hi there,
first of all, let me just thank anyone who has taken the time to read this post ... and also i apologise for being naivety, i'm just crossing over to linux from unix :>
needless to say, i'm kinda at the end of my tether trying to figure out what the heck is going on ... so let me explain my problem
what i'm trying to do is run montavista linux on an embedded PmPPC7448 PowerPC-Based processor pmc module ... the board is diskless, a compressed kernel image and filesystem image is resident in flash ... i want to boot the kernel (ok) and mount the fs as a ramdisk from sdram (this is my problem!)
my linux kernel is 2.6.10 and the artesyn board has the following configuration,
CPU: MPC7448 v2.0 @ 999.999 MHz Board: PM/PPC-7448 BusHz: 133333333 I2C: ready DRAM: DDR SDRAM in slot 0 ECC 1024 MB FLASH: [64MB@e8000000] 64 MB
my embedded physical memory map is as follows,
SDRAM - 0000,0000 to 3fff,ffff FLASH - e800,0000 to ec00,0000
the bootloader is the board manufacturers version of u-boot with slimmed down functionality
the FLASH memory is partitioned as follows,
e800,0000 - e810,0000 bootloader image e810,0000 - e828,0000 compressed linux kernel image e828.0000 - ea08,0000 compressed filesystem image
the filesystem image (ext2) was prepared with the uboot "mkimage" tool in order to incorporate the appropriate header data for u-boot to interpret the image as a (gzip) compressed ramdisk
i've provided a script of my kernel boot below, and as you will see, the kernel fails to mount the root fs. ramdisk support is built into the kernel and i use the uboot command "bootm " to boot
it seems to me that the ramdisk driver goes start, creates 16 devices (/dev/ram0 to /dev/ram15 i guess) but it fails to mount the ramdisk. its almost as if the kernel has not associated the passed to uboot with the /dev/ram ... ?
i can also see that uboot has loaded the ramdisk and relocated it at the top of sdram, but can the kernel address this ?? from the script it logs that the total memory is 768MB and not 1024MB (1GB) ... do i need to use the kernel prompt argument mem= ?
are there any kernal build CONFIG_ issues that i need to address? the kernel is statically linked with NO modules
i'm confused as to how the initrd is associated with the /dev/ram device ... how does the bootloader pass the address of the ramdisk to the kernel?
do i need a separate initrd image in the linux /boot directory? and compile this into the kernel? hmmmm
what am i doing wrong? the target platform is diskless, so i need the kernel to boot from flash with a root fs also located in flash. i've successfully booted over nfs, but now i've hit a brick wall (ugh)
if anybody can help me then please, please please do!!
many thanks,
-bill
***************************** here is the boot script *****************************U-Boot 0.4.0 (Jul 14 2005 - 16:09:18)1.0
CPU: MPC7448 v2.0 @ 999.999 MHz Board: PM/PPC-7448 BusHz: 133333333 I2C: ready DRAM: DDR SDRAM in slot 0 ECC (Clearing..) 1024 MB FLASH: [64MB@e8000000] 64 MB PCI: Bus Host
Waiting For EREADY ('q' to exit w/o enum).
00 02 10b5 9656 0680 ffDiags Mem: PASSED Diags I2C: PASSED Diags Flash: PASSED
Ser#: 1020 Mon: Resides 0x40000000 - 0x3ff359c0 BtDev: Soldered Flash DCach: on (WriteThrough) ICach: on L2Che: on (WriteThrough) Net: portdbg, porta, portb Hit any key to stop autoboot: 0
PM/PPC-7448(1.0)=>printenv baudrate=9600 cachemode=write clearmem=on dcache=on ecc=on enumerate=on eready=on icache=on l2cache=on model=PM/PPC-7448 powerondiags=on eth_portb=auto eth_frontpanel=auto console=frontpanel ecc_1bit_report=off serial#=1020 netmask=255.255.255.0 serverip=192.168.1.114 gatewayip=192.168.1.1 bootdelay=2 tftpport=69 loadaddr=0x400000 rootpath=/opt/montavista/pro/devkit/ppc/74xx/target bootfile=uImage.quad0 hostname=pico-ppc3 ipaddr=192.168.1.103 ethport=porta eth_porta=100t_full nfs_bootargs=setenv bootargs console=ttyMM0,9600 root=/dev/nfs rw nfsroot=$(rootpath) ip=$(ipaddr):$(serverip)::$(netmask):$(hostname)::off devfs=mount nfs_bootcmd=dhcp ; run nfs_bootargs ; bootm bootcmd=run nfs_bootcmd ffs_bootcmd=run ffs_bootargs ; bootm e8100000 e8280000 ffs_bootargs=setenv bootargs console=ttyMM0,9600 ramdisk_size=7167 root=/dev/ram0 rw rootfstype=ext2 panic=10 initrd=e8280000,6ffc00 stdin=serial stdout=serial stderr=serial bootargs=console=ttyMM0,9600 ramdisk_size=7167 root=/dev/ram0 rw rootfstype=ext2 panic=10 initrd=e8280000,6ffc00
