3 from enum
import Enum
, auto
5 from nmigen
import (Elaboratable
, Signal
, Module
, ClockDomain
, Cat
, Record
,
7 from nmigen
.hdl
.rec
import Direction
, Layout
8 from nmigen
.tracer
import get_var_name
10 from nmigen_soc
.wishbone
import Interface
as WishboneInterface
12 from .bus
import Interface
, DMIInterface
15 "TAP", "ShiftReg", "IOType", "IOConn",
19 class _FSM(Elaboratable
):
20 """TAP subblock for the FSM"""
21 def __init__(self
, *, bus
):
24 self
.capture
= Signal()
26 self
.update
= Signal()
28 self
.posjtag
= ClockDomain("posjtag", local
=True)
29 self
.negjtag
= ClockDomain("negjtag", local
=True, clk_edge
="neg")
33 def elaborate(self
, platform
):
38 self
.posjtag
.clk
.eq(self
._bus
.tck
),
39 self
.posjtag
.rst
.eq(rst
),
40 self
.negjtag
.clk
.eq(self
._bus
.tck
),
41 self
.negjtag
.rst
.eq(rst
),
44 # Make local clock domain optionally using trst of JTAG bus as reset
45 if hasattr(self
._bus
, "trst"):
46 m
.domains
.local
= local
= ClockDomain(local
=True)
47 m
.d
.comb
+= local
.rst
.eq(self
._bus
.trst
)
49 m
.domains
.local
= local
= ClockDomain(local
=True, reset_less
=True)
50 m
.d
.comb
+= local
.clk
.eq(self
._bus
.tck
)
52 with m
.FSM(domain
="local") as fsm
:
53 with m
.State("TestLogicReset"):
54 # Be sure to reset isir, isdr
59 with m
.If(self
._bus
.tms
== 0):
60 m
.next
= "RunTestIdle"
61 with m
.State("RunTestIdle"):
62 # Be sure to reset isir, isdr
67 with m
.If(self
._bus
.tms
== 1):
68 m
.next
= "SelectDRScan"
69 with m
.State("SelectDRScan"):
70 with m
.If(self
._bus
.tms
== 0):
71 m
.d
.local
+= self
.isdr
.eq(1)
72 m
.next
= "CaptureState"
74 m
.next
= "SelectIRScan"
75 with m
.State("SelectIRScan"):
76 with m
.If(self
._bus
.tms
== 0):
77 m
.d
.local
+= self
.isir
.eq(1)
78 m
.next
= "CaptureState"
80 m
.next
= "TestLogicReset"
81 with m
.State("CaptureState"):
82 with m
.If(self
._bus
.tms
== 0):
86 with m
.State("ShiftState"):
87 with m
.If(self
._bus
.tms
== 1):
89 with m
.State("Exit1"):
90 with m
.If(self
._bus
.tms
== 0):
93 m
.next
= "UpdateState"
94 with m
.State("Pause"):
95 with m
.If(self
._bus
.tms
== 1):
97 with m
.State("Exit2"):
98 with m
.If(self
._bus
.tms
== 0):
101 m
.next
= "UpdateState"
102 with m
.State("UpdateState"):
107 with m
.If(self
._bus
.tms
== 0):
108 m
.next
= "RunTestIdle"
110 m
.next
= "SelectDRScan"
113 rst
.eq(fsm
.ongoing("TestLogicReset")),
114 self
.capture
.eq(fsm
.ongoing("CaptureState")),
115 self
.shift
.eq(fsm
.ongoing("ShiftState")),
116 self
.update
.eq(fsm
.ongoing("UpdateState")),
121 class _IRBlock(Elaboratable
):
122 """TAP subblock for handling the IR shift register"""
123 def __init__(self
, *, ir_width
, cmd_idcode
,
124 tdi
, capture
, shift
, update
,
127 self
.ir
= Signal(ir_width
, reset
=cmd_idcode
)
131 self
._capture
= capture
133 self
._update
= update
135 def elaborate(self
, platform
):
138 shift_ir
= Signal(len(self
.ir
), reset_less
=True)
140 m
.d
.comb
+= self
.tdo
.eq(self
.ir
[0])
141 with m
.If(self
._capture
):
142 m
.d
.posjtag
+= shift_ir
.eq(self
.ir
)
143 with m
.Elif(self
._shift
):
144 m
.d
.posjtag
+= shift_ir
.eq(Cat(shift_ir
[1:], self
._tdi
))
145 with m
.Elif(self
._update
):
146 # For ir we only update it on the rising edge of clock
147 # to avoid that we already have the new ir value when still in
149 m
.d
.posjtag
+= self
.ir
.eq(shift_ir
)
159 class IOConn(Record
):
167 """TAP subblock representing the interface for an JTAG IO cell.
