Module Introduction. The module continues with a detailed look at the Green Hills MULTI IDE, and the CodeWarrior IDE.

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1 Module Introduction PURPOSE: This training module describes the MSC8101 hardware and software development environments. Objectives: Identify the features of the MSC8101 ADS. Describe the features and advantages of the SC140 DSP compiler. Describe the development tools provided by Green Hills, including the MULTI IDE. Describe the development tools provided by Freescale, including the CodeWarrior IDE. Contents: 24 pages 6 questions Learning Time: 30 minutes In this training module, we will discuss MSC8101 hardware and software development environments. We will begin by identifying partners in hardware and software development. Then, we will discuss the MSC8101 Application Development System (ADS) and the features of the SC140 architecture that enable you to program in high-level languages efficiently. The module continues with a detailed look at the Green Hills MULTI IDE, and the CodeWarrior IDE.

2 Freescale StarCore Tool Partners SW Dev. Tools RTOS App. SW Simulation Tools Hardware Let s begin with a look at the tool resources for StarCore-based Networking DSPs. To ensure that the development tools used to implement code for StarCore based products provide maximum efficiency, it is essential that tool developers work very closely with core architects and designers throughout the process. For this reason, StarCore created low-level development tools that serve as the baseline for tools developed for the MSC8101. These include Integrated Development Environments from Green Hills, Tasking, and WindRiver. Real-time operating systems are available from Lineo, OSE Systems, and WindRiver. Aisys provides software drivers. In addition, application software for the MSC8101 will be available from Delphi Communications Systems, Hughes Software Systems, Lake Communications, Signals and Software Limited, Surf Communications, and Trinity Convergence. Third-party support for the SC140 DSP core continues to grow as developers benefit from the combined technical support, customer base, and market share of both Freescale and Agere.

3 MSC8101 (ADS) Expansion boards connectors Flash memory SIMM (8 MB to 32 MB) Ethernet (10/100 Mbps) OC-3 (155 Mbps ATM) SDRAM memory (16 MB x 64-bit or 8 MB x 32 bit) on the other side of the board Stereo CODEC connections MSC8101 (in a socket) 2 x RS232 RJ-45 (Quad E1/T1) The MSC8101 Applications Development System, is especially suitable for developing 3G wide-band wireless infrastructure systems, Internet Protocol (IP) telephony systems, Multi-channel modem banks, Multi-channel generic Digital Subscriber Lines (xdsls). The ADS uses a socketed MSC8101. There is an 8 MByte, 80-pin Flash single in-line memory module (SIMM) with support for a 32 MByte SIMM. Also, there is a 16 MByte unbuffered SDRAM on a PowerPC bus soldered directly onto the board. A jumper array controls the data-bus width of 64 or 32 bits. 8 Mbytes of SDRAM memory space supports the narrow data-bus configuration. The board offers a variety of connections and interfaces, including dual RS232 ports, four-channel T1/E1 interface, 155 Mbps Asynchronous Transfer Mode (ATM) user network interface with optical transceiver, Base-T Ethernet port, and a 24-bit Stereo audio Coder/DECoder (CODEC). The ADS has appropriate connectors for the CPM features supported in the 8101 CPM pinout. There are connectors for two expansion boards.

4 The DSP Compiler Challenge Fast Time to Market ASIC Rapid System Verification using C SC140 DSP Compiler RISC DSP application compilation from C has not been viable until now: StarCore SC140 SC140 SC140 Compiler Helps Ease Application Development: Control code density ~80% of typical application code lines ~20% cycle count DSP code performance ~80% of typical application cycle count ~20% code lines) Result: SC140 enables 90% or more of the software code development to be done in C The need for an efficient C compiler is simple; it allows our customers to deliver their products to market faster. This was a critical factor in the design of the SC140. In today's complex system environments, it s common to use a simulation system for rapid system verification in C before determining how to partition the code. The compiler s challenge is to reproduce what is available in C in the native assembly language of the DSP. The SC140 DSP compiler makes this possible. This compiler delivers compact and efficient code, especially control code. In a typical DSP algorithm, the control code is typically 80% of the lines of code, but only 20% of the cycle count. Because of this, the compiler can deliver it with no assembly required. Similarly, the SC140 core can produce very good results on DSP code. However, if you re looking for maximum performance, you can focus on hand optimization for small portions of the code specific to the DSP, which amounts to approximately 20% of the total lines of code. The result is a compiler that enables 90% or more of the code to be developed in C.

