x86 setup code rewrite in C

x86 setup code rewrite in C

[H. Peter Anvin]

This patch set replaces the x86 setup code, which is currently all in
assembly, with a version written in C, using the ".code16gcc" feature
of binutils (which has been present since at least 2001.)

The new code is vastly easier to read, and, I hope, debug.  It should
be noted that I found a fair number of minor bugs while going through
this code, and have attempted to correct them.

In the process of doing so, it introduces several cleanups, in
particular:

- Obsoletes the hd_info field in the boot_params structure; they are
  only ever used for ST-506 (pre-IDE) drives and are pretty much
  guaranteed to be wrong on current BIOSes;
- Unifies the CPU feature bits between i386 and x86-64.  In the
  future, it should be possible to use arch/i386/boot/cpucheck.c to do
  the post-invocation CPU check currently done in
  arch/x86_64/kernel/trampoline.S, although this patch set doesn't
  introduce that change.
- boot_params is now a proper structure.

This code has been tested in -mm since early in the 2.6.22 cycle.

 arch/i386/boot/bootsect.S                     |   98 -
 arch/i386/boot/edd.S                          |  231 --
 arch/i386/boot/setup.S                        | 1075 -------------
 arch/i386/boot/video.S                        | 2043 --------------------------
 arch/i386/kernel/verify_cpu.S                 |   94 -
 arch/x86_64/boot/bootsect.S                   |   98 -
 arch/x86_64/boot/install.sh                   |    2
 arch/x86_64/boot/mtools.conf.in               |   17
 arch/x86_64/boot/setup.S                      |  826 ----------
 arch/x86_64/boot/tools/build.c                |  185 --
 b/Documentation/i386/zero-page.txt            |    1
 b/MAINTAINERS                                 |    4
 b/arch/i386/Kconfig.cpu                       |    6
 b/arch/i386/boot/Makefile                     |   46
 b/arch/i386/boot/a20.c                        |  161 ++
 b/arch/i386/boot/apm.c                        |   97 +
 b/arch/i386/boot/bitops.h                     |   45
 b/arch/i386/boot/boot.h                       |  290 +++
 b/arch/i386/boot/cmdline.c                    |   97 +
 b/arch/i386/boot/code16gcc.h                  |    9
 b/arch/i386/boot/compressed/Makefile          |    7
 b/arch/i386/boot/compressed/head.S            |    6
 b/arch/i386/boot/copy.S                       |  101 +
 b/arch/i386/boot/cpu.c                        |   69
 b/arch/i386/boot/cpucheck.c                   |  267 +++
 b/arch/i386/boot/edd.c                        |  196 ++
 b/arch/i386/boot/header.S                     |  283 +++
 b/arch/i386/boot/main.c                       |  161 ++
 b/arch/i386/boot/mca.c                        |   43
 b/arch/i386/boot/memory.c                     |   99 +
 b/arch/i386/boot/pm.c                         |  170 ++
 b/arch/i386/boot/pmjump.S                     |   54
 b/arch/i386/boot/printf.c                     |  331 ++++
 b/arch/i386/boot/setup.ld                     |   54
 b/arch/i386/boot/string.c                     |   34
 b/arch/i386/boot/tools/build.c                |  160 --
 b/arch/i386/boot/tty.c                        |  112 +
 b/arch/i386/boot/version.c                    |   23
 b/arch/i386/boot/vesa.h                       |   79 +
 b/arch/i386/boot/video-bios.c                 |  125 +
 b/arch/i386/boot/video-vesa.c                 |  284 +++
 b/arch/i386/boot/video-vga.c                  |  260 +++
 b/arch/i386/boot/video.c                      |  456 +++++
 b/arch/i386/boot/video.h                      |  145 +
 b/arch/i386/boot/voyager.c                    |   46
 b/arch/i386/kernel/cpu/Makefile               |    2
 b/arch/i386/kernel/cpu/addon_cpuid_features.c |   50
 b/arch/i386/kernel/cpu/common.c               |    2
 b/arch/i386/kernel/cpu/proc.c                 |   21
 b/arch/i386/kernel/e820.c                     |    2
 b/arch/i386/kernel/setup.c                    |   12
 b/arch/x86_64/Kconfig                         |    4
 b/arch/x86_64/boot/Makefile                   |  136 -
 b/arch/x86_64/boot/compressed/Makefile        |    9
 b/arch/x86_64/boot/compressed/head.S          |    6
 b/arch/x86_64/kernel/Makefile                 |    2
 b/arch/x86_64/kernel/setup.c                  |   21
 b/arch/x86_64/kernel/verify_cpu.S             |   22
 b/drivers/ide/legacy/hd.c                     |   73
 b/include/asm-i386/boot.h                     |    6
 b/include/asm-i386/bootparam.h                |   85 +
 b/include/asm-i386/cpufeature.h               |   26
 b/include/asm-i386/e820.h                     |   14
 b/include/asm-i386/processor.h                |    1
 b/include/asm-i386/required-features.h        |   39
 b/include/asm-i386/setup.h                    |   10
 b/include/asm-x86_64/alternative.h            |   68
 b/include/asm-x86_64/boot.h                   |   16
 b/include/asm-x86_64/bootparam.h              |    1
 b/include/asm-x86_64/cpufeature.h             |  115 -
 b/include/asm-x86_64/e820.h                   |    6
 b/include/asm-x86_64/processor.h              |    3
 b/include/asm-x86_64/required-features.h      |   46
 b/include/asm-x86_64/segment.h                |    8
 b/include/linux/edd.h                         |    4
 b/include/linux/screen_info.h                 |    9
 76 files changed, 4601 insertions(+), 5208 deletions(-)

