soc/cores/spi/spi_master: Remove SPISlave.

litex/soc/cores/spi/spi_master.py

@@ -193,94 +193,3 @@ class SPIMaster(Module, AutoCSR):
     def add_clk_divider(self):
         self._clk_divider = CSRStorage(16, description="SPI Clk Divider.", reset=self.clk_divider.reset)
         self.comb += self.clk_divider.eq(self._clk_divider.storage)
-
-# SPI Slave ----------------------------------------------------------------------------------------
-
-class SPISlave(Module):
-    """4-wire SPI Slave
-
-    Provides a simple and minimal hardware SPI Slave with CPOL=0, CPHA=0 and build time configurable
-    data_width.
-    """
-    pads_layout = [("clk", 1), ("cs_n", 1), ("mosi", 1), ("miso", 1)]
-    def __init__(self, pads, data_width):
-        if pads is None:
-            pads = Record(self.pads_layout)
-        if not hasattr(pads, "cs_n"):
-            pads.cs_n = Signal()
-        self.pads       = pads
-        self.data_width = data_width
-
-        self.start    = Signal()            # o, Signal a start of SPI Xfer.
-        self.length   = Signal(8)           # o, Signal the length of the SPI Xfer (in bits).
-        self.done     = Signal()            # o, Signal that SPI Xfer is done/inactive.
-        self.irq      = Signal()            # o, Signal the end of a SPI Xfer.
-        self.mosi     = Signal(data_width)  # i, Data to send on SPI MOSI.
-        self.miso     = Signal(data_width)  # o, Data received on SPI MISO.
-        self.loopback = Signal()            # i, Loopback enable.
-
-        # # #
-
-        clk  = Signal()
-        cs   = Signal()
-        mosi = Signal()
-        miso = Signal()
-
-        # IOs <--> Internal (input resynchronization) ----------------------------------------------
-        self.specials += [
-            MultiReg(pads.clk,    clk),
-            MultiReg(~pads.cs_n,   cs),
-            MultiReg(pads.mosi,  mosi),
-        ]
-        self.comb += pads.miso.eq(miso)
-
-        # Clock detection --------------------------------------------------------------------------
-        clk_d    = Signal()
-        clk_rise = Signal()
-        clk_fall = Signal()
-        self.sync += clk_d.eq(clk)
-        self.comb += clk_rise.eq(clk & ~clk_d)
-        self.comb += clk_fall.eq(~clk & clk_d)
-
-        # Control FSM ------------------------------------------------------------------------------
-        self.submodules.fsm = fsm = FSM(reset_state="IDLE")
-        fsm.act("IDLE",
-            If(cs,
-                self.start.eq(1),
-                NextValue(self.length, 0),
-                NextState("XFER")
-            ).Else(
-                self.done.eq(1)
-            )
-        )
-        fsm.act("XFER",
-            If(~cs,
-                self.irq.eq(1),
-                NextState("IDLE")
-            ),
-            NextValue(self.length, self.length + clk_rise)
-        )
-
-        # Master In Slave Out (MISO) generation (generated on spi_clk falling edge) ----------------
-        miso_data = Signal(data_width)
-        self.sync += [
-            If(self.start,
-                miso_data.eq(self.miso)
-            ).Elif(cs & clk_fall,
-                miso_data.eq(Cat(Signal(), miso_data[:-1]))
-            )
-        ]
-        self.comb += [
-            If(self.loopback,
-                miso.eq(mosi)
-            ).Else(
-                miso.eq(miso_data[-1]),
-            )
-        ]
-
-        # Master Out Slave In (MOSI) capture (captured on spi_clk rising edge) ---------------------
-        self.sync += [
-            If(cs & clk_rise,
-                self.mosi.eq(Cat(mosi, self.mosi[:-1]))
-            )
-        ]