Jared Hulbert wrote: > On Fri, Aug 22, 2008 at 11:13 AM, Jamie Lokier <jamie@xxxxxxxxxxxxx> wrote: > > Greg Ungerer wrote: > >> One thing for sure is that many people who do non-MMU setups > >> are interested in XIP to get the space savings. These are very > >> often small devices with very constrained RAM and flash. (For > >> whatever it is worth single NOR flash only boards are common in > >> these smaller form factors :-) > > > > I'm using XIP on a device with 32MB RAM. The reason I use it is > > _partly_ to save RAM, partly because programs start about 10 times > > faster (reading NOR flash is slow and I keep the XIP region in RAM) > > What kind of NOR you using? That is not what I measure with fast > synchronous burst NOR's. I think the "fast" in "fast synchronous" gives it away :-) I'm using Spansion MirrorBit S29GL128N, which reads at about 0.6 MByte/s. Not because they're good, but because that's what the board I'm coding for has on it. I presume they were cheap and familiar to the board designers. (There is 32MB of RAM to play with after all.) So start a sequence of Busybox processes from a shell script is noticable, if it reads from NOR each time. Oh, and it's a 166MHz ARM, so it's quite capable of decompressing faster than the NOR can deliver. -- Jamie -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
