Problem of PowerPc 82xx when using smc

hellohello hellohello008 at 163.com
Sat May 22 12:51:56 EST 2010


> Newer kernels support dynamically allocating this parameter RAM.  Older 
> kernels use whatever u-boot chose.
> 
> Why do you want to set it to a particular address?

There should be some code to set SMC1_BASE to the 0x87FC offset of the DPRAM, whatever SMC1_BASE is fixed or dynamically allocated .

My kernel is 2.6.25, this SMC1_BASE value can be transferred to  kernel by dts tree, but I have not find the code to set it to  0x87FC offset of the DPRAM. Or there is another way to solve it ?



----- Original Message ----- 
From: "Scott Wood" <scottwood at freescale.com>
To: "hellohello" <hellohello008 at 163.com>
Cc: <linuxppc-dev at lists.ozlabs.org>
Sent: Saturday, May 22, 2010 1:28 AM
Subject: Re: Problem of PowerPc 82xx when using smc


> On 05/20/2010 10:33 PM, hellohello wrote:
>>> No, it shouldn't -- rx_bd_base is of type "cbd_t *", so the multiplication
>>> already happens as part of pointer arithmetic.
>> ---Yes, you are right. I made a basic mistake.
>>
>> But now I have another question.
>> The SMC1 params can be relocated to any offset of the DPRAM on a 64 byte boundary, not as the SCC1, which must be  at 0x8000 offset of the DPRAM.
>> The SMC1 params base is set at 0x87FC offset of the DPRAM.
>>
>> So if  I want SMC1 params start at  0x200 in DPRAM  , I should set 0x200 to the 0x87FC offset of the DPRAM.
>> I have see this code in u-boot, but I can not find this code in neither cpm_uart_cpm2.c nor cpm_uart_core.c.
>>
>> Should I add these code to  cpm_uart_core.c?
> 
> Newer kernels support dynamically allocating this parameter RAM.  Older 
> kernels use whatever u-boot chose.
> 
> Why do you want to set it to a particular address?
> 
> -Scott
>


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