I've put it back in, changing it to "3" because it is the most
conservative choice. Below is the revised patch (also available at
http://jpj.net/~trevor/linux/m386-v7.diff). It incorporates a couple of
suggestions from Michael Chastain. Thanks are due to "ketil" who
suggested using just a number for the processor family, and to Mike
Jagdis, David Fries and Matthew Kirkwood for their comments and
suggestions.
___
Trevor Johnson
diff -ru linux-2.1.89.orig/Documentation/Configure.help linux/Documentation/Configure.help
--- linux-2.1.89.orig/Documentation/Configure.help Sat Mar 7 12:58:36 1998
+++ linux/Documentation/Configure.help Sun Mar 8 11:15:04 1998
@@ -1136,18 +1136,21 @@
Processor family
CONFIG_M386
- This is the processor type of your CPU. This information is used for
- optimizing purposes. In order to compile a kernel that can run on
- all x86 CPU types (albeit not optimally fast), you can specify
- "386" here. If you specify one of "486" or "Pentium" or "PPro",
- then the kernel will run on all of these CPUs: 486 and Pentium
- (=586) and Pentium Pro (=686). In rare cases, it can make sense to
- specify "Pentium" even if running on a 486: the kernel will be
- smaller but slower.
+ This information is used for optimization. Here are the settings
+ recommended for greatest speed:
+ - 3 for the AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX and Cyrix 486DLC/DLC2
+ - 4 for the AMD/Cyrix/IBM/Intel DX4 or 486DX/DX2/SL/SX/SX2, AMD/Cyrix
+ 5x86, Cyrix MediaGX, NexGen Nx586 and UMC U5D or U5S
+ - 5 for the AMD K5, K6 and K6-3D, Cyrix/IBM/National Semiconductor 6x86
+ and GXm, IDT Centaur WinChip C6, and Intel Pentium/Pentium MMX
+ - 6 for the Cyrix/IBM/National Semiconductor 6x86MX and Intel Pentium
+ II/Pentium Pro
+ A kernel will not necessarily run correctly on CPUs from a lower family
+ than the one for which it is compiled. Compiling for "3" will work on
+ all the CPUs mentioned, but at a penalty in performance on newer ones.
If you have a multiple processor machine and want Linux to use all
the processors in parallel, set the SMP variable in the toplevel
kernel Makefile.
- If you don't know what to do, say "386".
Video mode selection support
CONFIG_VIDEO_SELECT
diff -ru linux-2.1.89.orig/arch/i386/config.in linux/arch/i386/config.in
--- linux-2.1.89.orig/arch/i386/config.in Mon Feb 2 15:18:15 1998
+++ linux/arch/i386/config.in Sun Mar 8 11:03:57 1998
@@ -12,10 +12,10 @@
mainmenu_option next_comment
comment 'Processor type and features'
choice 'Processor family' \
- "386 CONFIG_M386 \
- 486/Cx486 CONFIG_M486 \
- Pentium/K5/5x86/6x86 CONFIG_M586 \
- PPro/K6/6x86MX CONFIG_M686" Pentium
+ "3 CONFIG_M386 \
+ 4 CONFIG_M486 \
+ 5 CONFIG_M586 \
+ 6/? CONFIG_M686" 3
bool 'Math emulation' CONFIG_MATH_EMULATION
endmenu
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu