af28a996fcd7d03d7de0738b452239e5c1f8cf9e
1 """core of the python-based POWER9 simulator
3 this is part of a cycle-accurate POWER9 simulator. its primary purpose is
4 not speed, it is for both learning and educational purposes, as well as
5 a method of verifying the HDL.
8 from functools
import wraps
9 from soc
.decoder
.orderedset
import OrderedSet
10 from soc
.decoder
.selectable_int
import (FieldSelectableInt
, SelectableInt
,
12 from soc
.decoder
.power_enums
import spr_dict
, XER_bits
13 from soc
.decoder
.helpers
import exts
14 from collections
import namedtuple
17 instruction_info
= namedtuple('instruction_info',
18 'func read_regs uninit_regs write_regs ' + \
19 'special_regs op_fields form asmregs')
29 def swap_order(x
, nbytes
):
30 x
= x
.to_bytes(nbytes
, byteorder
='little')
31 x
= int.from_bytes(x
, byteorder
='big', signed
=False)
35 def create_args(reglist
, extra
=None):
47 def __init__(self
, bytes_per_word
=8, initial_mem
=None):
49 self
.bytes_per_word
= bytes_per_word
50 self
.word_log2
= math
.ceil(math
.log2(bytes_per_word
))
51 print ("Sim-Mem", initial_mem
, self
.bytes_per_word
, self
.word_log2
)
54 for addr
, (val
, width
) in initial_mem
.items():
55 #val = swap_order(val, width)
56 self
.st(addr
, val
, width
, swap
=False)
58 def _get_shifter_mask(self
, wid
, remainder
):
59 shifter
= ((self
.bytes_per_word
- wid
) - remainder
) * \
61 # XXX https://bugs.libre-soc.org/show_bug.cgi?id=377
63 shifter
= remainder
* 8
64 mask
= (1 << (wid
* 8)) - 1
65 print ("width,rem,shift,mask", wid
, remainder
, hex(shifter
), hex(mask
))
68 # TODO: Implement ld/st of lesser width
69 def ld(self
, address
, width
=8, swap
=True):
70 print("ld from addr 0x{:x} width {:d}".format(address
, width
))
71 remainder
= address
& (self
.bytes_per_word
- 1)
72 address
= address
>> self
.word_log2
73 assert remainder
& (width
- 1) == 0, "Unaligned access unsupported!"
74 if address
in self
.mem
:
75 val
= self
.mem
[address
]
78 print("mem @ 0x{:x} rem {:d} : 0x{:x}".format(address
, remainder
, val
))
80 if width
!= self
.bytes_per_word
:
81 shifter
, mask
= self
._get
_shifter
_mask
(width
, remainder
)
82 print ("masking", hex(val
), hex(mask
<<shifter
), shifter
)
83 val
= val
& (mask
<< shifter
)
86 val
= swap_order(val
, width
)
87 print("Read 0x{:x} from addr 0x{:x}".format(val
, address
))
90 def st(self
, addr
, v
, width
=8, swap
=True):
92 remainder
= addr
& (self
.bytes_per_word
- 1)
93 addr
= addr
>> self
.word_log2
94 print("Writing 0x{:x} to ST 0x{:x} memaddr 0x{:x}/{:x}".format(v
,
95 staddr
, addr
, remainder
, swap
))
96 assert remainder
& (width
- 1) == 0, "Unaligned access unsupported!"
