K6-II/K6-II: enable X86_USE_3DNOW

RFC PATCH In review Adrian Bunk 5 participants 7 messages Apr 14, 2003 – Apr 15, 2003

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Adrian Bunk

author

2003-04-14 22:10 UTC #0 lore raw

RFC PATCH 1/1 K6-II/K6-II: enable X86_USE_3DNOW

If my patch is wrong and this is a RTFM please give me a hint where to find the "M".

The AMD K6-II and K6-III do support 3DNow!

The patch below adds a new option for the AMD K6-II and K6-III and enables CONFIG_X86_USE_3DNOW.

I'm currently running 2.5.67 with this patch applied on my K6-II.

Questions:
Is it really correct to enable CONFIG_X86_USE_3DNOW? Is the -march=k6-2 correct?

TIA
Adrian

arch/i386/Kconfig renamed from arch/i386/Kconfig.old +17 -9

@@ -128,7 +128,8 @@
 	  - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
 	  - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
 	  - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
-	  - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
+	  - "K6" for the AMD K6.
+	  - "K6_2" for the AMD K6-II and K6-III (aka K6-3D).
 	  - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
 	  - "Crusoe" for the Transmeta Crusoe series.
 	  - "Winchip-C6" for original IDT Winchip.

@@ -200,12 +201,19 @@
 	  optimizations.
 
 config MK6
-	bool "K6/K6-II/K6-III"
+	bool "K6"
 	help
-	  Select this for an AMD K6-family processor.  Enables use of
-	  some extended instructions, and passes appropriate optimization
+	  Select this for an AMD K6 processor.  Enables use of some
+	  extended instructions, and passes appropriate optimization
 	  flags to GCC.
 
+config MK6_2
+	bool "K6-II/K6-III"
+	help
+	  Select this for an AMD K6-II and K6-III processors.  Enables
+	  use of some extended instructions, and passes appropriate
+	  optimization flags to GCC.
+
 config MK7
 	bool "Athlon/Duron/K7"
 	help

@@ -289,7 +297,7 @@
 config X86_L1_CACHE_SHIFT
 	int
 	default "4" if MELAN || M486 || M386
-	default "5" if MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCRUSOE || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2
+	default "5" if MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCRUSOE || MCYRIXIII || MK6 || MK6_2 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2
 	default "6" if MK7 || MK8
 	default "7" if MPENTIUM4

@@ -335,7 +343,7 @@
 
 config X86_ALIGNMENT_16
 	bool
-	depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2
+	depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || MK6_2 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2
 	default y
 
 config X86_GOOD_APIC

@@ -350,12 +358,12 @@
 
 config X86_USE_PPRO_CHECKSUM
 	bool
-	depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2
+	depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MK6_2 || MPENTIUM4 || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2
 	default y
 
 config X86_USE_3DNOW
 	bool
-	depends on MCYRIXIII || MK7
+	depends on MCYRIXIII || MK6_2 || MK7
 	default y
 
 config X86_OOSTORE

@@ -478,7 +486,7 @@
 
 config X86_TSC
 	bool
-	depends on (MWINCHIP3D || MWINCHIP2 || MCRUSOE || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2) && !X86_NUMAQ
+	depends on (MWINCHIP3D || MWINCHIP2 || MCRUSOE || MCYRIXIII || MK7 || MK6 || MK6_2 || MPENTIUM4 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2) && !X86_NUMAQ
 	default y
 
 config X86_MCE

arch/i386/Makefile renamed from arch/i386/Makefile.old +1 -0

@@ -39,6 +39,7 @@
 cflags-$(CONFIG_MPENTIUMIII)	+= $(call check_gcc,-march=pentium3,-march=i686)
 cflags-$(CONFIG_MPENTIUM4)	+= $(call check_gcc,-march=pentium4,-march=i686)
 cflags-$(CONFIG_MK6)		+= $(call check_gcc,-march=k6,-march=i586)
+cflags-$(CONFIG_MK6_2)		+= $(call check_gcc,-march=k6-2,-march=i586)
 cflags-$(CONFIG_MK7)		+= $(call check_gcc,-march=athlon,-march=i686 $(align)-functions=4)
 cflags-$(CONFIG_MK8)		+= $(call check_gcc,-march=k8,$(call check_gcc,-march=athlon,-march=i686 $(align)-functions=4))
 cflags-$(CONFIG_MCRUSOE)	+= -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0

include/asm-i386/module.h renamed from include/asm-i386/module.h.old +2 -0

@@ -30,6 +30,8 @@
 #define MODULE_PROC_FAMILY "PENTIUM4 "
 #elif defined CONFIG_MK6
 #define MODULE_PROC_FAMILY "K6 "
+#elif defined CONFIG_MK6_2
+#define MODULE_PROC_FAMILY "K6II "
 #elif defined CONFIG_MK7
 #define MODULE_PROC_FAMILY "K7 "
 #elif defined CONFIG_MK8

Dave Jones

2003-04-14 22:16 UTC #1 lore raw

Quoted 4 lines · Adrian Bunk

If my patch is wrong and this is a RTFM please give me a hint where to find the "M".
The AMD K6-II and K6-III do support 3DNow!

