X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=conferences%2Ffosdem2024%2Ffosdem2024_ddffirst%2Ffosdem2024_ddffirst.tex;h=06301e8998b12505898bd0677ce316c5830e362e;hb=946f05168d76c8040ad982ec649ba8bcd9499c2f;hp=f27646e63f95c4d64b8ec88a5afabca58523a1ee;hpb=eb93d93bb6fa4f31f71816f06473a6589c0bb7c5;p=libreriscv.git

diff --git a/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex b/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
index f27646e63..06301e899 100644
--- a/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
+++ b/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
@@ -84,7 +84,7 @@
    		heat sink normally not required (simplifies overall design)
    		\vspace{3pt}
    \item Fully-integrated peripherals (not Northbridge/Southbridge)\\
-         USB, HDMI, RGB/TTL, SD/MMC, I2C, UART, SPI, GPIO etc. etc. 
+         USB, HDMI, RGB/TTL, SD/MMC, I2C, UART, SPI, GPIO etc. etc.
          \vspace{3pt}
    \item Built-in GPU (shared memory bus, 3rd party licensed) \vspace{3pt}
    \item Built-in VPU (likewise, proprietary)\vspace{3pt}
@@ -183,19 +183,26 @@ for (i = 0; i < VL; i++)
   \begin{itemize}
 	\item 	Positional popcount adds up the totals of each bit set to 1 in each bit-position, of an array of input values.
 	\item   Notoriously difficult to do in SIMD assembler: typically 550 lines
+    \item https://github.com/clausecker/pospop
 
    \end{itemize}
 	
 	\lstinputlisting[language={}]{pospopcount.c}
+
 	
 }
 
 \frame{\frametitle{Pospopcount}
 	
 	\begin{center}
-		\includegraphics[width=0.6\textwidth]{pospopcount.png}
+		\includegraphics[width=0.5\textwidth]{pospopcount.png}
 	\end{center}
-	
+	  \begin{itemize}
+		\item   The challenge is to perform an appropriate transpose of the data (the CPU can only work on registers, horizontally),
+		in blocks that suit the processor and the ISA capacity.
+
+		
+	\end{itemize}
 }
 
 \frame{\frametitle{Pospopcount}
@@ -205,11 +212,10 @@ for (i = 0; i < VL; i++)
 	\end{center}
 
   \begin{itemize}
-  		\item   The challenge is to perform an appropriate transpose of the data,
-  				in blocks that suit the processor and the ISA capacity.
-		\item 	The draft gbbd instruction implemets the transpose, 
-				preparing the data for using the standard popcount instruction.
 
+		\item 	The draft gbbd instruction implements the transpose (shown above),
+				preparing the data to use standard popcount.
+			   (gbbd is based on Power ISA vgbbd, v3.1 p445)
 	
 	\end{itemize}
 	
@@ -259,7 +265,7 @@ for (i = 0; i < VL; i++)
          development costs for customers
    \item It also happens to be fascinating, deeply rewarding technically
          challenging, and funded by NLnet
-         
+
   \end{itemize}
 }
 
@@ -271,7 +277,7 @@ for (i = 0; i < VL; i++)
 		   Questions?\vspace{12pt}
 	}
   \end{center}
-  
+
   \begin{itemize}
 	\item Discussion: http://lists.libre-soc.org
 	\item Freenode IRC \#libre-soc