+# XXX this needs to move into interface_decl.py
+# and made to use ifaceoutfmtfn and ifaceinfmtfn
+def fmt(ifaces, cells, idx, suffix=None):
+ """ blank entries need to output a 0 to the pin (it could just as
+ well be a 1 but we choose 0). reason: blank entries in
+ the pinmap.txt file indicate that there's nothing to choose
+ from. however the user may still set the muxer to that value,
+ and rather than throw an exception we choose to output... zero.
+
+ NOTE: IMPORTANT. when a function is an output-only there
+ is a special-case assumption that:
+ * (a) GPIO is always the first mux entry
+ * (b) GPIO's outen is also used to set the pad
+ the reason for this is that it is assumed better that
+ multiple pads be switched simutaneously to outputs
+ by setting the GPIO direction rather than having them
+ set arbitrarily by changing the muxer registers.
+ """
+ idx += 1
+ if idx < len(cells):
+ cell = cells[idx]
+ else:
+ cell = ''
+ if not cell:
+ return 'val0'
+ temp = transfn(cell)
+ x = ifaces.getifacetype(temp)
+ if x == 'input':
+ return 'val0' # inputs don't get passed through to the out mux
+ if suffix == '_outen' and x == 'out':
+ return "wr%s%s" % (cells[1], suffix or '') # USE GPIO FOR SELECTION
+ if x == 'out': # sigh hack, should be using interface_decl
+ suffix = ''
+ return "wr%s%s" % (cell, suffix or '')
+
+# XXX this needs to move into interface_decl.py
+
+
+def mkcomment(ifaces, cell, idx, outenmode=False):
+ """ returns a comment string for the cell when muxed
+ """
+ idx += 1
+ if idx >= len(cell):
+ return ' // unused'
+ cname = cell[idx]
+ if not cname:
+ return ' // unused'
+ temp = transfn(cname)
+ x = ifaces.getifacetype(temp)
+ #print (cname, x)
+ if x == 'input':
+ return ' // %s is an input' % cname
+ if outenmode and x == 'inout':
+ return ' // bi-directional'
+ if outenmode and x == 'out':
+ return ' // %s is an output' % cname
+
+ return ""
+
+
+def mkmux(p, ifaces, cell, suffix, outenmode):
+ """ creates a straight many-to-one muxer that accepts
+ multiple inputs and, based on an "address" routes
+ a given indexed input through to the (one) output
+ """
+ cellnum = cell[0]
+ comment = 'outen' if outenmode else 'output'
+ fmtstr = "\t\t\twr%s==%d?%s:%s\n" # mux-selector format
+ ret = ''
+ ret += " // %s muxer for cell idx %s\n" % (comment, cellnum)
+ ret += " %s%s=\n" % (cn(cellnum), suffix)
+ i = 0
+ for i in range(
+ 0, p.get_muxwidth(cellnum) - 1): # full mux range (minus 1)
+ comment = mkcomment(ifaces, cell, i, outenmode)
+ cf = fmt(ifaces, cell, i, suffix)
+ ret += fmtstr % (cn(cell[0]), i, cf, comment)
+ comment = mkcomment(ifaces, cell, i + 1, outenmode)
+ ret += "\t\t\t" + fmt(ifaces, cell, i + 1, suffix) # last line
+ ret += ";%s\n" % comment
+
+ return ret
+
+