On 10/24/24 03:01, Mike Larkin wrote: > > Every one of us who has worked in this area, at this level, has read those > 800+ page documents. Sometimes they are many thousands of pages (eg the latest > Intel SDM or latest ACPI spec). > > Tell us what you are doing and what you want to know and maybe we can point > you to the right docs, but there is no short-cutting reading the reference > manuals. >
I would really like to understand why this architecture stood the test of time. Just because it boots in 8 bit CPU mode from the 70ties not even capable of beating a 6502? Just because developers were not continuously forced to throw away all knowledge and could build upon it? Seems to be the reason. Intel tried to throw away legacy burdens and got set straight by AMD. I am currently approaching page 4000 of documentation. Shaking heads. Unbelievable. What I am lacking so far is a current PCI bus specification. This seems to not be available to non members who I am certainly not. Coming from a hardware background, documents like this <https://www.intel.sg/content/dam/doc/datasheet/io-controller-hub-10-family-datasheet.pdf> clearly were a waste of time, at least when your goal is not to produce mainboards. Well. Normally you would program devices directly. It even contains write-once-by-firmware registers. It will take some time for me to understand the reasoning behind this. Not questioning there are no reasons for doing it that way. I am just trying to make me stop hating that architecture. I am still failing at this task but I would like to overcome this. At least it has linear address space. Oh. What a wonder. Every 68k had this decades ago. Oh sorry. Your comments are very helpful to me so far so thank you. Because the machine independent parts in the kernel really are abstractions of formerly machine dependent parts, understanding the worst case of those - namely x86 and amd64 - will help me understand those. I am still in the process of reading x86/amd64 documentation even if it make me shake my head every so often. Regards, -- Christian