Re: x86 setup code rewrite in C

[Yinghai Lu]

On 7/9/07, H. Peter Anvin <hpa@zytor.com> wrote:
> This patch set replaces the x86 setup code, which is currently all in
> assembly, with a version written in C, using the ".code16gcc" feature
> of binutils (which has been present since at least 2001.)
>
> The new code is vastly easier to read, and, I hope, debug.  It should
> be noted that I found a fair number of minor bugs while going through
> this code, and have attempted to correct them.
>
> In the process of doing so, it introduces several cleanups, in
> particular:
>
> - Obsoletes the hd_info field in the boot_params structure; they are
>   only ever used for ST-506 (pre-IDE) drives and are pretty much
>   guaranteed to be wrong on current BIOSes;
> - Unifies the CPU feature bits between i386 and x86-64.  In the
>   future, it should be possible to use arch/i386/boot/cpucheck.c to do
>   the post-invocation CPU check currently done in
>   arch/x86_64/kernel/trampoline.S, although this patch set doesn't
>   introduce that change.
> - boot_params is now a proper structure.
>
> This code has been tested in -mm since early in the 2.6.22 cycle.
>
>  arch/i386/boot/bootsect.S                     |   98 -
>  arch/i386/boot/edd.S                          |  231 --
>  arch/i386/boot/setup.S                        | 1075 -------------
>  arch/i386/boot/video.S                        | 2043 --------------------------
>  arch/i386/kernel/verify_cpu.S                 |   94 -
>  arch/x86_64/boot/bootsect.S                   |   98 -
>  arch/x86_64/boot/install.sh                   |    2
>  arch/x86_64/boot/mtools.conf.in               |   17
>  arch/x86_64/boot/setup.S                      |  826 ----------
>  arch/x86_64/boot/tools/build.c                |  185 --
>  b/Documentation/i386/zero-page.txt            |    1
>  b/MAINTAINERS                                 |    4
>  b/arch/i386/Kconfig.cpu                       |    6
>  b/arch/i386/boot/Makefile                     |   46
>  b/arch/i386/boot/a20.c                        |  161 ++
>  b/arch/i386/boot/apm.c                        |   97 +
>  b/arch/i386/boot/bitops.h                     |   45
>  b/arch/i386/boot/boot.h                       |  290 +++
>  b/arch/i386/boot/cmdline.c                    |   97 +
>  b/arch/i386/boot/code16gcc.h                  |    9
>  b/arch/i386/boot/compressed/Makefile          |    7
>  b/arch/i386/boot/compressed/head.S            |    6
>  b/arch/i386/boot/copy.S                       |  101 +
>  b/arch/i386/boot/cpu.c                        |   69
>  b/arch/i386/boot/cpucheck.c                   |  267 +++
>  b/arch/i386/boot/edd.c                        |  196 ++
>  b/arch/i386/boot/header.S                     |  283 +++
>  b/arch/i386/boot/main.c                       |  161 ++
>  b/arch/i386/boot/mca.c                        |   43
>  b/arch/i386/boot/memory.c                     |   99 +
>  b/arch/i386/boot/pm.c                         |  170 ++
