6d1bcf7de9144e0659f98c15429a28f2b4bc5236
3 not in any way intended for production use. this runs a FSM that:
5 * reads the Program Counter from StateRegs
6 * reads an instruction from a fixed-size Test Memory
7 * issues it to the Simple Core
8 * waits for it to complete
10 * does it all over again
12 the purpose of this module is to verify the functional correctness
13 of the Function Units in the absolute simplest and clearest possible
14 way, and to at provide something that can be further incrementally
18 from nmigen
import (Elaboratable
, Module
, Signal
, ClockSignal
, ResetSignal
,
19 ClockDomain
, DomainRenamer
, Mux
, Const
)
20 from nmigen
.cli
import rtlil
21 from nmigen
.cli
import main
24 from soc
.decoder
.power_decoder
import create_pdecode
25 from soc
.decoder
.power_decoder2
import PowerDecode2
, SVP64PrefixDecoder
26 from soc
.decoder
.decode2execute1
import IssuerDecode2ToOperand
27 from soc
.decoder
.decode2execute1
import Data
28 from soc
.experiment
.testmem
import TestMemory
# test only for instructions
29 from soc
.regfile
.regfiles
import StateRegs
, FastRegs
30 from soc
.simple
.core
import NonProductionCore
31 from soc
.config
.test
.test_loadstore
import TestMemPspec
32 from soc
.config
.ifetch
import ConfigFetchUnit
33 from soc
.decoder
.power_enums
import MicrOp
34 from soc
.debug
.dmi
import CoreDebug
, DMIInterface
35 from soc
.debug
.jtag
import JTAG
36 from soc
.config
.pinouts
import get_pinspecs
37 from soc
.config
.state
import CoreState
38 from soc
.interrupts
.xics
import XICS_ICP
, XICS_ICS
39 from soc
.bus
.simple_gpio
import SimpleGPIO
40 from soc
.bus
.SPBlock512W64B8W
import SPBlock512W64B8W
41 from soc
.clock
.select
import ClockSelect
42 from soc
.clock
.dummypll
import DummyPLL
43 from soc
.sv
.svstate
import SVSTATERec
46 from nmutil
.util
import rising_edge
48 def get_insn(f_instr_o
, pc
):
49 if f_instr_o
.width
== 32:
52 # 64-bit: bit 2 of pc decides which word to select
53 return f_instr_o
.word_select(pc
[2], 32)
56 class TestIssuerInternal(Elaboratable
):
57 """TestIssuer - reads instructions from TestMemory and issues them
59 efficiency and speed is not the main goal here: functional correctness is.
61 def __init__(self
, pspec
):
63 # JTAG interface. add this right at the start because if it's
64 # added it *modifies* the pspec, by adding enable/disable signals
65 # for parts of the rest of the core
66 self
.jtag_en
= hasattr(pspec
, "debug") and pspec
.debug
== 'jtag'
68 subset
= {'uart', 'mtwi', 'eint', 'gpio', 'mspi0', 'mspi1',
70 self
.jtag
= JTAG(get_pinspecs(subset
=subset
))
71 # add signals to pspec to enable/disable icache and dcache
72 # (or data and intstruction wishbone if icache/dcache not included)
73 # https://bugs.libre-soc.org/show_bug.cgi?id=520
74 # TODO: do we actually care if these are not domain-synchronised?
75 # honestly probably not.
76 pspec
.wb_icache_en
= self
.jtag
.wb_icache_en
77 pspec
.wb_dcache_en
= self
.jtag
.wb_dcache_en
78 self
.wb_sram_en
= self
.jtag
.wb_sram_en
80 self
.wb_sram_en
= Const(1)
83 self
.sram4x4k
= (hasattr(pspec
, "sram4x4kblock") and
84 pspec
.sram4x4kblock
== True)
88 self
.sram4k
.append(SPBlock512W64B8W(name
="sram4k_%d" % i
))
90 # add interrupt controller?
91 self
.xics
= hasattr(pspec
, "xics") and pspec
.xics
== True
93 self
.xics_icp
= XICS_ICP()
94 self
.xics_ics
= XICS_ICS()
95 self
.int_level_i
= self
.xics_ics
.int_level_i
97 # add GPIO peripheral?
