\input{configpres}

\section{Xilinx Zynq}

\title{Xilinx Zynq}
\maketitle

\subsection{Zynq FPGA/ARM Design}

\begin{frame}
\frametitle{Zynq FPGA/ARM Design}
\begin{alertblock}{Processing System (PS)}
\begin{itemize}
\item dual-core ARM Cortex-A9 MPCore
\item each core has its own 32KB L1 cache
\item all cores share a single 512KB L2 cache
\item snoop control unit (SCU) to maintain L2 cache coherency between cores
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq FPGA/ARM Design}
\begin{alertblock}{Asymmetric Multi Processing (AMP)}
\begin{itemize}
\item private peripheral interrupts (PPI)
\item separate memory management units (MMU)
\item private timers
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq FPGA/ARM Design}
\begin{alertblock}{Programmable Logic (PL)}
\begin{itemize}
\item PL configured at boot or at a later time
\item supports complete or partial reconfiguration
\item PL configuration data called "bitstream"
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq FPGA/ARM Design}
\begin{alertblock}{Power Domains}
\begin{itemize}
\item PS and PL have separate power domains
\item PS and/or PL can be shutdown if not needed
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{PS Peripherals}

\begin{frame}
\frametitle{PS Peripherals}
\begin{itemize}
\item 2x UART
\item 2x USB (host/gadget/OTG)
\item 2x I2C
\item 2x SPI
\item 2x CAN
\item 2x ethernet
\item Quad-SPI
\item SDIO
\item watchdog
\item static memory controller (SMC) (NAND/SRAM/NOR)
\item GPIO (54 via MIO, 64 inputs (PL->PS) via EMIO, 128 outputs (PS->PL) via EMIO)
\item PCI Express (only on some devices)
\item 256KB on-chip memory (OCM)
\end{itemize}
\end{frame}

\subsection{PS-PL Interfaces}

\begin{frame}
\frametitle{PS-PL Interfaces}
\begin{alertblock}{Accelerator Coherency Port (ACP)}
\begin{itemize}
\item 64-bit interface to allow PL (master) to access OCM or L2
\item low-latency
\item connected directly to SCU, as if it were the CPU
\item cache coherent
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{PS-PL Interfaces}
\begin{alertblock}{High Performance (HP)}
\begin{itemize}
\item 4x master ports for PL
\item for DDR and OCM
\item fifo buffering
\item configurable to maximize performance/throughput
\item must be non-cached or flush/invalidate cache
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{PS-PL Interfaces}
\begin{alertblock}{General Purpose (GP)}
\begin{itemize}
\item 2x master ports
\item 2x slave ports
\item directly mapped
\item low performance
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{Zynq SoC}

\begin{frame}
\frametitle{Zynq SoC}
\begin{figure}[h]
\centering
\includegraphics[width=8.5cm]{images/zynq_soc.png}
\end{figure}
\end{frame}

\subsection{Data Movement Comparison}

\begin{frame}
\frametitle{Data Movement Comparison}
\begin{figure}[h]
\centering
\includegraphics[width=10cm]{images/data_movement_comparison.png}
\end{figure}
\end{frame}

\subsection{Zynq Boot Process}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{Boot Devices}
\begin{itemize}
\item SD
\item NAND
\item QSPI (with optional execute-in-place)
\item NOR (with optional execute-in-place)
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{1. Boot ROM}
\begin{itemize}
\item determine boot source
\item load and execute first stage boot loader (FSBL)
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{2. FSBL}
\begin{itemize}
\item setup pin configuration
\item initialize clocks/RAM
\item optionally perform any security/validation checks
\item optionally program FPGA
\item optionally load data
\item load and execute boot loader
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{3. Bootloader}
\begin{itemize}
\item optionally program FPGA
\item optionally load data
\item load and execute kernel
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{4. Kernel}
\begin{itemize}
\item start up 2nd core
\item setup memory/process management
\item initialize hardware
\item execute userspace environment
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
\begin{alertblock}{5. Userspace}
\begin{itemize}
\item optionally program FPGA
\item optionally trigger more hardware initialization
\item do something useful
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Boot Process}
When should what be loaded?
\begin{alertblock}{Considerations}
\begin{itemize}
\item boot time (delayed initialization)
\item boot device (raw flash management)
\item modularity (updates)
\item flexibility (rescue/maintenance/test systems)
\item complexity (KISS)
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{Zynq Development Tools}

