | SELECT_IR_SCAN))
+	{
+		CLRTMS;
+		jtag_tcktock();
+		jtag_state <<= 1; //CAPTURE_DR or CAPTURE_IR
+	}
+
+	if (in_state(CAPTURE_DR | CAPTURE_IR))
+	{
+		SETTMS;
+		jtag_tcktock();
+		jtag_state <<= 2; //EXIT1_DR or EXIT1_IR
+	}
+
+	if (in_state(SHIFT_DR | SHIFT_IR))
+	{
+		SETTMS;
+		jtag_tcktock();
+		jtag_state <<= 1; //EXIT1_DR or EXIT1_IR
+	}
+
+	if (in_state(EXIT1_DR | EXIT1_IR))
+	{
+		SETTMS;
+		jtag_tcktock();
+		jtag_state <<=3; //UPDATE_DR or UPDATE_IR
+	}
+
+	if (in_state(PAUSE_DR | PAUSE_IR))
+	{
+		SETTMS;
+		jtag_tcktock();
+		jtag_state <<= 1; // EXIT2_DR or EXIT2_IR
+	}
+
+	if (in_state(EXIT2_DR | EXIT2_IR))
+	{
+		SETTMS;
+		jtag_tcktock();
+		jtag_state <<= 1; // UPDATE_DR or UPDATE_IR
+	}
+
+	if (in_state(UPDATE_DR | UPDATE_IR | TEST_LOGIC_RESET))
+	{
+		CLRTMS;
+		jtag_tcktock();
+		jtag_state = RUN_TEST_IDLE;
+	}
+}
 
-int savedtclk=0;
-//  NOTE: important: THIS MODULE REVOLVES AROUND RETURNING TO RUNTEST/IDLE, OR 
-//  THE FUNCTIONAL EQUIVALENT
-//! Shift N bits over TDI/TDO.  May choose LSB or MSB, and select whether to 
-//  terminate (TMS-high on last bit) and whether to return to RUNTEST/IDLE
-//      flags should be 0 for most uses.  
-//      for the extreme case, flags should be  (NOEND|NORETDLE|LSB)
-//      other edge cases can involve a combination of those three flags
+int savedtclk;
+//	NOTE: important: THIS MODULE REVOLVES AROUND RETURNING TO RUNTEST/IDLE, OR 
+//	THE FUNCTIONAL EQUIVALENT
+//! Shift N bits over TDI/TDO.	May choose LSB or MSB, and select whether to 
+//	terminate (TMS-high on last bit) and whether to return to RUNTEST/IDLE
+//		flags should be 0 for most uses.  
+//		for the extreme case, flags should be  (NOEND|NORETDLE|LSB)
+//		other edge cases can involve a combination of those three flags
 //
-//      the max bit-size that can be be shifted is 32-bits.  
-//      for longer shifts, use the NOEND flag (which infers NORETIDLE so the 
-//      additional flag is unnecessary)
+//		the max bit-size that can be be shifted is 32-bits.  
+//		for longer shifts, use the NOEND flag (which infers NORETIDLE so the 
+//		additional flag is unnecessary)
 //
-//      NORETIDLE is used for special cases where (as with arm) the debug 
-//      subsystem does not want to return to the RUN-TEST/IDLE state between 
-//      setting IR and DR
-unsigned long jtagtransn(unsigned long word, 
-                         unsigned char bitcount, 
-                         unsigned char flags) {
-  unsigned char bit;
-  unsigned long high = 1L;
-  unsigned long mask;
-
-  //for (bit=(bitcount-1)/8; bit>0; bit--)
-  //  high <<= 8;
-  //high <<= ((bitcount-1)%8);
-  high <<= (bitcount-1);
-
-  mask = high-1;
-
-  SAVETCLK;
-  if (flags & LSB) {
-    for (bit = bitcount; bit > 0; bit--) {
-      /* write MOSI on trailing edge of previous clock */
-      if (word & 1)
-        {SETMOSI;}
-      else
-        {CLRMOSI;}
-      word >>= 1;
-
-      if (bit==1 && !(flags & NOEND))
-        SETTMS;//TMS high on last bit to exit.
-       
-      jtag_tcktock();
-
-      /* read MISO on trailing edge */
-      if (READMISO){
-        word += (high);
-      }
-    }
-  } else {
-    for (bit = bitcount; bit > 0; bit--) {
-      /* write MOSI on trailing edge of previous clock */
-      if (word & high)
-        {SETMOSI;}
-      else
-        {CLRMOSI;}
-      word = (word & mask) << 1;
-
-      if (bit==1 && !(flags & NOEND))
-        SETTMS;//TMS high on last bit to exit.
-
-      jtag_tcktock();
-
-      /* read MISO on trailing edge */
-      word |= (READMISO);
-    }
-  }
- 
-
-  RESTORETCLK;
-  //SETMOSI;
-
-  if (!(flags & NOEND)){
-    // exit state
-    jtag_tcktock();
-    // update state
-    if (!(flags & NORETIDLE)){
-      CLRTMS;
-      jtag_tcktock();
-    }
-  }
-  return word;
-}
+//		NORETIDLE is used for special cases where (as with arm) the debug 
+//		subsystem does not want to return to the RUN-TEST/IDLE state between 
+//		setting IR and DR
+uint32_t jtag_trans_n(uint32_t word, 
+					  uint8_t bitcount, 
+					  enum eTransFlags flags) 
+{
+	uint8_t bit;
+	uint32_t high = (1L << (bitcount - 1));
+	uint32_t mask = high - 1;
 