98 self
.gpio
= hasattr(pspec
, "gpio") and pspec
.gpio
== True
100 self
.simple_gpio
= SimpleGPIO()
101 self
.gpio_o
= self
.simple_gpio
.gpio_o
103 # main instruction core25
104 self
.core
= core
= NonProductionCore(pspec
)
106 # instruction decoder. goes into Trap Record
107 pdecode
= create_pdecode()
108 self
.cur_state
= CoreState("cur") # current state (MSR/PC/EINT/SVSTATE)
109 self
.pdecode2
= PowerDecode2(pdecode
, state
=self
.cur_state
,
110 opkls
=IssuerDecode2ToOperand
)
111 self
.svp64
= SVP64PrefixDecoder() # for decoding SVP64 prefix
113 # Test Instruction memory
114 self
.imem
= ConfigFetchUnit(pspec
).fu
115 # one-row cache of instruction read
116 self
.iline
= Signal(64) # one instruction line
117 self
.iprev_adr
= Signal(64) # previous address: if different, do read
120 self
.dbg
= CoreDebug()
122 # instruction go/monitor
123 self
.pc_o
= Signal(64, reset_less
=True)
124 self
.pc_i
= Data(64, "pc_i") # set "ok" to indicate "please change me"
125 self
.core_bigendian_i
= Signal()
126 self
.busy_o
= Signal(reset_less
=True)
127 self
.memerr_o
= Signal(reset_less
=True)
129 # STATE regfile read /write ports for PC, MSR, SVSTATE
130 staterf
= self
.core
.regs
.rf
['state']
131 self
.state_r_pc
= staterf
.r_ports
['cia'] # PC rd
132 self
.state_w_pc
= staterf
.w_ports
['d_wr1'] # PC wr
133 self
.state_r_msr
= staterf
.r_ports
['msr'] # MSR rd
134 self
.state_r_sv
= staterf
.r_ports
['sv'] # SVSTATE rd
135 self
.state_w_sv
= staterf
.w_ports
['sv'] # SVSTATE wr
137 # DMI interface access
138 intrf
= self
.core
.regs
.rf
['int']
139 crrf
= self
.core
.regs
.rf
['cr']
140 xerrf
= self
.core
.regs
.rf
['xer']
141 self
.int_r
= intrf
.r_ports
['dmi'] # INT read
142 self
.cr_r
= crrf
.r_ports
['full_cr_dbg'] # CR read
143 self
.xer_r
= xerrf
.r_ports
['full_xer'] # XER read
145 # hack method of keeping an eye on whether branch/trap set the PC
146 self
.state_nia
= self
.core
.regs
.rf
['state'].w_ports
['nia']
147 self
.state_nia
.wen
.name
= 'state_nia_wen'
149 def fetch_fsm(self
, m
, core
, dbg
, pc
, pc_changed
, sv_changed
, insn_done
,
151 fetch_pc_ready_o
, fetch_pc_valid_i
,
152 fetch_insn_valid_o
, fetch_insn_ready_i
):
154 this FSM performs fetch of raw instruction data, partial-decodes
155 it 32-bit at a time to detect SVP64 prefixes, and will optionally
156 read a 2nd 32-bit quantity if that occurs.
160 pdecode2
= self
.pdecode2
163 # latches copy of raw fetched instruction
164 fetch_insn_o
= Signal(32, reset_less
=True)
165 dec_opcode_i
= pdecode2
.dec
.raw_opcode_in
# raw opcode
166 sync
+= dec_opcode_i
.eq(fetch_insn_o
) # actual opcode
168 msr_read
= Signal(reset
=1)
169 sv_read
= Signal(reset
=1)
171 # address of the next instruction, in the absence of a branch
172 # depends on the instruction size
173 nia
= Signal(64, reset_less
=True)
175 with m
.FSM(name
='fetch_fsm'):
178 with m
.State("IDLE"):
179 with m
.If(~dbg
.core_stop_o
& ~core_rst
):
180 comb
+= fetch_pc_ready_o
.eq(1)
181 with m
.If(fetch_pc_valid_i
):
182 # instruction allowed to go: start by reading the PC
183 # capture the PC and also drop it into Insn Memory
184 # we have joined a pair of combinatorial memory
185 # lookups together. this is Generally Bad.
