from scoreboard.global_pending import GlobalPending
from scoreboard.group_picker import GroupPicker
from scoreboard.issue_unit import IntFPIssueUnit, RegDecode
+from scoreboard.shadow import ShadowMatrix, WaWGrid
from compalu import ComputationUnitNoDelay
self.issue_i = Signal(n_units, reset_less=True)
self.go_rd_i = Signal(n_units, reset_less=True)
self.go_wr_i = Signal(n_units, reset_less=True)
+ self.shadown_i = Signal(n_units, reset_less=True)
+ self.go_die_i = Signal(n_units, reset_less=True)
self.busy_o = Signal(n_units, reset_less=True)
self.rd_rel_o = Signal(n_units, reset_less=True)
self.req_rel_o = Signal(n_units, reset_less=True)
busy_l = []
req_rel_l = []
rd_rel_l = []
+ shadow_l = []
+ godie_l = []
for alu in int_alus:
req_rel_l.append(alu.req_rel_o)
rd_rel_l.append(alu.rd_rel_o)
+ shadow_l.append(alu.shadown_i)
+ godie_l.append(alu.go_die_i)
go_wr_l.append(alu.go_wr_i)
go_rd_l.append(alu.go_rd_i)
issue_l.append(alu.issue_i)
m.d.comb += self.rd_rel_o.eq(Cat(*rd_rel_l))
m.d.comb += self.req_rel_o.eq(Cat(*req_rel_l))
m.d.comb += self.busy_o.eq(Cat(*busy_l))
+ m.d.comb += Cat(*godie_l).eq(self.go_die_i)
+ m.d.comb += Cat(*shadow_l).eq(self.shadown_i)
m.d.comb += Cat(*go_wr_l).eq(self.go_wr_i)
m.d.comb += Cat(*go_rd_l).eq(self.go_rd_i)
m.d.comb += Cat(*issue_l).eq(self.issue_i)
self.req_rel_o = Signal(n_int_alus, reset_less=True)
self.fn_issue_i = Signal(n_int_alus, reset_less=True)
+ # Note: FURegs wr_pend_o is also outputted from here, for use in WaWGrid
+
def elaborate(self, platform):
m = Module()
m.d.comb += intfudeps.rd_pend_i.eq(intregdeps.rd_pend_o)
m.d.comb += intfudeps.wr_pend_i.eq(intregdeps.wr_pend_o)
+ self.wr_pend_o = intregdeps.wr_pend_o # also output for use in WaWGrid
m.d.comb += intfudeps.issue_i.eq(self.fn_issue_i)
m.d.comb += intfudeps.go_rd_i.eq(self.go_rd_i)
# Int ALUs and Comp Units
n_int_alus = 4
m.submodules.cu = cu = CompUnits(self.rwid, n_int_alus)
+ m.d.comb += cu.go_die_i.eq(0)
# Int FUs
m.submodules.intfus = intfus = FunctionUnits(self.n_regs, n_int_alus)
issueunit = IntFPIssueUnit(self.n_regs, n_int_fus, n_fp_fus)
m.submodules.issueunit = issueunit
+ # Shadow Matrix. currently n_int_fus shadows, to be used for
+ # write-after-write hazards
+ m.submodules.shadows = shadows = ShadowMatrix(n_int_fus, n_int_fus)
+ go_rd_rst = Signal(n_int_fus, reset_less=True)
+ go_wr_rst = Signal(n_int_fus, reset_less=True)
+
+ # Write-after-Write grid: selects one shadow to enable, based
+ # on which unit(s) have writes pending and the current instruction
+ # also needing to write
+ m.submodules.wawgrid = wawgrid = WaWGrid(n_int_fus, n_int_fus)
+ busy_prev = Signal(n_int_fus)
+ busy_curr = Signal(n_int_fus)
+ busy_prevbit = Signal(n_int_fus)
+
#---------
# ok start wiring things together...
# "now hear de word of de looord... dem bones dem bones dem dryy bones"
# connect fu-fu matrix
#---------
- # Group Picker... done manually for now. TODO: cat array of pick sigs
+ # Group Picker... done manually for now.