5 Programming Flow C Source Files.c,.h C Pre-processor.i Library IR files.lib C Front End (CFE).obj Intermediate Representation (IR) files High Level Optimizations Low Level Optimizations.asm Optimized Assembly Object code Application/ machine config. files Library Object Modules.clb Assembler.cln ccsc100 Shell Linker.cld Executable Program To put the compiler in context, consider this programming flow. The compiler consists of a shell that will run the entire compile process. In this example, the shell is ccsc100. A C pre-processor is included, followed by a C front-end that creates an object file. High-level and low-level optimizations can be used to create an optimized assembly code file. Then, this optimized assembly code is run through the assembler and the linker. You can configure these components to generate object modules or an executable program that can be loaded into the simulator.

6 Intrinsic Functions Enable you to use processor specific features that are not represented in C There are four data types for specific use with intrinsic functions Fractional short Fractional long Extended precision fractional Double extended precision fractional Seven different intrinsic function categories Fractional arithmetic Long fractional arithmetic Double precision arithmetic Extended precision arithmetic SC140 architecture primitives Intrinsic functions enable you to use processor specific features that are not represented in C. These functions include macros and in-line functions that enable fractional and other operations not supported in C. For example, in C, only separate multiply and add instructions are available. By using intrinsic functions, a multiply accumulate (MAC) instruction on the SC140 can be represented. The four data types for specific use with intrinsic functions are shown above: the fractional short, fractional long, extended precision fractional, and double extended precision fractional. There are seven different intrinsic function categories available, including fractional arithmetic, long fractional arithmetic, double precision arithmetic, extended precision arithmetic, and architecture primitives that are unique to the SC140.

7 Question The SC140 architecture enables what percentage of code to be developed in C? Click on your choice. a) 50% b) 70% c) 80% d) 90% Let s review what we have discussed so far with a few questions. Answer: The SC140 compiler allows 90% of the code to be developed in C.

8 Question Why are intrinsic functions important to the compile process? Click on your choice. a) Re-structures the C code for higher level of optimization b) Enables use of processor specific features not represented in C c) Identifies the number of times a code segment will execute for compiler optimization d) All of the above Consider this question about intrinsic functions. Answer: Intrinsic functions are important to the compile process because they enable you to use processor specific features not represented in C.

9 Question In what cases would you potentially want to embed assembly language into a C program? Select all that apply and then click Done. Using legacy code that already exists in assembly language Very critical time requirements that only hand assembly can meet The code contains several fractional operations not supported in C Here s another question for you. Answer: You might want to embed assembly language into a C program when using legacy code that already exists in assembly language, or when your application has very critical time requirements for a piece of code that only hand assembly can meet.

10 Green Hills For StarCore Freescale/Agere chose Green Hills as first 3rd Party for compiler, debugger, and IDE Pre-sales and customer support 25 direct sales offices in U.S. and Europe Distributors in AsiaPac and Australia Optimizing C, C++, EC++ compilers Inline assembly Tracking StarCore ABI C and C++ run-time libraries, including stdio.h VLES packing Let s continue with a look at the tools from Green Hills Software. Green Hills Software (GHS) provides a comprehensive set of development tools. These include include optimizing compilers, MULTI IDE, and kernel awareness integration with ENEA OSE and RTXC real-time operating systems. Green Hills has been profitable in selling and supporting software for over 18 years, with technical offices in the US, Europe, and AsiaPAC. Local offices provide you with resources to support sales and ensure customer satisfaction. The Green Hills Optimizing C and C++ compilers for StarCore use Green Hills' global optimizer with architecturespecific optimizations and generated code. Inline assembly enables the programmer to place assembly code in C/C++ source code. GHS is actively involved with the new StarCore ABI. Their plans to comply with the new StarCore ABI are being finalized. A comprehensive suite of run-time libraries for C and C++ are included. Examples are fileio, which enables standard file I/O calls, such as printf(), to run from the target. Full featured start-up code and libraries include automatic copy of data from ROM to RAM and system call emulation. Source code for the run-time libraries is available, so that users can customize routines according to the specific needs of their applications. The SC140 uses variable length execution sets (VLES), which are VLIW-like groupings of instructions. The StarCore compiler can reorder instructions to maximize VLES packing.