186 comb
+= self
.imem
.a_pc_i
.eq(pc
)
187 comb
+= self
.imem
.a_valid_i
.eq(1)
188 comb
+= self
.imem
.f_valid_i
.eq(1)
189 sync
+= cur_state
.pc
.eq(pc
)
191 # initiate read of MSR/SVSTATE. arrives one clock later
192 comb
+= self
.state_r_msr
.ren
.eq(1 << StateRegs
.MSR
)
193 comb
+= self
.state_r_sv
.ren
.eq(1 << StateRegs
.SVSTATE
)
194 sync
+= msr_read
.eq(0)
195 sync
+= sv_read
.eq(0)
197 m
.next
= "INSN_READ" # move to "wait for bus" phase
199 comb
+= core
.core_stopped_i
.eq(1)
200 comb
+= dbg
.core_stopped_i
.eq(1)
202 # dummy pause to find out why simulation is not keeping up
203 with m
.State("INSN_READ"):
204 # one cycle later, msr/sv read arrives. valid only once.
205 with m
.If(~msr_read
):
206 sync
+= msr_read
.eq(1) # yeah don't read it again
207 sync
+= cur_state
.msr
.eq(self
.state_r_msr
.data_o
)
209 sync
+= sv_read
.eq(1) # yeah don't read it again
210 sync
+= cur_state
.svstate
.eq(self
.state_r_sv
.data_o
)
211 with m
.If(self
.imem
.f_busy_o
): # zzz...
212 # busy: stay in wait-read
213 comb
+= self
.imem
.a_valid_i
.eq(1)
214 comb
+= self
.imem
.f_valid_i
.eq(1)
216 # not busy: instruction fetched
217 insn
= get_insn(self
.imem
.f_instr_o
, cur_state
.pc
)
218 # decode the SVP64 prefix, if any
219 comb
+= svp64
.raw_opcode_in
.eq(insn
)
220 comb
+= svp64
.bigendian
.eq(self
.core_bigendian_i
)
221 # pass the decoded prefix (if any) to PowerDecoder2
222 sync
+= pdecode2
.sv_rm
.eq(svp64
.svp64_rm
)
223 # calculate the address of the following instruction
224 insn_size
= Mux(svp64
.is_svp64_mode
, 8, 4)
225 sync
+= nia
.eq(cur_state
.pc
+ insn_size
)
226 with m
.If(~svp64
.is_svp64_mode
):
227 # with no prefix, store the instruction
228 # and hand it directly to the next FSM
229 comb
+= fetch_insn_o
.eq(insn
)
230 m
.next
= "INSN_READY"
232 # fetch the rest of the instruction from memory
233 comb
+= self
.imem
.a_pc_i
.eq(cur_state
.pc
+ 4)
234 comb
+= self
.imem
.a_valid_i
.eq(1)
235 comb
+= self
.imem
.f_valid_i
.eq(1)
236 m
.next
= "INSN_READ2"
238 with m
.State("INSN_READ2"):
239 with m
.If(self
.imem
.f_busy_o
): # zzz...
240 # busy: stay in wait-read
241 comb
+= self
.imem
.a_valid_i
.eq(1)
242 comb
+= self
.imem
.f_valid_i
.eq(1)
244 # not busy: instruction fetched
245 insn
= get_insn(self
.imem
.f_instr_o
, cur_state
.pc
+4)
246 comb
+= fetch_insn_o
.eq(insn
)
247 m
.next
= "INSN_READY"
249 with m
.State("INSN_READY"):
250 # hand over the instruction, to be decoded
251 comb
+= fetch_insn_valid_o
.eq(1)
252 with m
.If(fetch_insn_ready_i
):
255 # code-morph: moving the actual PC-setting out of "execute"
256 # so that it's easier to move this into an "issue" FSM.
258 # ok here we are not reading the branch unit. TODO
259 # this just blithely overwrites whatever pipeline
261 core_busy_o
= core
.busy_o
# core is busy
262 with m
.If(insn_done
& (~pc_changed
) & (~core_busy_o
)):
263 comb
+= self
.state_w_pc
.wen
.eq(1<<StateRegs
.PC
)
264 comb
+= self
.state_w_pc
.data_i
.eq(nia
)
266 def issue_fsm(self
, m
, core
, cur_state
,
267 fetch_pc_ready_o
, fetch_pc_valid_i
,
268 fetch_insn_valid_o
, fetch_insn_ready_i
,
269 exec_insn_valid_i
, exec_insn_ready_o
,
270 exec_pc_valid_o
, exec_pc_ready_i
):
273 decode / issue FSM. this interacts with the "fetch" FSM
274 through fetch_insn_ready/valid (incoming) and fetch_pc_ready/valid
275 (outgoing). also interacts with the "execute" FSM
276 through exec_insn_ready/valid (outgoing) and exec_pc_ready/valid
278 SVP64 RM prefixes have already been set up by the
279 "fetch" phase, so execute is fairly straightforward.
