+#!/bin/env python3
+import os
+
+from nmigen import *
+from nmigen.build import *
+from nmigen.lib.io import *
+
+from wishbone import Wishbone
+
+__all__ = [
+ "PmodJTAGMasterResource",
+ "PmodJTAGMasterAResource",
+ "PmodJTAGSlaveResource",
+ "PmodJTAGSlaveAResource",
+ "JTAG",
+]
+
+#TODO: Provide more documentation
+
+def PmodJTAGMasterResource(name, number, *, pmod, attrs=Attrs(IOSTANDARD="LVCMOS33")):
+ return Resource(name, number,
+ Subsignal("TCK", Pins("1", dir="o", conn=("pmod", pmod))),
+ Subsignal("TMS", Pins("2", dir="o", conn=("pmod", pmod))),
+ Subsignal("TDO", Pins("3", dir="o", conn=("pmod", pmod))),
+ Subsignal("TDI", Pins("4", dir="i", conn=("pmod", pmod))),
+ attrs,
+ )
+
+def PmodJTAGMasterAResource(name, number, *, pmod, attrs=Attrs(IOSTANDARD="LVCMOS33")):
+ return Resource(name, number,
+ Subsignal("TCK", Pins("1", dir="o", conn=("pmod", pmod))),
+ Subsignal("TMS", Pins("2", dir="o", conn=("pmod", pmod))),
+ Subsignal("TDO", Pins("3", dir="o", conn=("pmod", pmod))),
+ Subsignal("TDI", Pins("4", dir="i", conn=("pmod", pmod))),
+ Subsignal("TRST", PinsN("7", dir="o", conn=("pmod", pmod))),
+ attrs,
+ )
+
+def PmodJTAGSlaveResource(name, number, *, pmod, attrs=Attrs(IOSTANDARD="LVCMOS33")):
+ return Resource(name, number,
+ Subsignal("TCK", Pins("1", dir="i", conn=("pmod", pmod))),
+ Subsignal("TMS", Pins("2", dir="i", conn=("pmod", pmod))),
+ Subsignal("TDI", Pins("3", dir="i", conn=("pmod", pmod))),
+ Subsignal("TDO", Pins("4", dir="o", conn=("pmod", pmod))),
+ attrs,
+ )
+
+def PmodJTAGSlaveAResource(name, number, *, pmod, attrs=Attrs(IOSTANDARD="LVCMOS33")):
+ return Resource(name, number,
+ Subsignal("TCK", Pins("1", dir="i", conn=("pmod", pmod))),
+ Subsignal("TMS", Pins("2", dir="i", conn=("pmod", pmod))),
+ Subsignal("TDI", Pins("3", dir="i", conn=("pmod", pmod))),
+ Subsignal("TDO", Pins("4", dir="o", conn=("pmod", pmod))),
+ Subsignal("TRST", PinsN("7", dir="i", conn=("pmod", pmod))),
+ attrs,
+ )
+
+
+class ShiftReg(Elaboratable):
+ def __init__(self, ircodes, length, domain):
+ # The sr record will be returned to user code
+ self.sr = Record([("i", length), ("o", length), ("oe", len(ircodes)), ("ack", 1)])
+ # The next attributes are for JTAG class usage only
+ self.ir = None # made None as width is not known yet
+ self.tdi = Signal()
+ self.tdo = Signal()
+ self.tdo_en = Signal()
+ self.capture = Signal()
+ self.shift = Signal()
+ self.update = Signal()
+ self.jtag_cd = None # The JTAG clock domain
+
+ ##
+
+ self._ircodes = ircodes
+ self._domain = domain
+
+ def elaborate(self, platform):
+ length = len(self.sr.o)
+ domain = self._domain
+
+ m = Module()
+
+ m.domains.jtag = self.jtag_cd
+
+ sr_jtag = Signal(length)
+
