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lpddr4/test: fixes: use 2tCK write preamble, update read latency

This commit is contained in:
Jędrzej Boczar 2021-03-16 13:31:16 +01:00
parent 5c6796b92a
commit 0ecb1340f5
2 changed files with 31 additions and 16 deletions
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3
litedram/phy/lpddr4/sim.py
View File

@ -530,9 +530,10 @@ class DataSim(Module, AutoCSR):
write = Signal()
read = Signal()
read_skew = 1 # shift the read data as in hardware it will be coming with a delay
self.comb += [
write.eq(cmds_sim.data_en.taps[cwl-1] & cmds_sim.data.source.valid & cmds_sim.data.source.we),
read.eq(cmds_sim.data_en.taps[cl-1] & cmds_sim.data.source.valid & ~cmds_sim.data.source.we),
read.eq(cmds_sim.data_en.taps[cl-1 + read_skew] & cmds_sim.data.source.valid & ~cmds_sim.data.source.we),
cmds_sim.data.source.ready.eq(write | read),
self.dq_wr.masked.eq(write & cmds_sim.data.source.masked),
self.dq_wr.trigger.eq(write),

44
test/test_lpddr4.py
View File

@ -633,8 +633,8 @@ class LPDDR4Tests(unittest.TestCase):
'dq1': (self.CMD_LATENCY+1)*zero + '00000000'+'00000000' + '11111111'+'11111111' + '00000000'+'00000000' + zero,
},
"sys8x_ddr": { # preamble, pattern, preamble
'dqs0': (self.CMD_LATENCY+1)*zero + '01010101'+'01010100' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
'dqs1': (self.CMD_LATENCY+1)*zero + '01010101'+'01010100' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
'dqs0': (self.CMD_LATENCY+1)*zero + '01010101'+'00000101' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
'dqs1': (self.CMD_LATENCY+1)*zero + '01010101'+'00000101' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
}
},
)
@ -671,7 +671,7 @@ class LPDDR4Tests(unittest.TestCase):
def test_lpddr4_dq_in_rddata_valid(self):
# Test that rddata_valid is set with correct delay
read_latency = 8 # settings.read_latency
read_latency = 9 # settings.read_latency
dfi_sequence = [
{0: dict(rddata_en=1)}, # command is issued by MC (appears on next cycle)
*[{p: dict(rddata_valid=0) for p in range(8)} for _ in range(read_latency - 1)], # nothing is sent during write latency
@ -775,7 +775,7 @@ class LPDDR4Tests(unittest.TestCase):
for i in range(16)
},
"sys8x_ddr": {
"dqs0": (self.CMD_LATENCY+1)*zero + '01010101'+'01010100' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
"dqs0": (self.CMD_LATENCY+1)*zero + '01010101'+'00000101' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
},
},
)
@ -787,21 +787,35 @@ class LPDDR4Tests(unittest.TestCase):
read_latency = phy.settings.read_latency
rdphase = phy.settings.rdphase.reset.value
# FIXME: The data will appear 1 cycle before rddata_valid. This is because we have one more cycle
# of read latency that is needed for bitslips to be usable, and here we're not doing read leveling
# so the bitslip is configured incorrectly. If we increased cl by 1 in Simulator and did a single
# bitslip increment before the test, it should work, but this would unnecessarily complicate the test.
dfi_data = {
0: dict(rddata=0x11112222, rddata_valid=1),
1: dict(rddata=0x33334444, rddata_valid=1),
2: dict(rddata=0x55556666, rddata_valid=1),
3: dict(rddata=0x77778888, rddata_valid=1),
4: dict(rddata=0x9999aaaa, rddata_valid=1),
5: dict(rddata=0xbbbbcccc, rddata_valid=1),
6: dict(rddata=0xddddeeee, rddata_valid=1),
7: dict(rddata=0xffff0000, rddata_valid=1),
0: dict(rddata=0x11112222),
1: dict(rddata=0x33334444),
2: dict(rddata=0x55556666),
3: dict(rddata=0x77778888),
4: dict(rddata=0x9999aaaa),
5: dict(rddata=0xbbbbcccc),
6: dict(rddata=0xddddeeee),
7: dict(rddata=0xffff0000),
}
dfi_data_valid = {
0: dict(rddata_valid=1),
1: dict(rddata_valid=1),
2: dict(rddata_valid=1),
3: dict(rddata_valid=1),
4: dict(rddata_valid=1),
5: dict(rddata_valid=1),
6: dict(rddata_valid=1),
7: dict(rddata_valid=1),
}
dfi_sequence = [
{rdphase: dict(cs_n=0, cas_n=0, ras_n=1, we_n=1, rddata_en=1)},
*[{} for _ in range(read_latency - 1)],
*[{} for _ in range(read_latency - 1 - 1)],
dfi_data,
{},
dfi_data_valid,
{},
{},
{},
@ -948,7 +962,7 @@ class LPDDR4Tests(unittest.TestCase):
for i in range(16)
},
"sys8x_ddr": {
"dqs0": init_ddr_latency + '01010101'+'01010100' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
"dqs0": init_ddr_latency + '01010101'+'00000101' + '01010101'+'01010101' + '00010101'+'01010101' + zero,
},
},
)