On Mon, Jun 27, 2011 at 5:29 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Mon, Jun 27, 2011 at 02:49:58PM -0600, Grant Likely wrote: >> > +struct { >> > + char magic[4] = { 'R', 'P', 'R', 'C' }; >> > + u32 version; >> > + u32 header_len; >> > + char header[...] = { header_len bytes of unformatted, textual header }; >> > + struct section { >> > + u32 type; >> > + u64 da; >> > + u32 len; >> > + u8 content[...] = { len bytes of binary data }; >> > + } [ no limit on number of sections ]; >> > +} __packed; >> >> Other have commented on the image format, so I'll skip this bit other >> than saying that I agree it would be great to have a common format. > > (Don't have the original message to reply to...) > > Do we really want to end up with header being 5 bytes, header_len set > as 5, and having to load/store all this data using byte loads/stores ? > > If we don't want that, then I suggest we get rid of the packed attribute, > and require stuff to be naturally aligned. > > First issue is that struct section could be much better layed out: > > struct section { > u32 type; > u32 len; > u64 da; > u8 content[]; > }; > > and require sizeof(struct section) % sizeof(u64) == 0 - iow, to find > the next section, round len up to sizeof(u64). Ditto for the header. Hopefully this will all be moot since it has been proposed to use elf images directly. g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html