168 It contains signal to connect to the core and to the pad
170 This object is normally only allocated and returned from ``TAP.add_io``
171 It is a Record subclass.
175 core: subrecord with signals for the core
176 i: Signal(1), present only for IOType.In and IOType.InTriOut.
177 Signal input to core with pad input value.
178 o: Signal(1), present only for IOType.Out, IOType.TriOut and
180 Signal output from core with the pad output value.
181 oe: Signal(1), present only for IOType.TriOut and IOType.InTriOut.
182 Signal output from core with the pad output enable value.
183 pad: subrecord with for the pad
184 i: Signal(1), present only for IOType.In and IOType.InTriOut
185 Output from pad with pad input value for core.
186 o: Signal(1), present only for IOType.Out, IOType.TriOut and
188 Input to pad with pad output value.
189 oe: Signal(1), present only for IOType.TriOut and IOType.InTriOut.
190 Input to pad with pad output enable value.
195 if iotype
in (IOType
.In
, IOType
.InTriOut
):
196 sigs
.append(("i", 1))
197 if iotype
in (IOType
.Out
, IOType
.TriOut
, IOType
.InTriOut
):
198 sigs
.append(("o", 1))
199 if iotype
in (IOType
.TriOut
, IOType
.InTriOut
):
200 sigs
.append(("oe", 1))
202 return Layout((("core", sigs
), ("pad", sigs
)))
204 def __init__(self
, *, iotype
, name
=None, src_loc_at
=0):
205 super().__init
__(self
.__class
__.layout(iotype
), name
=name
,
206 src_loc_at
=src_loc_at
+1)
208 self
._iotype
= iotype
210 class _IDBypassBlock(Elaboratable
):
211 """TAP subblock for the ID shift register"""
212 def __init__(self
, *, manufacturer_id
, part_number
, version
,
213 tdi
, capture
, shift
, update
, bypass
,
216 if (not isinstance(manufacturer_id
, Const
) and
217 len(manufacturer_id
) != 11):
218 raise ValueError("manufacturer_id has to be Const of length 11")
219 if not isinstance(part_number
, Const
) and len(manufacturer_id
) != 16:
220 raise ValueError("part_number has to be Const of length 16")
221 if not isinstance(version
, Const
) and len(version
) != 4:
222 raise ValueError("version has to be Const of length 4")
223 self
._id
= Cat(Const(1,1), manufacturer_id
, part_number
, version
)
225 self
.tdo
= Signal(name
=name
+"_tdo")
228 self
._capture
= capture
230 self
._update
= update
231 self
._bypass
= bypass
233 def elaborate(self
, platform
):
236 sr
= Signal(32, reset_less
=True, name
=self
.name
+"_sr")
238 # Local signals for the module
247 _capture
.eq(self
._capture
),
248 _shift
.eq(self
._shift
),
249 _update
.eq(self
._update
),
250 _bypass
.eq(self
._bypass
),
255 m
.d
.posjtag
+= sr
.eq(self
._id
)
258 m
.d
.posjtag
+= sr
[0].eq(_tdi
)
260 m
.d
.posjtag
+= sr
.eq(Cat(sr
[1:], _tdi
))
265 class ShiftReg(Record
):
266 """Object with interface for extra shift registers on a TAP.