Environment size: 1043/1492 bytes
PM/PPC-7448(1.0)=>run ffs_bootcmd ## Booting image at e8100000 ... Image Name: Linux-2.6.10_dev-pmppc7448-mod Created: 2006-03-21 11:23:51 UTC Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 1123720 Bytes = 1.1 MB Load Address: 00000000 Entry Point: 00000000 Verifying Checksum ... OK Uncompressing Kernel Image ... OK ## Loading RAMDisk Image at e8280000 ... Image Name: ram disk Created: 2006-03-21 10:53:06 UTC Image Type: PowerPC Linux RAMDisk Image (gzip compressed) Data Size: 2398340 Bytes = 2.3 MB Load Address: e8280000 Entry Point: e8280000 Verifying Checksum ... OK Loading Ramdisk to 3fd2b000, end 3ff74884 ... OK Total memory = 768MB; using 2048kB for hash table (at c0400000) Linux version 2.6.10_dev-pmppc7448-mod (nkw@tobermoray) (gcc version 3.4.3 (MontaVista 3.4.3-25.0.70.0501961 2005-12-18)) #65 Tue Mar 21 11:23:48 GMT
2006 Calling the enumerate pci bus Code PCI Autoconfig: Found Bus 0, Device 2, Function 0 PCI Autoconfig: BAR 0x10, Mem size=0x200, address=0x9ffffe00 PCI Autoconfig: BAR 0x14, I/O, size=0x100, address=0x3ffff00 PCI Autoconfig: BAR 0x18, Mem size=0x400000, address=0x9f800000 PCI Autoconfig: BAR 0x1c, Mem size=0x400000, address=0x9f400000 Artesyn Communication Products, LLC - PmPPC7447 Configured for Quad Slot 0 Built 1 zonelists Kernel command line: console=ttyMM0,9600 ramdisk_size=7167 root=/dev/ram0 rw rootfstype=ext2 panic=10 initrd=e8280000,6ffc00 PID hash table entries: 4096 (order: 12, 65536 bytes) time_init: decrementer frequency = 33.333333 MHz Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) Memory: 774400k available (1796k kernel code, 544k data, 116k init, 0k highmem) Mount-cache hash table entries: 512 (order: 0, 4096 bytes) spawn_desched_task(00000000) desched cpu_callback 3/00000000 ksoftirqd started up. desched cpu_callback 2/00000000 desched thread 0 started up. NET: Registered protocol family 16 PCI: Probing PCI hardware Thermal assist unit not available JFFS version 1.0, (C) 1999, 2000 Axis Communications AB JFFS2 version 2.2. (C) 2001-2003 Red Hat, Inc. Generic RTC Driver v1.07 Serial: MPSC driver $Revision: 1.00 $ ttyMM0 at MMIO 0xf1062000 (irq = 36) is a MPSC ttyMM1 at MMIO 0xf1068000 (irq = 38) is a MPSC io scheduler noop registered io scheduler anticipatory registered io scheduler deadline registered io scheduler cfq registered RAMDISK driver initialized: 16 RAM disks of 7167K size 1024 blocksize loop: loaded (max 8 devices) pcnet32.c:v1.30i 06.28.2004 snipped-for-privacy@alpha.franken.de MV-643xx 10/100/1000 Ethernet Driver eth0: port 0 with MAC address 00:80:f9:81:00:14 eth0: RX NAPI Enabled eth1: port 1 with MAC address 00:80:f9:82:00:14 eth1: RX NAPI Enabled eth2: port 2 with MAC address 00:80:f9:83:00:14 eth2: RX NAPI Enabled elevator: using anticipatory as default io scheduler physmap flash device: 4000000 at e8000000 phys_mapped_flash: Found 2 x16 devices at 0x0 in 32-bit bank Intel/Sharp Extended Query Table at 0x0031 Using buffer write method cfi_cmdset_0001: Erase suspend on write enabled cmdlinepart partition parsing not available RedBoot partition parsing not available Using physmap partition definition Creating 6 MTD partitions on "phys_mapped_flash": 0x00000000-0x00100000 : "Monitor" 0x00100000-0x00280000 : "Primary Kernel" 0x00280000-0x02080000 : "Primary Filesystem" 0x02080000-0x02200000 : "Secondary Kernel" 0x02200000-0x04000000 : "Secondary Filesystem" 0x00100000-0x04000000 : "User FLASH" NET: Registered protocol family 2 IP: routing cache hash table of 8192 buckets, 64Kbytes TCP: Hash tables configured (established 262144 bind 65536) NET: Registered protocol family 1 NET: Registered protocol family 17 Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0) Rebooting in 10 seconds..rhubarb!!