284 pdecode2
= self
.pdecode2
287 dec_opcode_i
= pdecode2
.dec
.raw_opcode_in
# raw opcode
289 with m
.FSM(name
="issue_fsm"):
291 # go fetch the instruction at the current PC
292 # at this point, there is no instruction running, that
293 # could inadvertently update the PC.
294 with m
.State("INSN_FETCH"):
295 # TODO: update PC here, before fetch
296 comb
+= fetch_pc_valid_i
.eq(1)
297 with m
.If(fetch_pc_ready_o
):
300 # decode the instruction when it arrives
301 with m
.State("INSN_WAIT"):
302 comb
+= fetch_insn_ready_i
.eq(1)
303 with m
.If(fetch_insn_valid_o
):
304 # decode the instruction
305 sync
+= core
.e
.eq(pdecode2
.e
)
306 sync
+= core
.state
.eq(cur_state
)
307 sync
+= core
.raw_insn_i
.eq(dec_opcode_i
)
308 sync
+= core
.bigendian_i
.eq(self
.core_bigendian_i
)
309 # TODO: loop into INSN_FETCH if it's a vector instruction
310 # and VL == 0. this because VL==0 is a for-loop
311 # from 0 to 0 i.e. always, always a NOP.
312 m
.next
= "INSN_EXECUTE" # move to "execute"
314 with m
.State("INSN_EXECUTE"):
315 comb
+= exec_insn_valid_i
.eq(1)
316 with m
.If(exec_insn_ready_o
):
317 m
.next
= "EXECUTE_WAIT"
319 with m
.State("EXECUTE_WAIT"):
320 comb
+= exec_pc_ready_i
.eq(1)
321 with m
.If(exec_pc_valid_o
):
322 # TODO: update SRCSTEP here
323 # TODO: loop into INSN_EXECUTE if it's a vector instruction
324 # and SRCSTEP != VL-1 and PowerDecoder.no_out_vec
326 # unless PC / SVSTATE was modified, in that case do
327 # go back to INSN_FETCH.
328 m
.next
= "INSN_FETCH"
330 def execute_fsm(self
, m
, core
, insn_done
, pc_changed
, sv_changed
,
331 exec_insn_valid_i
, exec_insn_ready_o
,
332 exec_pc_valid_o
, exec_pc_ready_i
):
335 execute FSM. this interacts with the "issue" FSM
336 through exec_insn_ready/valid (incoming) and exec_pc_ready/valid
337 (outgoing). SVP64 RM prefixes have already been set up by the
338 "issue" phase, so execute is fairly straightforward.
343 pdecode2
= self
.pdecode2
347 core_busy_o
= core
.busy_o
# core is busy
348 core_ivalid_i
= core
.ivalid_i
# instruction is valid
349 core_issue_i
= core
.issue_i
# instruction is issued
350 insn_type
= core
.e
.do
.insn_type
# instruction MicroOp type
352 with m
.FSM(name
="exec_fsm"):
354 # waiting for instruction bus (stays there until not busy)
355 with m
.State("INSN_START"):
356 comb
+= exec_insn_ready_o
.eq(1)
357 with m
.If(exec_insn_valid_i
):
358 comb
+= core_ivalid_i
.eq(1) # instruction is valid
359 comb
+= core_issue_i
.eq(1) # and issued
360 m
.next
= "INSN_ACTIVE" # move to "wait completion"
362 # instruction started: must wait till it finishes
363 with m
.State("INSN_ACTIVE"):
364 with m
.If(insn_type
!= MicrOp
.OP_NOP
):
365 comb
+= core_ivalid_i
.eq(1) # instruction is valid
366 # note changes to PC and SVSTATE
367 with m
.If(self
.state_nia
.wen
& (1<<StateRegs
.SVSTATE
)):
368 sync
+= sv_changed
.eq(1)
369 with m
.If(self
.state_nia
.wen
& (1<<StateRegs
.PC
)):
370 sync
+= pc_changed
.eq(1)
371 with m
.If(~core_busy_o
): # instruction done!
