How to reserve a RAM area to store some warm-reset-proof data?
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I have a board with ppc405, 128M RAM populated and booting with u-boot + linux 2.6.10 kernel. For some reason, I need to make sure some data can survive after warm-reset. As far as I know, u-boot have a parameter "pram=" for this, so-called "protected ram". But I don't know what to do next, shall I write a driver so that the application can access that RAM area?