271 cmds : int, default=1
272 The number of corresponding JTAG instructions
274 This object is normally only allocated and returned from ``TAP.add_shiftreg``
275 It is a Record subclass.
279 i: length=sr_length, FANIN
280 The input data sampled during capture state of the TAP
281 ie: length=cmds, FANOUT
282 Indicates that data is to be sampled by the JTAG TAP and
283 should be held stable. The bit indicates the corresponding
284 instruction for which data is asked.
285 This signal is kept high for a whole JTAG TAP clock cycle
286 and may thus be kept higher for more than one clock cycle
287 on the domain where ShiftReg is used.
288 The JTAG protocol does not allow insertion of wait states
289 so data need to be provided before ie goes down. The speed
290 of the response will determine the max. frequency for the
292 o: length=sr_length, FANOUT
293 The value of the shift register.
294 oe: length=cmds, FANOUT
295 Indicates that output is stable and can be sampled downstream because
296 JTAG TAP is in the Update state. The bit indicates the corresponding
297 instruction. The bit is only kept high for one clock cycle.
299 def __init__(self
, *, sr_length
, cmds
=1, name
=None, src_loc_at
=0):
301 ("i", sr_length
, Direction
.FANIN
),
302 ("ie", cmds
, Direction
.FANOUT
),
303 ("o", sr_length
, Direction
.FANOUT
),
304 ("oe", cmds
, Direction
.FANOUT
),
306 super().__init
__(layout
, name
=name
, src_loc_at
=src_loc_at
+1)
308 class TAP(Elaboratable
):
310 def __init__(self
, *, with_reset
=False, ir_width
=None,
311 manufacturer_id
=Const(0b10001111111, 11),
312 part_number
=Const(1, 16),
314 name
=None, src_loc_at
=0):
315 assert((ir_width
is None) or (isinstance(ir_width
, int) and
317 assert(len(version
) == 4)
320 name
= get_var_name(depth
=src_loc_at
+2, default
="TAP")
322 self
.bus
= Interface(with_reset
=with_reset
, name
=self
.name
+"_bus",
323 src_loc_at
=src_loc_at
+1)
327 self
._ir
_width
= ir_width
328 self
._manufacturer
_id
= manufacturer_id
329 self
._part
_number
= part_number
330 self
._version
= version
332 self
._ircodes
= [0, 1, 2] # Already taken codes, all ones added at end
339 def elaborate(self
, platform
):
342 # Determine ir_width if not fixed.
343 ir_max
= max(self
._ircodes
) + 1 # One extra code needed with all ones
344 ir_width
= len("{:b}".format(ir_max
))
345 if self
._ir
_width
is not None:
346 assert self
._ir
_width
>= ir_width
, "Specified JTAG IR width " \
347 "not big enough for allocated shiift registers"
348 ir_width
= self
._ir
_width
350 # TODO: Make commands numbers configurable
356 cmd_bypass
= 2**ir_width
- 1 # All ones
358 m
.submodules
._fsm
= fsm
= _FSM(bus
=self
.bus
)
359 m
.domains
.posjtag
= fsm
.posjtag
360 m
.domains
.negjtag
= fsm
.negjtag
364 m
.submodules
._irblock
= irblock
= _IRBlock(
365 ir_width
=ir_width
, cmd_idcode
=cmd_idcode
, tdi
=self
.bus
.tdi
,
366 capture