372 comb
+= insn_done
.eq(1)
374 sync
+= core
.raw_insn_i
.eq(0)
375 sync
+= core
.bigendian_i
.eq(0)
376 sync
+= sv_changed
.eq(0)
377 sync
+= pc_changed
.eq(0)
378 comb
+= exec_pc_valid_o
.eq(1)
379 with m
.If(exec_pc_ready_i
):
380 m
.next
= "INSN_START" # back to fetch
382 def elaborate(self
, platform
):
384 comb
, sync
= m
.d
.comb
, m
.d
.sync
386 m
.submodules
.core
= core
= DomainRenamer("coresync")(self
.core
)
387 m
.submodules
.imem
= imem
= self
.imem
388 m
.submodules
.dbg
= dbg
= self
.dbg
390 m
.submodules
.jtag
= jtag
= self
.jtag
391 # TODO: UART2GDB mux, here, from external pin
392 # see https://bugs.libre-soc.org/show_bug.cgi?id=499
393 sync
+= dbg
.dmi
.connect_to(jtag
.dmi
)
395 cur_state
= self
.cur_state
397 # 4x 4k SRAM blocks. these simply "exist", they get routed in litex
399 for i
, sram
in enumerate(self
.sram4k
):
400 m
.submodules
["sram4k_%d" % i
] = sram
401 comb
+= sram
.enable
.eq(self
.wb_sram_en
)
403 # XICS interrupt handler
405 m
.submodules
.xics_icp
= icp
= self
.xics_icp
406 m
.submodules
.xics_ics
= ics
= self
.xics_ics
407 comb
+= icp
.ics_i
.eq(ics
.icp_o
) # connect ICS to ICP
408 sync
+= cur_state
.eint
.eq(icp
.core_irq_o
) # connect ICP to core
410 # GPIO test peripheral
412 m
.submodules
.simple_gpio
= simple_gpio
= self
.simple_gpio
414 # connect one GPIO output to ICS bit 15 (like in microwatt soc.vhdl)
415 # XXX causes litex ECP5 test to get wrong idea about input and output
416 # (but works with verilator sim *sigh*)
417 #if self.gpio and self.xics:
418 # comb += self.int_level_i[15].eq(simple_gpio.gpio_o[0])
420 # instruction decoder
421 pdecode
= create_pdecode()
422 m
.submodules
.dec2
= pdecode2
= self
.pdecode2
423 m
.submodules
.svp64
= svp64
= self
.svp64
426 dmi
, d_reg
, d_cr
, d_xer
, = dbg
.dmi
, dbg
.d_gpr
, dbg
.d_cr
, dbg
.d_xer
427 intrf
= self
.core
.regs
.rf
['int']
429 # clock delay power-on reset
430 cd_por
= ClockDomain(reset_less
=True)
431 cd_sync
= ClockDomain()
432 core_sync
= ClockDomain("coresync")
433 m
.domains
+= cd_por
, cd_sync
, core_sync
435 ti_rst
= Signal(reset_less
=True)
436 delay
= Signal(range(4), reset
=3)
437 with m
.If(delay
!= 0):
438 m
.d
.por
+= delay
.eq(delay
- 1)
439 comb
+= cd_por
.clk
.eq(ClockSignal())
441 # power-on reset delay
442 core_rst
= ResetSignal("coresync")
443 comb
+= ti_rst
.eq(delay
!= 0 | dbg
.core_rst_o |
ResetSignal())
444 comb
+= core_rst
.eq(ti_rst
)
446 # busy/halted signals from core
447 comb
+= self
.busy_o
.eq(core
.busy_o
)
448 comb
+= pdecode2
.dec
.bigendian
.eq(self
.core_bigendian_i
)
450 # temporary hack: says "go" immediately for both address gen and ST
452 ldst
= core
.fus
.fus
['ldst0']
453 st_go_edge
= rising_edge(m
, ldst
.st
.rel_o
)
454 m
.d
.comb
+= ldst
.ad
.go_i
.eq(ldst
.ad
.rel_o
) # link addr-go direct to rel
455 m
.d
.comb
+= ldst
.st
.go_i
.eq(st_go_edge
) # link store-go to rising rel
457 # PC and instruction from I-Memory
458 comb
+= self
.pc_o
.eq(cur_state
.pc
)
459 pc_changed
= Signal() # note write to PC
460 sv_changed
= Signal() # note write to SVSTATE
461 insn_done
= Signal() # fires just once
464 pc
= Signal(64, reset_less
=True)
465 pc_ok_delay
= Signal()
466 sync
+= pc_ok_delay
.eq(~self
.pc_i
.ok
)
467 with m
.If(self
.pc_i
.ok
):
468 # incoming override (start from pc_i)
469 comb
+= pc
.eq(self
.pc_i
.data
)
471 # otherwise read StateRegs regfile for PC...
