Tarl Neustaedter wrote:
On 2013-Jul-23 10:42 , Lennart Sorensen wrote:
I don't think I believe the 8MB value however. They are certainly bigger than they used to be and often a chunk of it is compressed and only decompressed when you run the setup.
8MB is the size of some of the EFI proms (with all debug turned on). Most BIOS are under 1MB. Openboot is usually under 512kb, I presume OpenBios would be the same.
Somebody contracting for one of the BIOS vendors (I forget who) told me that not only did a mainboard manufacturer choose from a "kit of parts" when building a BIOS (i.e. a Flash image or whatever), but that various components were included/excluded dynamically when the system booted. I don't know whether that implies that (in the case of that vendor) the Flash image was effectively a filesystem or if blocks of code were just moved around and merged as required, but it's a fair bet that the size of the Flash device has very little relation to the amount of memory occupied by the BIOS when control is transferred to the OS or second-stage loader.
Tarl- I don't like to impose, but could I ask one question about Openboot's Forth, either here or by mail?