11 Green Hills For StarCore, cont. MULTI IDE Advanced RTOS-aware debugger Multi-core debugger Simsc instruction set simulator Connect to MSC8101ADS board over EOnCE DSP data visualization RTOS Lineo s RTXC Multi-task and kernel awareness debugging MATLAB Graphics Here, we see the features of the MULTI IDE. It contains all of the tools needed to complete a major programming project, including: source level debugger, graphical project builder, text editor, and version control system for code management. Other tools enable you to analyze and optimize code performance. These include a performance profiler that can be run from a simulator or on the board, and features for run-time error checking and code coverage analysis. Simsc is an instruction set simulator that interpretively executes StarCore programs on the host PC or UNIX workstation without the requirement of target hardware. Simsc provides full debug features, host I/O, command window, extended profiling, and hardware break-points. It is shipped with all product packages. MULTI's Data Visualization enables you to select source code variables in the debugger and view their numerical data in a wide range of graphical formats without changing the application code. MULTI s unique kernel and task awareness show the programmer real-time kernel information and a colored debug window for each task.

12 Green Hills Compiler Compiler Optimizations for StarCore Nested hardware loops up to four levels deep ETSI intrinsic functions support Enables fine control over fractional arithmetic. C and C++ run-time libraries provided Versions available to accommodate different processor and memory models (e.g. Endian memory) Start-up code and automatic copy of data from ROM to RAM and system call emulation. Source code to the run-time libraries is available The SC140 architecture has enabled optimizations to the Green Hills compiler. These are shown above. Nested hardware do loops of up to four levels deep can be generated. A large number of ETSI intrinsic functions are supported to allow fine control over fractional arithmetic. Extensive run-time libraries are available to support specific processor features. Additional features are presented on the next page.

13 Green Hills Compiler, cont. Compiler Optimizations for StarCore Constant data section for all string literals, constants, and initialized constant variables VLES packing Reorder instructions to maximize packing Zero data area Data access at arbitrary 32-bit address with single 48- bit instruction. Minimize code size by collecting frequently accessed data into 64K block located in low 16-bits of address space and then accessed with single 32-bit instruction Software pipelining Here, we continue our discussion on the Green Hills optimizing C compiler. All string literals and constants are placed in a distinct section. As noted earlier, StarCore features the variable length execution set, which is covered earlier in this course. The StarCore compiler reorders instructions to maximize the packing and take advantage of this feature. The StarCore compiler can access data stored at an arbitrary 32-bit address with a single 48-bit instruction. However, to minimize code size and to increase the VLES packing opportunities, frequently accessed data can be collected into a 64K block located in the lowest 16-bits of address space. This data can be accessed with a single 32-bit instruction. The StarCore compiler supports software pipelining optimization on loops with both constant and variable bounds. The compiler detects when software pipelining will decrease the cycle count per-iteration, and performs the optimization.

14 Green Hills MULTI Features Feature Optimizing C compiler C++; EC++ Stable/mature Inline assembly Interlaced C/assembly Kernel aware IDE to beat TI Multi-core debug Mature, large sales org Hardware breakpoints GHS Evaluation CD Available To summarize, Green Hills MULTI IDE is a mature and stable development environment. The C Compiler takes advantage of the SC140 s C-friendly architecture, including support for VLES packing. Assembly language may be embedded, and it is RTOS kernel aware. An evaluation CD is available now at the Green Hills site (

15 Question What features are included in Green Hills MULTI IDE? Select all that apply. Code mapping DSP data visualization Instruction set simulator Tcl command-line simulator Multi-task and kernel-aware debugging Consider this question about the Green Hills MULTI IDE. Answer: Correct! The Green Hills MULTI IDE includes DSP data visualization, an instruction set simulator, and multi-task and kernel-aware debugging. Note that CodeWarrior provides code mapping and a Tcl command-line simulator. We will discuss StarCore development tools next.

