[coreboot] r5402 ...

[Joseph Smith]

On 04/11/2010 10:23 AM, Stefan Reinauer wrote:
> Hi,
>>>> + PRINTK_DEBUG(" Reading RAM at 0x%08x =>  0x%08x\n", (dimm_start *
>>>> 32 * 1024 * 1024), read32(dimm_start * 32 * 1024 * 1024));
>>>>
>>>>
>>> There is a good chance that this read does not happen unless debugging
>>> is enabled. Is that on purpose?
>>> It would be clearer to pull this out of the PRINTK like this:
>>>
>>> #if CONFIG_RAM_DEBUG
>>> u32 value = read32(dimm_start * 32 * 1024 * 1024);
>>> PRINTK_DEBUG(" Reading RAM at 0x%08x =>  0x%08x\n", (dimm_start * 32
>>> * 1024 * 1024), value);
>>> #endif
>>>
>>
>> Yes that is on purpose. I guess I could use a preprocessing directive,
>> but I thought that was the point of the macro.
> well yes and no. There is no guarantee that the read is executed even if
> CONFIG_RAM_DEBUG is on. So it is not side effect free.
>
Hmm, so a preprocessing directive will cure this side effect?
>
>
>> Performing dummy read/write
>> Reading RAM at 0x20000000 =>  0xf5ba55aa
>> Writing RAM at 0x20000000<= 0x55aa55aa
>> Reading RAM at 0x20000000 =>  0x55aa55aa
>
> So this read/write is only for debugging? It will break suspend/resume,
> should you intend to go for that.
>
This is how original bios does it. raminit is run again on resume? That 
seems strange...

-- 
Thanks,
Joseph Smith
Set-Top-Linux
www.settoplinux.org