472 comb
+= self
.state_r_pc
.ren
.eq(1<<StateRegs
.PC
)
473 # ... but on a 1-clock delay
474 with m
.If(pc_ok_delay
):
475 comb
+= pc
.eq(self
.state_r_pc
.data_o
)
477 # don't write pc every cycle
478 comb
+= self
.state_w_pc
.wen
.eq(0)
479 comb
+= self
.state_w_pc
.data_i
.eq(0)
481 # don't read msr or svstate every cycle
482 comb
+= self
.state_r_sv
.ren
.eq(0)
483 comb
+= self
.state_r_msr
.ren
.eq(0)
485 # connect up debug signals
486 # TODO comb += core.icache_rst_i.eq(dbg.icache_rst_o)
487 comb
+= dbg
.terminate_i
.eq(core
.core_terminate_o
)
488 comb
+= dbg
.state
.pc
.eq(pc
)
489 #comb += dbg.state.pc.eq(cur_state.pc)
490 comb
+= dbg
.state
.msr
.eq(cur_state
.msr
)
492 # there are *TWO* FSMs, one fetch (32/64-bit) one decode/execute.
493 # these are the handshake signals between fetch and decode/execute
495 # fetch FSM can run as soon as the PC is valid
496 fetch_pc_valid_i
= Signal() # Execute tells Fetch "start next read"
497 fetch_pc_ready_o
= Signal() # Fetch Tells SVSTATE "proceed"
499 # fetch FSM hands over the instruction to be decoded / issued
500 fetch_insn_valid_o
= Signal()
501 fetch_insn_ready_i
= Signal()
503 # issue FSM delivers the instruction to the be executed
504 exec_insn_valid_i
= Signal()
505 exec_insn_ready_o
= Signal()
507 # execute FSM, hands over the PC/SVSTATE back to the issue FSM
508 exec_pc_valid_o
= Signal()
509 exec_pc_ready_i
= Signal()
511 # actually use a nmigen FSM for the first time (w00t)
512 # this FSM is perhaps unusual in that it detects conditions
513 # then "holds" information, combinatorially, for the core
514 # (as opposed to using sync - which would be on a clock's delay)
515 # this includes the actual opcode, valid flags and so on.
517 self
.fetch_fsm(m
, core
, dbg
, pc
, pc_changed
, sv_changed
, insn_done
,
519 fetch_pc_ready_o
, fetch_pc_valid_i
,
520 fetch_insn_valid_o
, fetch_insn_ready_i
)
522 # TODO: an SVSTATE-based for-loop FSM that goes in between
523 # fetch pc/insn ready/valid and advances SVSTATE.srcstep
524 # until it reaches VL-1 or PowerDecoder2.no_out_vec is True.
525 self
.issue_fsm(m
, core
, cur_state
,
526 fetch_pc_ready_o
, fetch_pc_valid_i
,
527 fetch_insn_valid_o
, fetch_insn_ready_i
,
528 exec_insn_valid_i
, exec_insn_ready_o
,
529 exec_pc_ready_i
, exec_pc_valid_o
)
531 self
.execute_fsm(m
, core
, insn_done
, pc_changed
, sv_changed
,
532 exec_insn_valid_i
, exec_insn_ready_o
,
533 exec_pc_ready_i
, exec_pc_valid_o
)
535 # for updating svstate (things like srcstep etc.)