98 v
= swap_order(v
, width
)
99 if width
!= self
.bytes_per_word
:
104 shifter
, mask
= self
._get
_shifter
_mask
(width
, remainder
)
105 val
&= ~
(mask
<< shifter
)
110 print("mem @ 0x{:x}: 0x{:x}".format(addr
, self
.mem
[addr
]))
112 def __call__(self
, addr
, sz
):
113 val
= self
.ld(addr
.value
, sz
)
114 print ("memread", addr
, sz
, val
)
115 return SelectableInt(val
, sz
*8)
117 def memassign(self
, addr
, sz
, val
):
118 print ("memassign", addr
, sz
, val
)
119 self
.st(addr
.value
, val
.value
, sz
)
123 def __init__(self
, decoder
, regfile
):
127 self
[i
] = SelectableInt(regfile
[i
], 64)
129 def __call__(self
, ridx
):
132 def set_form(self
, form
):
135 def getz(self
, rnum
):
136 #rnum = rnum.value # only SelectableInt allowed
137 print("GPR getzero", rnum
)
139 return SelectableInt(0, 64)
142 def _get_regnum(self
, attr
):
143 getform
= self
.sd
.sigforms
[self
.form
]
144 rnum
= getattr(getform
, attr
)
147 def ___getitem__(self
, attr
):
148 print("GPR getitem", attr
)
149 rnum
= self
._get
_regnum
(attr
)
150 return self
.regfile
[rnum
]
153 for i
in range(0, len(self
), 8):
156 s
.append("%08x" % self
[i
+j
].value
)
158 print("reg", "%2d" % i
, s
)
161 def __init__(self
, pc_init
=0):
162 self
.CIA
= SelectableInt(pc_init
, 64)
163 self
.NIA
= self
.CIA
+ SelectableInt(4, 64)
165 def update(self
, namespace
):
166 self
.CIA
= namespace
['NIA'].narrow(64)
167 self
.NIA
= self
.CIA
+ SelectableInt(4, 64)
168 namespace
['CIA'] = self
.CIA
169 namespace
['NIA'] = self
.NIA
173 def __init__(self
, dec2
, initial_sprs
={}):
176 self
.update(initial_sprs
)
178 def __getitem__(self
, key
):
179 # if key in special_sprs get the special spr, otherwise return key
180 if isinstance(key
, SelectableInt
):
182 key
= special_sprs
.get(key
, key
)
184 return dict.__getitem
__(self
, key
)
187 dict.__setitem
__(self
, key
, SelectableInt(0, info
.length
))
188 return dict.__getitem
__(self
, key
)
190 def __setitem__(self
, key
, value
):
191 if isinstance(key
, SelectableInt
):
193 key
= special_sprs
.get(key
, key
)
194 dict.__setitem
__(self
, key
, value
)
196 def __call__(self
, ridx
):
202 # decoder2 - an instance of power_decoder2
203 # regfile - a list of initial values for the registers
204 def __init__(self
, decoder2
, regfile
, initial_sprs
=None, initial_cr
=0,
205 initial_mem
=None, initial_msr
=0):
206 if initial_sprs
is None:
208 if initial_mem
is None:
210 self
.gpr
= GPR(decoder2
, regfile
)
211 self
.mem
= Mem(bytes_per_word
=8, initial_mem
=initial_mem
)
213 self
.spr
= SPR(decoder2
, initial_sprs
)
214 self
.msr
= SelectableInt(initial_msr
, 64) # underlying reg
216 # FPR (same as GPR except for FP nums)
217 # 4.2.2 p124 FPSCR (definitely "separate" - not in SPR)
218 # note that mffs, mcrfs, mtfsf "manage" this FPSCR
219 # 2.3.1 CR (and sub-fields CR0..CR6 - CR0 SO comes from XER.SO)
220 # note that mfocrf, mfcr, mtcr, mtocrf, mcrxrx "manage" CRs
222 # 2.3.2 LR (actually SPR #8) -- Done
223 # 2.3.3 CTR (actually SPR #9) -- Done
224 # 2.3.4 TAR (actually SPR #815)
225 # 3.2.2 p45 XER (actually SPR #1) -- Done
226 # 3.2.3 p46 p232 VRSAVE (actually SPR #256)
228 # create CR then allow portions of it to be "selectable" (below)
229 self
._cr
= SelectableInt(initial_cr
, 64) # underlying reg
230 self
.cr
= FieldSelectableInt(self
._cr
, list(range(32,64)))
232 # "undefined", just set to variable-bit-width int (use exts "max")
233 self
.undefined
= SelectableInt(0, 256) # TODO, not hard-code 256!
235 self
.namespace
= {'GPR': self
.gpr
,
238 'memassign': self
.memassign
,
243 'undefined': self
.undefined
,
244 'mode_is_64bit': True,
248 # field-selectable versions of Condition Register TODO check bitranges?
