On Tuesday, January 12, 2016 11:41:32 AM Rob Austein wrote: > If I understand correctly, the current schematics have both hard-wired > flash for the ARM CPU and also space for an SD card, with the ARM set > up to boot (only) from the hard-wired flash. > > a) Is this correct? > > b) If so, why do we have the SD card, and is its intended purpose > serious enough to merit including yet another driver? > > Keep in mind that removing the SD card presumably involves breaking > the tamper envelope, thus wiping the key store. > > c) Why are we using hard-wired flash at all, instead of, eg, just > booting from an SD card? Fear of SD card complexity (if so, see > (b)...)? > > d) If I understand correctly (questionable), SD cards take care of > wear leveling. I'm guessing that the hardwired flash envisioned > for the Alpha board does not, ie, that our driver for the > hard-wired flash may need to deal with wear-leveling itself. > > I don't really know how many write cycles we expect the hard-wired > flash to have, so I'm not sure how serious an issue this is. > > Apologies if some of this is a bit vague, software guy trying to > understand reasoning behind hardware choices.
Bump. I agree with Rob - the SD card does not appear that useful since we left the ARM A9 track. I propose we remove it from the Alpha, unless someone has a good use case in mind (Jakob explicitly CC:d). /Fredrik
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