=(fsm
.isir
& fsm
.capture
),
367 shift
=(fsm
.isir
& fsm
.shift
),
368 update
=(fsm
.isir
& fsm
.update
),
369 name
=self
.name
+"_ir",
376 m
.d
.comb
+= select_id
.eq(fsm
.isdr
&
377 ((ir
== cmd_idcode
) |
(ir
== cmd_bypass
)))
378 m
.d
.comb
+= id_bypass
.eq(ir
== cmd_bypass
)
379 m
.submodules
._idblock
= idblock
= _IDBypassBlock(
380 manufacturer_id
=self
._manufacturer
_id
,
381 part_number
=self
._part
_number
,
382 version
=self
._version
, tdi
=self
.bus
.tdi
,
383 capture
=(select_id
& fsm
.capture
),
384 shift
=(select_id
& fsm
.shift
),
385 update
=(select_id
& fsm
.update
),
387 name
=self
.name
+"_id",
390 # IO (Boundary scan) block
391 io_capture
= Signal()
395 io_bd2core
= Signal()
396 sample
= (ir
== cmd_extest
) |
(ir
== cmd_sample
)
397 preload
= (ir
== cmd_preload
)
398 select_io
= fsm
.isdr
& (sample | preload
)
400 io_capture
.eq(sample
& fsm
.capture
), # Don't capture if not sample
402 io_shift
.eq(select_io
& fsm
.shift
),
403 io_update
.eq(select_io
& fsm
.update
),
404 io_bd2io
.eq(ir
== cmd_extest
),
405 io_bd2core
.eq(ir
== cmd_intest
),
407 io_tdo
= self
._elaborate
_ios
(
409 capture
=io_capture
, shift
=io_shift
, update
=io_update
,
410 bd2io
=io_bd2io
, bd2core
=io_bd2core
,
413 # chain tdo: select as appropriate, to go into into shiftregs
414 tdo
= Signal(name
=self
.name
+"_tdo")
415 with m
.If(select_ir
):
416 m
.d
.comb
+= tdo
.eq(irblock
.tdo
)
417 with m
.Elif(select_id
):
418 m
.d
.comb
+= tdo
.eq(idblock
.tdo
)
419 if io_tdo
is not None:
420 with m
.Elif(select_io
):
421 m
.d
.comb
+= tdo
.eq(io_tdo
)
424 self
._elaborate
_shiftregs
(
425 m
, capture
=fsm
.capture
, shift
=fsm
.shift
, update
=fsm
.update
,
426 ir
=irblock
.ir
, tdo_jtag
=tdo
430 self
._elaborate
_wishbones
(m
)
432 # DMI (Debug Memory Interface)
433 self
._elaborate
_dmis
(m
)
437 def add_dmi(self
, *, ircodes
, address_width
=8, data_width
=64,
438 domain
="sync", name
=None):
439 """Add a DMI interface
441 * writing to DMIADDR will automatically trigger a DMI READ.
442 the DMI address does not alter (so writes can be done at that addr)
443 * reading from DMIREAD triggers a DMI READ at the current DMI addr
444 the address is automatically incremented by 1 after.
445 * writing to DMIWRITE triggers a DMI WRITE at the current DMI addr
446 the address is automatically incremented by 1 after.
450 ircodes: sequence of three integer for the JTAG IR codes;
451 they represent resp. DMIADDR, DMIREAD and DMIWRITE.
452 First code has a shift register of length 'address_width',
453 the two other codes share a shift register of length
456 address_width: width of the address
457 data_width: width of the data
460 dmi: soc.debug.dmi.DMIInterface
463 if len(ircodes
) != 3:
464 raise ValueError("3 IR Codes have to be provided")
467 name
= "dmi" + str(len(self
._dmis
))
469 # add 2 shift registers: one for addr, one for data.