+ assert isinstance(self.ir, Signal)
+ isir = Signal(len(self._ircodes))
+ capture = Signal()
+ shift = Signal()
+ update = Signal()
+ m.d.comb += [
+ isir.eq(Cat(self.ir == ircode for ircode in self._ircodes)),
+ capture.eq((isir != 0) & self.capture),
+ shift.eq((isir != 0) & self.shift),
+ update.eq((isir != 0) & self.update),
+ ]
+
+ # On update set o, oe and wait for ack
+ # update signal is on JTAG clockdomain, latch it
+ update_core = Signal()
+ m.d[domain] += update_core.eq(update) # This is CDC from JTAG domain to given domain
+ with m.FSM(domain=domain):
+ with m.State("IDLE"):
+ m.d.comb += self.sr.oe.eq(0)
+ with m.If(update_core):
+ # Latch sr_jtag cross domain but it should be stable due to latching of update_core
+ m.d[domain] += self.sr.o.eq(sr_jtag)
+ # Wait one cycle to raise oe so sr.o has one more cycle to stabilize
+ m.next = "WAIT4ACK"
+ with m.State("WAIT4ACK"):
+ m.d.comb += self.sr.oe.eq(isir)
+ with m.If(self.sr.ack):
+ m.next = "WAIT4END"
+ with m.State("WAIT4END"):
+ m.d.comb += self.sr.oe.eq(0)
+ with m.If(~update_core):
+ m.next = "IDLE"
+
+ m.d.comb += [
+ self.tdo.eq(sr_jtag[0]),
+ self.tdo_en.eq(shift),
+ ]
+
+ with m.If(shift):
+ m.d.jtag += sr_jtag.eq(Cat(sr_jtag[1:], self.tdi))
+ with m.If(capture):
+ m.d.jtag += sr_jtag.eq(self.sr.i)
+
+ return m
+
+class JTAGWishbone(Elaboratable):
+ def __init__(self, sr_addr, sr_data, wb, domain):
+ self._sr_addr = sr_addr
+ self._sr_data = sr_data
+ self._wb = wb
+ self._domain = domain
+
+ # To be set by JTAG
+ self._ir = None
+
+ def elaborate(self, platform):
+ sr_addr = self._sr_addr
+ sr_data = self._sr_data
+ wb = self._wb
+ domain = self._domain
+ ir = self._ir
+
+ m = Module()
+
+ if hasattr(wb, "sel"):
+ # Always selected
+ m.d.comb += [s.eq(1) for s in wb.sel]
+
+ # Immediately ack oe
+ m.d[domain] += [
+ sr_addr.ack.eq(sr_addr.oe),
+ sr_data.ack.eq(sr_data.oe != 0),
+ ]
+
+ with m.FSM(domain=domain) as fsm:
+ with m.State("IDLE"):
+ m.d.comb += [
+ wb.cyc.eq(0),
+ wb.stb.eq(0),
+ wb.we.eq(0),
+ ]
+ with m.If(sr_addr.oe): # WBADDR code
+ m.d[domain] += wb.addr.eq(sr_addr.o)
+ m.next = "READ"
+ with m.If(sr_data.oe[0]): # WBREAD code
+ m.d[domain] += wb.addr.eq(wb.addr + 1)
+ m.next = "READ"
+ with m.If(sr_data.oe[1]): # WBWRITE code
+ m.d[domain] += wb.dat_w.eq(sr_data.o)
+ m.next = "WRITEREAD"
+ with m.State("READ"):
+ m.d.comb += [
+ wb.cyc.eq(1),
+ wb.stb.eq(1),
+ wb.we.eq(0),
+ ]
+ with m.If(~wb.stall):
+ m.next = "READACK"
+ with m.State("READACK"):
+ m.d.comb += [
+ wb.cyc.eq(1),
+ wb.stb.eq(0),
+ wb.we.eq(0),
+ ]
+ with m.If(wb.ack):
+ m.d[domain] += sr_data.i.eq(wb.dat_r)
+ m.next = "IDLE"
+ with m.State("WRITEREAD"):
+ m.d.comb += [
+ wb.cyc.eq(1),
+ wb.stb.eq(1),
