chapter4-embedded software architecturestylee/courses/chapter4... · 2008-03-04 · chapter 4...

Chapter 4Chapter 4Embedded Software ArchitecturesEmbedded Software Architectures

Professor Professor RueiRuei--Xi ChenXi ChenEE--mail: mail: [email protected]@mail.sju.edu.tw

Http://Http://www.csie.sju.edu.twwww.csie.sju.edu.twSJU/CSIESJU/CSIE

P-2/162教育部顧問室PAL聯盟/系統雛型與軟硬體整合設計第四章：嵌入式軟體架構

OutlineOutline4.1 4.1 BootloaderBootloader4.2 Embedded Operating System4.2 Embedded Operating System4.3 Root 4.3 Root FilesystemFilesystem4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system


Software Component Images of Embedded SystemsSoftware Component Images of Embedded SystemsThree Software Component Images

Bootloder imageKernel imageRoot Filesystem image


Root Filesystem

TypicalTypical Embedded SW Image MapsEmbedded SW Image MapsPre-fixed instructions

Can be Fetched from fixed locations during power up.

Ex: Start from 0x00000000Pre-allocated Solid Devices:

FLASHROMOr EEPROM

Typical image map is as shown.

Kernel

Boot ParametersBootloader


4.1 4.1 BootloaderBootloader4.1 4.1 BootloaderBootloader4.2 Embedded Operating System4.2 Embedded Operating System4.3 Root 4.3 Root FilesystemFilesystem4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system


4.1 What is a 4.1 What is a BootloaderBootloader??A special small program

that also called a bootstrap loader.The only job of a boot loader:

To load other software for the operating system to start.


4.1 The Linux 4.1 The Linux BootloaderBootloaderTo initialize platform:

Load the Linux kernelKernel can be downloaded by using tftp/bootp.Kernel is accessed from flash if it resides in Flash.

Run the Linux kernelSetup various initialization parameters:

Command line: root=/dev/nfs ….Platform ID (stored in r1)


4.1 Available 4.1 Available BootloadersBootloaders for ARM Platformsfor ARM PlatformsU-Boot: Universal Bootloader

A firmware for many CPU architectures and boards with full source code under GPL. http://sourceforge.net/projects/u-boot

RedBootA comprehensive debug and bootstrap firmware solution for the development, deployment, and management of embedded devices. http://www.ecoscentric.com/ecos/redboot.shtml

…


4.1 4.1 BootBoot ProcessesProcesses


4.1 Categories of 4.1 Categories of BootloaderBootloader Processing Processing 1. Single-Stage boot loaders2. Multi-Stage boot loaders

Capable of offering good functionality and portabilityOften used


4.1 Coding Style of Multi4.1 Coding Style of Multi--Stage Stage BootloadersBootloadersA Two-Stage Boot Loader is employed.Coding Styles in Stage 1

Mostly coding with assembly languagesFor the efficiency purpose

Coding Styles in Stage 2Coding in C languages

Well readability and portabilityFor ease of complex function realization


4.1 Mission of Two4.1 Mission of Two--stage stage BootloadersBootloadersStage 1：

Hardware Initializing & Load PreparingDuring Power up or System Reset

Assembly languageStage 2：

Load Kernel ImageLaunch Kernel Boot


4.1 Hardware Initialization (Stage 1)4.1 Hardware Initialization (Stage 1)Detect the machine typeInitialization

Mask(阻擋) all Interrupt requestSet Processor’s clock rateMemory & Register InitializationInitialize required peripheralsInitialize the Interrupt controller and Install Interrupt handler.Initialize the indicators (LED etc.)Disable Data and Instruction Cache Memory.


4.1 Load Preparing (Stage 1)4.1 Load Preparing (Stage 1)Prepare RAM space for Stage 2Setup stack

The stack space had better be times of the memory page (4 KB)Set stack pointer: sp = stage2_end - 4

Jump to the Entry-point of Stage 2


Stage1 allocated RAMsapce for Stage 2

ramdisk

Kernel Image

Stage2, 64K(Image of boorloader)

Stage1, 1K(Image of boorloader)

0x0000,0000

0x0000,0400(1KB)

0x0001,0000(64KB)

stage2_end

stage2_startRAM

Flash(Blank)

(Blank)

Stack_Pointer: stage2_end - 4

4.1 Memory Map4.1 Memory Map


4.1 Initialization (Stage 2)4.1 Initialization (Stage 2)Initial

Initialize the Stage 2 required hardwareAt least initialize one serial portInitialize Timers

Examine memory mapAssure the mapping address is accessible

Clear memoryLoader Enabled

Loader: a section code of Boot image


4.1 Load Kernel Images (Stage 2)4.1 Load Kernel Images (Stage 2)Memory allocation

Allocate Kernel image spaceMEM_START + 0x800032k for boot parameters, kernel page table

Allocate Root filesystem spaceMEM_START + 0x00100000

LoadingLoad and extract Kernel image from flash to RAM. Load and extract the root filesystem image from flash to RAM.


4.1 Launch Kernel Boot (Stage 2)4.1 Launch Kernel Boot (Stage 2)Set the starting parameters of kernel.

Tagged list methodsStart kernelInitialize System

By calling kernel functions


4.1 Starting Parameters (Stage 2)4.1 Starting Parameters (Stage 2)Set the starting parameters of kernel

Use the tagged list to pass the starting parameters Starting with ATAG_CORE tagEnding with ATAG_NONE tag

(After version 2.4.x)The starting parameters that need to be set by the Bootloader:

ATAG_COREATAG_MEMATAG_CMDLINE,ATAG_RAMDISKATAG_INITRD


4.1 Start Kernel (Stage 2)4.1 Start Kernel (Stage 2)Jump to MEM_START + 0x8000Setting the CPU registers

R0=0R1=machine type ID

Linux/arch/arm/tools/mach-typesR2=Base address of the starting parameter list in RAMs

CPU modeThe interrupt needs to be inhibited (IRQs and FIQs).It needs to set the CPU as SVC (Switch Virtual Circuit) mode.

