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core/bankmachine: fix auto_precharge (OR on the two buffers for req.lock), don't need to wait for precharge timer to issue auto-precharge

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This commit is contained in:
Florent Kermarrec 2018-08-15 17:03:06 +02:00
parent 2e362ee160
commit bba491396f
1 changed files with 9 additions and 20 deletions
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29
litedram/core/bankmachine.py
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@ -43,27 +43,16 @@ class BankMachine(Module):
# Command buffer
cmd_buffer_layout = [("we", 1), ("adr", len(req.adr))]
if settings.with_auto_precharge:
cmd_buffer_lookahead = stream.SyncFIFO(cmd_buffer_layout, settings.cmd_buffer_depth)
cmd_buffer = stream.Buffer(cmd_buffer_layout) # 1 depth buffer to detect row change
self.submodules += cmd_buffer_lookahead, cmd_buffer
self.comb += [
req.connect(cmd_buffer_lookahead.sink, omit=["wdata_valid", "wdata_ready",
"rdata_valid", "rdata_ready",
"lock"]),
cmd_buffer_lookahead.source.connect(cmd_buffer.sink)
]
else:
cmd_buffer = stream.SyncFIFO(cmd_buffer_layout, settings.cmd_buffer_depth)
self.submodules += cmd_buffer
self.comb += [
req.connect(cmd_buffer.sink, omit=["wdata_valid", "wdata_ready",
"rdata_valid", "rdata_ready",
"lock"])
]
cmd_buffer_lookahead = stream.SyncFIFO(cmd_buffer_layout, settings.cmd_buffer_depth)
cmd_buffer = stream.Buffer(cmd_buffer_layout) # 1 depth buffer to detect row change
self.submodules += cmd_buffer_lookahead, cmd_buffer
self.comb += [
req.connect(cmd_buffer_lookahead.sink, omit=["wdata_valid", "wdata_ready",
"rdata_valid", "rdata_ready",
"lock"]),
cmd_buffer_lookahead.source.connect(cmd_buffer.sink),
cmd_buffer.source.ready.eq(req.wdata_ready | req.rdata_valid),
req.lock.eq(cmd_buffer.source.valid),
req.lock.eq(cmd_buffer_lookahead.source.valid | cmd_buffer.source.valid),
]
slicer = _AddressSlicer(settings.geom.colbits, address_align)
@ -106,7 +95,7 @@ class BankMachine(Module):
self.comb += [
If(cmd_buffer_lookahead.source.valid & cmd_buffer.source.valid,
If(slicer.row(cmd_buffer_lookahead.source.adr) != slicer.row(cmd_buffer.source.adr),
auto_precharge.eq(self.precharge_timer.done & (track_close == 0))
auto_precharge.eq((track_close == 0))
)
)
]