| ============================================ |
| The Intel Assabet (SA-1110 evaluation) board |
| ============================================ |
| |
| Please see: |
| http://developer.intel.com |
| |
| Also some notes from John G Dorsey <jd5q@andrew.cmu.edu>: |
| http://www.cs.cmu.edu/~wearable/software/assabet.html |
| |
| |
| Building the kernel |
| ------------------- |
| |
| To build the kernel with current defaults:: |
| |
| make assabet_config |
| make oldconfig |
| make zImage |
| |
| The resulting kernel image should be available in linux/arch/arm/boot/zImage. |
| |
| |
| Installing a bootloader |
| ----------------------- |
| |
| A couple of bootloaders able to boot Linux on Assabet are available: |
| |
| BLOB (http://www.lartmaker.nl/lartware/blob/) |
| |
| BLOB is a bootloader used within the LART project. Some contributed |
| patches were merged into BLOB to add support for Assabet. |
| |
| Compaq's Bootldr + John Dorsey's patch for Assabet support |
| (http://www.handhelds.org/Compaq/bootldr.html) |
| (http://www.wearablegroup.org/software/bootldr/) |
| |
| Bootldr is the bootloader developed by Compaq for the iPAQ Pocket PC. |
| John Dorsey has produced add-on patches to add support for Assabet and |
| the JFFS filesystem. |
| |
| RedBoot (http://sources.redhat.com/redboot/) |
| |
| RedBoot is a bootloader developed by Red Hat based on the eCos RTOS |
| hardware abstraction layer. It supports Assabet amongst many other |
| hardware platforms. |
| |
| RedBoot is currently the recommended choice since it's the only one to have |
| networking support, and is the most actively maintained. |
| |
| Brief examples on how to boot Linux with RedBoot are shown below. But first |
| you need to have RedBoot installed in your flash memory. A known to work |
| precompiled RedBoot binary is available from the following location: |
| |
| - ftp://ftp.netwinder.org/users/n/nico/ |
| - ftp://ftp.arm.linux.org.uk/pub/linux/arm/people/nico/ |
| - ftp://ftp.handhelds.org/pub/linux/arm/sa-1100-patches/ |
| |
| Look for redboot-assabet*.tgz. Some installation infos are provided in |
| redboot-assabet*.txt. |
| |
| |
| Initial RedBoot configuration |
| ----------------------------- |
| |
| The commands used here are explained in The RedBoot User's Guide available |
| on-line at http://sources.redhat.com/ecos/docs.html. |
| Please refer to it for explanations. |
| |
| If you have a CF network card (my Assabet kit contained a CF+ LP-E from |
| Socket Communications Inc.), you should strongly consider using it for TFTP |
| file transfers. You must insert it before RedBoot runs since it can't detect |
| it dynamically. |
| |
| To initialize the flash directory:: |
| |
| fis init -f |
| |
| To initialize the non-volatile settings, like whether you want to use BOOTP or |
| a static IP address, etc, use this command:: |
| |
| fconfig -i |
| |
| |
| Writing a kernel image into flash |
| --------------------------------- |
| |
| First, the kernel image must be loaded into RAM. If you have the zImage file |
| available on a TFTP server:: |
| |
| load zImage -r -b 0x100000 |
| |
| If you rather want to use Y-Modem upload over the serial port:: |
| |
| load -m ymodem -r -b 0x100000 |
| |
| To write it to flash:: |
| |
| fis create "Linux kernel" -b 0x100000 -l 0xc0000 |
| |
| |
| Booting the kernel |
| ------------------ |
| |
| The kernel still requires a filesystem to boot. A ramdisk image can be loaded |
| as follows:: |
| |
| load ramdisk_image.gz -r -b 0x800000 |
| |
| Again, Y-Modem upload can be used instead of TFTP by replacing the file name |
| by '-y ymodem'. |
| |
| Now the kernel can be retrieved from flash like this:: |
| |
| fis load "Linux kernel" |
| |
| or loaded as described previously. To boot the kernel:: |
| |
| exec -b 0x100000 -l 0xc0000 |
| |
| The ramdisk image could be stored into flash as well, but there are better |
| solutions for on-flash filesystems as mentioned below. |
| |
| |
| Using JFFS2 |
| ----------- |
| |
| Using JFFS2 (the Second Journalling Flash File System) is probably the most |
| convenient way to store a writable filesystem into flash. JFFS2 is used in |
| conjunction with the MTD layer which is responsible for low-level flash |
| management. More information on the Linux MTD can be found on-line at: |
| http://www.linux-mtd.infradead.org/. A JFFS howto with some infos about |
| creating JFFS/JFFS2 images is available from the same site. |
| |
| For instance, a sample JFFS2 image can be retrieved from the same FTP sites |
| mentioned below for the precompiled RedBoot image. |
| |
| To load this file:: |
| |
| load sample_img.jffs2 -r -b 0x100000 |
| |
| The result should look like:: |
| |
| RedBoot> load sample_img.jffs2 -r -b 0x100000 |
| Raw file loaded 0x00100000-0x00377424 |
| |
| Now we must know the size of the unallocated flash:: |
| |
| fis free |
| |
| Result:: |
| |
| RedBoot> fis free |
| 0x500E0000 .. 0x503C0000 |
| |
| The values above may be different depending on the size of the filesystem and |
