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frotend/avalon: Another simplifiation pass on start condition.

This commit is contained in:
Florent Kermarrec 2023-05-31 10:03:39 +02:00
parent 10837c6a53
commit 9befeb0761
1 changed files with 43 additions and 61 deletions
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104
litedram/frontend/avalon.py
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@ -28,7 +28,7 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
downconvert = ratio > 1 downconvert = ratio > 1
upconvert = ratio < 1 upconvert = ratio < 1
# DownConverter (Optional). # Data-Width Converter (Optional).
if avalon_data_width != port_data_width: if avalon_data_width != port_data_width:
if avalon_data_width > port_data_width: if avalon_data_width > port_data_width:
addr_shift = -log2_int(avalon_data_width//port_data_width) addr_shift = -log2_int(avalon_data_width//port_data_width)
@ -39,23 +39,23 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
address_width = port.address_width + addr_shift, address_width = port.address_width + addr_shift,
data_width = avalon_data_width data_width = avalon_data_width
) )
self.submodules += LiteDRAMNativePortConverter(new_port, port) self.converter = LiteDRAMNativePortConverter(new_port, port)
port = new_port port = new_port
# # # # # #
# Internal Signals. # Internal Signals.
offset = (base_address >> log2_int(port.data_width//8)) burst_count = Signal(9)
burst_start = Signal()
address = Signal(port.address_width)
address_offset = Signal(port.address_width)
byteenable = Signal(avalon_data_width//8)
writedata = Signal(avalon_data_width)
start = Signal()
cmd_ready_seen = Signal()
cmd_ready_count = Signal(9)
burst_count = Signal(9) self.comb += address_offset.eq(base_address >> log2_int(port.data_width//8))
burst_start = Signal()
burst_active = Signal()
address = Signal(port.address_width)
byteenable = Signal(avalon_data_width//8)
writedata = Signal(avalon_data_width)
start = Signal()
cmd_ready_seen = Signal()
cmd_ready_count = Signal(9)
# Layouts. # Layouts.
cmd_layout = [("address", len(address))] cmd_layout = [("address", len(address))]
@ -64,64 +64,46 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
("byteenable", avalon_data_width//8), ("byteenable", avalon_data_width//8),
] ]
self.comb += [
burst_start .eq(avalon.burstcount > 1),
burst_active.eq(burst_count > 0),
]
self.sync += [ self.sync += [
If(start, If(start,
byteenable.eq(avalon.byteenable), byteenable.eq(avalon.byteenable),
writedata.eq(avalon.writedata),
burst_count.eq(avalon.burstcount), burst_count.eq(avalon.burstcount),
address.eq(avalon.address - offset), address.eq(avalon.address - address_offset),
) )
] ]
# FSM. # FSM.
self.submodules.fsm = fsm = FSM(reset_state="START") self.fsm = fsm = FSM(reset_state="START")
fsm.act("START", fsm.act("START",
avalon.waitrequest.eq(1), avalon.waitrequest.eq(1),
If(~burst_start, If(avalon.burstcount <= 1,
port.cmd.addr.eq(avalon.address - offset), port.cmd.addr.eq(avalon.address - address_offset),
port.cmd.we.eq(avalon.write), port.cmd.we.eq(avalon.write),
port.cmd.valid.eq(avalon.read | avalon.write) port.cmd.valid.eq(avalon.read | avalon.write)
), ),
If(avalon.read | avalon.write, If(avalon.read | avalon.write,
If(downconvert, If((avalon.burstcount > 1) | (downconvert == True) | port.cmd.ready,
start.eq(1) start.eq(1),
