Intel P6 / AMD K7 MTRRs management IOCtl PDD ver.0.05a

0. Table of Contents

0. Table of Contents
1. Welcome
- 1.1. Copyright and Disclaimer
- 1.2. System Requirements
- 1.3. Contact Author
- 1.4. Revision History
2. How to use
- 2.1. Driver Installation
- 2.2. How to apply write-combining to video frame buffer aperture
3. P6K7MTRR.sys device IOCtl reference
- 3.1. Constants and Structures
- 3.2. Precautions and Limitations
- 3.3. DosDevIOCtl() interface
  - 3.3.1. P6K7MTRR_SETMTRR2DEFAULT (40h)
  - 3.3.2. P6K7MTRR_SETMTRRDEFTYPE (41h)
  - 3.3.3. P6K7MTRR_SETMTRRFIXEDRANGE (42h)
  - 3.3.4. P6K7MTRR_SETMTRRVARIABLERANGE (43h)
  - 3.3.5. P6K7MTRR_QRYMTRRCAP (60h)
  - 3.3.6. P6K7MTRR_QRYMTRRDEFTYPE (61h)
  - 3.3.7. P6K7MTRR_QRYMTRRFIXEDRANGE (62h)
  - 3.3.8. P6K7MTRR_QRYMTRRVARIABLERANGE (63h)
4. Troubleshooting
5. Credits

1. Welcome

P6K7MTRR.sys is a simple interface physical device driver(PDD) that can manage Memory Type Range Registers(MTRRs) of Intel P6^* / AMD K7^** series processors. Programmer can query/modify any MTRR settings via DosDevIOCtl() API, from non-Ring0 privileges.
A sample executable, VFBWC.exe, using P6K7MTRR.sys, sets MTRR write-combining strategy to video frame buffer aperture. It can often improve graphic performance, especially DIVE.

^* P6 includes PentiumPro, PentiumII, Celeron and PentiumIII.
^** K7 includes Athlon and Duron.

1.1. Copyright and Disclaimer

'THIS SOFTWARE (P6K7MTRR.SYS AND ITS SOURCES) AND WHOLE SET OF DOCUMENTS' (CALLED 'THE PRODUCT') ARE ENTIRELY COPYRIGHTED BY TAKAYUKI 'JANUARY JUNE' SUWA/BELIEFIA PRODUCTIONS, AUTHOR/HOLDER OF THE PRODUCT.
THE PRODUCT IS STILL UNDER DEVELOPMENT AT THE DISTRIBUTION AND MAY BE OCCURED ANY MODIFICATION/DELETION OF APPEARANCE/FUNCTION OR TERMINATION OF DEVELOPMENT/SERVICE IN FUTURE WITHOUT NOTICE.
THE PRODUCT IS PROVIDED 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY DAMAGES, WHETHER IN CONTRACT OR TORT (INCLUDED NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THE PRODUCT, EVEN THOUGH SUCH HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF ANY DAMAGE.

We are regarded you agree disclaimer above at first installation of P6K7MTRR.SYS. If you disagree above, you must discard all files of the product.

1.2. System Requirements

This software will be functioned in environment such as:

OS/2 version 3 (or later)
Intel P6 / AMD K7 series processor
Some P6/K7 MTRRs knowledge, with development

1.3. Contact Author

Email to Takayuki 'January June' Suwa:

