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Diffstat (limited to 'manual/PRESENTATION_ExAdv.tex')
| -rw-r--r-- | manual/PRESENTATION_ExAdv.tex | 71 |
1 files changed, 63 insertions, 8 deletions
diff --git a/manual/PRESENTATION_ExAdv.tex b/manual/PRESENTATION_ExAdv.tex index bf9b350f..7aa01424 100644 --- a/manual/PRESENTATION_ExAdv.tex +++ b/manual/PRESENTATION_ExAdv.tex @@ -789,11 +789,11 @@ extract -constports -ignore_parameters \ Unwrap in {\tt test2}: \hfil\begin{tikzpicture} +\node at (0,0) {\includegraphics[width=11cm,trim=1.5cm 1.5cm 1.5cm 1.5cm]{PRESENTATION_ExAdv/macc_xilinx_test2d.pdf}}; +\node at (0,-4) {\includegraphics[width=11cm,trim=1.5cm 1.5cm 1.5cm 1.5cm]{PRESENTATION_ExAdv/macc_xilinx_test2e.pdf}}; \node at (1,-1.7) {\begin{lstlisting}[linewidth=5.5cm, frame=single, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] techmap -map macc_xilinx_unwrap_map.v ;; \end{lstlisting}}; -\node at (0,0) {\includegraphics[width=11cm,trim=1.5cm 1.5cm 1.5cm 1.5cm]{PRESENTATION_ExAdv/macc_xilinx_test2d.pdf}}; -\node at (0,-4) {\includegraphics[width=11cm,trim=1.5cm 1.5cm 1.5cm 1.5cm]{PRESENTATION_ExAdv/macc_xilinx_test2e.pdf}}; \draw[-latex] (4,-0.7) .. controls (5,-1.7) .. (4,-2.7); \end{tikzpicture} \end{frame} @@ -808,10 +808,67 @@ techmap -map macc_xilinx_unwrap_map.v ;; \subsectionpagesuffix \end{frame} -\subsubsection{TBD} +\subsubsection{Changing the design from Yosys} \begin{frame}{\subsubsecname} -TBD +Yosys commands can be used to change the design in memory. Examples of this are: + +\begin{itemize} +\item {\bf Changes in design hierarchy} \\ +Commands such as {\tt flatten} and {\tt submod} can be used to change the design hierarchy, i.e. +flatten the hierarchy or moving parts of a module to a submodule. This has applications in synthesis +scripts as well as in reverse engineering and analysis. + +\item {\bf Behavioral changes} \\ +Commands such as {\tt techmap} can be used to make behavioral changes to the design, for example +changing asynchonous resets to synchronous resets. This has applications in design space exploration +(evaluation of various architectures for one circuit). +\end{itemize} +\end{frame} + +\subsubsection{Example: Async reset to sync reset} + +\begin{frame}[t, fragile]{\subsubsecname} +The following techmap map file replaces all positive-edge async reset flip-flops with +positive-edge sync reset flip-flops. The code is taken from the example Yosys script +for ASIC synthesis of the Amber ARMv2 CPU. + +\begin{columns} +\column[t]{6cm} +\vbox to 0cm{ +\begin{lstlisting}[basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=Verilog] +(* techmap_celltype = "$adff" *) +module adff2dff (CLK, ARST, D, Q); + + parameter WIDTH = 1; + parameter CLK_POLARITY = 1; + parameter ARST_POLARITY = 1; + parameter ARST_VALUE = 0; + + input CLK, ARST; + input [WIDTH-1:0] D; + output reg [WIDTH-1:0] Q; + + wire [1023:0] _TECHMAP_DO_ = "proc"; + + wire _TECHMAP_FAIL_ = !CLK_POLARITY || !ARST_POLARITY; +\end{lstlisting} +\vss} +\column[t]{4cm} +\begin{lstlisting}[basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=Verilog] +// ..continued.. + + + always @(posedge CLK) + if (ARST) + Q <= ARST_VALUE; + else + <= D; + +endmodule +\end{lstlisting} +\end{columns} + \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% @@ -820,10 +877,8 @@ TBD \begin{frame}{\subsecname} \begin{itemize} -\item TBD -\item TBD -\item TBD -\item TBD +\item A lot can be achived in Yosys just with the standard set of commands. +\item The commands {\tt techmap} and {\tt extract} can be used to prototype many complex synthesis tasks. \end{itemize} \bigskip |