+ wb.we.eq(1),
+ ]
+ with m.If(~wb.stall):
+ m.next = "WRITEREADACK"
+ with m.State("WRITEREADACK"):
+ m.d.comb += [
+ wb.cyc.eq(1),
+ wb.stb.eq(0),
+ wb.we.eq(0),
+ ]
+ with m.If(wb.ack):
+ m.d[domain] += wb.addr.eq(wb.addr + 1)
+ m.next = "READ"
+
+ return m
+
+
+class JTAG(Elaboratable):
+ @staticmethod
+ def _add_files(platform, prefix):
+ d = os.path.realpath("{0}{1}{2}{1}vhdl".format(
+ os.path.dirname(__file__), os.path.sep, os.path.pardir
+ )) + os.path.sep
+ for fname in [
+ "c4m_jtag_pkg.vhdl",
+ "c4m_jtag_idblock.vhdl",
+ "c4m_jtag_iocell.vhdl",
+ "c4m_jtag_ioblock.vhdl",
+ "c4m_jtag_irblock.vhdl",
+ "c4m_jtag_tap_fsm.vhdl",
+ "c4m_jtag_tap_controller.vhdl",
+ ]:
+ f = open(d + fname, "r")
+ platform.add_file(prefix + fname, f)
+ f.close()
+
+
+ def __init__(self, io_count, *, ir_width=None, manufacturer_id=Const(0b10001111111, 11),
+ part_number=Const(1, 16), version=Const(0, 4)
+ ):
+ assert(isinstance(io_count, int) and io_count > 0)
+ assert((ir_width is None) or (isinstance(ir_width, int) and ir_width >= 2))
+ assert(len(version) == 4)
+
+ # TODO: Handle IOs with different directions
+ self.tck = Signal()
+ self.tms = Signal()
+ self.tdo = Signal()
+ self.tdi = Signal()
+ self.core = Array(Pin(1, "io") for _ in range(io_count)) # Signals to use for core
+ self.pad = Array(Pin(1, "io") for _ in range(io_count)) # Signals going to IO pads
+
+ self.jtag_cd = ClockDomain(name="jtag", local=True) # Own clock domain using TCK as clock signal
+
+ ##
+
+ self._io_count = io_count
+ self._ir_width = ir_width
+ self._manufacturer_id = manufacturer_id
+ self._part_number = part_number
+ self._version = version
+
+ self._ircodes = [0, 1, 2] # Already taken codes, all ones added at the end
+ self._srs = []
+
+ self._wbs = []
+
+ def elaborate(self, platform):
+ JTAG._add_files(platform, "jtag" + os.path.sep)
+
+ m = Module()
+
+ tdo_jtag = Signal()
+ reset = Signal()
+ capture = Signal()
+ shift = Signal()
+ update = Signal()
+
+
+ ir_max = max(self._ircodes) + 1 # One extra code needed with all ones
+ ir_width = len("{:b}".format(ir_max))
+ if self._ir_width is not None:
+ assert self._ir_width >= ir_width, "Specified JTAG IR width not big enough for allocated shiift registers"
+ ir_width = self._ir_width
+ ir = Signal(ir_width)
+
+ core_i = Cat(pin.i for pin in self.core)
+ core_o = Cat(pin.o for pin in self.core)
+ core_oe = Cat(pin.oe for pin in self.core)
+ pad_i = Cat(pin.i for pin in self.pad)
+ pad_o = Cat(pin.o for pin in self.pad)
+ pad_oe = Cat(pin.oe for pin in self.pad)
+
+ params = {
+ "p_IOS": self._io_count,
+ "p_IR_WIDTH": ir_width,
+ "p_MANUFACTURER": self._manufacturer_id,
+ "p_PART_NUMBER": self._part_number,
+ "p_VERSION": self._version,