-//! Shift 8 bits in and out.
-unsigned char jtagtrans8(unsigned char byte){
-  unsigned int bit;
-  SAVETCLK;
-  for (bit = 0; bit < 8; bit++) {
-    /* write MOSI on trailing edge of previous clock */
-    if (byte & 0x80)
-      {SETMOSI;}
-    else
-      {CLRMOSI;}
-    byte <<= 1;
-    
-    if(bit==7)
-      SETTMS;//TMS high on last bit to exit.
-    
-    TCKTOCK;
-    /* read MISO on trailing edge */
-    byte |= READMISO;
-  }
-  RESTORETCLK;
-  
-  // exit state
-  TCKTOCK;
-  // update state
-  CLRTMS;
-  TCKTOCK;
-  
-  return byte;
-}
+	if (!in_state(SHIFT_IR | SHIFT_DR))
+	{
+		debugstr("jtag_trans_n from invalid TAP state");
+		return 0;
+	}
+
+	SAVETCLK;
+
+	if (flags & LSB) 
+	{
+		for (bit = bitcount; bit > 0; bit--) 
+		{
+			/* write MOSI on trailing edge of previous clock */
+			if (word & 1)
+			{
+				SETMOSI;
+			}
+			else
+			{
+				CLRMOSI;
+			}
+			word >>= 1;
+
+			if ((bit == 1) && !(flags & NOEND))
+				SETTMS; //TMS high on last bit to exit.
+
+			jtag_tcktock();
+
+			if ((bit == 1) && !(flags & NOEND))
+				jtag_state <<= 1; // Exit1-DR or Exit1-IR
+
+			/* read MISO on trailing edge */
+			if (READMISO)
+			{
+				word += (high);
+			}
+		}
+	} 
+	else 
+	{
+		for (bit = bitcount; bit > 0; bit--) 
+		{
+			/* write MOSI on trailing edge of previous clock */
+			if (word & high)
+			{
+				SETMOSI;
+			}
+			else
+			{
+				CLRMOSI;
+			}
+			word = (word & mask) << 1;
+
+			if ((bit==1) && !(flags & NOEND))
+				SETTMS; //TMS high on last bit to exit.
+
+			jtag_tcktock();
+
+			if ((bit == 1) && !(flags & NOEND))
+				jtag_state <<= 1; // Exit1-DR or Exit1-IR
+
+			/* read MISO on trailing edge */
+			word |= (READMISO);
+		}
+	}
+
+	RESTORETCLK;
+
+	if (!(flags & NOEND))
+	{
+		// exit state
+		jtag_tcktock();
 
-//! Shift n bits in and out.
-/*unsigned long jtagtransn(unsigned long word,
-			 unsigned int bitcount){
-  unsigned int bit;
-  //0x8000
-  unsigned long high=0x8000;
-  
-  if(bitcount==20)
-    high=0x80000;
-  if(bitcount==16)
-    high= 0x8000;
-  
-  SAVETCLK;
-  
-  for (bit = 0; bit < bitcount; bit++) {
-    // write MOSI on trailing edge of previous clock *
-    if (word & high)
-      {SETMOSI;}
-    else
-      {CLRMOSI;}
-    word <<= 1;
-    
-    if(bit==bitcount-1)
-      SETTMS;//TMS high on last bit to exit.
-    
-    TCKTOCK;
-    // read MISO on trailing edge *
-    word |= READMISO;
-  }
-  
-  if(bitcount==20){
-    word = ((word << 16) | (word >> 4)) & 0x000FFFFF;
-  }
-  
-  RESTORETCLK;
-  
-  // exit state
-  TCKTOCK;
-  // update state
-  CLRTMS;
-  TCKTOCK;
-  
-  return word;
+		jtag_state <<= 3; // Update-DR or Update-IR
+
+		// update state
+		if (!(flags & NORETIDLE))
+		{
+			CLRTMS;
+			jtag_tcktock();
+
+			jtag_state = RUN_TEST_IDLE;
+		}
+	}
+
+	return word;
 }
-*/
 
