SVP64PredMode, SVP64sat, SVP64LDSTmode,
SVP64BCPredMode, SVP64BCVLSETMode,
SVP64BCGate, SVP64BCCTRMode,
+ SVP64width
)
from openpower.consts import EXTRA3, SVP64MODE
from openpower.sv.svp64 import SVP64Rec
https://libre-soc.org/openpower/sv/branches/
LD/ST immed:
-00 0 dz els normal mode (with element-stride)
-00 1 dz rsvd bit-reversed mode
+00 0 zz els normal mode (with element-stride option)
+00 1 zz els Pack/unpack (with element-stride option)
01 inv CR-bit Rc=1: ffirst CR sel
01 inv els RC1 Rc=0: ffirst z/nonz
-10 N dz els sat mode: N=0/1 u/s
+10 N zz els sat mode: N=0/1 u/s
11 inv CR-bit Rc=1: pred-result CR sel
11 inv els RC1 Rc=0: pred-result z/nonz
01 inv dz RC1 Rc=0: ffirst z/nonz
10 N sz dz sat mode: N=0/1 u/s
11 inv CR-bit Rc=1: pred-result CR sel
-11 inv dz RC1 Rc=0: pred-result z/nonz
+11 inv zz RC1 Rc=0: pred-result z/nonz
Arithmetic:
-00 0 sz dz normal mode
-00 1 dz CRM reduce mode (mapreduce), SUBVL=1
-00 1 SVM CRM subvector reduce mode, SUBVL>1
-01 inv CR-bit Rc=1: ffirst CR sel
-01 inv dz RC1 Rc=0: ffirst z/nonz
-10 N sz dz sat mode: N=0/1 u/s
-11 inv CR-bit Rc=1: pred-result CR sel
-11 inv dz RC1 Rc=0: pred-result z/nonz
+| 0-1 | 2 | 3 4 | description |
+| --- | --- |---------|-------------------------- |
+| 00 | 0 | dz sz | simple mode |
+| 00 | 1 | 0 RG | scalar reduce mode (mapreduce), SUBVL=1 |
+| 00 | 1 | SVM 0 | subvector reduce mode, SUBVL>1 |
+| 00 | 1 | SVM 1 | Pack/Unpack mode, SUBVL>1 |
+| 01 | inv | CR-bit | Rc=1: ffirst CR sel |
+| 01 | inv | VLi RC1 | Rc=0: ffirst z/nonz |
+| 10 | N | dz sz | sat mode: N=0/1 u/s, SUBVL=1 |
+| 10 | N | zz 0 | sat mode: N=0/1 u/s, SUBVL>1 |
+| 10 | N | zz 1 | Pack/Unpack sat mode: N=0/1 u/s, SUBVL>1 |
+| 11 | inv | CR-bit | Rc=1: pred-result CR sel |
+| 11 | inv | zz RC1 | Rc=0: pred-result z/nonz |
Branch Conditional:
note that additional BC modes are in *other bits*, specifically
self.pred_sz = Signal(1) # predicate source zeroing
self.pred_dz = Signal(1) # predicate dest zeroing
+ # Modes n stuff
+ self.ew_src = Signal(SVP64width) # source elwidth
+ self.ew_dst = Signal(SVP64width) # dest elwidth
+ self.pack = Signal() # pack mode
+ self.unpack = Signal() # unpack mode
self.saturate = Signal(SVP64sat)
self.RC1 = Signal()
self.cr_sel = Signal(2) # bit of CR to test (index 0-3)
# decode pieces of mode
is_ldst = Signal()
is_bc = Signal()
+ do_pu = Signal() # whether to decode pack/unpack
comb += is_ldst.eq(self.fn_in == Function.LDST)
comb += is_bc.eq(self.fn_in == Function.BRANCH)
mode2 = sel(m, mode, SVP64MODE.MOD2)
with m.Case(0): # needs further decoding (LDST no mapreduce)
with m.If(is_ldst):
comb += self.mode.eq(SVP64RMMode.NORMAL)
+ comb += do_pu.eq(mode[SVP64MODE.LDST_PACK]) # Pack mode
with m.Elif(mode[SVP64MODE.REDUCE]):
comb += self.mode.eq(SVP64RMMode.MAPREDUCE)
+ # Pack only active if SVM=1 & SUBVL>1 & Mode[4]=1
+ with m.If(self.rm_in.subvl != Const(0, 2)): # active
+ comb += do_pu.eq(mode[SVP64MODE.ARITH_PACK])
with m.Else():
comb += self.mode.eq(SVP64RMMode.NORMAL)
with m.Case(1):
with m.If((~is_ldst) & # not for LD/ST
(mode2 == 0) & # first 2 bits == 0
mode[SVP64MODE.REDUCE] & # bit 2 == 1
- (~mode[SVP64MODE.PARALLEL])): # not parallel mapreduce
+ (~mode[SVP64MODE.MOD3])): # bit 3 == 0
comb += self.reverse_gear.eq(mode[SVP64MODE.RG]) # finally whew
# extract zeroing
with m.Default():
comb += self.saturate.eq(SVP64sat.NONE)
+ # extract pack/unpack, actually just ELWIDTH_SRC, so
+ # do elwidth/elwidth_src at same time
+ with m.If(do_pu):
+ comb += self.pack.eq(self.rm_in.ewsrc[0])
+ comb += self.unpack.eq(self.rm_in.ewsrc[1])
+ comb += self.ew_src.eq(self.rm_in.elwidth) # make same as elwid
+ with m.Else():
+ comb += self.ew_src.eq(self.rm_in.ewsrc)
+ comb += self.ew_dst.eq(self.rm_in.elwidth)
+
# extract els (element strided mode bit)
# see https://libre-soc.org/openpower/sv/ldst/
els = Signal()
with m.If(self.rc_in):
comb += els.eq(mode[SVP64MODE.ELS_FFIRST_PRED])
- # Shifted Mode
- with m.If(mode[SVP64MODE.LDST_SHIFT]):
- comb += self.ldstmode.eq(SVP64LDSTmode.SHIFT)
# RA is vectorised
- with m.Elif(self.ldst_ra_vec):
+ with m.If(self.ldst_ra_vec):
comb += self.ldstmode.eq(SVP64LDSTmode.INDEXED)
# not element-strided, therefore unit...
with m.Elif(~els):
projects / openpower-isa.git / blobdiff