.\"   $Id: s2r.1,v 1.2 2002/04/17 14:52:16 franck Exp $
.\" @(#)Labo.l 0.0 90/21/08 UPMC; Author: Fr'ed'eric P'etrot & Franck Wajsburt
.TH S2R 1 "October 1, 1997" "ASIM/LIP6" "ALLIANCE USER COMMANDS"
.SH NAME
.TP
s2r
\- Process mapping from symbolic layout to physical layout
.SH SYNOPSIS
.TP
\fBs2r\fP [\fB-tc1rv\fP] \fIsource\fP [\fIresult\fP]
.so jessie/alliance/alc_origin.1.en.gz
.SH DESCRIPTION
The goal of \fBs2r\fP is to perform the translation from the symbolic layout
to physical layout for the foundry.
\fBs2r\fP uses a technolgy file whose name is defined by the environnement 
variable RDS_TECHNO_NAME.
.br
Some cells, like I/O pads, are specific to a given foundry.
In the symbolic methodology, these cells are phantom cells.
It means that only their abutment box and and connectors are present.
\fBs2r\fP wil substitute physical cells to the symbolic phamtom cells.
Beware, this implies that the manufacturer cells must be modified by hand to
ensure the abutment box is a symbolic grid step multiple, and that the
real connectors are centered on symbolic grid.
.br
In order for the replacement to work well, the physicals cells must have
the abutment box lower left corner at coordinate (0,0)
The name of cells to be replaced are written in the catalog file with the
G attribute, see \fBcatal\fP(5) for details on that file.
See also \fBring\fP(1) for more on pads.
Ouput can be generated in either cif or gds formats, to fit the manufacturer
requirements.
.br
.LP
Mainly two kinds of users are concerned with \fBs2r\fP :
.TP 21
experts
they should be able to parametrize the technology file for a new process
technology file is described in \fBtechno(5)\fP.
.TP
designers
they are not directly concerned with the target process, but need to be able to
compute real capacitances for simulation.
.PP
The \fIsource\fP argument is the name of the symbolic layout file to be
translated.
The optional \fIresult\fP argument indicates the name to be given to the real
layout output.
This name is also the name of the top level model of the layout hierarchy.
If \fIresult\fP name is omitted, then \fIsource\fP name is used.
.PP
Six environment variables must be set for proper usage of \fBs2r\fP,
all of them having default values, thus ensuring the possibility of using it
``as it is''.
.TP 21
MBK_IN_PH
The input format for symbolic layout is given by this environment variable.
The possible values are \fI cp, ap\fP. Default is \fIcp\fP.
See \fBMBK_IN_PH\fP(1) for details.
.TP
MBK_CATA_LIB
Sets the directories that are to be searched thru for reading files. 
The seaching mecanism first look in MBK_WORK_LIB(1) 
MBK_WORK_LIB
defines the path where the generated file is saved.
Make sure the write permissions are set up correctly, otherwise no save
will occur.
.TP
MBK_CATAL_NAME
This indicates the name of the catalog file used for pad substitution.
For the appropriate syntax of this file, see \fBcatal\fP(5). 
.TP
RDS_IN
Defines the format to be used as input for cell substitution.
The available ones are \fIcif\fP and \fIgds\fP (default one).
The cells to be parsed must not containt 45
.ie t \(de
.el degrees
wires. If an unknown layer is encountered, the entire cell will be skipped.
.TP
RDS_OUT
Gives the format of the output file.
This may be either \fIcif\fP or \fIgds\fP (default is \fIgds\fP).
.TP
RDS_TECHNO_NAME
This points to the technology file to be used for symbolic to real translation.
This file is in general shared between all the designers.
it is the full path name to the file location, with the extension.
.SH OPTIONS
Without option, \fBs2r\fP should produce a layout that fits for the foundry.
Nevertheless, its behaviour can be modified when invoked with the
following options:
.TP 21
\-t
Suppress the denotching phase. \fBs2r\fP performs gap filling, denotching
in order to avoid DRC errors. This operation is time consuming.
It is mandatory for the foundry but not really useful for capacitance 
evaluation.
.TP
\-c 
Deletes connectors and node names at all hierarchy level.
Theses objects link the physical view and the logical view of a chip.
If simulation is to be done after physical mapping, connectors must appear,
so that the extractors and simulators can use them.
This must \fInot\fP be used when preparing a final layout for the foundry.
.br
For the factory, the top level connectors are forbidden, since they do not
represent any physical reality.
.TP
\-1
Creates the top level cell with the instances as black boxes.
This may be useful for hierarchical extractors, since the file size may be
greatly reduced.
.TP
\-r
does not replace black boxes.
Cells flagged with the \fBG\fP attribute in the \fBcatal\fP(5) file will not
be replaced by their equivalent layout loaded from disk.
.TP
\-v
verbose mode on.


.SH EXAMPLES
.RS
You should first have a correct execution environment :
.br
It is recommanded to put it in the ``.cshrc'' file if in c shell, as in the
example below.
.RE
.br
.ie t \{\
.ft CR \}
.el \fB
.ta 30n
.nf
       setenv MBK_IN_PH	ap
       setenv MBK_WORK_LIB      ~fred/mbk/layout
       setenv MBK_CATA_LIB      ~franck/s2r:/alliance/cells
       setenv MBK_CATAL_NAME    catalog
       setenv RDS_TECHNO_NAME   /labo/etc/prol15.rds
       setenv RDS_IN            gds
       setenv RDS_OUT           gds
       s2r -c na2_y
.fi
.ft R
.RS
This invocation will produce the cell \fBna2_y\fP from the standard cell
library in real layout, without connectors, scotches if needed, in gds format.
.RE
.SH SEE ALSO
.BR mbk (1),
.BR ring(1),
.BR MBK_IN_PH (1),
.BR MBK_CATA_LIB (1),
.BR MBK_WORK_LIB (1),
.BR MBK_CATAL_NAME (1),
.BR RDS_IN (1),
.BR RDS_OUT (1),
.BR RDS_TECHNO_NAME (1),
.BR techno(5),
.BR catal(5).

.SH DIAGNOSTICS
.br
The actual version of the gds parser and driver doesn't translate neither
connectors, nor node names.
If an extraction on s2r output is needed, cif format will create the
connectors using cif extension \fB4X\fP, and the node names with \fB4N\fP.



.so jessie/alliance/alc_bug_report.1.en.gz