The 3dnow memory copies aren't a win on anything
earlier than an Athlon iirc.

Dave

Alan Cox

2003-04-14 22:53 UTC #2 lore raw

Quoted 8 lines · Dave Jones

Quoted 4 lines · Adrian Bunk
If my patch is wrong and this is a RTFM please give me a hint where to find the "M".
The AMD K6-II and K6-III do support 3DNow!
The 3dnow memory copies aren't a win on anything
earlier than an Athlon iirc.

Under 1% on a K6. The processor is so horribly memory bound the actual copy function is borderline irrelevant. If its not in the K6-III cache its not arriving in a hurry

Adrian Bunk

author

2003-04-15 19:25 UTC #3 lore raw

Quoted 5 lines · Alan Cox

Quoted 4 lines · Dave Jones
Quoted 3 lines · Adrian Bunk
If my patch is wrong and this is a RTFM please give me a hint where to find the "M".

Quoted 8 lines

Quoted 4 lines
Quoted 1 line
The AMD K6-II and K6-III do support 3DNow!
The 3dnow memory copies aren't a win on anything
earlier than an Athlon iirc.
Under 1% on a K6. The processor is so horribly memory bound the actual copy function is borderline irrelevant. If its not in the K6-III cache its not arriving in a hurry

Ah thanks, this is the information I didn't know.

cu
Adrian

Signature · 4 lines

       "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

Robert Love

2003-04-14 22:37 UTC #4 lore raw

In reply to Adrian Bunk

Quoted 2 lines · Adrian Bunk

If my patch is wrong and this is a RTFM please give me a hint where to find the "M".

Patch looks right...

Quoted 2 lines

Questions:
Is it really correct to enable CONFIG_X86_USE_3DNOW?

If you are right that the K6-2 and K6-3D support 3DNow!, then yes. At least its "correct" but it may not be optimal: I seem to recall 3DNow memory copies were not worthwhile on anything before an Athlon. Double check that, though.

Quoted 1 line

Is the -march=k6-2 correct?

Yes. Even if the above is true, splitting the K6 out like this is useful for the extra -march here. It certainly does not hurt (picking the original K6 will give proper support for the whole family, in needed).

Robert Love

Paweł Gołaszewski

2003-04-15 08:38 UTC #5 lore raw

Quoted 2 lines · Robert Love

Quoted 1 line
Questions: Is it really correct to enable CONFIG_X86_USE_3DNOW?
If you are right that the K6-2 and K6-3D support 3DNow!, then yes.

Yes, it does.

Signature · 4 lines

pozdr.  Paweł Gołaszewski        
---------------------------------
worth to see: http://www.againsttcpa.com/
CPU not found - software emulation...

Adrian Bunk

author

2003-04-15 19:27 UTC #6 lore raw

In reply to Robert Love

Quoted 7 lines · Robert Love

Quoted 2 lines · Adrian Bunk
If my patch is wrong and this is a RTFM please give me a hint where to find the "M".
Patch looks right...

Quoted 7 lines

Quoted 2 lines
Questions:
Is it really correct to enable CONFIG_X86_USE_3DNOW?
If you are right that the K6-2 and K6-3D support 3DNow!, then yes. At least its "correct" but it may not be optimal: I seem to recall 3DNow memory copies were not worthwhile on anything before an Athlon. Double check that, though.

It does, but Alan already explained why it doesn't make a difference.

Quoted 8 lines

Quoted 1 line
Is the -march=k6-2 correct?
Yes. Even if the above is true, splitting the K6 out like this is useful for the extra -march here. It certainly does not hurt (picking the original K6 will give proper support for the whole family, in needed).
From a quick look of the gcc-3.2.2 sources it seems that except for the

3DNow! support gcc doesn't differenciate between K6 and K6-II, so this change alone doesn't seem to make it worth adding a new processor type.

Quoted 1 line

Robert Love

cu
Adrian

Signature · 4 lines

       "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