Cache and MMU settingDisable MMU

Neglect if the embedded system has no MMU (memory management unit).

Disable data cache


4.1 Initializing System4.1 Initializing SystemCalling kernel functions

Various objects and services functions of kernel:Task objectsTimer servicesMemory management services…

Loading system device driversInitialize hardware devices


4.1 4.1 XSBase255B XSBase255B BootloaderBootloader OperationsOperationsObject

To finish the preparing work properly before the kernel starting.Stage1 :

Devices initialization with the Assembly languageStage2 :

Complex initialization implemented by the C language, but never call any function of glibc.How to jump to the main()?

Directly jump to the entry point of the mainExternal wrappers: write a trampoline program (assembly), and let it be the entry point of the stage 2. Jump to the main from here. The reverse direction is used as it returns.


4.1 4.1 Some SSome Secondecond--Stage Boot LoadersStage Boot LoadersUsed for Stage 2

bootmanGRUBLILOMasterBooterNTLDRXOSLBootXloadlinGujinOSL2000 Boot ManagerBoot CampSyslinuxGAG (Graphical Boot Manager)


4.1 The 4.1 The BootloadersBootloaders SupportSupport


4.1 Sites of the Embedded X86 4.1 Sites of the Embedded X86 BootloadersBootloadersalios

http://www.telos.de/linux/alios/default.htmLinuxBIOS

http://www.acl.lanl.gov/linuxbios/index.htmlNILO(netboot,etherboot)

http://nilo.sourceforge.netTinyBIOS

http://www.pcengines.ch/tinybios.htmROLO

ftp://www/elinos/pub/elinos/rolo


4.1 Other Embedded 4.1 Other Embedded BootloaderBootloader SitesSitesLILO/GRUB

http://lilo.go.dyndns.orghttp://www.gnu.org/software/grub/

Blob :LART projecthttp://www.lart.tudelft.nl/lartwareblob/

U-Boothttp://u-boot.sourceforge.net/http://www.denx.de/re/DPLG.htmlhttp://sourceeforge.net/projects/u-boothttp://armboot.sourceforge.net/

RedBoothttp://www.ecoscentric.com/snapshots/


4.1 The Typical 4.1 The Typical BootloadersBootloadersNTLDR (NT Loader )

For 2000/XP/Server 2003Does not appear in Windows VistaTo load an NT-based OS

LILO (LInux LOader)A generic boot loader for Linux

GRUB (GNU GRUB)A boot loader package from the GNU Project

U-Boot (universal bootloader)PortableEasy to port and debug


4.1 The Typical 4.1 The Typical BootloaderBootloader SupportingSupporting

★★★★RedBoot*

★★★★★★U-Boot*

★Blob

★GRUB

★LILO

★NTLDR

Microblaze(Xilinx)

NIOS(Altera)PPCMIPSARMx86


4.1 NTLDR Boot Process4.1 NTLDR Boot ProcessAccesses the file system on the boot drive (FAT/NTFS)Check if hiberfil.sys exist?

Yes, and its hibernation image is foundLoad its contents into memory and the system resumes where it left off.

OtherwiseReads boot.ini and prompts the user with the boot menu accordingly.

Is a NT-based OS selected?Yes, then NTLDR runs ntdetect.com, which gathers information about the computer's hardware. No, a non NT-based OS is selected, then NTLDR loads the associated file listed in boot.ini and gives it control.

Starts Ntoskrnl.exe, passing to it the information returned by ntdetect.com


4.1 An NTLDR Boot Menu4.1 An NTLDR Boot Menu


4.1 LILO Boot4.1 LILO BootLILO is a versatile boot loader for Linux.

It does not depend on a specific file system.It can boot Linux kernel images from floppy disks and hard disks.It can even boot other operating systems.One of up to sixteen different images can be selected at boot time.Various parameters, such as the root device, can be set independently for each kernel.

LILO can be used as the master boot record.Lately LILO has become a second choice in favor of the GRUBbootloader.


4.1 LILO Boot Features4.1 LILO Boot Features

Linux loaderPlatform

x86Boot device

Floppy,HD,CDROM,CFSupport multi-OS bootingLocation

MBR or 1st sector of Boot partitionConfig file (/etc/lilo.conf)


4.1 The Master Boot Record of LILO4.1 The Master Boot Record of LILOThe first sector of your hard disk

This is where your computer's BIOS will look for instructions onhow to load an operating system.

If you just had Win95 or DOS installedIt would just be an instruction to load that one OS.

LILO gives us the versatility to load more then one OS.


4.1 Standard LILO Display4.1 Standard LILO Display

http://lilo.go.dyndns.org/Website:BSD licenseLicense:BootloaderUse:22.7.3 / August 11, 2006Latest release:

John CoffmanWerner Almesberger

Developer:Original developer:


4.1 Configure LILO4.1 Configure LILOby Manually Editing the lilo.conf File

vi /etc/lilo.confExampleboot=/dev/had1install=/boot/boot.bmap=/boot/mapdefault=linuxtimeout=300image=/boot/vmlinuz-2.4.20label=linux-2.4.20root=/dev/hda1initrd=/boot/initrd.imgother=/dev/hdb1label=WindowsXP


4.1 GNU GRUB 4.1 GNU GRUB GRUB is the reference implementation of the MultibootSpecification.GRUB can be used to:

Select different kernel imagesPass boot-time parameters to such kernels.

the GNU GRUB logo


4.1 GRUB Boot Features4.1 GRUB Boot FeaturesGRand Unified BootloaderPlatform

x86Boot device

Floppy,HD,CDROMSupport multi-OS bootingBoot Location

MBR or 1st sector of Boot partitionConfig file:/boot/grub/menu.lst


4.1 GRUB 4.1 GRUB BBoot Process 1oot Process 1Given the small size of the MBR (master boot record )

MBR: the first 512 bytes of the hard diskStage 1:

Load Stage 2 directlyOr load stage 1.5:

Which located in the first 30 kilobytes of hard disk immediately following the MBR, then Stage 1.5 loads Stage 2.


