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frontend/wishbone: fix wdata.valid being high with old data, use cmd.last=1

This commit is contained in:
Jędrzej Boczar 2020-05-12 13:18:53 +02:00
parent 000a352079
commit 79314f9549
1 changed files with 9 additions and 1 deletions
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10
litedram/frontend/wishbone.py
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@ -28,12 +28,18 @@ class LiteDRAMWishbone2Native(Module):
[("data", port_data_width), ("we", port_data_width//8)], [("data", port_data_width), ("we", port_data_width//8)],
) )
self.submodules += wdata_converter self.submodules += wdata_converter
wdata_lock = Signal()
self.comb += [ self.comb += [
wdata_converter.sink.valid.eq(wishbone.cyc & wishbone.stb & wishbone.we), wdata_converter.sink.valid.eq(wishbone.cyc & wishbone.stb & wishbone.we & ~wdata_lock),
wdata_converter.sink.data.eq(wishbone.dat_w), wdata_converter.sink.data.eq(wishbone.dat_w),
wdata_converter.sink.we.eq(wishbone.sel), wdata_converter.sink.we.eq(wishbone.sel),
wdata_converter.source.connect(port.wdata) wdata_converter.source.connect(port.wdata)
] ]
self.sync += [
If(wdata_converter.sink.valid & wdata_converter.sink.ready,
wdata_lock.eq(1)
)
]
# Read Datapath ---------------------------------------------------------------------------- # Read Datapath ----------------------------------------------------------------------------
rdata_converter = stream.StrideConverter( rdata_converter = stream.StrideConverter(
@ -55,6 +61,7 @@ class LiteDRAMWishbone2Native(Module):
port.cmd.valid.eq(wishbone.cyc & wishbone.stb), port.cmd.valid.eq(wishbone.cyc & wishbone.stb),
port.cmd.we.eq(wishbone.we), port.cmd.we.eq(wishbone.we),
port.cmd.addr.eq(wishbone.adr*ratio + count - adr_offset), port.cmd.addr.eq(wishbone.adr*ratio + count - adr_offset),
port.cmd.last.eq(1),
If(port.cmd.valid & port.cmd.ready, If(port.cmd.valid & port.cmd.ready,
NextValue(count, count + 1), NextValue(count, count + 1),
If(count == (ratio - 1), If(count == (ratio - 1),
@ -69,6 +76,7 @@ class LiteDRAMWishbone2Native(Module):
) )
fsm.act("WAIT-WRITE", fsm.act("WAIT-WRITE",
If(wdata_converter.sink.ready, If(wdata_converter.sink.ready,
NextValue(wdata_lock, 0),
wishbone.ack.eq(1), wishbone.ack.eq(1),
NextState("CMD") NextState("CMD")
) )