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from nmigen.build import *
__all__ = ["SPIFlashResources"]
def SPIFlashResources(number, *, cs_n, clk, mosi, miso, wp_n=None, hold_n=None, attrs=None):
resources = []
io_all = []
if attrs is not None:
io_all.append(attrs)
io_all.append(Subsignal("cs_n", Pins(cs_n, dir="o")))
io_all.append(Subsignal("clk", Pins(clk, dir="o")))
io_1x = list(io_all)
io_1x.append(Subsignal("mosi", Pins(mosi, dir="o")))
io_1x.append(Subsignal("miso", Pins(miso, dir="i")))
if wp_n is not None and hold_n is not None:
# Tristate these pins by default, and rely on a pullup on the board or within the flash.
# An alternative would be to define them as outputs with reset value of 1, but that's
# not currently possible in nMigen.
io_1x.append(Subsignal("wp_n", Pins(wp_n, dir="oe")))
io_1x.append(Subsignal("hold_n", Pins(hold_n, dir="oe")))
resources.append(Resource("spiflash", number, *io_1x))
io_2x = list(io_all)
io_2x.append(Subsignal("dq", Pins(" ".join([mosi, miso]), dir="io")))
resources.append(Resource("spiflash2x", number, *io_2x))
if wp_n is not None and hold_n is not None:
io_4x = list(io_all)
io_4x.append(Subsignal("dq", Pins(" ".join([mosi, miso, wp_n, hold_n]), dir="io")))
resources.append(Resource("spiflash4x", number, *io_4x))
return resources
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