From mboxrd@z Thu Jan  1 00:00:00 1970
From: Atsuo Igarashi <atsuo_igarashi@tripeaks.co.jp>
Date: Thu, 18 Sep 2008 15:06:27 +0900
Subject: [U-Boot] [PATCH v2] Add support for KMC KZM-ARM11-01 board
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	<20080909065755.B7EC6248A6@gemini.denx.de>
	<48C773E2.1000309@tripeaks.co.jp>
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Dear Wolfgang Denk,

>>> +/*
>>> + * The MX31ADS board seems to have a hardware "peculiarity" 
>>> confirmed under
>>> + * U-Boot, RedBoot and Linux: the ethernet Rx signal is reaching the 
>>> CS8900A
>>> + * controller inverted. The controller is capable of detecting and 
>>> correcting
>>> + * this, but it needs 4 network packets for that. Which means, at 
>>> startup, you
>>> + * will not receive answers to the first 4 packest, unless there 
>>> have been some
>>> + * broadcasts on the network, or your board is on a hub. Reducing 
>>> the ARP
>>> + * timeout from default 5 seconds to 200ms we speed up the initial TFTP
>>> + * transfer, should the user wish one, significantly.
>>> + */
>>> +#define CONFIG_ARP_TIMEOUT    200UL
>>
>>
>> Is this really needed on your hardware, too? I doubt it.
>>
> 
> Probably, this is not needed.
> I'll remove this.
> 

In our board which has SMC9118 controller, it seems that it needs a few hundred
milliseconds wait after the initialization. So this is needed.
I'll modify only these comment.


>>> +/* Address and size of Redundant Environment Sector    */
>>> +#define CFG_ENV_OFFSET_REDUND    (CFG_ENV_OFFSET + CFG_ENV_SIZE)
>>> +#define CFG_ENV_SIZE_REDUND    CFG_ENV_SIZE
>>> +
>>> +/* S29WS256N NOR flash has 4 32KiB small sectors at the beginning 
>>> and at the end.
>>> + * The rest of 32MiB is in 128KiB big sectors. U-Boot occupies the 
>>> low 4 sectors,
>>> + * if we put environment next to it, we will have to occupy 128KiB 
>>> for it.
>>> + * Putting it at the top of flash we use only 32KiB. */
>>> +#define CFG_ENV_ADDR        (CFG_MONITOR_BASE + CFG_ENV_SECT_SIZE)
>>
>> This is a very ugly set up, because you split the U-Boot related
>> informatiomn, and you block both ends of your flash memory. Why don;t
>> you locate the environment for example in the third and fourts
>> sectors, i. e. use such a setup (called "embedded environment"):
>>
>>     sector 1:  32 KiB - U-Boot code
>>     sector 2:  32 KiB - more U-Boot code
>>     sector 3:  32 KiB - environment, first copy
>>     sector 4:  32 KiB - environment, second (redundant) copy
>>     sector 5: 128 KiB - more U-Boot code
>>     ...
>>
>> ?
> 
> Indeed. I think so too.
> I'll rework.
> 

In our board which has S29GL512N NOR flash, it has 512 128KiB big sector only.
So I leave this, and I'll modify only these comment.

     sector 1: 128 KiB - U-Boot code
     sector 2: 128 KiB - environment, first copy
     sector 3: 128 KiB - environment, second (redundant) copy
     sector 4: 128 KiB - more U-Boot code


Regards,
Atsuo Igarashi