Embedded Linux Workshop
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Lib C:
 - glibc
 - eglibc (more configuration, may not be up to date)
 - uClibc (adapted to uCLinux, use the old linux threads,
           shared memory?, no real time stuff, good for less
           than 60MB storage)

Choosing a toolchain :
 - for an ARM A-8, an armv4 compiler will not be optimized
   use armv7t
 - good libc
 - up to date
 - good support or community
 - bonus: dev tools
 - bonus: cross compiled libs
 - exemple: codesorcery g++, denx eldk, angstrom, debian...
 - or do it yourself: buildroot, openembedded, ltib...
 - commercial: montavista, timesys, windriver, lynux
               (they are not really up to date
                and do not offer many packages)
 - TRAP: toolchains shipped with board are often very bad

Debugging:
 - provided by the toochain
 - libraries should have debug symbols
 - profiler tracers

Bootloader:
 - set up sdram controler
 - map memory
 - set processor modes and feats
 - load kernel
 - there can be a pre-bootloader (on hardware)
 - Das U-Boot (popular)
 - Redboot

Passing hardware info to the kernel on ARM:
 - R1: machine umber
 - R2: pointer to ATAGS list

U-Boot:
nand read  <place to put the image in mem>
           <place to read on nand>
           <size of image>

setenv bootcmd ...

Kernel:
 - think about using long term support kernels
 - private BSPs are often not up to date
 - arch -> chip -> board
 - use make oldconfig
 - do not use modules unless necessary
 - the order of modules loading can be used to reduce boot t
 - .config -> autoconf.h
 - export cross compile variables
 - zImage or uImage
 - quiet !=! debug

User Space:
 - do not use udev when speed is needed
 - ubfs is cool (yaffs2 too but not mainline)


See the slides...