mailto:jjsuwa@sys3175.com

1.4. Revision History

ver.0.01 - December 1st,1999
1. Initial release.
ver.0.02 - December 4th,1999
1. (P6MTRR.sys) Added parameter/data checking.
2. (P6MTRR.h) Added some comments/constants.
3. (P6MTRR.sym) Included for kernel debugger.
ver.0.03 - January 3rd,2000
1. (P6MTRR.sys) Added P6 fast string feature management IOCtl, P6MTRR_QRYFASTSTRING / P6MTRR_QRYFASTSTRING.
2. (P6MTRR.h) Added P6MTRR_QRYFASTSTRING / P6MTRR_QRYFASTSTRING constants/structure definition.
3. (P6MTRR.asm/P6MTRR.def) Included source. To build, use ALP and LINK386.
ver.0.04 - January 17th,2000
1. (P6K7MTRR.sys) Renamed to P6K7MTRR.sys due to support AMD K7(Athlon). Obsoleted P6 fast string feature management.
2. (P6K7MTRR.h) Renamed filename and symbols. Removed P6MTRR_QRYFASTSTRING / P6MTRR_QRYFASTSTRING constants/structure definition.
3. (P6K7MTRR.asm/P6K7MTRR.def) Renamed.
4. (VFBWC.exe) Rewrote wholly.
5. (READMEJ) Added Japanese documentation.
ver.0.04 r2 - January 19th,2000
1. (VFBWC.exe) Improved video frame buffer size detection. Added -1 option for frational video frame buffer size.
ver.0.05 - October 9th,2000
1. (P6K7MTRR.sys) Added resetting to default feature, P6K7MTRR_SETMTRR2DEFAULT.
2. (P6K7MTRR.h) Added P6K7MTRR_SETMTRR2DEFAULT constant definition.
3. (VFBWC.exe) Changed to reset to default using P6K7MTRR_SETMTRR2DEFAULT before applying settings.
4. (README.htm) Renamed/converted from README and enriched contents.
ver.0.05a - October 30th,2000
1. (P6K7MTRR.sys) Reduced resident size slightly.
2. (VFBWC.exe) Added more strict PM activity checking.

2. How to use

2.1. Driver Installation

Unzip archive to where you desire. (e.g. C:\P6K7MTRR)
Add
DEVICE=d:\path\P6K7MTRR.sys
line to your CONFIG.SYS. (d and path must be replaced with actual installation drive/path)

Restart your system. If installation successfully, you will see:

P6K7MTRR.sys  Intel P6 / AMD K7 MTRRs management IOCtl PDD  ver.0.05a
Copyright 1999-2000 January June / ûΘë╛òP(Yotogi-Hime) / Beliefia Productions.
Intel P6 MTRR feature is found. The driver has been installed.

P6K7MTRR.sys  Intel P6 / AMD K7 MTRRs management IOCtl PDD  ver.0.05a
Copyright 1999-2000 January June / ûΘë╛òP(Yotogi-Hime) / Beliefia Productions.
AMD K7 MTRR feature is found. The driver has been installed.

2.2. How to apply write-combining to video frame buffer aperture

Run VFBWC.exe from PM-aware environment. You will see such as:

VFBWC.exe  Video Frame Buffer to Write-Combining for P6K7MTRR.sys  ver.0.04
Copyright 1999-2000 January June / ûΘë╛òP(Yotogi-Hime) / Beliefia Productions.
 
video frame buffer aperture PhysAddr : 0x48000000
video frame buffer aperture Size     : 0x00200000
setting validity                     : valid
A0000-BFFFF fixed range (VGA region) : as-is
 
To apply this setting, rerun VFBWC.exe with -a option.

In this example, video frame buffer aperture PhysAddr/Size detected is 0x48000000/0x00200000.

If detection seems true, rerun VFBWC.exe with -a option.
If seems false, add correct PhysAddr and Size in hexadecimal such as:
VFBWC 0x48000000 0x200000 -a
You will see:
Setting has been applied.
To apply automatically in startup sequence, add
CALL=d:\path\VFBWC.exe PhysAddr Size -a
line to your CONFIG.SYS. (d and path must be replaced with actual installation drive/path)
PhysAddr and Size also must be specified, because autodetection cannot be used in pre-PM environment.
And for laptop/notebook machines,
RUN=d:\path\VFBWC.exe PhysAddr Size -a -d
to reapply automatically after APM suspend resuming.

Run VFBWC.exe with -?, and you will see usage summary and other options:

usage:
  VFBWC.exe  [-options]  [{PhysAddr}  {Size} (in hex.)]
    PhysAddr/Size is not specified, VFBWC.exe will try to detect physical
    address/size of video frame buffer aperture.
    (requires Presentation Manager activity and DIVE feature)
options:
  -1  rounds Size up to 1MB unit
  -a  applies setting to MTTRs actually with specified/detected range
  -b  rings beep when apply setting
  -d  goes into daemon mode, re-apply automatically after APM suspend resuming
  -i  turns to invalid for variable MTRRs / UC for fixed A0000-BFFFF MTRR
        rather than valid/WC
  -v  with -a, also applies WC to fixed A0000-BFFFF MTRR (VGA region)
  -?  displays this message

3. P6K7MTRR.sys device IOCtl reference

3.1. Constants and Structures

All constants and structures needed for development are defined in P6K7MTRR.h. See also.