| the type of flash. See their usage below as an example and take care of |
| substituting yours appropriately. |
| |
| We must determine some values:: |
| |
| size of unallocated flash: 0x503c0000 - 0x500e0000 = 0x2e0000 |
| size of the filesystem image: 0x00377424 - 0x00100000 = 0x277424 |
| |
| We want to fit the filesystem image of course, but we also want to give it all |
| the remaining flash space as well. To write it:: |
| |
| fis unlock -f 0x500E0000 -l 0x2e0000 |
| fis erase -f 0x500E0000 -l 0x2e0000 |
| fis write -b 0x100000 -l 0x277424 -f 0x500E0000 |
| fis create "JFFS2" -n -f 0x500E0000 -l 0x2e0000 |
| |
| Now the filesystem is associated to a MTD "partition" once Linux has discovered |
| what they are in the boot process. From Redboot, the 'fis list' command |
| displays them:: |
| |
| RedBoot> fis list |
| Name FLASH addr Mem addr Length Entry point |
| RedBoot 0x50000000 0x50000000 0x00020000 0x00000000 |
| RedBoot config 0x503C0000 0x503C0000 0x00020000 0x00000000 |
| FIS directory 0x503E0000 0x503E0000 0x00020000 0x00000000 |
| Linux kernel 0x50020000 0x00100000 0x000C0000 0x00000000 |
| JFFS2 0x500E0000 0x500E0000 0x002E0000 0x00000000 |
| |
| However Linux should display something like:: |
| |
| SA1100 flash: probing 32-bit flash bus |
| SA1100 flash: Found 2 x16 devices at 0x0 in 32-bit mode |
| Using RedBoot partition definition |
| Creating 5 MTD partitions on "SA1100 flash": |
| 0x00000000-0x00020000 : "RedBoot" |
| 0x00020000-0x000e0000 : "Linux kernel" |
| 0x000e0000-0x003c0000 : "JFFS2" |
| 0x003c0000-0x003e0000 : "RedBoot config" |
| 0x003e0000-0x00400000 : "FIS directory" |
| |
| What's important here is the position of the partition we are interested in, |
| which is the third one. Within Linux, this correspond to /dev/mtdblock2. |
| Therefore to boot Linux with the kernel and its root filesystem in flash, we |
| need this RedBoot command:: |
| |
| fis load "Linux kernel" |
| exec -b 0x100000 -l 0xc0000 -c "root=/dev/mtdblock2" |
| |
| Of course other filesystems than JFFS might be used, like cramfs for example. |
| You might want to boot with a root filesystem over NFS, etc. It is also |
| possible, and sometimes more convenient, to flash a filesystem directly from |
| within Linux while booted from a ramdisk or NFS. The Linux MTD repository has |
| many tools to deal with flash memory as well, to erase it for example. JFFS2 |
| can then be mounted directly on a freshly erased partition and files can be |
| copied over directly. Etc... |
| |
| |
| RedBoot scripting |
| ----------------- |
| |
| All the commands above aren't so useful if they have to be typed in every |
| time the Assabet is rebooted. Therefore it's possible to automate the boot |
| process using RedBoot's scripting capability. |
| |
| For example, I use this to boot Linux with both the kernel and the ramdisk |
| images retrieved from a TFTP server on the network:: |
| |
| RedBoot> fconfig |
| Run script at boot: false true |
| Boot script: |
| Enter script, terminate with empty line |
| >> load zImage -r -b 0x100000 |
| >> load ramdisk_ks.gz -r -b 0x800000 |
| >> exec -b 0x100000 -l 0xc0000 |
| >> |
| Boot script timeout (1000ms resolution): 3 |
| Use BOOTP for network configuration: true |
| GDB connection port: 9000 |
| Network debug at boot time: false |
| Update RedBoot non-volatile configuration - are you sure (y/n)? y |
| |
| Then, rebooting the Assabet is just a matter of waiting for the login prompt. |
| |
| |
| |
| Nicolas Pitre |
| nico@fluxnic.net |
| |
| June 12, 2001 |
| |
| |
| Status of peripherals in -rmk tree (updated 14/10/2001) |
| ------------------------------------------------------- |
| |
| Assabet: |
| Serial ports: |
| Radio: TX, RX, CTS, DSR, DCD, RI |
| - PM: Not tested. |
| - COM: TX, RX, CTS, DSR, DCD, RTS, DTR, PM |
| - PM: Not tested. |
| - I2C: Implemented, not fully tested. |
| - L3: Fully tested, pass. |
| - PM: Not tested. |
| |
| Video: |
| - LCD: Fully tested. PM |
| |
| (LCD doesn't like being blanked with neponset connected) |
| |
| - Video out: Not fully |
| |
| Audio: |
| UDA1341: |
| - Playback: Fully tested, pass. |
| - Record: Implemented, not tested. |
| - PM: Not tested. |
| |
| UCB1200: |
| - Audio play: Implemented, not heavily tested. |
| - Audio rec: Implemented, not heavily tested. |
| - Telco audio play: Implemented, not heavily tested. |
| - Telco audio rec: Implemented, not heavily tested. |
| - POTS control: No |
| - Touchscreen: Yes |
| - PM: Not tested. |
| |
| Other: |
| - PCMCIA: |
| - LPE: Fully tested, pass. |
| - USB: No |
| - IRDA: |
| - SIR: Fully tested, pass. |
| - FIR: Fully tested, pass. |
| - PM: Not tested. |
| |
| Neponset: |
| Serial ports: |
| - COM1,2: TX, RX, CTS, DSR, DCD, RTS, DTR |
| - PM: Not tested. |
| - USB: Implemented, not heavily tested. |
| - PCMCIA: Implemented, not heavily tested. |
| - CF: Implemented, not heavily tested. |
| - PM: Not tested. |
| |
| More stuff can be found in the -np (Nicolas Pitre's) tree. |
