From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from felloff.net ([199.191.58.38]) by ttr; Sat Aug 16 21:54:08 EDT 2014 Message-ID: List-ID: <9front.9front.org> X-Glyph: ➈ X-Bullshit: lossless DOM-oriented manager Date: Sun, 17 Aug 2014 03:54:01 +0200 From: cinap_lenrek@felloff.net To: 9front@9front.org Subject: Re: [9front] termrc and aux/realemu In-Reply-To: <6e9db28ce5e4bac6fac9fa0c0c463e7b@saturn.jitaku.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit every video mode is special. aux/vga does special stuff for every one of them like mapping mmio registers from named hardware segments or reading/writing special control files of the kernel half driver. vesa works with doing vesa bios calls. /dev/realmode was initially provided by the kernel, by doing a mode switch to realmode and executing the code. with realemu /dev/realmode is provided by userspace fileserver which binds over /dev and hides the kernel mode /dev/realmode files. these days, 9front has no kernel mode /dev/realmode anymore as realemu works good enougth and realmode isnt even available in 64 bit kernel. the modularity remains. this is good for debugging, as you can run realemu with tracing modes that let you see what io ports are read and written by the video bios code. also, mounting and unmounting lets us make snapshots of the bios memory areas to rerun tests from a defined state the video bios memory. (theres the vbt program and scripts to try to bruteforce hidden video modes that uses this). conflating aux/vga with realemu isnt right in my opinion. realemu can be used in many different ways and is not limited to running vesa bios code (see comload) and aux/vga has no need to depend on it directly. -- cinap