[PATCH] x86 cpu selection (first hack)

J.A. Magallon
2002-05-30T22:50:22Z

Hi all.

After reading all the posts in the lista about this and thinking a bit,
here is the first attempt (just a try of the general aspect) of a new
cpu selection scheme. This post is mainly to see if I really understood
the scenario.

There were two ways to do this:

- Define a min/max cpu selecion. Both are a kbuild's 'choice'.
Problems: it generates a ton of symbols of the kind of CPU_MIN_INTEL_PENTIUM
or CPU_MAX_AMD_ATHLON. And you have to limit the 'max' choice to be
bigger than the first. This brings two problems: limiting the choices
on a 'choice' based on one other, and defining an 'order' in processors,
even between architectures.

- Make all and every cpu a checkbox, so you just say 'I want my kernel to
support this and that CPU'. This kills the problem of the ordering, and
adds one other advantage: you do not need to support intermediate CPUs,
like 'i want my kernel to run ok on pentium-mmx (my firewall) and on
p4 (my desktop). I will never run it on a PII, so do not include the
hacks for PII'. And of course, 'If I run my p-mmx capable on a friend's
PII and it eats his drive and burns his TV set, it is only _my_ fault'.

Patch follows, comments are welcome. Next step is to begin to order the logic,
but I wanted to ask first about this.

diff -ruN linux-2.4.19-pre9/arch/i386/config.in linux-2.4.19-pre9-cpu/arch/i386/config.in
--- linux-2.4.19-pre9/arch/i386/config.in 2002-05-29 01:18:23.000000000 +0200
+++ linux-2.4.19-pre9-cpu/arch/i386/config.in 2002-05-30 23:38:06.000000000 +0200
@@ -26,6 +26,12 @@

mainmenu_option next_comment
comment 'Processor type and features'
+bool 'New CPU selection scheme' CONFIG_CPU_SELECTION_NEW
+
+# CPUConfig
+if [ "$CONFIG_CPU_SELECTION_NEW" = "y" ]; then
+ source arch/i386/CPUConfig.in
+else
choice 'Processor family' \
"386 CONFIG_M386 \
486 CONFIG_M486 \
@@ -163,6 +169,7 @@
define_bool CONFIG_X86_USE_PPRO_CHECKSUM y
define_bool CONFIG_X86_OOSTORE y
fi
+fi

bool 'Machine Check Exception' CONFIG_X86_MCE

diff -ruN linux-2.4.19-pre9/arch/i386/CPUConfig.in linux-2.4.19-pre9-cpu/arch/i386/CPUConfig.in
--- linux-2.4.19-pre9/arch/i386/CPUConfig.in 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.4.19-pre9-cpu/arch/i386/CPUConfig.in 2002-05-31 00:28:31.000000000 +0200
@@ -0,0 +1,40 @@
+mainmenu_option next_comment
+comment 'CPU selection'
+
+comment 'Generic x86 CPUs'
+bool 'Generic support' CONFIG_VENDOR_GENERIC
+if [ "$CONFIG_VENDOR_GENERIC" = "y" ]; then
+
+ bool '386' CONFIG_CPU_GENERIC_386
+ bool '486' CONFIG_CPU_GENERIC_486
+ bool '586' CONFIG_CPU_GENERIC_586
+ bool '686' CONFIG_CPU_GENERIC_686
+
+else
+
+comment 'Intel CPUs'
+bool 'Intel support' CONFIG_VENDOR_INTEL
+if [ "$CONFIG_VENDOR_INTEL" = "y" ]; then
+ bool '386' CONFIG_CPU_INTEL_386
+ bool '486' CONFIG_CPU_INTEL_486
+ bool 'Pentium' CONFIG_CPU_INTEL_PENTIUM
+ bool 'PentiumMMX' CONFIG_CPU_INTEL_PENTIUMMMX
+ bool 'PentiumPro' CONFIG_CPU_INTEL_PENTIUMPRO
+ bool 'PentiumII/Celeron' CONFIG_CPU_INTEL_PENTIUM2
+ bool 'PentiumIII/Celeron(Coppermine)' CONFIG_CPU_INTEL_PENTIUM3
+ bool 'Pentium4' CONFIG_CPU_INTEL_PENTIUM4
+fi
+comment 'AMD CPUs'
+bool 'AMD support' CONFIG_VENDOR_AMD
+if [ "$CONFIG_VENDOR_AMD" = "y" ]; then
+ bool '386' CONFIG_CPU_AMD_386
+ bool '486' CONFIG_CPU_AMD_486
+ bool 'K5' CONFIG_CPU_AMD_K5
+ bool 'K6/K6II/K6III' CONFIG_CPU_AMD_K6
+ bool 'K7' CONFIG_CPU_AMD_K7
+ bool 'Athlon/Duron' CONFIG_CPU_AMD_ATHLON
+fi
+
+fi
+
+endmenu

--
J.A. Magallon # Let the source be with you...
mailto:jamagallon@able.es
Mandrake Linux release 8.3 (Cooker) for i586
Linux werewolf 2.4.19-pre9-jam1 #1 SMP jue may 30 00:48:49 CEST 2002 i686