4.1 GRUB Boot Process 24.1 GRUB Boot Process 2Presents an user interface (UI) to be selected which operating system to boot.

Show graphical menu or a command prompt.For the user to specify the boot parameters

GRUB can also be set to automatically load a particular kernel after a timeout period.

Loads the selected kernel into memory.Passes control on to the kernel

Can pass control of the boot process to another loader using chain loading.


4.1 Configure GRUB4.1 Configure GRUB/boot/grub/memu.lstExampletimeout 10default 0title linuxroot (hd0,0)kernel /vmlinux-2.4.20-8 root=LABEL=/ initrd /initrd-2.4.20-8.imgtitle windows …


4.1 Comparison of GRUB and LILO 4.1 Comparison of GRUB and LILO Different disk partition

GRUB: (hdN,p)LILO: hdaN

ExamplesIDE 1 master drive

LILO :/dev/hda1GRUB:(hd0,0)

IDE 1 slave driveLILO:/dev/hda2GRUB:(hd0,1)

Advantage of GRUBEditable and modifiable boot settingMore flexible


4.1 U4.1 U--BootBootUniversal Boot LoaderOpen source firmware for embedded

PowerPC, ARM, XScale, MIPS, x86, NIOS, MicroBlaze …For Embedded OS

Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS


4.1 U4.1 U--Boot FeaturesBoot FeaturesUniversal Boot LoaderOpen source firmware for embedded Platform:

PowerPC, ARM, XScale, MIPS, x86, Nios, MicroBlaze …For Embedded OS

Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOSReliableConfigurableDevice driverNetworking abilitiesWell documentation


4.1 U4.1 U--Boot SupportBoot SupportNFS/TFTP

KernelRamdisk

Many commandsStore Parameter blocks:

FLASH、NVRAM、EEPROMCRC32 checking

FLASH Kernel, RAMDISKDevice driver:

Serial、SDRAM、FLASH、Ethernet、LCD、NVRAM、EEPROM、keyboard、USB、PCMCIA、PCI、RTC

Post:SDRAM、FLASH size, SDRAM error check, CPU model


4.1 U4.1 U--Boot Directories (1)Boot Directories (1)Board

Board supportSmdk2410/smdk2410.c, config.mk, Makefile, flash.c ,u-boot.lds etc.

Common U-Boot commandsA shell interpreter

hush.c, a prototype Bourne shell grammar parserCpu

Sub-directories including:Serial、networking IC、LCD driverInterrupt initialization

Start.sSetup system stack for jumping to the entry point of C program

Driver For Network Card、CFI Flash、serial and USB…。

Doc U-Boot document

FsU-Boot supported filesystem, such as “jffs2”


4.1 U4.1 U--Boot Directories (2)Boot Directories (2)Examples

For U-Boot executable program examplesHello_world.c, timer.c etc.

IncludeThe “Configs” needed to be modified during porting phase

Lib_xxxXxx: archtecture

NetBootp,nfs,tftp etc.

Post Power on self test

RtcTools


4.1 U4.1 U--Boot Porting ReferencesBoot Porting ReferencesSource codehttp://sourceforge.net/projects/U-BootDULG（The DENX U-Boot and Linux Guide）http://www.denx.de/twiki/bin/view/DULG/ManualU-Boot mail listshttp://lists.sourceforge.net/lists/listinfo/u-boot-usershttp://sourceforge.net/mailarchive/forum.php?forum_id=12898


4.1 Porting/Customizing u4.1 Porting/Customizing u--bootbootFiles familiarization

Architecture (core) specific filesCPU specific filesBoard specific filesCommon to all platforms

General ModificationsBoard specific Source files & MakefilesConfiguration files

Build, Install & Deploy


4.1 U4.1 U--Boot Boot ProcessBoot Boot ProcessInvoke U-BootStarts running from ROMRelocates itself to RAMInitial setup and environment checksLocate the kernel and decompress itCheck CRC of kernelTransfer control to kernel imageKernel boots


4.1 U4.1 U--Boot booting (1)Boot booting (1)Preliminary setup

CPUMemory

Relocate self to RAMInitialize ARM boot

FlashEnvironmentIP & MAC address


4.1 U4.1 U--Boot booting (2)Boot booting (2)Initialize ARM boot (continued)

DevicesConsoleInterruptsEthernet

Boot kernelRead image headerDecompress imageTransfer control to kernel


4.1 U4.1 U--Boot SecurityBoot SecurityOnly knows CRCBasically a sophisticated checksumCRC good for finding random errors in a transmissionLittle protection against malicious attacks


4.1 U4.1 U--Boot Command CategoriesBoot Command CategoriesInformation commandsMemory commandsFlash memory commandsExecution commandsDownloadEnvironment variablesSpecialMiscellaneous


4.1 Some U4.1 Some U--Boot CommandsBoot CommandsHelp:

Print online helpFlinfo:

Print FLASH memory information

Protect:Enable or disable FLASH write

Protection

Erase:Erase FLASH memory

Loadb:Loadb binary file over serial line (kermit mode)