>  b/arch/i386/boot/pmjump.S                     |   54
>  b/arch/i386/boot/printf.c                     |  331 ++++
>  b/arch/i386/boot/setup.ld                     |   54
>  b/arch/i386/boot/string.c                     |   34
>  b/arch/i386/boot/tools/build.c                |  160 --
>  b/arch/i386/boot/tty.c                        |  112 +
>  b/arch/i386/boot/version.c                    |   23
>  b/arch/i386/boot/vesa.h                       |   79 +
>  b/arch/i386/boot/video-bios.c                 |  125 +
>  b/arch/i386/boot/video-vesa.c                 |  284 +++
>  b/arch/i386/boot/video-vga.c                  |  260 +++
>  b/arch/i386/boot/video.c                      |  456 +++++
>  b/arch/i386/boot/video.h                      |  145 +
>  b/arch/i386/boot/voyager.c                    |   46
>  b/arch/i386/kernel/cpu/Makefile               |    2
>  b/arch/i386/kernel/cpu/addon_cpuid_features.c |   50
>  b/arch/i386/kernel/cpu/common.c               |    2
>  b/arch/i386/kernel/cpu/proc.c                 |   21
>  b/arch/i386/kernel/e820.c                     |    2
>  b/arch/i386/kernel/setup.c                    |   12
>  b/arch/x86_64/Kconfig                         |    4
>  b/arch/x86_64/boot/Makefile                   |  136 -
>  b/arch/x86_64/boot/compressed/Makefile        |    9
>  b/arch/x86_64/boot/compressed/head.S          |    6
>  b/arch/x86_64/kernel/Makefile                 |    2
>  b/arch/x86_64/kernel/setup.c                  |   21
>  b/arch/x86_64/kernel/verify_cpu.S             |   22
>  b/drivers/ide/legacy/hd.c                     |   73
>  b/include/asm-i386/boot.h                     |    6
>  b/include/asm-i386/bootparam.h                |   85 +
>  b/include/asm-i386/cpufeature.h               |   26
>  b/include/asm-i386/e820.h                     |   14
>  b/include/asm-i386/processor.h                |    1
>  b/include/asm-i386/required-features.h        |   39
>  b/include/asm-i386/setup.h                    |   10
>  b/include/asm-x86_64/alternative.h            |   68
>  b/include/asm-x86_64/boot.h                   |   16
>  b/include/asm-x86_64/bootparam.h              |    1
>  b/include/asm-x86_64/cpufeature.h             |  115 -
>  b/include/asm-x86_64/e820.h                   |    6
>  b/include/asm-x86_64/processor.h              |    3
>  b/include/asm-x86_64/required-features.h      |   46
>  b/include/asm-x86_64/segment.h                |    8
>  b/include/linux/edd.h                         |    4
>  b/include/linux/screen_info.h                 |    9
>  76 files changed, 4601 insertions(+), 5208 deletions(-)

is possible to put 16bit c in seperate directory. or rename them with _16.c?

YH

Re: x86 setup code rewrite in C

[H. Peter Anvin]

Yinghai Lu wrote:
> 
> is possible to put 16bit c in seperate directory. or rename them with 
> _16.c?
> 

They *ARE* in a separate directory, specifically arch/i386/boot.  All
the *.c files in there are 16 bits; the 32-bit code is in
arch/i386/boot/compressed or arch/i386/kernel.