-//! Stop JTAG, release pins
-void jtag_stop(){
-  P5OUT=0;
-  P4OUT=0;
+//! Detects the width of the IR register
+uint16_t jtag_detect_ir_width()
+{
+	int i;
+	uint16_t width = 0;
+
+	if (!in_run_test_idle())
+	{
+		debugstr("Not in run-test-idle state");
+		return 0;
+	}
+
+	// get to shift-ir state
+	jtag_capture_ir();
+	jtag_shift_register();
+
+	// first we shift in 1024 zeros
+	CLRMOSI;
+	for(i = 0; i < 1024; i++)
+	{
+		jtag_tcktock();
+	}
+
+	// now we'll clock in ones until we see one
+	SETMOSI;
+	for(i = 0; i < 1024; i++)
+	{
+		jtag_tcktock();
+		if(READMISO)
+			break;
+		width++;
+	}
+
+	// now get back to run-test-idle
+	jtag_run_test_idle();
+
+	return width;
 }
 
-unsigned int drwidth=16;
-//! Shift all bits of the DR.
-unsigned long jtag_dr_shift20(unsigned long in){
-  // idle
-  SETTMS;
-  TCKTOCK;
-  // select DR
-  CLRTMS;
-  TCKTOCK;
-  // capture IR
-  TCKTOCK;
-  
-  // shift DR, then idle
-  return(jtagtransn(in,20,0));
+//! Detects how many TAPs are in the JTAG chain
+uint16_t jtag_detect_chain_length()
+{
+	int i;
+	int bit;
+	uint16_t length = 0;
+
+	if (!in_run_test_idle())
+	{
+		debugstr("detect chain length must start from run-test-idle");
+		return 0;
+	}
+
+	// The standard JTAG instruction for "bypass" mode is to set all 1's in the
+	// instruction register.  When in "bypass" mode, the DR acts like a 1-bit
+	// shift regiser.  So we can use that to detect how many TAPs are in the 
+	// chain.
+	
+	// first get into shift IR mode
+	jtag_capture_ir();
+	jtag_shift_register();
+
+	// then we flood the IR chain with all 1's to put all device's DRs
+	// into bypass mode
+	CLRTMS;
+	SETMOSI;
+	for (i = 0; i < 1024; i++)
+	{
+		if (i == 1023)
+			SETTMS; // exit on last bit
+		jtag_tcktock();
+	}
+	jtag_state = EXIT1_IR;
+
+	// go to Update-IR
+	CLRMOSI;
+	jtag_tcktock();
+	jtag_state = UPDATE_IR;
+
+	// go to Shift-DR state
+	jtag_capture_dr();
+	jtag_shift_register();
+
+	// flush the DR's with zeros
+	CLRTMS;
+	CLRMOSI;
+	for (i = 0; i < 1024; i++)
+	{
+		jtag_tcktock();
+	}
+
+	// send 1's into the DRs until we see one come out the other side
+	SETMOSI;
+	for (i = 0; i < 1024; i++)
+	{
+		jtag_tcktock();
+		bit = READMISO;
+		if (bit)
+			break;
+		length++;
+	}
+
+	// now get back to run-test-idle
+	jtag_run_test_idle();
+
+	return length;
 }
 
+//! Gets device ID for specified chip in the chain
+uint32_t jtag_get_device_id(int chip)
+{
+	int i;
+	uint16_t chain_length;
+	uint32_t id = 0;
+
+	// reset everything
+	jtag_reset_tap();
 
-//! Shift 16 bits of the DR.
-unsigned int jtag_dr_shift16(unsigned int in){
-  // idle
-  SETTMS;
-  TCKTOCK;
-  // select DR
-  CLRTMS;
-  TCKTOCK;
-  // capture IR
-  TCKTOCK;
-  
-  // shift DR, then idle
-  return(jtagtransn(in,16,0));
+	// figure out how many devices are in the chain
+	chain_length = jtag_detect_chain_length();
+
+	if (chip >= chain_length)
+	{
+		debugstr("invalid part index");
+		return 0;
+	}
+
+	// reset everything again because going through test-logic-reset forces
+	// all IR's to have their manufacturer specific instruction for IDCODE
+	// and loads the DR's with the chip's ID code.
+	jtag_reset_tap();
+
+	// get into shift DR state
+	jtag_capture_dr();
+	jtag_shift_register();
+
+	// read out the 32-bit ID codes for each device
+	CLRTMS;
+	CLRMOSI;
+	for (i = 0; i < (chip + 1); i++)
+	{
+		id = jtag_trans_n(0xFFFFFFFF, 32, LSB | NOEND | NORETIDLE);
+	}
+
+	jtag_run_test_idle();
+
+	return id;
 }
 
