[U-Boot-Users] u-boot 1.1.2 on mpc852t : decrementer exception in interrupt_init()

[gautam borad]

Hi,
    I'm trying to port u-boot-1.1.2 to mpc852t on ep852 board (from 
embedded planet). I'm using RPXClassic as reference.
I only changed the config file rest all is RPXClassic stuff.I've put the 
config file in the end of the post.
First of all the console works only on 2400 even if i set baud rate to 
9600 in my config.h . If i use any other baud rate i get junk on
the screen.
The board gives a "decrementer exception" in interrupt_init() in 
set_msr() in lib_ppc/interrupts.c which takes the code to
 timer_interrupt() and then to timer_interrupt_cpu(). I get all the 
messages till "Hit any key to stop autoboot: 5 " at this point it just 
hangs.
When run through debugger (code warrior) , I accept the message 
(decrementer exception) and continue the execution and all works fine(I 
get the prompt).

The following is the dump ( i sprinkled the code with  *many* printfs)
-------------------------------------------------------------------------------------------------------------------------------------------------------------
U-Boot 1.1.2 (Oct 19 2005 - 18:40:16)

CPU: MPC852TxxZPnn at 50 MHz [40.0...50.0 MHz]
4 kB I-Cache 4 kB D-Cache FEC present
Board: EP852
DRAM: 16 MB

cpu_clk= 50000000 bus_clk = 50000000        
FLASH: Flash addr:ff800000
Device ID :227e227e  16 MB
*** Warning - bad CRC, using default environment

Displaying devices :
In: serial
Out: serial
Err: serial

console_init_r done
decrementer_count = 3125  in hex 0xc35
entering cpm_interrupt_init
entering irq_install_handler with CPMVEC_ERROR
irq_install_handler done
entering irq_install_handler with INTERRUPT
irq_install_handler done
cpm_interrupt_init done
entering set_dec
set_dec done
entering set_msr
*** Timer Interrupt ***                                  //  
timer_interrupt_cpu() in cpu/mpc8xx/interrupts
immr->im_clkrst.car_plprcr = 39a5000            
immr->im_clkrst.car_plprcr = 39a0000
get_dec() = 4294514023l 0xfff91567
Inside timer_interrupt.
decrementer_count = 3125 in hex 0xc35
interrupt init passed.
setting timer
entering initialization from env
initialization from env done.
entering bootfile stuff
bootfile stuff done

Net: FEC ETHERNET

Entering main_loop### main_loop entered: bootdelay=5

### main_loop: bootcmd="tftpboot; setenv bootargs root=/dev/nfs rw 
nfsroot=$(ser
verip):$(rootpath) 
ip=$(ipaddr):$(serverip):$(gatewayip):$(netmask):$(hostname):
:off; bootm"
Hit any key to stop autoboot: 5
--------------------------------------------------------------------------------------------------------------------------------------------------
Why is immr->im_clkrst.car_plprcr = 39a5000 when in config.h i define 
PLPRCR as 0x000A4000 ? Does it matter?

Some of the defines in config.h
#define    RPXClassic_50MHz#define CONFIG_MPC860           1
#define CONFIG_RPXCLASSIC        1
#define CONFIG_MPC852T            1

#define CONFIG_8xx_OSCLK            10000000      
#define CONFIG_8xx_CPUCLK_DEFAULT   50000000       // 50 MHz   
#define CFG_8xx_CPUCLK_MIN          40000000       // 40 MHz
#define CFG_8xx_CPUCLK_MAX          50000000 

#define CFG_LOAD_ADDR        CFG_SDRAM_BASE
#define CFG_IMMR        0xFA200000
#define CFG_SDRAM_BASE    0x00000000
#define CFG_FLASH_BASE    0xFF800000
#define CFG_MONITOR_BASE    CFG_FLASH_BASE

#define CFG_SYPCR    0xFFFFFF89
#define CFG_SIUMCR    0x01000800
#define CFG_RTCSC    (RTCSC_SEC |  RTCSC_ALR | RTCSC_RTE)
#define CFG_PISCR (PISCR_PS | PISCR_PITF | PISCR_PTE)
#define CFG_PLPRCR    0x000A4000                     // is this OK??

#define CFG_SCCR    0x03020800
#define CFG_DER    0x73E67C0F
#define CFG_OR1_PRELIM    0xFF000600
#define CFG_PTA_PER_CLK ((4096 * 32 * 1000) / (4 * 64))

#define CFG_MAMR_PTA    58
#define CFG_MPTPR    MPTPR_PTP_DIV2
#define CFG_MAMR_10COL      0x58803000

All the hard coded values are from the configuration file I got along 
with the board to be used with code warrior and the board works fine 
with that, so they are right.

Thanks in advance.