251 bits
= tuple(range(i
*4, (i
+1)*4))# errr... maybe?
252 _cr
= FieldSelectableInt(self
.cr
, bits
)
254 self
.namespace
["CR%d" % i
] = _cr
256 self
.decoder
= decoder2
.dec
259 def TRAP(self
, trap_addr
=0x700):
261 # store CIA(+4?) in SRR0, set NIA to 0x700
262 # store MSR in SRR1, set MSR to um errr something, have to check spec
264 def memassign(self
, ea
, sz
, val
):
265 self
.mem
.memassign(ea
, sz
, val
)
267 def prep_namespace(self
, formname
, op_fields
):
268 # TODO: get field names from form in decoder*1* (not decoder2)
269 # decoder2 is hand-created, and decoder1.sigform is auto-generated
271 # then "yield" fields only from op_fields rather than hard-coded
273 fields
= self
.decoder
.sigforms
[formname
]
274 for name
in op_fields
:
276 sig
= getattr(fields
, name
.upper())
278 sig
= getattr(fields
, name
)
280 if name
in ['BF', 'BFA']:
281 self
.namespace
[name
] = val
283 self
.namespace
[name
] = SelectableInt(val
, sig
.width
)
285 self
.namespace
['XER'] = self
.spr
['XER']
286 self
.namespace
['CA'] = self
.spr
['XER'][XER_bits
['CA']].value
287 self
.namespace
['CA32'] = self
.spr
['XER'][XER_bits
['CA32']].value
289 def handle_carry_(self
, inputs
, outputs
, already_done
):
290 inv_a
= yield self
.dec2
.e
.invert_a
292 inputs
[0] = ~inputs
[0]
294 imm_ok
= yield self
.dec2
.e
.imm_data
.ok
296 imm
= yield self
.dec2
.e
.imm_data
.data
297 inputs
.append(SelectableInt(imm
, 64))
298 assert len(outputs
) >= 1
300 gts
= [(x
> output
) for x
in inputs
]
302 cy
= 1 if any(gts
) else 0
303 if not (1 & already_done
):
304 self
.spr
['XER'][XER_bits
['CA']] = cy
306 print ("inputs", inputs
)
308 gts
= [(x
[32:64] > output
[32:64]) == SelectableInt(1, 1)
310 cy32
= 1 if any(gts
) else 0
311 if not (2 & already_done
):
312 self
.spr
['XER'][XER_bits
['CA32']] = cy32
314 def handle_overflow(self
, inputs
, outputs
):
315 inv_a
= yield self
.dec2
.e
.invert_a
317 inputs
[0] = ~inputs
[0]
319 imm_ok
= yield self
.dec2
.e
.imm_data
.ok
321 imm
= yield self
.dec2
.e
.imm_data
.data
322 inputs
.append(SelectableInt(imm
, 64))
323 assert len(outputs
) >= 1
324 print ("handle_overflow", inputs
, outputs
)
329 input_sgn
= [exts(x
.value
, x
.bits
) < 0 for x
in inputs
]
330 output_sgn
= exts(output
.value
, output
.bits
) < 0
331 ov
= 1 if input_sgn
[0] == input_sgn
[1] and \
332 output_sgn
!= input_sgn
[0] else 0
335 input32_sgn
= [exts(x
.value
, 32) < 0 for x
in inputs
]
336 output32_sgn
= exts(output
.value
, 32) < 0
337 ov32
= 1 if input32_sgn
[0] == input32_sgn
[1] and \
338 output32_sgn
!= input32_sgn
[0] else 0
340 self
.spr
['XER'][XER_bits
['OV']] = ov
341 self
.spr
['XER'][XER_bits
['OV32']] = ov32
342 so
= self
.spr
['XER'][XER_bits
['SO']]
344 self
.spr
['XER'][XER_bits
['SO']] = so
348 def handle_comparison(self
, outputs
):
350 out
= exts(out
.value
, out
.bits
)
351 zero
= SelectableInt(out
== 0, 1)
352 positive
= SelectableInt(out
> 0, 1)
353 negative
= SelectableInt(out
< 0, 1)
354 SO
= self
.spr
['XER'][XER_bits
['SO']]
355 cr_field
= selectconcat(negative
, positive
, zero
, SO
)
356 self
.crl
[0].eq(cr_field
)
358 def set_pc(self
, pc_val
):
359 self
.namespace
['NIA'] = SelectableInt(pc_val
, 64)
360 self
.pc
.update(self
.namespace
)
363 def call(self
, name
):
364 # TODO, asmregs is from the spec, e.g. add RT,RA,RB
365 # see http://bugs.libre-riscv.org/show_bug.cgi?id=282
366 info
= self
.instrs
[name
]
367 yield from self
.prep_namespace(info
.form
, info
.op_fields
)
369 # preserve order of register names
370 input_names
= create_args(list(info
.read_regs
) + list(info
.uninit_regs
))
373 # main registers (RT, RA ...)