Md:Memory display

Cp:Memory copy

Command usage:Help + commands


4.1 U4.1 U--BootCommandBootCommand Lists (1)Lists (1)

print FLASH memory informationflinfoerase FLASH memoryeraseecho args to consoleechochecksum calculationcrc32memory copycpmemory comparecmpboot default, i.e., run 'bootcmd'bootdboot image via network using BootP/TFTP protocolbootpboot application image from memorybootmprint Board Info structurebdinfoprint or set address offsetbaserun script from memoryautoscrFunctionCommand



memory write (fill)mwsimple RAM testmtestmemory modify (auto-incrementing)mmmemory displaymdinfinite loop on address rangeloopload S-Record file over serial lineloadsload binary file over serial line (ymodem-g mode)loadgload binary file over serial line (ymodem-c mode)loadcload binary file over serial line (kermit mode)loadbprint header information for application imageiminfoprint online helphelpstart application at address 'addr'goFunctionCommand



alias for 'help'?print monitor versionversion

boot image via network using TFTP protocol and envvariables ipaddr and serverip

tftpbootdelay execution for some timesleepset environment variablessetenvsave environment variables to persistent storagesaveenvrun commands in an environment variablerunperform RESET of the CPUresetboot image via network using RARP/TFTP protocolrarpbootenable or disable FLASH write protectionprotectprint environment variablesprintenvmemory modify (constant address)nmFunctionCommand


4.1 Examples of U4.1 Examples of U--BOOT Command UsageBOOT Command Usagehelp USBsetenv serverip xxx.xxx.xxx.xxxsetenv ipaddr yyy.yyy.yyy.yyysetenv bootcmd ‘tftp 33000000 uImage_2410; go 33000000tftp: tftp 33000000 uImage_2410go 32000000bootm 33000000mw 33000000 ff 10000nfs 33000000 xxx.xxx.xxx.xxx:aa.txt


4.1 Operation Modes of Boot Loaders4.1 Operation Modes of Boot Loaders1. Boot loading Mode

Autonomous ModeLoading during power on

2. Downloading Mode


4.1 The Downloading mode4.1 The Downloading modeAn alternative of the Boot loading modeThe bootloader often use the following protocols are to connect the Target and Host:

UART Protocol Usually as xmodem, ymodem, zmodemThe speed is limited

TFTP Protocol (network transferring)The Host needs to provide TFTP service

Downloading documents from the HostSuch as the image


4.2 Embedded Operating System4.2 Embedded Operating System4.1 4.1 BootloaderBootloader4.2 Embedded Operating System4.2 Embedded Operating System4.3 Root 4.3 Root FilesystemFilesystem4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system


4.2 Architecture of Embedded Systems4.2 Architecture of Embedded Systems


4.2 4.2 Typical Embedded OTypical Embedded Operating Systemsperating SystemsWindows CE /Mobile WindowsPalm OSEPOCuC/OS-IISymbian OSRTOS:

VxWorks, pSOS…Linux:

uClinux, Montavista Linux, ARM-Linux…


4.2 WinCE Architectures4.2 WinCE Architectures


4.2 Advantages of WinCE4.2 Advantages of WinCEBenefits

Built-in NAND Flash bootloader, SD HostVarious embedded IPDesign time reduction with a supporting reference board & RTOSVarious design applications

Key ApplicationsWireless PDASmartphoneGame machinesPoint-of-Sale terminalsPortable media players


4.2 Memory Map of WinCE4.2 Memory Map of WinCE

64MB physical address and 4GB virtual addressCPU

– MIPS和SHXThe mapping of physical

address is made by CPU– x86和ARM

All physical addresses are mapped to the virtual addresses above 0x80000000Above 0x80000000 is used by kernelBelow 0x80000000 is used by applications


4.2 Memory Allocations4.2 Memory Allocations0x0000 0000~0x41FF FFFF

Used by all applications33 slots, every one is 32MB

Slot0（Slot 0）used by the current ProcessSlot1 is used by XIP DLL（in .NET)Other slot is for Processes，each process use a slotMaximum 32 Processes simultaneously

0x4200 0000~0x7FFF FFFFCommon area of all the applicationsFor creating the stacks, the image documents, and the patch of large space

0xC000 0000~0xC1FF FFFFSystem reserved

0xC200 0000~0xC3FF FFFFUsed by the kernel program nk.exe

0xE000 0000~0xFFFF FFFFVirtual space used by the kernel for configuring a larger virtual space


4.2 Linux Kernel4.2 Linux Kernel

From http://www.xml.com/ldd/chapter/book/bookindexpdf.html (GPL)


4.2 Linux and GNU Roadmap4.2 Linux and GNU Roadmap


4.2 Open Source Model4.2 Open Source Model


4.2 4.2 Open Source Embedded LinuxOpen Source Embedded LinuxEmbedded Debian Project

Convert Debian to an embedded OSETLinux

For PC104 SBC’suCLinux

For microprocessors that don’t have MMuLinux (muLinux)

Distro fits on a single floppy


4.2 4.2 Commercial Embedded Linux (1)Commercial Embedded Linux (1)AMIRIX Embedded Linux

Derived from DebianCoollogic Coollinux

Combines Linux and Java for Internet appsCoventive Xlinux

Kernel can be as small as 143KBEsfia RedBlue Linux

400K, designed for wireless appsKYZO Pizza Box Linux

SAMBA based file, print, CD serverLineo Embedix

Supports real time and high availability appsLynuxWorks BlueCat

General purpose embedded solutionMontaVista Linux

General purpose embedded solution


4.2 4.2 Commercial Embedded Linux (2)Commercial Embedded Linux (2)Neoware NeoLinux