470 sr_addr
= self
.add_shiftreg(ircode
=ircodes
[0], length
=address_width
,
471 domain
=domain
, name
=name
+"_addrsr")
472 sr_data
= self
.add_shiftreg(ircode
=ircodes
[1:], length
=data_width
,
473 domain
=domain
, name
=name
+"_datasr")
475 dmi
= DMIInterface(name
=name
)
476 self
._dmis
.append((sr_addr
, sr_data
, dmi
, domain
))
480 def _elaborate_dmis(self
, m
):
481 for sr_addr
, sr_data
, dmi
, domain
in self
._dmis
:
483 m
.d
.comb
+= sr_addr
.i
.eq(dmi
.addr_i
)
485 with m
.FSM(domain
=domain
) as ds
:
487 # detect mode based on whether jtag addr or data read/written
488 with m
.State("IDLE"):
489 with m
.If(sr_addr
.oe
): # DMIADDR code
490 cd
+= dmi
.addr_i
.eq(sr_addr
.o
)
492 with m
.Elif(sr_data
.oe
[0]): # DMIREAD code
494 cd
+= dmi
.addr_i
.eq(dmi
.addr_i
+ 1)
496 with m
.Elif(sr_data
.oe
[1]): # DMIWRITE code
497 cd
+= dmi
.din
.eq(sr_data
.o
)
500 # req_i raises for 1 clock
501 with m
.State("READ"):
505 with m
.State("READACK"):
506 with m
.If(dmi
.ack_o
):
507 # Store read data in sr_data.i hold till next read
508 cd
+= sr_data
.i
.eq(dmi
.dout
)
511 # req_i raises for 1 clock
512 with m
.State("WRRD"):
516 with m
.State("WRRDACK"):
517 with m
.If(dmi
.ack_o
):
518 cd
+= dmi
.addr_i
.eq(dmi
.addr_i
+ 1)
519 m
.next
= "READ" # for readwrite
521 # set DMI req and write-enable based on ongoing FSM states
523 dmi
.req_i
.eq(ds
.ongoing("READ") | ds
.ongoing("WRRD")),
524 dmi
.we_i
.eq(ds
.ongoing("WRRD")),
527 def add_io(self
, *, iotype
, name
=None, src_loc_at
=0):
528 """Add a io cell to the boundary scan chain
531 - iotype: :class:`IOType` enum.
537 name
= "ioconn" + str(len(self
._ios
))
539 ioconn
= IOConn(iotype
=iotype
, name
=name
, src_loc_at
=src_loc_at
+1)
540 self
._ios
.append(ioconn
)
543 def _elaborate_ios(self
, *, m
, capture
, shift
, update
, bd2io
, bd2core
):
544 length
= sum(IOConn
.lengths
[conn
._iotype
] for conn
in self
._ios
)
548 io_sr
= Signal(length
)
549 io_bd
= Signal(length
)
551 # Boundary scan "capture" mode. makes I/O status available via SR
555 for conn
in self
._ios
:
556 # in appropriate sequence: In/TriOut has pad.i,
557 # Out.InTriOut has everything, Out and TriOut have core.o
558 if conn
._iotype
in [IOType
.In
, IOType
.InTriOut
]:
559 iol
.append(conn
.pad
.i
)
560 if conn
._iotype
in [IOType
.Out
, IOType
.InTriOut
]:
561 iol
.append(conn
.core
.o
)
562 if conn
._iotype
in [IOType
.TriOut
, IOType
.InTriOut
]:
563 iol
.append(conn
.core
.oe
)
564 # length double-check
565 idx
+= IOConn
.lengths
[conn
._iotype
] # fails if wrong type
566 assert idx
== length
, "Internal error"
567 m
.d
.posjtag
+= io_sr
.eq(Cat(*iol
)) # assigns all io_sr in one hit
569 # "Shift" mode (sends out captured data on tdo, sets incoming from tdi)
571 m
.d
.posjtag
+= io_sr
.eq(Cat(self
.bus
.tdi
, io_sr
[:-1]))
575 m
.d
.negjtag
+= io_bd
.eq(io_sr
)
577 # sets up IO (pad<->core) or in testing mode depending on requested
578 # mode, via Muxes controlled by bd2core and bd2io
580 for conn
in self
._ios
:
581 if conn
._iotype
== IOType
.In
:
582 m
.d
.comb
+= conn
.core
.i
.eq(Mux(bd2core
, io_bd
[idx
], conn
.pad
.i
))
584 elif conn
._iotype
== IOType
.Out
:
585 m
.d
.comb
+= conn
.pad
.o
.eq(Mux(bd2io
, io_bd
[idx
], conn
.core
.o
))
587 elif conn
._iotype
== IOType
.TriOut
:
589 conn
.pad
.o
.eq(Mux(bd2io
, io_bd
[idx
], conn
.core
.o
)),
590 conn
.pad
.oe
.eq(Mux(bd2io
, io_bd
[idx
+1], conn
.core
.oe
)),
593 elif conn
._iotype
== IOType
.InTriOut
:
595 conn
.core
.i
.eq(Mux(bd2core
, io_bd
[idx
], conn
.pad
.i
)),
596 conn
.pad
.o
.eq(Mux(bd2io
, io_bd
[idx
+1], conn
.core
.o
)),
597 conn
.pad
.oe
.eq(Mux(bd2io
, io_bd
[idx
+2], conn
.core
.oe
)),
601 raise("Internal error")
602 assert idx
== length
, "Internal error"
606 def add_shiftreg(self
, *, ircode
, length
, domain
="sync", name
=None,
608 """Add a shift register to the JTAG interface
611 - ircode: code(s) for the IR; int or sequence of ints. In the latter
612 case this shiftreg is shared between different IR codes.
