writing CCSR_BAR register for relocation?

2 messages, 1 author, 2006-07-28 · open the first message on its own page

writing CCSR_BAR register for relocation?

From: Parav Pandit <hidden>
Date: 2006-07-28 11:28:04

Hi,

I am newbie to MPC8555, PowerPC family and u-boot.
Please guide me.

1. How can I read/write registers from the u-boot
similar to md/mm command? Basically I want to
read/write CCSR_BAR from the u-boot.

2. How can I read/write CCSRBAR register value from my
assembly program?
mfspr.mtspr ??? what is the register name??

3. By changing the default value of 0xFF70:0000 to
0xE000:0000 is sufficient to relocate the 1MB block or
anything else is also required?

4. I look at the u-boot code for tqm85xx, 8555cds, and
8555ads series of boards and it does something with
TLB.
I don't understand why it modifies the TLB registers
whose purpose is only for the performance improvement?
Or we can use the TLB for something else also?

Regards,
Parav Pandit


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 

Re: writing CCSR_BAR register for relocation?

From: Parav Pandit <hidden>
Date: 2006-07-28 12:01:25

I have read the MPC8555 RF.
section 4.3.1.1 says that CCSRBAR is points to itself.

Checked by the md command in u-boot.
it shows the same results, FF70:0000.

It shows the FF704600 also at that address for all the
addresses it shows the same content as address.

If this is the case, how come the u-boot works on
serial port? It should show some other value for the
configured devices such as serial port at least.

or somethign is missing on my side...

Regards,
Parav Pandit

--- Parav Pandit <paravpandit@yahoo.com> wrote:
Hi,

I am newbie to MPC8555, PowerPC family and u-boot.
Please guide me.

1. How can I read/write registers from the u-boot
similar to md/mm command? Basically I want to
read/write CCSR_BAR from the u-boot.

2. How can I read/write CCSRBAR register value from
my
assembly program?
mfspr.mtspr ??? what is the register name??

3. By changing the default value of 0xFF70:0000 to
0xE000:0000 is sufficient to relocate the 1MB block
or
anything else is also required?

4. I look at the u-boot code for tqm85xx, 8555cds,
and
8555ads series of boards and it does something with
TLB.
I don't understand why it modifies the TLB registers
whose purpose is only for the performance
improvement?
Or we can use the TLB for something else also?

Regards,
Parav Pandit


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam
protection around 
http://mail.yahoo.com 
_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help