Red Hat derived for information appliancesPalmPalm Tynux

Internet appliuance and multimediaRed Hat Embedded Linux

general purpose embedded solutionRedSonic Red-Ice Linux

runs from DiskonChip or CompactFlashRidgeRun DSP Linux

for multimedia, wireless, RT on DSPTimeSys Linux GPL

low latency enhanced kernelTuxia TASTE

distro targets Internet appliancesVital Systems vLinux

for ARM based embedded apps


4.2 Kernel Space4.2 Kernel SpaceKernel structure

Data structure of ProcessProcess ID, Priority, Status, Registers used, Interrupt, Global variables

Process ManagementUser’s service routines in a forever loop

Time ManagementRequired time delay for interrupt

Inter-process Communication & SynchronizationSemaphores, message boxes, message queues

Memory ManagementMechanism of memory allocation and release


4.2 Kernel Architecture of RTOS4.2 Kernel Architecture of RTOSKernel Primitive

Issue system calls for InterruptsInterfacing the processes to the system

Interrupt Service Routine (ISR)Software interrupt & hardware interrupt

Process SchedulerA dispatcher

First-come-first-serviced Scheduling (FCFS)Priority Scheduling (PS)

PreemptiveNon-preemptive


4.2 Basic Kernel Program4.2 Basic Kernel ProgramSynchronization

Semaphores: Accessed by Pend() and Post()Buffer management

Request() and Release()Data transfer

Send() and Receive()Interrupt Management

EnableINT() and DisableINT()Process Management

Process Control Block (PCB)Process state: running, waiting, readyContext switch


4.2 4.2 uCLinuxuCLinux StructureStructure


4.2 Building Linux Kernels4.2 Building Linux KernelsDownload reference kernel

http://www.kernel.orgDownload and apply associated ARM patch

http://www.arm.linux.org.uk/developer/This is applied on unpacked base kernelAdd additional patches as appropriate

Configure the kernel (make xconfig)Choose architecture, development platform, devices and functionality needed

Build the kernelEnsure the right link is set in main Makefile to point at the cross compiler location


4.2 Running Linux kernels4.2 Running Linux kernelsBuilt image is in arch/arm/boot directoryLoading and running the image on the target:

Use BootLoaderEither via network (tftp/bootp) or from flash

Use DebuggerLoad image as raw binary:

(@0x8000 for uncompressed Image)Set platform ID in r1 and initialise r0, r2Disable semi-hosting and vector catchSet pc=0x8000 and run the kernel


4.2 4.2 Building XSBase255B Linux kernelBuilding XSBase255B Linux kernelSetup KernelDirectories and filesSetup Makefile and config.inAdd applications to Kernel


4.2 Kernel Directory Structure4.2 Kernel Directory Structure


4.2 4.2 Description of Kernel Description of Kernel DirectoriesDirectories/usr/src/linux

Kernel directory for target system Sub directories of linux

archkernel programs of all related architecture (arm etc.)

includeHeader files (Our header files is put in asm-arm directory)

initKernel initialized programThe starting point to study kernel functions

mmMemory management related functions

kernelSystem functions of Kernel

driversDevice drivers

libLibraries

How to show kernel versions?Command: uname –r


4.2 Kernel Configuration 4.2 Kernel Configuration Three part of files required1. Makefile2. Config.in3. Configuration tools(圖形介面, 用戶配置…)


4.2 4.2 MakefileMakefile and and config.inconfig.inMakefile

Makefile will recursively enter every sub directory of kernel, and use their Makefile.Include arch/$(ARCH)/Makefile

The assignment of CPU architecturesConfig.in

The script file for system configuration Add the manual item to the Linux configurationMakefile use the arch/arm/config.in (scripts/Configure) to do the configuration.A .config file created after configuration


4.2 Steps of Kernel Configuration4.2 Steps of Kernel Configurationmake configmake oldconfigmake menuconfig

EX: shell>make ARCH=ARM CROSS_COMPILE=arm-linuxmenuconfig

make xconfigX windows menu


4.2 Make 4.2 Make menuconfigmenuconfig環境設置


4.2 System Type4.2 System TypeSelect PXA25x-based CPU


4.2 PCMCIA/4.2 PCMCIA/CardBusCardBus SupportSupport


4.2 Flash Chip Interfaces4.2 Flash Chip InterfacesFor RAM/ROM interface drivers


4.2 Mapping Drivers for CF Card Access4.2 Mapping Drivers for CF Card Access


4.2 Ethernet Options (10 or 1004.2 Ethernet Options (10 or 100--Mbps)Mbps)CS8900 chip support

Support XSCALE PXA255 Ethernet


4.2 Console Drivers4.2 Console DriversSupport for frame buffer devicesPXA LCD support


4.2 4.2 Add Other DriversAdd Other DriversDevice drivers are typically distributed in one of three forms:

A PATCH AGAINST A SPECIFIC KERNEL VERSIONThe most common of all

#cd /usr/src/linux ; patch -p1 < patch_fileA LOADABLE MODULEAN INSTALLATION SCRIPT THAT APPLIES APPROPRIATE PATCHES

Add new functions to KernelThree steps to complete

Put new program into the kernel folderAdd the select item for the configurationCreate Makefile of Sub-directory


4.2 4.2 Step1Step1Add a new folder with the Makefile and config.in to the drivers directory.Modify the config.in of the up layerModify the Makefile of the up layerAssure the initialization function is called

Direct build-in in the kernel folderUse the upload/download mode


4.2 4.2 Step2Step2Drivers/test/Config.in

Arch/arm/config.inAdd the following to the last line

source drivers/test/Config.in


4.2 4.2 Step3Step3Editing the makefile (drivers/test/Makefile)