16 CodeWarrior for StarCore Optimizations for DSP Development Software pipelining Loop optimization Increases level of parallelism Instruction paralleling and scheduling Attempts to execute as many instructions as possible Organizes instructions into execution sets Data and address register allocation Manages processor s registers Minimizes number of memory access Loop invariant code motion Where possible, moves code outside of loop execution CodeWarrior for StarCore DSP Development Tools is a complete IDE, with optimizations and instructions to take advantage of the SC140 architecture. In addition to the target-independent optimizations, which operate on loops, software pipelining provides another level of loop optimization. These optimizations attempt to rearrange the sequence of instructions inside a loop to minimize dependencies between instructions, thereby increasing the level of parallelism. Instruction scheduling optimizations execute as many instructions as possible from the same instruction stream in the same cycle. The amount of dependency between the instructions limits the extent to which this can be achieved. These optimizations organize instructions into execution sets wherever possible, in order to make the best use of the Data Arithmetic Units and Address Generation Units provided by the SC140 architecture. The less often code has to access memory, the faster the code will execute. With register allocation, the compiler manages the processor's register resources so that a minimum number of variables are stored in memory. The compiler tries to keep as many of the program's variables in registers as possible. Loop invariant code motion identifies the activities that don't directly effect the outcome of the loop or its variables and moves them outside of the loop's body. This eliminates the number of the instructions that the loop executes, which results in a tremendous saving in processor cycles. This feature is particularly useful if the loop is called frequently or handles a real-time process.

17 CodeWarrior for StarCore CodeWarrior Features Multi-chip debugging Tcl command-line debugger RTOS kernel aware debugging Profiling Code mapping Here, we see additional features of the CodeWarrior IDE. Note that these are described in detail in the CodeWarrior for StarCore DSP Development Tools Targeting Manual. There is support for multi-chip system development. A multi-processor system is where each processor has some sort of coupling, for example, through a JTAG port. The IDE includes support for Tcl command-line debugging. In addition to using the standard CodeWarrior IDE debugger windows, you can also debug from the command-line using debugging commands specific to the compiler and commands included in the Tcl script language. CodeWarrior for StarCore also supports RTOS kernel aware debugging. This provides access to processes, threads, tasks, queues, semaphores, and mailboxes. The profiler displays information in a graphical format about a specific function and its immediate callers and descendants. There is also code mapping, which is described on the next page.

18 CodeWarrior Code Mapping Clear mapping between original source and generated machine code Requirements: Debugger enabled Symbolics enabled Source file compiled To view code mapping: Click View Code Mapping window Side-by-side code mapping allows you to view the correlation between the C statements and the corresponding assembly code that is generated. You can also trace individual C statements to the assembly code generated, and vice versa. This is a big advantage for designers when optimizing and debugging code. Note that the code mapping features are available even when aggressive optimizations are used in the code.

19 EOnCE Enhanced On Chip Emulation (EOnCE) Module Separate on-chip block that allows non-intrusive interaction with the core Examine contents of registers, memory, and on-chip peripherals in a special debugging environment EOnCE advantages: Reduces system intrusion when debugging Does not require peripherals to be halted during debug mode Includes a rich set of breakpoint features Provides a trace buffer for program flow and data tracing Trace buffer is accessible by the CodeWarrior debugger See SC140 DSP Core Reference Manual for more info Next, let s discuss the Enhanced On-Chip Emulation (EOnCE) module. This module provides debugging features beyond standard debugging. EOnCE enables non-intrusive interaction with the core. You can use it to examine the contents of registers, memory, and on-chip peripherals using a special debugging environment. The CodeWarrior debugger has an EOnCE menu that lets you configure its interface and set trace conditions. With the EOnCE module, you can keep a running trace of tasks and interrupts, and when each occurred. This provides many advantages. System intrusion during debug is reduced, and peripherals do not have to be halted during debug mode It provides rich breakpoint features. One of the main differences between standard software breakpoints and EOnCE breakpoints is that a regular software breakpoint stops program execution immediately before the instruction at which you set the breakpoint. When you set a breakpoint using EOnCE, the program execution is stopped immediately after the instruction. It provides a trace buffer for program flow and data tracing. You can trace up to 2048 bytes of addresses in the buffer. The trace buffer is accessible either by your software or the CodeWarrior debugger. Note that EOnCE is described in detail in Chapter 4 of the SC140 DSP Core Reference Manual (MNSC140CORE/D).