+ "i_TCK": self.tck,
+ "i_TMS": self.tms,
+ "i_TDI": self.tdi,
+ "o_TDO": tdo_jtag,
+ "i_TRST_N": Const(1),
+ "o_RESET": reset,
+ "o_DRCAPTURE": capture,
+ "o_DRSHIFT": shift,
+ "o_DRUPDATE": update,
+ "o_IR": ir,
+ "o_CORE_IN": core_i,
+ "i_CORE_OUT": core_o,
+ "i_CORE_EN": core_oe,
+ "i_PAD_IN": pad_i,
+ "o_PAD_OUT": pad_o,
+ "o_PAD_EN": pad_oe,
+ }
+ m.submodules.tap = Instance("c4m_jtag_tap_controller", **params)
+
+ m.d.comb += [
+ self.jtag_cd.clk.eq(self.tck),
+ self.jtag_cd.rst.eq(reset),
+ ]
+
+ for i, sr in enumerate(self._srs):
+ m.submodules["sr{}".format(i)] = sr
+ sr.ir = ir
+ m.d.comb += [
+ sr.tdi.eq(self.tdi),
+ sr.capture.eq(capture),
+ sr.shift.eq(shift),
+ sr.update.eq(update),
+ ]
+
+ if len(self._srs) > 0:
+ first = True
+ for sr in self._srs:
+ if first:
+ first = False
+ with m.If(sr.tdo_en):
+ m.d.comb += self.tdo.eq(sr.tdo)
+ else:
+ with m.Elif(sr.tdo_en):
+ m.d.comb += self.tdo.eq(sr.tdo)
+ with m.Else():
+ m.d.comb += self.tdo.eq(tdo_jtag)
+ else:
+ m.d.comb += self.tdo.eq(tdo_jtag)
+
+ for i, wb in enumerate(self._wbs):
+ m.submodules["wb{}".format(i)] = wb
+ wb._ir = ir
+
+ return m
+
+
+ def add_shiftreg(self, ircode, length, domain="sync"):
+ """Add a shift register to the JTAG interface
+
+ Parameters:
+ - ircode: code(s) for the IR; int or sequence of ints. In the latter case this
+ shiftreg is shared between different IR codes.
+ - length: the length of the shift register
+ - domain: the domain on which the signal will be used"""
+
+ try:
+ ir_it = iter(ircode)
+ ircodes = ircode
+ except TypeError:
+ ir_it = ircodes = (ircode,)
+ for _ircode in ir_it:
+ assert(isinstance(_ircode, int) and _ircode > 0 and _ircode not in self._ircodes)
+
+ sr = ShiftReg(ircodes, length, domain)
+ sr.jtag_cd = self.jtag_cd
+ self._ircodes.extend(ircodes)
+ self._srs.append(sr)
+
+ return sr.sr
+
+
+ def add_wishbone(self, ircodes, address_width, data_width, sel_width=None, domain="sync"):
+ """Add a wishbone interface
+
+ Parameters:
+ - ircodes: sequence of three integer for the JTAG IR codes;
+ they represent resp. WBADDR, WBREAD and WBREADWRITE. First code
+ has a shift register of length 'address_width', the two other codes
+ share a shift register of length data_width.
+ - address_width: width of the address
+ - data_width: width of the data"""
+
+ assert len(ircodes) == 3
+
+ sr_addr = self.add_shiftreg(ircodes[0], address_width, domain=domain)
+ sr_data = self.add_shiftreg(ircodes[1:], data_width, domain=domain)
+
+ wb = Wishbone(data_width=data_width, address_width=address_width, sel_width=sel_width, master=True)
+
+ self._wbs.append(JTAGWishbone(sr_addr, sr_data, wb, domain))
+
+ return wb
projects / c4m-jtag.git / commitdiff