Archive for April, 2003

Yet another Unisys Presentation

Monday, April 28th, 2003

[ from the this-will-be-fun dept. ]

This week we are graced with another guest lecture from Unisys, a fantastic opportunity to once again ask about corporate sponsorship of Software Patents such as that used by the LZW compression algorithm. I enjoy these talks…

Jon.

Revolution OS

Monday, April 28th, 2003

[ from the RMS-really-does-rule dept. ]

Hi,

Revolution OS has arrived. We watched it over the weekend and there are plans to arrange a screening.

The Memory Managemend issues are still ongoing however I have now written the equilavent of an LED attached to the serial port and have some position independent hard coded assembly to flash the framebuffer so that I know where things are going stray. :-)

Jon.

Project Update

Sunday, April 27th, 2003

[ from the giant-pandas-are-everywhere dept. ]

Well the project code is a good few thousand lines now and can talk to the prom, framebuffer, etc. though the memory management code is starting to get really bothering – at the moment everything I try to do seems to be failing, and it is very difficult to determine where when you have no hardware debugger. I am writing a minimal pixel painting assembly routing for emergency display blanking to determine whether the code is still running at certain points or if it has gone for a nice little trip through the memory to execute whatever it finds there again…

The memory concept at the moment is to have a single global free list which is initialised to contain a double(y) linked list of structs describing pages of memory – effectively all memory is one giant array of page frames with mimimal cleaverness implemented at this stage.

Jon.

-mrelocatable-lib got2

Tuesday, April 22nd, 2003

[ from the got2-find-the-answer dept. ]

The problem that was happening with figuring out how to generate a got2 section for relocating data between kernel link address relocation has been resolved by using the gcc CFLAGS entry“-mrelocatable-lib”. Perhaps there is some documentation somewhere though it remains quite elusive.

Jon.

New Machines

Monday, April 21st, 2003

[ from the not-more-junk-jcm? dept. ]

I picked up another IPX and SPARCstation 20 this afternoon, bringing my total Sun count to 5 now. I saw a rather nice HP 9000 which is frankly too large even for me to think I am going to fit in my house or parents house. There was an SGI Indy which I think I may pick up soon for a reasonable price. [UPDATED: 17:40:15 by jcm] It was an Indigo and not an Indy.

Jon.

Applicant Feedback

Sunday, April 13th, 2003

[ from the laugh-it-is-funny dept. ]

Hi, I found this excellent “memo” from an “Applicant” who was turned down for a job and subsequently offered feedback.

Jon.

Open Firmware Crazy Shit

Sunday, April 13th, 2003

[ from the crunch-time dept. ]

Ok, so I started writing real actual code. Amazing. Anyway, I discovered that Open Firmware is more than a little fiddly to deal with. I understand most of the code I have encountered though I’m not sure why it is necessary to relocate the GOT (Global Offset Table) before init and move it back after. Little things like this I will hopefully figure out later on today.

Jon.