Kernel Traffic #198 by Zack Brown

                        Kernel Traffic #198 For 30 Dec                         
                                                                               
                                 By Zack Brown                                 
                                                                               
Table Of Contents

  * Standard Format
  * Text Format
  * XML Source
  * Mailing List Stats For This Week
  * Threads Covered
   
    1. 10 Dec  - 22 Dec  (15 posts) Complaints About fbdev Design              
    2. 11 Dec  - 20 Dec  (4 posts)  Framebuffer Driver For Intel 810/815       
    3. 18 Dec  - 20 Dec  (9 posts)  Linux 2.4.21-pre2 Released                 
    4. 18 Dec  - 20 Dec  (2 posts)  chipsfb.c Updated To New 2.5 Framebuffer   
                                    API                                        
    5. 19 Dec  - 20 Dec  (3 posts)  Patch Submission Preferences               
    6. 26 Dec            (6 posts)  Kernel IRC Discussions                     
   
Mailing List Stats For This Week

We looked at 853 posts in 4246K.

There were 267 different contributors. 138 posted more than once. 136 posted
last week too.

The top posters of the week were:

  * 30 posts in 201K by "Martin J. Bligh"
  * 25 posts in 83K by John Bradford
  * 20 posts in 80K by Greg KH
  * 18 posts in 84K by Con Kolivas
  * 18 posts in 72K by Andrew Morton
  * Full Stats

 

1. Complaints About fbdev Design
Topics: Framebuffer
10 Dec  - 22 Dec  (15 posts) Archive Link: "atyfb in 2.5.51"

In the course of discussion, David S. Miller remarked, "I've always stated that
the whole fbdev model was flawed, it makes basic assumptions about how a video
card's memory and registers are accessed (ie. the programming model) and many
popular cards absolutely do not fit into that model." James Simmons replied, "I
agree that the design of the /dev/fbX interface is not the best. Unfortunely we
are stuck with it. Changing it would break userland apps." And David replied:

    I totally understand. I do not suggest to break fbdev in it's current form,
    too much stuff uses it.
   
    My main point was, don't be surprised the X servers, like the ATI driver,
    don't use fbdev and instead just mmap the device and simply program it
    directly.
   
    fbdev is nice, in the specific cases where the device fits the fbdev model,
    because once you have the kernel bits you have X support :)
   
Alan Cox also remarked here, "fbdev also can't be used in some situations on
x86. Deeply fascinating things happen on some x86 processors if you execute a
loop of code with an instruction that crosses two different memory types."

 

2. Framebuffer Driver For Intel 810/815
Topics: Framebuffer, Sound: i810
11 Dec  - 20 Dec  (4 posts) Archive Link: "[FBDEV]: Framebuffer driver for
Intel 810/815 chipsets"

Antonino Daplas said to James Simmons:

    It seems the fbdev framework is stable enough, and already in the
    development tree. So, I'm submitting a driver for the Intel 810/815 for
    review and perhaps inclusion to your tree (to get more testing), and
    hopefully merge with Linus's tree.
   
    The patch is against linux-2.5.51, but will not work yet because of 2
    reasons:
   
     1. agpgart is not working for the i810
     2. support for early agp initialization needs to be added.
   
    Once #1 is fixed, the driver should work as a module. And once #2 gets
    included, the driver can be compiled statically. Dave Jones (thanks for the
    help, by the way) has already #2 in his tree (tested and works), and is
    currently working on #1 (I have a hacked version at home).
   
    The driver should be compliant with fbdev-2.5, and should support most if
    not all features that are to be expected (modularity, state saving and
    restoring, full hardware support, etc). One thing also that's very
    important for many people is that the driver will work with XFree86 with
    its native i810 drivers without further modification, and quite stably too.
   
    The patch is at http://i810fb.sourceforge.net/linux-2.5.51-i810fb.diff.gz
   
James replied, "Applied !!!!"

 

3. Linux 2.4.21-pre2 Released
18 Dec  - 20 Dec  (9 posts) Archive Link: "Linux 2.4.21-pre2"

Marcelo Tosatti announced 2.4.21-pre2, and included the ChangeLog (http://
www.uwsg.indiana.edu/hypermail/linux/kernel/0212.2/0707.html) .

 

4. chipsfb.c Updated To New 2.5 Framebuffer API
Topics: Framebuffer, Ioctls
18 Dec  - 20 Dec  (2 posts) Archive Link: "[PATCH] update chipsfb.c to new API"

Paul Mackerras said:

    Here is a patch which updates chipsfb.c to the new 2.5 framebuffer API. It
    simplifies the driver quite a bit, partly because the new API is simpler
    and partly because the driver really can only handle one 65550 chip, since
    we access the chip via inb/outb to fixed I/O port numbers.
   
    I have tested it on a powerbook 3400, which has a C&T 65550 video chip with
    1MB of VRAM, and it seems to work just fine, at least in 8 bit mode. I
    guess I still need to add the pseudo_palette stuff for 16 bit mode.
    Unfortunately I can't test it under X at the moment because the X server I
    have installed on the 3400 is Xpmac, which doesn't work any more because
    the VC_GETMODE etc. ioctls have been removed. The 3400 is an old and slow
    machine with a small hard disk and an old Linux/PPC installation on it, and
    I don't really want to compile up XFree86 on it.
   
James Simmons replied, "Great!! Applied."

 

5. Patch Submission Preferences
19 Dec  - 20 Dec  (3 posts) Archive Link: "[PATCH] [v850] Reduce redundancy in
v850 linker scripts"

Miles Bader submitted a patch, and Linus Torvalds requested:

    Can you please make your patches be rooted the "standard" way, ie do
   
    diff -ruN linux-old-dir linux-new-dir
   
    so that they apply cleanly with a "patch -p1" and the diff headers say
    something like
   
            --- xxxx/arch/v850/vmlinux.lds.S
            +++ yyyy/arch/v850/vmlinux.lds.S
    
    because that's how all my tools are set up to take patches.
   
    I've done it by hand now, but it's somewhat tedious, and if I'm lazy (most
    of the time) it ends up meaning that I normally just drop patches that
    don't apply cleanly.
   
 

6. Kernel IRC Discussions
26 Dec  (6 posts) Archive Link: "Kernel Chat Room"

An anonymous person asked if there were any kernel chat rooms available.
Marc-Christian Petersen pointed him to http://www.kernelnewbies.org/, but the
anonymous person said they didn't mean a newbie chat room. Tomas Szepe replied,
"You aren't serious, are you? Can you at least go have a look before you frown
upon those people in #kernelnewbies?" And Arnaldo Carvalho de Melo also told
the person, "that is just the name, go there..." And Rik van Riel also added:

    That's exactly the reason we have 'newbies' in the name: to keep the 1337
    f01kz out and have a place where we can talk without having 1337 f01kz
    laugh at you.
   
    People who are interested in learning about kernel hacking, you're always
    welcome at:
   
    irc.kernelnewbies.org / #kernelnewbies
   
 

 

 

 

 

 

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