Hardware, BIOS and OS
 

I have always wondered about the relationship between the hardware, BIOS/CMOS and OS.

I am re-reading the wikipedia article on UNIX and its development and they refer to UNIX being ported whenever is went to a new machine.

They don't really elaborate on what porting is in this context. From the article it would seem there was no BIOS in the early days and essentially no buffer between the UNIX operating system and the hardware. Correct me if I am wrong but wouldn't that mean that UNIX has 100% control of the hardware it is installed on? Z/Z

Any OS has 100% control of the hardware it's installed on, that's the function of the OS in the first place. So I'm not quite sure what you're getting at.

I think you might be overestimating the functionality of BIOS.

BIOS stands for Basic Input/Output System. Usually the firmware that controls input/output for the OS such as booting, keyboard, mouse and monitor.

CMOS stands for Complementary Metal Oxide Silicon. This is a flash-able or rewritable memory residing in the motherboard that keeps the record of the firmware; it is sustained mainly by a mini battery inside the pc.

OS = Operating System (such as Gnu/Linux distro, Mac X or Windows XP)

Basically, all in the hardware level, from the Processor chip to the north bridge (RAM) and to the south bridge (Graphic cards and ports), everything is marshaled by the firmware (BIOS); it is the role of the BIOS to prepare these devices to act in their respective functions before BIOS delivers it to the Operating System (OS) who acts as the customer-in-need to the hardware resources. The firmware (the mini system of the BIOS) resides in the CMOS.


It is not that there was no Bios in early days, there was always a way (a sort of bios) that the hardware devices were marshaled for use to the OS, no matter how simple they were before since there were no CDDVD no floppy no hard disk drives yet to mention and no usb ports to enumerate. Unix was earlier coded with the basic I/Os of the machine if it is intended (ported) into that machine, unlike today when firmwares have to be versatile to accommodate various operating systems installed at will by the owner. If by the word "buffer" you mean a coded layer that talks between the hardware and the OS, yes there was, and it varies between machine to machine.

By the way I am not knowledgeable enough to talk about these things that happened before I was born :) and I hope someone more knowledgeable about the ancient Unix ported machines shall come to the front and share his "experience" with you. I have no experience. Those were the days of the hippies; the days of Richard Matthew Stallman the father of GNU, the prophet of FSF, and the Pontificus Maximus of the Church of Emacs. {patience to my joke}

Hope this helps.

By 100% control of the hardware I mean UNIX allowed the user to control even the most rudimentary activities of the the hardware associated with it... stuff like power input and output from devices like the central processor or regulating the cycle speed at which disks are read or written or well just about anything we let our OS decide for us now... it is true that with win 7 for example you can underclock your processor to prevent overheating but whether the OS prevents overclocking or the BIOS is unknown to me. I do know that with some older amd motherboards you could choose to overclock the processor in the bios or cmos (not sure about which) and I am fairly certain overclocking was possible (but discouraged) in certain earlier versions of windows.

The issue is not overclocking specifically. I am moar interested in having greater understanding and control of my computers basic functions and of course if Linux can give me that control if I need it. Z/Z