help me on 2.6.15 kernel on MPC850

[gshan <gshan@alcatel-lucent.com>]

Hey Guys,

The CPU was spinning when executing in head_8xx.S::initial_mmu. I have 
located the instruction that cause the spinning through on-board leds. 
Do you have any ideas?

#ifdef CONFIG_8xx_COPYBACK
       mtspr   SPRN_DC_CST, r8                                     <<< 
The spinning was caused by this instruction
#endif

#else
       /*
        * For a debug option, I left this here to easily enable
        * the write through cache mode
        */
       lis     r8, DC_SFWT@h
       mtspr   SPRN_DC_CST, r8
       lis     r8, IDC_ENABLE@h
       mtspr   SPRN_DC_CST, r8
#endif

       blr

-----------------------------

The output from u-boot:

=> tftp 0x100000 uImage
Using SCC ETHERNET device
TFTP from server 90.0.0.3; our IP address is 90.0.0.50
Filename 'uImage'.
Load address: 0x100000
Loading: #################################################################
        #################################################################
        ###################################
done
Bytes transferred = 844738 (ce3c2 hex)
=> bootm
## Booting image at 00100000 ...
  Image Name:   Linux-2.6.15
  Created:      2007-04-07  17:25:29 UTC
  Image Type:   PowerPC Linux Kernel Image (gzip compressed)
  Data Size:    844674 Bytes = 824.9 kB
  Load Address: 00000000
  Entry Point:  00000000
  Verifying Checksum ... OK
  Uncompressing Kernel Image ... OK               <<< The CPU is 
spinning then

-----------------------------

The hardware, bootloader, linux I'm using:

1) MPC850, 1KB DCache + 2KB ICache
2) u-boot 1.1.4 ( Data Cache is turned off all the way, but instruction 
cache is always on)
3) ppclinux 2.6.15

Thanks,
Gavin