).Else( If((downconvert == False) & (avalon.burstcount <= 1),
start.eq(burst_start | port.cmd.ready)
)
),
If(start,
If(downconvert,
avalon.waitrequest.eq(1)
).Else(
If(~burst_start,
avalon.waitrequest.eq(0) avalon.waitrequest.eq(0)
) ),
), If(avalon.write,
If(avalon.write, If(avalon.burstcount > 1,
If(burst_start, NextState("BURST_WRITE")
NextState("BURST_WRITE") ).Else(
).Else( port.cmd.last.eq(1),
If(downconvert, NextState("SINGLE_WRITE")
port.wdata.data.eq(avalon.writedata), )
port.wdata.valid.eq(1), ).Elif(avalon.read,
port.wdata.we.eq(avalon.byteenable), If(avalon.burstcount > 1,
), avalon.waitrequest.eq(0),
NextValue(writedata, avalon.writedata), NextValue(cmd_ready_count, avalon.burstcount),
port.cmd.last.eq(1), NextState("BURST_READ")
NextState("SINGLE_WRITE") ).Else(
) port.cmd.last.eq(1),
).Elif(avalon.read, NextState("SINGLE_READ")
If(burst_start, )
avalon.waitrequest.eq(0),
NextValue(cmd_ready_count, avalon.burstcount),
NextState("BURST_READ")
).Else(
port.cmd.last.eq(1),
NextState("SINGLE_READ")
) )
) )
) )
@ -131,7 +113,7 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
avalon.waitrequest.eq(1), avalon.waitrequest.eq(1),
port.rdata.ready.eq(0), port.rdata.ready.eq(0),
If(downconvert, If((downconvert == True),
port.cmd.addr.eq(address), port.cmd.addr.eq(address),
port.cmd.we.eq(1), port.cmd.we.eq(1),
port.cmd.valid.eq(1), port.cmd.valid.eq(1),
@ -150,13 +132,13 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
port.wdata.we.eq(byteenable), port.wdata.we.eq(byteenable),
If(port.wdata.ready, If(port.wdata.ready,
If(downconvert, If((downconvert == True),
avalon.waitrequest.eq(0) avalon.waitrequest.eq(0)
), ),
NextValue(writedata, avalon.writedata), NextValue(writedata, avalon.writedata),
port.flush.eq(1), port.flush.eq(1),
If(downconvert, If((downconvert == True),
NextValue(cmd_ready_seen, 0) NextValue(cmd_ready_seen, 0)
).Else( ).Else(
NextValue(port.cmd.last, 1) NextValue(port.cmd.last, 1)
@ -170,7 +152,7 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
avalon.waitrequest.eq(1), avalon.waitrequest.eq(1),
port.rdata.ready.eq(1), port.rdata.ready.eq(1),
If(downconvert, If((downconvert == True),
port.cmd.addr.eq(address), port.cmd.addr.eq(address),
port.cmd.we.eq(0), port.cmd.we.eq(0),
port.cmd.valid.eq(1), port.cmd.valid.eq(1),
@ -188,7 +170,7 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
avalon.readdata.eq(port.rdata.data), avalon.readdata.eq(port.rdata.data),
avalon.readdatavalid.eq(1), avalon.readdatavalid.eq(1),
If(downconvert, If((downconvert == True),
port.cmd.valid.eq(0), port.cmd.valid.eq(0),
avalon.waitrequest.eq(0), avalon.waitrequest.eq(0),
NextValue(cmd_ready_seen, 0), NextValue(cmd_ready_seen, 0),
@ -211,7 +193,7 @@ class LiteDRAMAvalonMM2Native(LiteXModule):
wdata_fifo.sink.payload.byteenable.eq(avalon.byteenable), wdata_fifo.sink.payload.byteenable.eq(avalon.byteenable),
wdata_fifo.sink.valid.eq(avalon.write & ~avalon.waitrequest), wdata_fifo.sink.valid.eq(avalon.write & ~avalon.waitrequest),
If(avalon.write & burst_active, If(avalon.write & (burst_count > 0),
If(cmd_fifo.sink.ready & cmd_fifo.sink.valid, If(cmd_fifo.sink.ready & cmd_fifo.sink.valid,
NextValue(burst_count, burst_count - 1), NextValue(burst_count, burst_count - 1),
NextValue(address, address + burst_increment) NextValue(address, address + burst_increment)