375 for name
in input_names
:
376 regnum
= yield getattr(self
.decoder
, name
)
378 self
.namespace
[regname
] = regnum
379 print('reading reg %d' % regnum
)
380 inputs
.append(self
.gpr(regnum
))
382 # "special" registers
383 for special
in info
.special_regs
:
384 if special
in special_sprs
:
385 inputs
.append(self
.spr
[special
])
387 inputs
.append(self
.namespace
[special
])
390 results
= info
.func(self
, *inputs
)
393 # detect if CA/CA32 already in outputs (sra*, basically)
396 output_names
= create_args(info
.write_regs
)
397 for name
in output_names
:
403 print ("carry already done?", bin(already_done
))
404 carry_en
= yield self
.dec2
.e
.output_carry
406 yield from self
.handle_carry_(inputs
, results
, already_done
)
407 ov_en
= yield self
.dec2
.e
.oe
.oe
408 ov_ok
= yield self
.dec2
.e
.oe
.ok
410 yield from self
.handle_overflow(inputs
, results
)
411 rc_en
= yield self
.dec2
.e
.rc
.data
413 self
.handle_comparison(results
)
415 # any modified return results?
417 for name
, output
in zip(output_names
, results
):
418 if isinstance(output
, int):
419 output
= SelectableInt(output
, 256)
420 if name
in ['CA', 'CA32']:
422 print ("writing %s to XER" % name
, output
)
423 self
.spr
['XER'][XER_bits
[name
]] = output
.value
425 print ("NOT writing %s to XER" % name
, output
)
426 elif name
in info
.special_regs
:
427 print('writing special %s' % name
, output
, special_sprs
)
428 if name
in special_sprs
:
429 self
.spr
[name
] = output
431 self
.namespace
[name
].eq(output
)
433 regnum
= yield getattr(self
.decoder
, name
)
434 print('writing reg %d %s' % (regnum
, str(output
)))
436 output
= SelectableInt(output
.value
, 64)
437 self
.gpr
[regnum
] = output
439 # update program counter
440 self
.pc
.update(self
.namespace
)
444 """Decorator factory.
446 this decorator will "inject" variables into the function's namespace,
447 from the *dictionary* in self.namespace. it therefore becomes possible
448 to make it look like a whole stack of variables which would otherwise
449 need "self." inserted in front of them (*and* for those variables to be
450 added to the instance) "appear" in the function.
452 "self.namespace['SI']" for example becomes accessible as just "SI" but
453 *only* inside the function, when decorated.
455 def variable_injector(func
):
457 def decorator(*args
, **kwargs
):
459 func_globals
= func
.__globals
__ # Python 2.6+
460 except AttributeError:
461 func_globals
= func
.func_globals
# Earlier versions.
463 context
= args
[0].namespace
# variables to be injected
464 saved_values
= func_globals
.copy() # Shallow copy of dict.
465 func_globals
.update(context
)
466 result
= func(*args
, **kwargs
)
467 args
[0].namespace
= func_globals
468 #exec (func.__code__, func_globals)
471 # func_globals = saved_values # Undo changes.
477 return variable_injector