536 update_svstate
= Signal() # TODO: move this somewhere above
537 new_svstate
= SVSTATERec("new_svstate") # and move this as well
538 # check if svstate needs updating: if so, write it to State Regfile
539 with m
.If(update_svstate
):
540 comb
+= self
.state_w_sv
.wen
.eq(1<<StateRegs
.SVSTATE
)
541 comb
+= self
.state_w_sv
.data_i
.eq(new_svstate
)
543 # this bit doesn't have to be in the FSM: connect up to read
544 # regfiles on demand from DMI
545 with m
.If(d_reg
.req
): # request for regfile access being made
546 # TODO: error-check this
547 # XXX should this be combinatorial? sync better?
549 comb
+= self
.int_r
.ren
.eq(1<<d_reg
.addr
)
551 comb
+= self
.int_r
.addr
.eq(d_reg
.addr
)
552 comb
+= self
.int_r
.ren
.eq(1)
553 d_reg_delay
= Signal()
554 sync
+= d_reg_delay
.eq(d_reg
.req
)
555 with m
.If(d_reg_delay
):
556 # data arrives one clock later
557 comb
+= d_reg
.data
.eq(self
.int_r
.data_o
)
558 comb
+= d_reg
.ack
.eq(1)
560 # sigh same thing for CR debug
561 with m
.If(d_cr
.req
): # request for regfile access being made
562 comb
+= self
.cr_r
.ren
.eq(0b11111111) # enable all
563 d_cr_delay
= Signal()
564 sync
+= d_cr_delay
.eq(d_cr
.req
)
565 with m
.If(d_cr_delay
):
566 # data arrives one clock later
567 comb
+= d_cr
.data
.eq(self
.cr_r
.data_o
)
568 comb
+= d_cr
.ack
.eq(1)
571 with m
.If(d_xer
.req
): # request for regfile access being made
572 comb
+= self
.xer_r
.ren
.eq(0b111111) # enable all
573 d_xer_delay
= Signal()
574 sync
+= d_xer_delay
.eq(d_xer
.req
)
575 with m
.If(d_xer_delay
):
576 # data arrives one clock later
577 comb
+= d_xer
.data
.eq(self
.xer_r
.data_o
)
578 comb
+= d_xer
.ack
.eq(1)
580 # DEC and TB inc/dec FSM. copy of DEC is put into CoreState,
581 # (which uses that in PowerDecoder2 to raise 0x900 exception)
582 self
.tb_dec_fsm(m
, cur_state
.dec
)
586 def tb_dec_fsm(self
, m
, spr_dec
):
589 this is a FSM for updating either dec or tb. it runs alternately
590 DEC, TB, DEC, TB. note that SPR pipeline could have written a new
591 value to DEC, however the regfile has "passthrough" on it so this
594 see v3.0B p1097-1099 for Timeer Resource and p1065 and p1076
597 comb
, sync
= m
.d
.comb
, m
.d
.sync
598 fast_rf
= self
.core
.regs
.rf
['fast']
599 fast_r_dectb
= fast_rf
.r_ports
['issue'] # DEC/TB
600 fast_w_dectb
= fast_rf
.w_ports
['issue'] # DEC/TB
604 # initiates read of current DEC
605 with m
.State("DEC_READ"):
606 comb
+= fast_r_dectb
.addr
.eq(FastRegs
.DEC
)
607 comb
+= fast_r_dectb
.ren
.eq(1)
610 # waits for DEC read to arrive (1 cycle), updates with new value
611 with m
.State("DEC_WRITE"):
613 # TODO: MSR.LPCR 32-bit decrement mode
614 comb
+= new_dec
.eq(fast_r_dectb
.data_o
- 1)
615 comb
+= fast_w_dectb
.addr
.eq(FastRegs
.DEC
)
616 comb
+= fast_w_dectb
.wen
.eq(1)
617 comb
+= fast_w_dectb
.data_i
.eq(new_dec
)
618 sync
+= spr_dec
.eq(new_dec
) # copy into cur_state for decoder
621 # initiates read of current TB
622 with m
.State("TB_READ"):
623 comb
+= fast_r_dectb
.addr
.eq(FastRegs
.TB
)
624 comb
+= fast_r_dectb
.ren
.eq(1)
627 # waits for read TB to arrive, initiates write of current TB
628 with m
.State("TB_WRITE"):
630 comb
+= new_tb
.eq(fast_r_dectb