613 - length: the length of the shift register
614 - domain: the domain on which the signal will be used"""
620 ir_it
= ircodes
= (ircode
,)
621 for _ircode
in ir_it
:
622 if not isinstance(_ircode
, int) or _ircode
<= 0:
623 raise ValueError("IR code '{}' is not an int "
624 "greater than 0".format(_ircode
))
625 if _ircode
in self
._ircodes
:
626 raise ValueError("IR code '{}' already taken".format(_ircode
))
628 self
._ircodes
.extend(ircodes
)
631 name
= "sr{}".format(len(self
._srs
))
632 sr
= ShiftReg(sr_length
=length
, cmds
=len(ircodes
), name
=name
,
633 src_loc_at
=src_loc_at
+1)
634 self
._srs
.append((ircodes
, domain
, sr
))
638 def _elaborate_shiftregs(self
, m
, capture
, shift
, update
, ir
, tdo_jtag
):
639 # tdos is tuple of (tdo, tdo_en) for each shiftreg
641 for ircodes
, domain
, sr
in self
._srs
:
642 reg
= Signal(len(sr
.o
), name
=sr
.name
+"_reg")
643 m
.d
.comb
+= sr
.o
.eq(reg
)
645 isir
= Signal(len(ircodes
), name
=sr
.name
+"_isir")
646 sr_capture
= Signal(name
=sr
.name
+"_capture")
647 sr_shift
= Signal(name
=sr
.name
+"_shift")
648 sr_update
= Signal(name
=sr
.name
+"_update")
650 isir
.eq(Cat(ir
== ircode
for ircode
in ircodes
)),
651 sr_capture
.eq((isir
!= 0) & capture
),
652 sr_shift
.eq((isir
!= 0) & shift
),
653 sr_update
.eq((isir
!= 0) & update
),
656 # update signal is on the JTAG clockdomain, sr.oe is on `domain`
657 # clockdomain latch update in `domain` clockdomain and see when
658 # it has falling edge.
659 # At that edge put isir in sr.oe for one `domain` clockdomain
660 update_core
= Signal(name
=sr
.name
+"_update_core")
661 update_core_prev
= Signal(name
=sr
.name
+"_update_core_prev")
663 update_core
.eq(sr_update
), # This is CDC from JTAG domain
665 update_core_prev
.eq(update_core
)
667 with m
.If(update_core_prev
& ~update_core
):
668 # Falling edge of update
669 m
.d
[domain
] += sr
.oe
.eq(isir
)
671 m
.d
[domain
] += sr
.oe
.eq(0)
674 m
.d
.posjtag
+= reg
.eq(Cat(reg
[1:], self
.bus
.tdi
))
675 with m
.If(sr_capture
):
676 m
.d
.posjtag
+= reg
.eq(sr
.i
)
678 # tdo = reg[0], tdo_en = shift
679 tdos
.append((reg
[0], sr_shift
))
682 # Assign the right tdo to the bus tdo
683 for i
, (tdo
, tdo_en
) in enumerate(tdos
):
686 m
.d
.comb
+= self
.bus
.tdo
.eq(tdo
)
689 m
.d
.comb
+= self
.bus
.tdo
.eq(tdo
)
693 m
.d
.comb
+= self
.bus
.tdo
.eq(tdo_jtag
)
695 # Always connect tdo_jtag to
696 m
.d
.comb
+= self
.bus
.tdo
.eq(tdo_jtag
)
699 def add_wishbone(self
, *, ircodes
, address_width
, data_width
,
700 granularity
=None, domain
="sync", features
=None,
701 name
=None, src_loc_at
=0):
702 """Add a wishbone interface
704 In order to allow high JTAG clock speed, data will be cached.
705 This means that if data is output the value of the next address
706 will be read automatically.
