Porting Linux Linux onto the Puppeteer SA1110

The Puppeteer board –SA1110 CPU –SMSC LAN91C96I ethernet –8 Mb Flash Intel 28F320C3 Boot block flash –32 Mb DRAM –Altera FPGA 6k –Xilinks CPLD XCR3064A

Selecting an OS Lots of choices –NETBSD gcc problems – good documentation –Ecos Modular rt system –Linux Various commercial versions –Montavista, Yellowdog, blue cat Distributions –Redhat, Debian Uclinux –Arm has an MMU Build your own! – >

Building the cross compiler Using gcc –Going to 3.3 for 2.6.n kernels Binutils –X Building own –There are lots of toolchains around!

Selecting a library Selecting a library for an embedded system requires care. –Glibc GNU standard – too large –Newlib Good for embedded board without an OS/linux –Uclibc Doesn’t need Uclinux – small & well supported Good gcc support

The native BSP Fairly large problem for porting –Supports VxWorks –Specialised command set – no debug! –Uses COFF/MSbin –Does use standard tftp –No documentation Had to create several tools –Elf2bin –Eloadsvr –elf2data

Building the kernel SA1110 is well supported –Changes to board specifics Linux/arch/arm/head.s Serial port code esp. in linux/include

Creating a rootfs Need to create rootfs on host –dd to create empty 8mb file –Mkfs.ext2 on it –Mount –o loop –Create /dev /etc et al –Type carefully! Needed converting into MSbin format – yuk!

Busybox & tiny login Rather than build each tool, busybox and tinylogin were used Very good set of utilities –Works well with uclibc –Easy to configure Require some full scale tools –TCP/IP tools Weird busybox error!

TCP/IP& NFS Had to port the SMC9194.c driver for board –Find the chip! –Re-write low level access routine –FPGA interrupt handling routines Debugging! –The importance of ARP NFS –Requires some extra library support zlib –Seems to work –NFS mounted root fs doesn’t work, yet!

Remote debugging with GDB Using gdb version 6 Seems to work well with uclibc untested

MTD flash devices MTD is not supposed to be in sync with kernel – seemed fine Using CFI –Under 2.4.n have to put partitions into map file sa1110-flash.c 7MB available –Boot block? Choice of file systems Weird mtd MAC address problem

I 2 c and eeprom Due to the MTD/MAC problem I ported some transpond code for I 2 c & eeprom to read the nv data Works in smc driver! I 2 c implemented as a linux driver – not tested This is straying towards bsp/bios functionality

Das Uboot Needs a new boot strap – lots of choice –Redboot, blob, angelboot, Using Uboot –Well supported, small, modular Need to write FPGA support code Need I 2 c code How to install –Jtag? ICE?