cores: remove nor_flash_16 (obsolete, most of the boards are now using SPI flash)

diff --git a/litex/soc/cores/nor_flash_16.py b/litex/soc/cores/nor_flash_16.py
deleted file mode 100644 (file)
index 5afad02..0000000
--- a/litex/soc/cores/nor_flash_16.py
+++ /dev/null
@@ -1,107 +0,0 @@
-# This file is Copyright (c) 2013-2015 Sebastien Bourdeauducq <sb@m-labs.hk>
-# License: BSD
-
-from migen import *
-from migen.genlib.fsm import FSM, NextState
-
-from litex.soc.interconnect import wishbone
-
-
-class NorFlash16(Module):
-    def __init__(self, pads, rd_timing, wr_timing):
-        self.bus = wishbone.Interface()
-
-        ###
-
-        data = TSTriple(16)
-        lsb = Signal()
-
-        self.specials += data.get_tristate(pads.d)
-        self.comb += [
-            data.oe.eq(pads.oe_n),
-            pads.ce_n.eq(0)
-        ]
-
-        load_lo = Signal()
-        load_hi = Signal()
-        store = Signal()
-
-        pads.oe_n.reset, pads.we_n.reset = 1, 1
-        self.sync += [
-            pads.oe_n.eq(1),
-            pads.we_n.eq(1),
-
-            # Register data/address to avoid off-chip glitches
-            If(self.bus.cyc & self.bus.stb,
-                pads.adr.eq(Cat(lsb, self.bus.adr)),
-                If(self.bus.we,
-                    # Only 16-bit writes are supported. Assume sel=0011 or 1100.
-                    If(self.bus.sel[0],
-                        data.o.eq(self.bus.dat_w[:16])
-                    ).Else(
-                        data.o.eq(self.bus.dat_w[16:])
-                    )
-                ).Else(
-                    pads.oe_n.eq(0)
-                )
-            ),
-
-            If(load_lo, self.bus.dat_r[:16].eq(data.i)),
-            If(load_hi, self.bus.dat_r[16:].eq(data.i)),
-            If(store, pads.we_n.eq(0))
-        ]
-
-        # Typical timing of the flash chips:
-        #  - 110ns address to output
-        #  - 50ns write pulse width
-        counter = Signal(max=max(rd_timing, wr_timing)+1)
-        counter_en = Signal()
-        counter_wr_mode = Signal()
-        counter_done = Signal()
-        self.comb += counter_done.eq(counter == Mux(counter_wr_mode, wr_timing, rd_timing))
-        self.sync += If(counter_en & ~counter_done,
-                counter.eq(counter + 1)
-            ).Else(
-                counter.eq(0)
-            )
-
-        fsm = FSM()
-        self.submodules += fsm
-
-        fsm.act("IDLE",
-            If(self.bus.cyc & self.bus.stb,
-                If(self.bus.we,
-                    NextState("WR")
-                ).Else(
-                    NextState("RD_HI")
-                )
-            )
-        )
-        fsm.act("RD_HI",
-            lsb.eq(0),
-            counter_en.eq(1),
-            If(counter_done,
-                load_hi.eq(1),
-                NextState("RD_LO")
-            )
-        )
-        fsm.act("RD_LO",
-            lsb.eq(1),
-            counter_en.eq(1),
-            If(counter_done,
-                load_lo.eq(1),
-                NextState("ACK")
-            )
-        )
-        fsm.act("WR",
-            # supported cases: sel=0011 [lsb=1] and sel=1100 [lsb=0]
-            lsb.eq(self.bus.sel[0]),
-            counter_wr_mode.eq(1),
-            counter_en.eq(1),
-            store.eq(1),
-            If(counter_done, NextState("ACK"))
-        )
-        fsm.act("ACK",
-            self.bus.ack.eq(1),
-            NextState("IDLE")
-        )