710 ircodes: sequence of three integer for the JTAG IR codes;
711 they represent resp. WBADDR, WBREAD and WBREADWRITE. First code
712 has a shift register of length 'address_width', the two other codes
713 share a shift register of length data_width.
714 address_width: width of the address
715 data_width: width of the data
716 features: features required. defaults to stall, lock, err, rty
719 wb: nmigen_soc.wishbone.bus.Interface
720 The Wishbone interface, is pipelined and has stall field.
722 if len(ircodes
) != 3:
723 raise ValueError("3 IR Codes have to be provided")
726 features
={"stall", "lock", "err", "rty"}
728 name
= "wb" + str(len(self
._wbs
))
729 sr_addr
= self
.add_shiftreg(
730 ircode
=ircodes
[0], length
=address_width
, domain
=domain
,
733 sr_data
= self
.add_shiftreg(
734 ircode
=ircodes
[1:], length
=data_width
, domain
=domain
,
738 wb
= WishboneInterface(data_width
=data_width
, addr_width
=address_width
,
739 granularity
=granularity
, features
=features
,
740 name
=name
, src_loc_at
=src_loc_at
+1)
742 self
._wbs
.append((sr_addr
, sr_data
, wb
, domain
))
746 def _elaborate_wishbones(self
, m
):
747 for sr_addr
, sr_data
, wb
, domain
in self
._wbs
:
748 m
.d
.comb
+= sr_addr
.i
.eq(wb
.adr
)
750 if hasattr(wb
, "sel"):
752 m
.d
.comb
+= [s
.eq(1) for s
in wb
.sel
]
754 with m
.FSM(domain
=domain
) as fsm
:
755 with m
.State("IDLE"):
756 with m
.If(sr_addr
.oe
): # WBADDR code
757 m
.d
[domain
] += wb
.adr
.eq(sr_addr
.o
)
759 with m
.Elif(sr_data
.oe
[0]): # WBREAD code
761 m
.d
[domain
] += wb
.adr
.eq(wb
.adr
+ 1)
763 with m
.Elif(sr_data
.oe
[1]): # WBWRITE code
764 m
.d
[domain
] += wb
.dat_w
.eq(sr_data
.o
)
766 with m
.State("READ"):
767 if not hasattr(wb
, "stall"):
770 with m
.If(~wb
.stall
):
772 with m
.State("READACK"):
774 # Store read data in sr_data.i
775 # and keep it there til next read
776 m
.d
[domain
] += sr_data
.i
.eq(wb
.dat_r
)
778 with m
.State("WRITEREAD"):
779 if not hasattr(wb
, "stall"):
780 m
.next
= "WRITEREADACK"
782 with m
.If(~wb
.stall
):
783 m
.next
= "WRITEREADACK"
784 with m
.State("WRITEREADACK"):
786 m
.d
[domain
] += wb
.adr
.eq(wb
.adr
+ 1)
789 if hasattr(wb
, "stall"):
790 m
.d
.comb
+= wb
.stb
.eq(fsm
.ongoing("READ") |
791 fsm
.ongoing("WRITEREAD"))
793 # non-stall is single-cycle (litex), must assert stb
795 m
.d
.comb
+= wb
.stb
.eq(fsm
.ongoing("READ") |
796 fsm
.ongoing("WRITEREAD") |
797 fsm
.ongoing("READACK") |
798 fsm
.ongoing("WRITEREADACK"))
800 wb
.cyc
.eq(~fsm
.ongoing("IDLE")),
801 wb
.we
.eq(fsm
.ongoing("WRITEREAD")),