3.2. Precautions and Limitations

Be with great care when modifying any MTRRs.
Improper MTRR settings may cause kernel-level crashes or significant poor performance immediately.
One DosDevIOCtl() call will affect one of any CPUs only.
Thus, in SMP environments, multiple DosDevIOCtl() calls must be required with thread-CPU binding such as DosSetThreadAffinity() (Warp4.5 only).
(Hmmm, OS/2 Warp Server SMP seems to lack such APIs...)

3.3. DosDevIOCtl() interface

3.3.1. P6K7MTRR_SETMTRR2DEFAULT (40h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_SETMTRR2DEFAULT (40h)

Desctiption:

Set all MTRR settings to default

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

None. This pointer should be NULL.

Returns:

NO_ERROR: Success.
ERROR_INVALID_PARAMETER: Not supported.

Remarks:

In this function, 'default' is set of all MTRR settings at initialization of P6K7MTRR.sys in startup sequence.

3.3.2. P6K7MTRR_SETMTRRDEFTYPE (41h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_SETMTRRDEFTYPE (41h)

Desctiption:

Set MTRR default type

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

P6K7MTRRDEFTYPEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.
ERROR_INVALID_PARAMETER: Wrong default memory type is specified.

Remarks:

MTRR enabled flag cannot be 0, because of restriction of P6K7MTRR.sys.

3.3.3. P6K7MTRR_SETMTRRFIXEDRANGE (42h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_SETMTRRFIXEDRANGE (42h)

Desctiption:

Set MTRR fixed ranges

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

P6K7MTRRFIXEDRANGEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.
ERROR_INVALID_PARAMETER: Wrong memory types are specified.

Remarks:

None.

3.3.4. P6K7MTRR_SETMTRRVARIABLERANGE (43h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_SETMTRRVARIABLERANGE (43h)

Desctiption:

Set MTRR variable range

Parameter Packet Format:

P6K7MTRRVARIABLERANGEPARM. See also P6K7MTRR.h.

Data Packet Format:

P6K7MTRRVARIABLERANGEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.
ERROR_INVALID_PARAMETER: Either wrong index or memory type is specified (or both).

Remarks:

None.

3.3.5. P6K7MTRR_QRYMTRRCAP (60h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_QRYMTRRCAP (60h)

Desctiption:

Query MTRR capabilities

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

P6K7MTRRCAPDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.

Remarks:

None.

3.3.6. P6K7MTRR_QRYMTRRDEFTYPE (61h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_QRYMTRRDEFTYPE (61h)

Desctiption:

Query MTRR default type

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

P6K7MTRRDEFTYPEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.

Remarks:

None.

3.3.7. P6K7MTRR_QRYMTRRFIXEDRANGE (62h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_QRYMTRRFIXEDRANGE (62h)

Desctiption:

Query MTRR fixed ranges

Parameter Packet Format:

None. This pointer should be NULL.

Data Packet Format:

P6K7MTRRFIXEDRANGEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.

Remarks:

None.

3.3.8. P6K7MTRR_QRYMTRRVARIABLERANGE (63h)

Category:

IOCTL_P6K7MTRR (c4h)

Function:

P6K7MTRR_QRYMTRRVARIABLERANGE (63h)

Desctiption:

Set MTRR variable range

Parameter Packet Format:

P6K7MTRRVARIABLERANGEPARM. See also P6K7MTRR.h.

Data Packet Format:

P6K7MTRRVARIABLERANGEDATA. See also P6K7MTRR.h.

Returns:

NO_ERROR: Success.
ERROR_INVALID_PARAMETER: Wrong index is specified.

Remarks:

None.

4. Troubleshooting

A. P6K7MTRR.sys cannot be installed on my machine...
Q. CPU of your machine is not Intel P6 nor AMD K7 :)
A. VFBWC autodetection is not functioned...
Q. This feature requires PM activity and DIVE feature. Please check whether MMPM/2 is installed.

5. Credits

Development
Special thanks to

Copyright 1999-2000 January June / Yotogi-Hime / Beliefia Productions. All rights reserved.
Copyrighted works(images, musics, programs, and so on), trademarks and servicemarks in this document are owned by their respective owners.

[This document is HTML3.2(Wilbur)-compliant.]