	-hpa

Re: x86 setup code rewrite in C

[Jeff Garzik]

H. Peter Anvin wrote:
> This patch set replaces the x86 setup code, which is currently all in
> assembly, with a version written in C, using the ".code16gcc" feature
> of binutils (which has been present since at least 2001.)
> 
> The new code is vastly easier to read, and, I hope, debug.  It should
> be noted that I found a fair number of minor bugs while going through
> this code, and have attempted to correct them.
> 
> In the process of doing so, it introduces several cleanups, in
> particular:
> 
> - Obsoletes the hd_info field in the boot_params structure; they are
>   only ever used for ST-506 (pre-IDE) drives and are pretty much
>   guaranteed to be wrong on current BIOSes;
> - Unifies the CPU feature bits between i386 and x86-64.  In the
>   future, it should be possible to use arch/i386/boot/cpucheck.c to do
>   the post-invocation CPU check currently done in
>   arch/x86_64/kernel/trampoline.S, although this patch set doesn't
>   introduce that change.
> - boot_params is now a proper structure.
> 
> This code has been tested in -mm since early in the 2.6.22 cycle.

ACK

I don't claim to be an expert in this area, but I definitely support 
this going in, and I really did read every patch.  :)

The only minor problem I found was a misspelling "paragrap" (perhaps 
plural) in one of the patches.

	Jeff

Re: x86 setup code rewrite in C

[Jeremy Fitzhardinge]

H. Peter Anvin wrote:
> This patch set replaces the x86 setup code, which is currently all in
> assembly, with a version written in C, using the ".code16gcc" feature
> of binutils (which has been present since at least 2001.)
>
> The new code is vastly easier to read, and, I hope, debug.  It should
> be noted that I found a fair number of minor bugs while going through
> this code, and have attempted to correct them.
>
> In the process of doing so, it introduces several cleanups, in
> particular:
>
> - Obsoletes the hd_info field in the boot_params structure; they are
>   only ever used for ST-506 (pre-IDE) drives and are pretty much
>   guaranteed to be wrong on current BIOSes;
> - Unifies the CPU feature bits between i386 and x86-64.  In the
>   future, it should be possible to use arch/i386/boot/cpucheck.c to do
>   the post-invocation CPU check currently done in
>   arch/x86_64/kernel/trampoline.S, although this patch set doesn't
>   introduce that change.
> - boot_params is now a proper structure.
>
> This code has been tested in -mm since early in the 2.6.22 cycle.
>   

This stuff is good.  I haven't read through this series in detail, but I 
have been working on the code in -mm and its a clear improvement.

Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>

    J

Re: x86 setup code rewrite in C

[Al Boldi]

H. Peter Anvin wrote:
> This patch set replaces the x86 setup code, which is currently all in
> assembly, with a version written in C, using the ".code16gcc" feature
> of binutils (which has been present since at least 2001.)
>
> The new code is vastly easier to read, and, I hope, debug.  It should
> be noted that I found a fair number of minor bugs while going through
> this code, and have attempted to correct them.

I have an i810 which supends-to-ram just fine, but when booted over pxe it 
just hangs.  Will these patches fix this, and if so, is there an easy 
tar-ball against 2.6.22?


Thanks!

--
Al

Re: x86 setup code rewrite in C

[H. Peter Anvin]

Al Boldi wrote:
> H. Peter Anvin wrote:
>> This patch set replaces the x86 setup code, which is currently all in
>> assembly, with a version written in C, using the ".code16gcc" feature
>> of binutils (which has been present since at least 2001.)
>>
>> The new code is vastly easier to read, and, I hope, debug.  It should
>> be noted that I found a fair number of minor bugs while going through
>> this code, and have attempted to correct them.
> 
> I have an i810 which supends-to-ram just fine, but when booted over pxe it 
> just hangs.  Will these patches fix this, and if so, is there an easy 
> tar-ball against 2.6.22?

There is absolutely no way to know, other than testing it.  There isn't
any real reason to suspect the setup code in your case, but it's worth a
shot, I guess.

There is a git tree on git.kernel.org you can pull, which is current
against 2.6.22.

