From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sangmoon Kim <dogoil@etinsys.com>
Date: Mon, 28 Jun 2004 19:44:46 +0900
Subject: [U-Boot-Users] What are IBAT and DBAT?
References: <20040628062500.214.qmail@web20703.mail.yahoo.com>
Message-ID: <00a501c45cfc$ee3262d0$212d4cdc@smkim>
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To: u-boot@lists.denx.de

Hi,

> 3. Can IBAT and DBAT be modified dynamically? For example, if I want to
> access 0x70000000 ~ 0x78000000 temporarily, which is not defined in
> configuration header file, can I change the configuration of one of IBAT
> and DBAT pair, e.g. ibat2 and dbat2?
>

In case of board/etin/debris board.
DBAT1/IBAT1 is used for cache before RAM is initialized.
After RAM is initialized and the data memory area is mapped to RAM,
DBAT1/IBAT1 is not needed.
So I use DBAT1 for a flash memory at 0x78000000 after it.
See board/etin/debris/flash.c.
You can find the following code in flash_init function.

msr = get_msr();
set_msr(msr & ~(MSR_IR | MSR_DR));
mtibat1l(0x70000000 | BATL_PP_10 | BATL_CACHEINHIBIT);
mtibat1u(0x70000000 | BATU_BL_256M | BATU_VS | BATU_VP);
mtdbat1l(0x70000000 | BATL_PP_10 | BATL_CACHEINHIBIT);
mtdbat1u(0x70000000 | BATU_BL_256M | BATU_VS | BATU_VP);
set_msr(msr);

You can also change IBAT1 with similar method.

Regards,
Sangmoon Kim