4.2 Modify the 4.2 Modify the MakefilesMakefilesDrivers/Makefile

Makefile


4.2 4.2 Make KernelMake Kernel$make menuconfig$make dep$make zImage


4.2 Burning the 4.2 Burning the BootloaderBootloader via JTAGvia JTAG./Jflash-XSBASE x-boot255

--------------------------------------------------------------------------------XSCALE-R1Copyright (C) 2004 Chhnet Co,. ltd.Support: http://www.hhnet.com.twAutoboot in progress, press any key to stop .Autoboot abortedType "help" to get a list of commandsXSBASE> ……….--------------------------------------------------------------------------------


4.2 Load the Kernel & 4.2 Load the Kernel & FilesystemFilesystemXSBASE> tftp zImage kernelXSBASE> flash kernelXSBASE> tftp rootfs.img rootXSBASE> flash root


4.2 Target Initialization Sequence4.2 Target Initialization Sequence


4.2 Documentation4.2 DocumentationEmbedded Linux Consortium(ELC)http://www.embedded-linux.org

Linux Deviceshttp://www.linuxdevices.com

Embedded Linux journal(ELJ)http://embedded.linuxjournal.com


4.2 Some Linux Kernel Sites4.2 Some Linux Kernel Sites

ftp,httphttp://www.linux-m68k.org/M68k

cvshttp://linuxsh.sourceforge.net/SuperH

cvshttp://www.linux-mips.org/MIPS

ftp,http,…http://penguinppc.org/PowerPC

ftp,synchttp://www.arm.linux.org.uk/developARM

ftp,http,synchttp://www.kernel.org/X86

DownloadurlProcessor


4.2 ARM Linux kernel (Examples)4.2 ARM Linux kernel (Examples)Originalhttp://www.kernel.org

Patch filehttp://www.arm.linux.org.uk


4.2 Additional open source links4.2 Additional open source linksGnu Debugger

http://www.gnu.org/software/gdb/gdb.htmlLinux Test Project - Test coverage of the kernel

http://ltp.sourceforge.net/Linux Trace Toolkit - Acquire and display kernel trace information

http://www.opersys.com/LTT/Guide to porting Linux on new ARM hardware

http://vega.soi.city.ac.uk/~es728/pdf/aleph.pdfGuide to building Linux system from scratch

http://www.opersys.com/quickref.htmlOther useful resources

http://www.debian.orghttp://www.handhelds.org/


4.3 Root 4.3 Root FilesystemFilesystem4.1 4.1 BootloaderBootloader4.2 Embedded Operating System4.2 Embedded Operating System4.3 Root 4.3 Root FilesystemFilesystem4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system


4.3 Root 4.3 Root FilesystemFilesystem TypesTypes

ynnnyRAMDISK/Ext2

nnyyyNFTL/Ext3

nnnyyNFTL/Ext2nnyyyJFFS

nyyyyJFFS2

nynnnCRAMFS

In RAM

CompressPowerDownreliability

AlwaysWriteFilesystem

NFTL:NAND Flash Transfer Layer


4.3 The 4.3 The cramfscramfs FilesystemFilesystemCramfs

The compressed ROM filesystem (or cramfs) A free (GPL'ed) read-only Linux file system designed for simplicity and space-efficiency

Cramfs is used on a number of embedded systems and small devices File size


4.3 The ext2 4.3 The ext2 FilesystemFilesystemAdvantages:

Support up to 4TB memorySupport 1012 bytes long file namesymbolic link : index table speed up

Disadvantages :IDE device design: 1block=512, 1024, 2048…NAND FLASH not support ERASE/WriteNo balance management


4.3 The JFFS2 4.3 The JFFS2 FilesystemFilesystemJFFS2

A log-structured file system designed for use on flash devices in embedded systems.

FeaturesCompression ratio < cramfsBetter than ext2 in (r/w/erase)Power down no crashIf full slow down performance


4.3 The 4.3 The InitrdInitrd (Initial RAM Disk)(Initial RAM Disk)Initrd

The initial ramdiskIt is a temporary file system used by the Linux kernel during boot.A root filesystem

UsageKernel config options

RAM disk supportInitial RAM disk (initrd) support (CONFIG_BLK_DEV_INITRD)

/dev/ram0


4.3 Linux 4.3 Linux FilesystemFilesystemContains system utilities and applications

Busybox for base utilities (http://www.busybox.net/)Need C library – either Glibc or NewlibAdditional utilities such as:

Sysvinit, shells, ftpd, telnet…Graphical windowing system and applications:

X11 environment: http://www.xfree86.org/Microwindows: http://www.microwindows.org/Qt/Qtopia: http://www.trolltech.com

Access from Flash or via NFSFrom Flash can use cramfs, romfs…


4.3 How to Build Root 4.3 How to Build Root FilesystemFilesystem??LddBuildrootfilesystemCopyOthers tools


4.3 4.3 Other toolsOther toolsBusyBox

http://www.busybox.net/Tinylogin

http://tinylogin.busybox.net/Embutils

http://www.fefe.de/embutils/


4.3 4.3 Samba ServerSamba Server(Linux Host) file share with (Windows Host)Setup (Linux Host)

modify /etc/samba/smb.confadd next 2 lines in smb.conf file

[creator]Path=/usr/src/creator


4.3 4.3 NFS (Network File System)NFS (Network File System)(Linux Host) share folder for (Linux Target) mountSetup(Linux host)

edit /etc/exports file with“/user/src/creator/nfs *(rw,no_root_squash)”edit /etc/host.allow file with“portmap:all”build the kernel with NFS supportmake menuconfig


4.3 Linux NFS v4 Architecture4.3 Linux NFS v4 Architecture

Tony .Tony .ReixReix at at bull.netbull.net


4.3 4.3 FilesystemFilesystem Design ToolsDesign ToolsEasyReliableReal-timeOpen and portableExtensible and configurableOpen architectureResource availableComplete functionality