.data_o
+ 1)
631 comb
+= fast_w_dectb
.addr
.eq(FastRegs
.TB
)
632 comb
+= fast_w_dectb
.wen
.eq(1)
633 comb
+= fast_w_dectb
.data_i
.eq(new_tb
)
639 yield from self
.pc_i
.ports()
642 yield from self
.core
.ports()
643 yield from self
.imem
.ports()
644 yield self
.core_bigendian_i
650 def external_ports(self
):
651 ports
= self
.pc_i
.ports()
652 ports
+= [self
.pc_o
, self
.memerr_o
, self
.core_bigendian_i
, self
.busy_o
,
656 ports
+= list(self
.jtag
.external_ports())
658 # don't add DMI if JTAG is enabled
659 ports
+= list(self
.dbg
.dmi
.ports())
661 ports
+= list(self
.imem
.ibus
.fields
.values())
662 ports
+= list(self
.core
.l0
.cmpi
.lsmem
.lsi
.slavebus
.fields
.values())
665 for sram
in self
.sram4k
:
666 ports
+= list(sram
.bus
.fields
.values())
669 ports
+= list(self
.xics_icp
.bus
.fields
.values())
670 ports
+= list(self
.xics_ics
.bus
.fields
.values())
671 ports
.append(self
.int_level_i
)
674 ports
+= list(self
.simple_gpio
.bus
.fields
.values())
675 ports
.append(self
.gpio_o
)
683 class TestIssuer(Elaboratable
):
684 def __init__(self
, pspec
):
685 self
.ti
= TestIssuerInternal(pspec
)
687 self
.pll
= DummyPLL()
689 # PLL direct clock or not
690 self
.pll_en
= hasattr(pspec
, "use_pll") and pspec
.use_pll
692 self
.pll_18_o
= Signal(reset_less
=True)
694 def elaborate(self
, platform
):
698 # TestIssuer runs at direct clock
699 m
.submodules
.ti
= ti
= self
.ti
700 cd_int
= ClockDomain("coresync")
703 # ClockSelect runs at PLL output internal clock rate
704 m
.submodules
.pll
= pll
= self
.pll
706 # add clock domains from PLL
707 cd_pll
= ClockDomain("pllclk")
710 # PLL clock established. has the side-effect of running clklsel
711 # at the PLL's speed (see DomainRenamer("pllclk") above)
712 pllclk
= ClockSignal("pllclk")
713 comb
+= pllclk
.eq(pll
.clk_pll_o
)
715 # wire up external 24mhz to PLL
716 comb
+= pll
.clk_24_i
.eq(ClockSignal())
718 # output 18 mhz PLL test signal
719 comb
+= self
.pll_18_o
.eq(pll
.pll_18_o
)
721 # now wire up ResetSignals. don't mind them being in this domain
722 pll_rst
= ResetSignal("pllclk")
723 comb
+= pll_rst
.eq(ResetSignal())
725 # internal clock is set to selector clock-out. has the side-effect of
726 # running TestIssuer at this speed (see DomainRenamer("intclk") above)
727 intclk
= ClockSignal("coresync")
729 comb
+= intclk
.eq(pll
.clk_pll_o
)
731 comb
+= intclk
.eq(ClockSignal())
736 return list(self
.ti
.ports()) + list(self
.pll
.ports()) + \
737 [ClockSignal(), ResetSignal()]
739 def external_ports(self
):
740 ports
= self
.ti
.external_ports()
741 ports
.append(ClockSignal())
742 ports
.append(ResetSignal())
744 ports
.append(self
.pll
.clk_sel_i
)
745 ports
.append(self
.pll_18_o
)
746 ports
.append(self
.pll
.pll_lck_o
)
750 if __name__
== '__main__':
751 units
= {'alu': 1, 'cr': 1, 'branch': 1, 'trap': 1, 'logical': 1,
757 pspec
= TestMemPspec(ldst_ifacetype
='bare_wb',
758 imem_ifacetype
='bare_wb',
763 dut
= TestIssuer(pspec
)
764 vl
= main(dut
, ports
=dut
.ports(), name
="test_issuer")
766 if len(sys
.argv
) == 1:
767 vl
= rtlil
.convert(dut
, ports
=dut
.external_ports(), name
="test_issuer")
768 with
open("test_issuer.il", "w") as f
: