#!TCLSH_PATH
#
# Usage:
#	powerbus.tcl <rootname> <leffile> <fillcell>
#
# Take the existing <rootname>.cel file for graywolf input,
# and add fixed-placement fill cells for power bus stripes.
#
#------------------------------------------------------------
# Written by Tim Edwards, July 17, 2016
#------------------------------------------------------------
# LEF dimensions are microns unless otherwise stated.
#------------------------------------------------------------
namespace path {::tcl::mathop ::tcl::mathfunc}

if {$argc != 3} {
   puts stderr "Bad argument list"
   puts stderr "Usage: powerbus.tcl <rootname> <leffile> <fillcell>"
   exit 1
}

set units 100

set cellname [file rootname [lindex $argv 0]]

set celfile ${cellname}.cel
set annofile ${cellname}.acel
set lefname [lindex $argv 1]
set fillcell [lindex $argv 2]

if [catch {open $lefname r} flef] {
   puts stderr "Error: can't open file $lefname for input"
   return
}

if [catch {open $celfile r} fcel] {
   puts stderr "Error: can't open file $celfile for input"
   return
}

if [catch {open $annofile w} fanno] {
   puts stderr "Error: can't open file $annofile for output"
   return
}

#----------------------------------------------------------------
# Read through a LEF file section that we don't care about.
#----------------------------------------------------------------

proc skip_section {leffile sectionname} {
   while {[gets $leffile line] >= 0} {
      if [regexp {[ \t]*END[ \t]+([^ \t]+)[ \t]*$} $line lmatch sectiontest] {
         if {"$sectiontest" != "$sectionname"} {
            puts -nonewline stderr "Unexpected END statement $line "
            puts stderr "while reading section $sectionname"
         }
         break
      }
   }
}

#----------------------------------------------------------------
# Parse the macro contents of the LEF file and retain the information
# about cell size and pin positions.
#----------------------------------------------------------------

proc parse_macro {leffile macroname} {
   global $macroname units

   while {[gets $leffile line] >= 0} {
      if [regexp {[ \t]*SYMMETRY[ \t]+(.+)[ \t]*;} $line lmatch symmetry] {
         set ${macroname}(symmetry) $symmetry
      } elseif [regexp {[ \t]*ORIGIN[ \t]+(.+)[ \t]+(.+)[ \t]*;} $line lmatch x y] {
         set x [expr {int($x * $units + 0.5)}]
         set y [expr {int($y * $units + 0.5)}]
         set ${macroname}(x) $x
         set ${macroname}(y) $y
      } elseif [regexp {[ \t]*SIZE[ \t]+(.+)[ \t]+BY[ \t]+(.+)[ \t]*;} \
                        $line lmatch w h] {
         set w [expr {int($w * $units + 0.5)}]
         set h [expr {int($h * $units + 0.5)}]
         set ${macroname}(w) $w
         set ${macroname}(h) $h

      } elseif [regexp {[ \t]*PIN[ \t]+(.+)[ \t]*$} $line lmatch pinname] {
	 # The fill cell is not expected to have any usable pins
	 skip_section $leffile $pinname
      } elseif [regexp {[ \t]*END[ \t]+([^ \t]+)[ \t]*$} $line lmatch macrotest] {
         if {"$macrotest" == "$macroname"} {
            break
         } else {
            puts stderr "Unexpected END statement $line while reading macro $macroname"
         }
      }
   }
}

#-----------------------------------------------------------------
# Read the lef macro file and get the fill cells and their widths
#-----------------------------------------------------------------

puts stdout "Reading ${fillcell} macros from LEF file."
flush stdout

set fillcells {}

while {[gets $flef line] >= 0} {
   if [regexp {[ \t]*MACRO[ \t]+(.+)[ \t]*$} $line lmatch macroname] {
      # Parse the "macro" statement
      parse_macro $flef $macroname
      if {[regexp "^$fillcell" $macroname] == 1} {
	 # Remember this for later if it's a fill cell
	 lappend fillcells $macroname
      }
   } elseif [regexp {[ \t]*LAYER[ \t]+([^ \t]+)} $line lmatch layername] {
      skip_section $flef $layername
   } elseif [regexp {[ \t]*VIA[ \t]+([^ \t]+)} $line lmatch vianame] {
      skip_section $flef $vianame
   } elseif [regexp {[ \t]*VIARULE[ \t]+([^ \t]+)} $line lmatch viarulename] {
      skip_section $flef $viarulename
   } elseif [regexp {[ \t]*SITE[ \t]+(.+)[ \t]*$} $line lmatch sitename] {
      skip_section $flef $sitename
   } elseif [regexp {[ \t]*UNITS[ \t]*$} $line lmatch] {
      skip_section $flef UNITS
   } elseif [regexp {[ \t]*SPACING[ \t]*$} $line lmatch] {
      skip_section $flef SPACING
   } elseif [regexp {[ \t]*END[ \t]+LIBRARY[ \t]*$} $line lmatch] {
      break
   } elseif [regexp {^[ \t]*#} $line lmatch] {
      # Comment line, ignore.
   } elseif ![regexp {^[ \t]*$} $line lmatch] {
      # Other things we don't care about
      set matches 0
      if [regexp {[ \t]*NAMESCASESENSITIVE} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*VERSION} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*BUSBITCHARS} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*DIVIDERCHAR} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*USEMINSPACING} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*CLEARANCEMEASURE} $line lmatch] {
         incr matches
      } elseif [regexp {[ \t]*MANUFACTURINGGRID} $line lmatch] {
         incr matches
      } else {
         puts stderr "Unexpected input in LEF file:  Only macro defs were expected!"
         puts -nonewline stdout "Line is: $line"
	 flush stdout
      }
   }
}

# If the macro file doesn't define any fill cells, there's not a
# whole lot we can do. . .

if {[llength $fillcells] == 0} {
   puts stdout "No fill cells (${fillname}) found in macro file ${lefname}!"
   exit 1
}

close $flef

# Sort array of fill cells by width

set fillwidths {}
foreach macro $fillcells {
   lappend fillwidths [list $macro [subst \$${macro}(w)]]
}
set fillwidths [lsort -decreasing -index 1 -real $fillwidths]
set fillinfo [lindex $fillwidths 0]
set fillmacro [lindex $fillinfo 0]
set fillvalue [lindex $fillinfo 1]

#------------------------------------------------------------------------
# Determine what width of fill cell and how many are needed to
# accomodate VDD and GND stripes.
# Add these cells as "fixed" types on the right and left sides
# (to-do:  add additional stripes at intervals depending on the
# estimated layout size based on cell height, total cell width, and
# aspect ratio or number of rows)
#------------------------------------------------------------------------

# NOTE:  "500" here is a temporary hack

foreach fillinfo $fillwidths {
   if {[lindex $fillinfo 1] < 500} {break}
   set pwrbusmacro [lindex $fillinfo 0]
   set pwrbuswidth [lindex $fillinfo 1]
}

# Get dimensions of the powerbus fill cell

set right [/ [subst \$${pwrbusmacro}(w)] 2]
set left [- $right [subst \$${pwrbusmacro}(w)]]
set top [/ [subst \$${pwrbusmacro}(h)] 2]
set bottom [- $top [subst \$${pwrbusmacro}(h)]]

# Find the number of rows in the layout;  estimate if aspect ratio
# given.
# NOTE:  "10" here is a temporary hack

set est_numrows 10

#------------------------------------------------------------------------
# Now read the contents of the cel file.  When a cell is found that is
# in the "instlist" list of cells, annotate the next line to increase
# the width by an amount equal to the width of a fill cell.
#
# To do:  Use different fill cell widths according to congestion amount;
# or use multiple fill cells (if different widths are not available).
#------------------------------------------------------------------------

set done_pwrbus 0
while {[gets $fcel line] >= 0} {
   if [regexp {[ \t]*pad[\t]*[0-9]+} $line lmatch] {

      if {$done_pwrbus == 0} {
         puts $fanno ""

         set j 1
         for {set b 1} {$b <= $est_numrows} {incr b} {
            puts $fcel ""
            puts $fcel "cell $i PWRBUS_$j"
            puts $fcel "initially fixed 0 from left of block $b
            puts $fcel "left $left right $right bottom $bottom top $top"
            puts $fcel ""
            incr i
            incr j
         }

         for {set b 1} {$b <= $est_numrows} {incr b} {
            puts $fcel ""
            puts $fcel "cell $i PWRBUS_$j"
            puts $fcel "initially fixed 0 from right of block $b
            puts $fcel "left $left right $right bottom $bottom top $top"
            puts $fcel ""
            incr i
            incr j
         }

         puts $fanno ""
	 set done_pwrbus 1
      }
      puts $fanno $line	  ;# append the pad line and continue

   } else {
      puts $fanno $line	  ;# append the line and continue
   }
}

puts stdout "Done!"