	-hpa

Re: x86 setup code rewrite in C

[Al Boldi]

H. Peter Anvin wrote:
> Al Boldi wrote:
> > H. Peter Anvin wrote:
> >> This patch set replaces the x86 setup code, which is currently all in
> >> assembly, with a version written in C, using the ".code16gcc" feature
> >> of binutils (which has been present since at least 2001.)
> >>
> >> The new code is vastly easier to read, and, I hope, debug.  It should
> >> be noted that I found a fair number of minor bugs while going through
> >> this code, and have attempted to correct them.
> >
> > I have an i810 which supends-to-ram just fine, but when booted over pxe
> > it just hangs.  Will these patches fix this, and if so, is there an easy
> > tar-ball against 2.6.22?
>
> There is absolutely no way to know, other than testing it.  There isn't
> any real reason to suspect the setup code in your case, but it's worth a
> shot, I guess.

Well it's a bit far fetched to suspect the setup code, but I have another 
i440 that suspends-to-ram when booted over pxe without any problems.  And, 
booting the i810 through dos-lilo also hangs STR, so that's why assumed it 
may be a setup code thing.

> There is a git tree on git.kernel.org you can pull, which is current
> against 2.6.22.

How can I pull a tar-ball from that without using a git client?


Thanks!

--
Al

Re: x86 setup code rewrite in C

[H. Peter Anvin]

Al Boldi wrote:
> 
>> There is a git tree on git.kernel.org you can pull, which is current
>> against 2.6.22.
> 
> How can I pull a tar-ball from that without using a git client?
> 

I don't think you can.

	-hpa

Re: x86 setup code rewrite in C

[Randy Dunlap]

On Tue, 10 Jul 2007 14:13:50 -0700 H. Peter Anvin wrote:

> Al Boldi wrote:
> > 
> >> There is a git tree on git.kernel.org you can pull, which is current
> >> against 2.6.22.
> > 
> > How can I pull a tar-ball from that without using a git client?
> > 
> 
> I don't think you can.

Too bad, not just for x86-newsetup but lots of other gits as well.

---
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***

Re: x86 setup code rewrite in C

[Adrian Bunk]

On Tue, Jul 10, 2007 at 02:13:50PM -0700, H. Peter Anvin wrote:
> Al Boldi wrote:
> > 
> >> There is a git tree on git.kernel.org you can pull, which is current
> >> against 2.6.22.
> > 
> > How can I pull a tar-ball from that without using a git client?
> > 
> 
> I don't think you can.

gitweb has a snapshot feature that should offer this, but git.kernel.org 
seems to only give garbage when you click on it.

> 	-hpa

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

Re: x86 setup code rewrite in C

[H. Peter Anvin]

Randy Dunlap wrote:
> 
> Too bad, not just for x86-newsetup but lots of other gits as well.
> 

Well, it's a function of gitweb, but we have been forced to disable it
because it interferes hideously with the caching system.  We'll
hopefully eventually get around to fixing it, but it's not a high
priority unfortunately.

So far our effort at getting paid staff seems to have fallen through :(

	-hpa

Re: x86 setup code rewrite in C

[Chris Smith]

On 7/10/07, H. Peter Anvin <hpa@zytor.com> wrote:
> So far our effort at getting paid staff seems to have fallen through :(
>
>        -hpa

Presumably the 501c status hasn't changed since OLS?
If a paid position isn't forthcoming, perhaps there can be a bounty
system for people to contribute $ towards desired functionality.
-- 
Christopher Smith

Re: x86 setup code rewrite in C

[H. Peter Anvin]

Chris Smith wrote:
> On 7/10/07, H. Peter Anvin <hpa@zytor.com> wrote:
>> So far our effort at getting paid staff seems to have fallen through :(
>>
>>        -hpa
> 
> Presumably the 501c status hasn't changed since OLS?
> If a paid position isn't forthcoming, perhaps there can be a bounty
> system for people to contribute $ towards desired functionality.

501(c)3 is still pending, unfortunately.

We actually get a lot of offer for volunteers, but we can't use them
because we lack the kind of management structure needed to run them.  As
a result, we can only take on people willing to spend a sizable chunk of
time doing kernel.org stuff, *and* are already known by the rest of the
admin team to be self-starters.

However, even that is really difficult enough.  kernel.org definitely
takes a lot more of my time than I would like.

	-hpa