\begin{frame}
\frametitle{Zynq Development Tools/Source}
\begin{alertblock}{Vivado / Vivado HLS / SDK}
\begin{itemize}
\item www.xilinx.com
\item Support - Downloads - Vivado HLx 2016.1
\item All OS Installer Single-File Download (11.16 GB)
\end{itemize}
\end{alertblock}
\begin{alertblock}{Source}
\begin{itemize}
\item git://git.yoctoproject.org/meta-xilinx
\item https://github.com/Xilinx/u-boot-xlnx.git
\item https://github.com/Xilinx/linux-xlnx.git
\item git://github.com/Xilinx/device-tree-xlnx.git
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Development Tools - Vivado}
\begin{alertblock}{Demo}
\begin{itemize}
\item setup zedboard project
\item setup AXI GPIO IP for PL
\item export bitstream
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Zynq Development Tools - SDK}
\begin{alertblock}{Demo}
\begin{itemize}
\item program FPGA via JTAG
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{FPGA Programming}

\begin{frame}
\frametitle{FPGA Programming}
The FPGA can be (re)programmed from nearly all boot stages.
\begin{itemize}
\item FSBL
\item U-Boot
\item Linux Userspace
\end{itemize}
\end{frame}

\subsection{Accessing FPGA from ARM}

\begin{frame}
\frametitle{Accessing FPGA from ARM}
For bare metal applications, Xilinx provides a rich set of API's and examples for many IP blocks.
\begin{alertblock}{Demo}
\begin{itemize}
\item implement bare metal application that uses AXI GPIO IP in PL
\item test the application via JTAG
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}[containsverbatim]
\frametitle{Accessing FPGA from ARM}
Bare metal applications can be loaded and started directly from the FSBL.
\begin{alertblock}{Demo}
\begin{itemize}
\item build FSBL
\item configure FSBL to program the FPGA and run the test application
\end{itemize}
\end{alertblock}
\begin{alertblock}{Boot Image File (BIF)}
\begin{verbatim}
the_ROM_image: {
    [bootloader]fsbl.elf
    design_gpio_wrapper.bit
    bare.elf
}
\end{verbatim}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Accessing FPGA from ARM}
For Linux applications, IP blocks are typically available through the appropriate Linux sub-system API's. (Assuming the IP block driver is implemented as a Linux driver.)
\begin{itemize}
\item PL modules mapped to memory space
\item Linux is not even aware that it is programmable hardware
\end{itemize}
\begin{alertblock}{Demo}
\begin{itemize}
\item configure FSBL to run U-Boot
\item load/run Linux via U-Boot
\item access AXI GPIO IP in PL via sysfs
\item lightshow
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{Asymmetric Multi Processing}

\begin{frame}
\frametitle{Asymmetric Multi Processing}
The FSBL can be configured to load 2 bare metal applications, one on each core.
\begin{alertblock}{Demo}
\begin{itemize}
\item split bare metal test application into 2 applications
\item application 1 on core 1, application 2 on core 2
\item modify application 1 to start application 2
\item configure FSBL to load both applications
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Asymmetric Multi Processing}
The FSBL can be configured to load U-Boot on one core and a bare metal application on the other.
\begin{alertblock}{Demo}
\begin{itemize}
\item modify U-Boot/Linux to restrict memory
\item modify bare metal test application to restrict memory
\item configure FSBL to run U-Boot and load bare metal application
\item activate the bare metal application in U-Boot
\item start the bare metal application from Linux
\end{itemize}
\end{alertblock}
\end{frame}

\begin{frame}
\frametitle{Asymmetric Multi Processing}
Instead of relying on U-Boot to load the kernel, the FSBL can load all components into memory.
\begin{alertblock}{Demo}
\begin{itemize}
\item configure FSBL to load device tree and kernel
\end{itemize}
\end{alertblock}
\end{frame}

\subsection{Bare Metal vs. Process Affinity}

\begin{frame}
\frametitle{Bare Metal vs. Process Affinity}
\begin{alertblock}{bare metal advantages}
\begin{itemize}
\item hardware separation
\item faster startup time
\item less reliance on 3rd party software
\end{itemize}
\end{alertblock}
\begin{alertblock}{Linux application advantages}
\begin{itemize}
\item full operating system features available
\item rich hardware API available
\item simplified development/implementation
\item synchronized shared hardware resources
\end{itemize}
\end{alertblock}
\end{frame}

\input{tailpres}