-//! Shift native width of the DR
-unsigned long jtag_dr_shiftadr(unsigned long in){
-  unsigned long out=0;
-  
-  // idle
-  SETTMS;
-  TCKTOCK;
-  // select DR
-  CLRTMS;
-  TCKTOCK;
-  // capture IR
-  TCKTOCK;
-
-  
-  out=jtagtransn(in,drwidth,0);
-  
-  // shift DR, then idle
-  return(out);
+//! Shift 8 bits in/out of selected register
+uint8_t jtag_trans_8(uint8_t in)
+{
+	uint32_t out = jtag_trans_n((uint32_t)in, 8, MSB);
+	return (uint8_t)(0x000000FF & out);
 }
 
+//! Shift 16 bits in/out of selected register
+uint16_t jtag_trans_16(uint16_t in)
+{
+	uint32_t out = jtag_trans_n((uint32_t)in, 16, MSB);
+	return (uint16_t)(0x0000FFFF & out);
+}
 
 //! Shift 8 bits of the IR.
-unsigned char jtag_ir_shift8(unsigned char in){
-  // idle
-  SETTMS;
-  TCKTOCK;
-  // select DR
-  TCKTOCK;
-  // select IR
-  CLRTMS;
-  TCKTOCK;
-  // capture IR
-  TCKTOCK;
-  
-  // shift IR, then idle.
-  return(jtagtrans8(in));
+uint8_t jtag_ir_shift_8(uint8_t in)
+{
+	if (!in_run_test_idle())
+	{
+		debugstr("Not in run-test-idle state");
+		return 0;
+	}
+
+	// get intot the right state
+	jtag_capture_ir();
+	jtag_shift_register();
+
+	// shift IR bits
+	return jtag_trans_8(in);
+}
+
+//! Shift 16 bits of the DR.
+uint16_t jtag_dr_shift_16(uint16_t in)
+{
+
+	if (!in_run_test_idle())
+	{
+		debugstr("Not in run-test-idle state");
+		return 0;
+	}
+
+	// get intot the right state
+	jtag_capture_dr();
+	jtag_shift_register();
+
+	// shift DR, then idle
+	return jtag_trans_16(in);
 }
 
 //! Handles a monitor command.
@@ -333,32 +552,56 @@ void jtag_handle_fn(uint8_t const app,
 {
 	switch(verb)
 	{
-		//START handled by specific JTAG
+	// START handled by specific JTAG
 	case STOP:
 		jtag_stop();
 		txdata(app,verb,0);
 		break;
 
 	case SETUP:
-		jtagsetup();
+		jtag_setup();
 		txdata(app,verb,0);
 		break;
 
 	case JTAG_IR_SHIFT:
-		cmddata[0]=jtag_ir_shift8(cmddata[0]);
+		cmddata[0] = jtag_ir_shift_8(cmddata[0]);
 		txdata(app,verb,1);
 		break;
 
 	case JTAG_DR_SHIFT:
-		cmddataword[0]=jtag_dr_shift16(cmddataword[0]);
+		cmddataword[0] = htons(jtag_dr_shift_16(ntohs(cmddataword[0])));
 		txdata(app,verb,2);
 		break;
 
-	case JTAG_RESETTAP:
-		jtag_resettap();
+	case JTAG_RESET_TAP:
+		jtag_reset_tap();
 		txdata(app,verb,0);
 		break;
 
+	case JTAG_RESET_TARGET:
+		jtag_reset_tap();
+		jtag_reset_target();
+		txdata(app,verb,0);
+		break;
+
+	case JTAG_DETECT_IR_WIDTH:
+		jtag_reset_tap();
+		cmddataword[0] = htons(jtag_detect_ir_width());
+		txdata(app,verb,2);
+		break;
+
+	case JTAG_DETECT_CHAIN_LENGTH:
+		jtag_reset_tap();
+		cmddataword[0] = htons(jtag_detect_chain_length());
+		txdata(app,verb,2);
+		break;
+
+	case JTAG_GET_DEVICE_ID:
+		jtag_reset_tap();
+		cmddatalong[0] = htonl(jtag_get_device_id(ntohs(cmddataword[0])));
+		txdata(app,verb,4);
+		break;
+
 	default:
 		txdata(app,NOK,0);
 	}