4.3 MTD Support4.3 MTD Support


4.3 RAM/ROM/Flash Chip Drivers4.3 RAM/ROM/Flash Chip Drivers


4.3 Mapping drivers for chip access4.3 Mapping drivers for chip access


4.3 RAMDISK Support4.3 RAMDISK Support


4.3 4.3 FilesystemFilesystem Format Jffs2Format Jffs2


4.3 4.3 CreatCreat FilesystemFilesystem ImageImageSwitch to the File System folder

Filesystem/Use mkfs.jffs2 tool to pack the folder

./mkfs.jffs2 –o rootfs.img –e 0x40000 –r root_XSBase255B –p -l


4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system4.1 4.1 BootloaderBootloader4.2 Embedded Operating System4.2 Embedded Operating System4.3 Root 4.3 Root FilesystemFilesystem4.4 Graphic User Interface of Embedded system4.4 Graphic User Interface of Embedded system


4.4 Future Multi4.4 Future Multi--mode IA Terminalmode IA Terminal


4.4 4.4 Common Features: Graphic User InterfaceCommon Features: Graphic User Interface

3D Graphics

Typical GUI

HP HP iPAQiPAQ rz1710 Navigatorrz1710 Navigator203 MHz S3C2410

7,0 x 1,3 x 11,4 cm

PDA：PPT 8846


4.4 Embedded System GUI More4.4 Embedded System GUI More

www.cybervision.com.tw/

TinyTiny--X GUI Fundamentals X GUI Fundamentals GUI Builder for Linux: the GladeGUI Builder for Linux: the Glade


Glade and GTK+ Glade and GTK+ What is GTK?

GTK+: GIMP Tool KitGIMP: GNU Image Manipulation Program

GTK+ is a set of Graphical User Interface (GUI) toolGTK+ is used to build GUI-based X-window system

What is Glade?Glade is an User Interface Builder for GTK+Glade is a Visual Programming Tool

Similar to the Visual tool VB, Delphi,…


Installation of Installation of ““GladeGlade”” on on XSBase255XSBase255At the /home/Packages/RPM/ folder, type the command:rpm –ivh glade-0.6.4-9.i386.rpm

rpm is the Red-Hat Package Manager-i means install

Command: rpm –ivh glade-0.6.4.9.i386.rpm


Installation of Installation of ““gtk+gtk+--develdevel--1.21.2””At the /home/Packages/RPM/ folder, type the command:rpm –ivh gtk+-devel-1.2.10-39.i386.rpm


Start the GladeStart the GladeApplication Menu:

Command lineglade

1

32

Command: glade


The The Start Windows of Glade Start Windows of Glade When Glade started, the following windows is appear

Project Window

Palette Window Properties Window


The Project WindowThe Project WindowIn Glade, the menu bar contains all commands you need to work with


The Palette WindowThe Palette WindowThe palette contains widgets that can be used to build the user interface.


WinCE Develop EnvironmentWinCE Develop Environment

MPEGMPEG--2 Technologies2 TechnologiesMPEGMPEG--2 Decoder Implementation2 Decoder Implementation


MPEGMPEGMPEG ( Motion Picture Experts Group)

Established in 1988A working group of ISO/IEC in charge of the development of standards for coded representation of digital audio and videoMPEG Standards: System, Video, Audio

ProductsMPEG-1: Video CD and MP3 are basedMPEG-2: Digital Television set top boxes and DVDMPEG-4: multimedia for the fixed and mobile webMPEG-7: for description and search of audio and visual content MPEG-21: the Multimedia Framework

Reference siteshttp://www.mpeg.org/http://www.chiariglione.org/mpeg/


MPEG System SpecificationsMPEG System SpecificationsProvide timing information for:

Buffer managementAudio/video synchronization...

Multiplex bit streams of:Audio, video, data and control

Supporting:Access control (security)Program specific informationDigital storage control...

MPEG-2 system applicationsBroadcast digital TV, Cable digital TV, Interactive TV, DVD, ... etc.


H.264/AVC MPEGH.264/AVC MPEG--4 Applications4 Applications

(資料來源：工研院經資中心經濟部ITIS計畫，2000、資料整理：MIC)


MPEGMPEG--2 Video Compression2 Video CompressionTopics

MPEG Coder/Decoder DiagramProfiles and LevelsFrames, Fields, Pictures (I: Intraframe, P: Predicted, B: Bi-directional)I P B Picture ReorderingPixel PositioningCompression toolsMPEG 2 Video Data Structures

MPEG-2 Toturial Web Sites http://www.bretl.com/mpeghtml/MPEGindex.htm


Basic MPEG Basic MPEG DiagramDiagram

(a) MPEG encoder block diagram

Block of Current Frame

Block of Previous Frame

Vector

Coded Macro-Block

Data

Video signal

+ +

+ -

QDCT

MC

VLC

FrameBuffer

IDCT

IQ

ME

+

+

Motion VectorsCoded

Macro-Block Data

Decoded Video Signal

MC

VLD

FrameMemory

(b) MPEG decoder block diagram

IDCTIQ +BUF


Profiles and Levels of MPEGProfiles and Levels of MPEG--22MPEG-2 is divided into several profiles, the Main profile features are:

4:2:0 chroma sampling formatI, P, and B picturesNon-scalable

Main Profile is subdivided into levelsMP@ML (Main Profile Main Level)MP@HL (Main Profile High Level)ATSC


Levels of Main ProfileLevels of Main ProfileMP@ML (Main Profile Main Level)

Designed with CCIR601 standard for interlaced standard definition digital video in mind.This is the output of current standard definition MPEG-2 decoder chips (DSS).Upper bound:

