[U-Boot-Users] Command "dcache on" for MPC850 isn't valid

[U-Boot-Users] Command "dcache on" for MPC850 isn't valid

[gshan]

Hi All,

I got a problem recently and have to send this mail for resolution. The 
configuration I'm using:

CPU:     MPC8xx
U-boot: 1.1.4
Linux   : 2.6.15
ELDK  : 4.0

As everyone knew, uboot for MPC850 didn't turn on data cache, but 
instruction cache is on. In order to test data cache, I added 
CFG_CMD_CACHE  for CONFIG_COMMANDS. However, the CPU is spinning once I 
issue command "dcache on".

Any ideas on this?

Thanks,
Gavin

[U-Boot-Users] Command "dcache on" for MPC850 isn't valid

[Wolfgang Denk]

In message <461C6D9A.7010001@alcatel-lucent.com> you wrote:
> 
> As everyone knew, uboot for MPC850 didn't turn on data cache, but 

Yes, and for a very good reason, which is explained in detail in the
README.

> instruction cache is on. In order to test data cache, I added 
> CFG_CMD_CACHE  for CONFIG_COMMANDS. However, the CPU is spinning once I 
> issue command "dcache on".
> 
> Any ideas on this?

Read the README.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH, HRB 165235 Munich, CEO: Wolfgang Denk
Office:  Kirchenstr. 5,       D-82194 Groebenzell,            Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"If you'll excuse me a minute, I'm going to have a cup of coffee."
- broadcast from Apollo 11's LEM, "Eagle", to Johnson  Space  Center,
Houston July 20, 1969, 7:27 P.M.

[U-Boot-Users] Command "dcache on" for MPC850 isn't valid

[gshan]

Denk,

Thanks for your quick response. But linux kernel need to turn on data 
cache at head_8xx.S::initial_mmu.

Thanks,
Gavin

Wolfgang Denk wrote:
> In message <461C6D9A.7010001@alcatel-lucent.com> you wrote:
>   
>> As everyone knew, uboot for MPC850 didn't turn on data cache, but 
>>     
>
> Yes, and for a very good reason, which is explained in detail in the
> README.
>
>   
>> instruction cache is on. In order to test data cache, I added 
>> CFG_CMD_CACHE  for CONFIG_COMMANDS. However, the CPU is spinning once I 
>> issue command "dcache on".
>>
>> Any ideas on this?
>>     
>
> Read the README.
>
> Best regards,
>
> Wolfgang Denk
>
>   

[U-Boot-Users] Command "dcache on" for MPC850 isn't valid

[Wolfgang Denk]

In message <461D9765.7060502@alcatel-lucent.com> you wrote:
> 
> Thanks for your quick response. But linux kernel need to turn on data 
> cache at head_8xx.S::initial_mmu.

Yes. So what?

PLease don't top post / full quote. Read
http://www.netmeister.org/news/learn2quote.html

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH, HRB 165235 Munich, CEO: Wolfgang Denk
Office:  Kirchenstr. 5,       D-82194 Groebenzell,            Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Wenn Du ein' weise Antwort verlangst, Mu?t Du vern?nftig fragen.
                                                -- Goethe, Invektiven