From mboxrd@z Thu Jan 1 00:00:00 1970 From: linus.ml.walleij@gmail.com (Linus Walleij) Date: Mon, 22 Mar 2010 22:09:00 +0100 Subject: PXA3xx internal SRAM In-Reply-To: <20100321124739.GG30801@buzzloop.caiaq.de> References: <20100321124739.GG30801@buzzloop.caiaq.de> Message-ID: <63386a3d1003221409j63413b5o7a0515836eaa8b86@mail.gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 2010/3/21 Daniel Mack : > I wonder what this could be used for. Is there any kind of cache that > would be worth putting there to speed up things for example? Some ARM systems have TCM (Tightly Coupled Memory) which are similar in character but actually a feature of the ARM platforms rather than a custom memory for a certain SoC. You can find some documentation on how this can be used in Documentation/arm/tcm.txt, as you can see we can compile code there and the memory left after that can be used as a generic memory pool for fast always-on memory. I raised the question as to whether the IRQ vectors could be put into this memory but Russell says this is unfortunately not possible, because the top of the vector page is also used for other things. I don't know if this entire page can be moved to fast memory though, perhaps that concept need to be revisited? Linus Walleij