720 x 576 (PAL) or 720 x 483 (NTSC)30 Hz progressive, 60 Hz interlacedMaximum bit rate is 15 Mbits/s

MP@HL (Main Profile High Level)Upper bounds:

1152 x 1920, 60Hz progressive80 Mbits/s


ATSC Compliant Formats for MPEGATSC Compliant Formats for MPEG--221080 x 1920

1080i: 60 Hz interlaced1080p: 30 Hz progressive

480 x 70460 Hz progressive/interlaced30 Hz progressive

720 x 1280720i: 60 Hz interlaced720p: 30 Hz progressive

480 x 64060 Hz progressive/interlaced30 Hz progressive


ChromaChroma SubsamplingSubsamplingEncoding images by implementing more resolution for luminanceinformation than for color informationTypes of subsampling:(Luma [Y] : Chroma [Cb] : Chroma [Cr])

8:4:4 Y'CbCr4:4:4 Y'CbCr4:4:4 R'G'B' (no subsampling)4:2:24:2:14:1:14:2:04:1:03:1:1


Encoded pictures: I, P, B FramesEncoded pictures: I, P, B FramesI frame

An MPEG picture that is intra coded, i.e. not coded differentially with respect to other pictures

P framePredicted PicturesMacroblocks may be coded with forward prediction from references made from previous I and P pictures or may be intra coded

B frameBi-directionally predicted picturesMacroblocks may be coded with:

Forward/backward prediction from previous/next I or P referencesPrediction from next I or P referenceInterpolated prediction from past and future I or P referencesIntra coded (no prediction)


Frames, FieldsFrames, Fields, Pictures, PicturesGroup of Pictures (GOP)

The group of pictures layer is optionalFirst encoded picture in a GOP is always an I pictureTypical length is 15 pictures with the following structure:

I B B P B B P B B P B B P B BFrame Fields

Non-interlace:2 fields of a frame is encoded together as a frame picture

Interlace:A frame is encoded with two Fields


Mpeg2 Encode ProfilingMpeg2 Encode Profiling

14%Other kernels1%Variable length encoding1%Quantisation1%Predication2%Subsampling9%Discrete cosine transform

71%Motion estimation (dist1)% exe timeOperation


Execution profile of mpeg2decodeExecution profile of mpeg2decode


MPEG2 Encoding TechnologiesMPEG2 Encoding Technologies

http://www.tomshw.it/guides/graphic/20040414/images/mpeg2-encoding.jpg


MPEG2 Decoding TechnologiesMPEG2 Decoding Technologies


FilesystemFilesystem Directories for XSBaseDirectories for XSBase--255 Lab255 Lab

Filesystem folder


Steps of Making MPEGSteps of Making MPEG--2 Decoder for XSBase2 Decoder for XSBase--2525Download the mpeg2_modify.tar.gzUnpack

tar –zxvf mpeg2_modify.tar.gzMake the files

makeDownload the exection file “mpeg2decode” from mpeg2/src/mpeg2dec forder to the XSBASE-255 target


MakefileMakefile ModificationsModificationsmpeg2/src/mpeg2dec/Makefile

CC = arm-linux-gccAdd yuv2rgb.o to OBJ item

Add yuv2rgb.o : yuv2rgb.c config.h global.h mpeg2dec.h relationUse LIBS for hybus installation folder, and use the libX11.a library

mpeg2/src/mpeg2dec/display.cInitialize_Display_Processes()

Use the DefaultVisual and the DefaultDepth to get the related information of the screenExploit the XCreateColormap to create the color mappingNeglect the XMatchVisualInfo

Adjust the color depth of XShmCreateImage to be 16 bitIt needs double space of memory allocation for XCreateImageAt the Initialize_Dither_Matrix(), adding the InitColorDither()In the Dither(), replace the Dither_Frame to the Color16DitherImage()

mpeg2/src/mpeg2dec/yuv2rgb.cThe color space conversion of YUV to RGB (16-bit)


Run mpeg2decoderRun mpeg2decoder$ ./mpeg2decode –o4 –b foreman.m2v

o output format0: YUV1: SIF2: TGA3: PPM4: X115: X11 HiQ


Result in Target LCD DisplayResult in Target LCD DisplayOn the target TFT-LCD panel display, the result of “mpeg2decoder”video is demonstrated.


Example: DIGITAL AV MPEG2 DecoderExample: DIGITAL AV MPEG2 Decoder

www.am.necel.com/common/images/block_d6113x.gif

NEC: uPD61132NEC: uPD61132


MB86V00 / MB86V01 Block Diagram (MPEG4)MB86V00 / MB86V01 Block Diagram (MPEG4)

FujitsuFujitsu


MPEG4: Power Reduction TechniquesMPEG4: Power Reduction TechniquesAlgorithmic Breakthrough to Reduce the Volume of Executions

Scene adaptive-motion estimation algorithm to reduce execution volume to 1/10 or less

Adaptive Clock GatingAutomatic clock gating for each individual internal block according to the operation mode

Complete Hard-wired LogicFull compliant of MPEG-4 simple profile


Comparison of MPEG4 VideoComparison of MPEG4 Video--Codec Power Dissipation Codec Power Dissipation

QCIF 15fps full-duplexcodecARM9 Software Operation drives all internal logic and external SDRAM at 108MHz. (SDRAM:3.3V)Media Accelerator drives all internal logic and external SDRAM at 38.1MHz (SDRAM: 1.8V)Dedicated MPEG4 Codec drives all internal logic and external SDRAM at 13.5MHz (SDRAM: 1.8V)

Fujitsu Microelectronics America, Inc.

chapter4-embedded software architecturestylee/courses/chapter4... · 2008-03-04 · chapter 4...

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