20 StarCore Compilers StarCore compilers Conforms to the ANSI C standard Supports a set of DSP extensions Supports ITU/ETSI primitives for saturating arithmetic Additional intrinsics for non-saturating arithmetic and double-precision arithmetic Allows for standard C constructs representing special addressing modes Command-line versions of compilers Runtime library support Easy integration with assembly language Optimizations Global optimizations Loop optimizations ROM initialization Debugger Interrupt handlers in C Enhanced DWARF-2 debug support Let s discuss the toolset, beginning with the StarCore compiler. A key feature of the Enterprise C Compiler is its ability to generate code that is exceptionally compact; it can approach the code density of the best RISC MPUs, while demonstrating high performance that is comparable to assembly code running on other DSPs. To achieve such high performance, the compiler optimizes code for maximum parallelism in order to take advantage of the SC140 s multiple execution units. In addition, the compiler offers a host of other features that make it ideal for DSP software development, as shown above. This includes conformance with the ANSI C Standard, intrinsic function support, support for runtime libraries and environments, and easy integration with assembly language. Intrinsic function support for ITU/ETSI primitives include saturating, non-saturating, and double-precision arithmetic. The ITU/ETSI primitives provide access to the DSP features. They also allow the compiler to optimize the code around the specific DSP operation being called by the compiler. You can also use inline assembly to access DSP instructions, but this can interfere with the compiler's attempts to optimize to the code, whereas intrinsic functions do not. The optimizer converts preprocessed source files into assembly output code, applying a range of code transformations that can significantly improve the efficiency of the executable program. The goal of the optimizer is to produce output code that is functionally equivalent to the original source code, with improved performance in terms of execution time and/or code size. The toolset can generate code that executes out of ROM. It also manages the data variables that contain initial values. Debugging is made easier by C language interrupt handlers. DWARF enables source-level debugging of embedded programs.

21 StarCore Simulation Complete instruction set simulation of SC140 Core Cycle accurate pipeline modeling Access to registers, memory, and peripherals Enables software development ahead of hardware Ideal for performance benchmarking The last tool we will discuss is the SC140 simulator. This tool enables developers to run and debug software prior to silicon availability. It provides a cycle-accurate pipeline model. Note that the debugger interface is identical for the simulator, ADS, and customer end products. The SC140 simulator is available now and support for peripherals will be available in 2002.

22 Question The CodeWarrior StarCore compilers include which of the following features? Select all that apply and then click Done. VLES packing Zero data area Software pipelining Assembly integration Instruction scheduling Done Let s review what we discussed about CodeWarrior with a couple of questions. Answer: The CodeWarrior StarCore compilers include many features and optimizations. These include software pipelining, assembly integration, and instruction scheduling.

23 Question Which of the following is a feature of the CodeWarrior debugger? Select all that apply and then click Done. C Interrupt handlers EOnCE commands Dwarf-2 debug support Done Consider this question about the CodeWarrior debugger. Answer: The CodeWarrior debugger includes all of these features: C Interrupt handlers, EOnCE commands, and Dwarf-2 debug support.

24 Module Completion MSC8101ADS Programming in C on the SC140 architecture Green Hills development tools Optimizing C, C++, EC++ compilers MULTI IDE development tools Optimized compiler CodeWarrior IDE EOnCE Simulators This concludes our training module on MSC8101 hardware and software development environments. In this module, we identified partners in hardware and software development. We discussed the MSC8101 Application Development System (ADS) and the features of the SC140 architecture that enable you to program in high-level languages efficiently. We also took a detailed look at the development tools for StarCore. This included the Green Hills MULTI IDE, and the CodeWarrior IDE.