go_rd_o = intpick1.go_rd_o
go_wr_o = intpick1.go_wr_o
go_rd_i = intfus.go_rd_i
go_wr_i = intfus.go_wr_i
- m.d.comb += go_rd_i[0:n_int_fus].eq(go_rd_o[0:n_int_fus]) # rd
- m.d.comb += go_wr_i[0:n_int_fus].eq(go_wr_o[0:n_int_fus]) # wr
+ # NOTE: connect to the shadowed versions so that they can "die" (reset)
+ m.d.comb += go_rd_i[0:n_int_fus].eq(go_rd_rst[0:n_int_fus]) # rd
+ m.d.comb += go_wr_i[0:n_int_fus].eq(go_wr_rst[0:n_int_fus]) # wr
# Connect Picker
#---------
m.d.comb += intpick1.readable_i[0:n_int_fus].eq(int_rd_o[0:n_int_fus])
m.d.comb += intpick1.writable_i[0:n_int_fus].eq(int_wr_o[0:n_int_fus])
+ #---------
+ # Shadow Matrix
+ #---------
+
+ m.d.comb += shadows.issue_i.eq(fn_issue_o)
+ # these are explained in ShadowMatrix docstring, and are to be
+ # connected to the FUReg and FUFU Matrices, to get them to reset
+ # NOTE: do NOT connect these to the Computation Units. The CUs need to
+ # do something slightly different (due to the revolving-door SRLatches)
+ m.d.comb += go_rd_rst.eq(go_rd_o | shadows.go_die_o)
+ m.d.comb += go_wr_rst.eq(go_wr_o | shadows.go_die_o)
+
+ # connect shadows / go_dies to Computation Units
+ m.d.comb += cu.shadown_i[0:n_int_fus].eq(shadows.shadown_o[0:n_int_fus])
+ m.d.comb += cu.go_die_i[0:n_int_fus].eq(shadows.go_die_o[0:n_int_fus])
+
+ # ok connect first n_int_fu shadows to busy lines, to create an
+ # instruction-order linked-list-like arrangement, using a bit-matrix
+ # (instead of e.g. a ring buffer).
+ # XXX TODO
+
+ # when written, the shadow can be cancelled (and was good)
+ m.d.comb += shadows.s_good_i[0:n_int_fus].eq(go_wr_o[0:n_int_fus])
+
+ # work out the current-activated busy unit (by recording the old one)
+ m.d.sync += busy_prev.eq(cu.busy_o)
+ m.d.comb += busy_curr.eq(~busy_prev & cu.busy_o)
+
+ # now the "2D-bit-array-linked-list" can be created, with the
+ # relationships of the previous and current instruction.
+ # *previous* instruction (busy_prev) shadows *current* instruction
+ #m.d.comb += wawgrid.shadow_i.eq(cu.busy_o & ~fn_issue_o)
+ #m.d.comb += wawgrid.fu_i.eq(fn_issue_o)
+
+ # and now we can connect the wawgrid to the shadow matrix. whewww
+ for i in range(n_int_fus):
+ m.d.comb += shadows.shadow_i[i].eq(wawgrid.waw_o[i])
+
#---------
# Connect Register File(s)
#---------
self.regs = [0] * nregs
def op(self, op, src1, src2, dest):
+ maxbits = (1 << self.rwidth) - 1
src1 = self.regs[src1]
src2 = self.regs[src2]
if op == IADD:
- val = (src1 + src2)
+ val = src1 + src2
elif op == ISUB:
- val = (src1 - src2)
+ val = src1 - src2
elif op == IMUL:
- val = (src1 * src2)
+ val = src1 * src2
elif op == ISHF:
- val = (src1 << (src2 & self.rwidth))
- val &= ((1<<(self.rwidth))-1)
+ val = src1 >> (src2 & maxbits)
+ val &= maxbits
self.regs[dest] = val
def setval(self, dest, val):
yield dut.int_store_i.eq(0)
- for i in range(1):
+ for i in range(10):
# set random values in the registers
for i in range(1, dut.n_regs):
- yield dut.intregs.regs[i].reg.eq(31+i*3)
- alusim.setval(i, 31+i*3)
+ val = 31+i*3
+ val = randint(0, (1<<alusim.rwidth)-1)
+ yield dut.intregs.regs[i].reg.eq(val)
+ alusim.setval(i, val)
# create some instructions (some random, some regression tests)
instrs = []
if True:
- for i in range(5):
+ for i in range(10):
src1 = randint(1, dut.n_regs-1)
src2 = randint(1, dut.n_regs-1)
while True:
dest = randint(1, dut.n_regs-1)
+ break
if dest not in [src1, src2]:
break
#src1 = 2
#src2 = 3
#dest = 2
- op = randint(0, 2)
+ op = randint(0, 3)
#op = i % 2
#op = 0
instrs.append( (3, 6, 7, 2) )
instrs.append( (4, 4, 7, 1) )
+ if False:
+ # self-read/write-after-write followed by Read-after-Write
+ instrs.append((1, 1, 1, 1))
+ instrs.append((1, 5, 3, 0))
+
+ if False:
+ # Read-after-Write followed by self-read-after-write
+ instrs.append((5, 6, 1, 2))
+ instrs.append((1, 1, 1, 1))
+
+ if False:
+ # self-read-write sandwich
+ instrs.append((5, 6, 1, 2))
+ instrs.append((1, 1, 1, 1))
+ instrs.append((1, 5, 3, 0))
+
+ if False:
+ # very weird failure
+ instrs.append( (5, 2, 5, 2) )
+ instrs.append( (2, 6, 3, 0) )
+ instrs.append( (4, 2, 2, 1) )
+
# issue instruction(s), wait for issue to be free before proceeding
for i, (src1, src2, dest, op) in enumerate(instrs):
projects / soc.git / blobdiff