From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Rini Date: Fri, 5 Jul 2013 08:51:03 -0400 Subject: [U-Boot] [PATCH 2/2] am335x_evm: Update, document Falcon Mode support In-Reply-To: References: <1372882163-9299-1-git-send-email-trini@ti.com> <1372882163-9299-3-git-send-email-trini@ti.com> <87ip0rpc3f.fsf@dell.be.48ers.dk> <20130703223028.GE16630@bill-the-cat> Message-ID: <20130705125103.GI16630@bill-the-cat> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Thu, Jul 04, 2013 at 07:39:48AM +0000, Romain Izard wrote: > Tom> +A further word of warning about using eMMC and partition tables. When > Tom> +working with SD cards we can get away with erasing small areas at a time, > Tom> +however on eMMC we must keep erases aligned to eraseblocks and thus the > Tom> +first erase we issue will erase the partition table. > > Peter> Really? I thought eMMC behaved just like SD cards? > > Tom> Yes, really. We know what the erase block size is, and round our > Tom> commands, probably because we really have to. SD cards take care of > Tom> things for us, for better or worse. > > But why do we bother with erasing the eMMC in the first place? The erase > commands are wholly optional, and only make sense as a TRIM mechanism, > which is not our case as we will fill the memory as soon as it has been > erased. > > There is no problem in writing directly in the memory, even if it has > not been erased previously. Or is it a measure to detect interrupted > writes ? I hadn't thought of it like that, I had been thinking of it like NAND for some reason. I'll update the instructions (and write a bunch of garbage first) and re-confirm things. Thanks! -- Tom -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 836 bytes Desc: Digital signature URL: