Re: [PATCH] x86 boot time check for cpu features
On Fri, 3 Nov 2000, Brian Gerst wrote: > > That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. > > The MII is a different monster. > According to the docs on VIA's site, the MII's cpuid can still be turned > off, but it is on by default at reset. I wouldn't trust the BIOS to not > screw it up. Err, what? If it's on by default... A old BIOS that doesn't know about it won't switch it off. A BIOS that does know about it will leave it (or maybe offer an option to disable it) If neither of the above are true (Ie, a BIOS bug) and it's switched off by the time Linux boots, I think we'd have heard about it by now, as MII users would notice a lack of features. regards, Dave. -- | Dave Jones <[EMAIL PROTECTED]> http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
[EMAIL PROTECTED] wrote: > > Brian Gerst wrote... > >> I believe the MII always has CPUID enabled. It was the older Cyrixes > >> that did not. DaveJ is the guru.. > > Well, according to comments in bugs.h, some broken BIOSes disable cpuid. > > That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. > The MII is a different monster. According to the docs on VIA's site, the MII's cpuid can still be turned off, but it is on by default at reset. I wouldn't trust the BIOS to not screw it up. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Brian Gerst wrote... >> I believe the MII always has CPUID enabled. It was the older Cyrixes >> that did not. DaveJ is the guru.. > Well, according to comments in bugs.h, some broken BIOSes disable cpuid. That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. The MII is a different monster. d. -- | Dave Jones <[EMAIL PROTECTED]> http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote.. > > Hmm, after a bit more investigation, it appears that the Cyrix MII > > processors support cmov instructions, even though we currently don't > > compile for that processor with -march=i686. Please ignore this patch > > until I can come up with something better. > I believe the MII always has CPUID enabled. It was the older Cyrixes > that did not. That was my understanding also. d. -- | Dave Jones <[EMAIL PROTECTED]> http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: > > > Alan Cox wrote: > > > Q: are any of the things you test present in processors only after we > > > do magic 'cpuid' enable invocations ? > > > > Hmm, after a bit more investigation, it appears that the Cyrix MII > > processors support cmov instructions, even though we currently don't > > compile for that processor with -march=i686. Please ignore this patch > > until I can come up with something better. > > I believe the MII always has CPUID enabled. It was the older Cyrixes that did > not. DaveJ is the guru.. Well, according to comments in bugs.h, some broken BIOSes disable cpuid. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
> Alan Cox wrote: > > Q: are any of the things you test present in processors only after we > > do magic 'cpuid' enable invocations ? > > Hmm, after a bit more investigation, it appears that the Cyrix MII > processors support cmov instructions, even though we currently don't > compile for that processor with -march=i686. Please ignore this patch > until I can come up with something better. I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. DaveJ is the guru.. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: > Q: are any of the things you test present in processors only after we > do magic 'cpuid' enable invocations ? Hmm, after a bit more investigation, it appears that the Cyrix MII processors support cmov instructions, even though we currently don't compile for that processor with -march=i686. Please ignore this patch until I can come up with something better. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: > > > + lea cpuid_fail_msg, %si > > + callprtstr > > +1: jmp 1b > > +cpuid_fail_msg: > > + .string "Required CPU features are not present - compile kernel for the >proper CPU type." > > +cpuid_pass: > > Only one very minor suggestion > > 1: hlt > j 1b > > Q: are any of the things you test present in processors only after we > do magic 'cpuid' enable invocations ? AFAIK, none of the braindead chips have cmov instructions or PAE support (only PentiumPro+ and Athlon do). If someone can prove me wrong I'd like to know. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
> + lea cpuid_fail_msg, %si > + callprtstr > +1: jmp 1b > +cpuid_fail_msg: > + .string "Required CPU features are not present - compile kernel for the proper >CPU type." > +cpuid_pass: Only one very minor suggestion 1: hlt j 1b Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
+ lea cpuid_fail_msg, %si + callprtstr +1: jmp 1b +cpuid_fail_msg: + .string "Required CPU features are not present - compile kernel for the proper CPU type." +cpuid_pass: Only one very minor suggestion 1: hlt j 1b Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: + lea cpuid_fail_msg, %si + callprtstr +1: jmp 1b +cpuid_fail_msg: + .string "Required CPU features are not present - compile kernel for the proper CPU type." +cpuid_pass: Only one very minor suggestion 1: hlt j 1b Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? AFAIK, none of the braindead chips have cmov instructions or PAE support (only PentiumPro+ and Athlon do). If someone can prove me wrong I'd like to know. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? Hmm, after a bit more investigation, it appears that the Cyrix MII processors support cmov instructions, even though we currently don't compile for that processor with -march=i686. Please ignore this patch until I can come up with something better. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? Hmm, after a bit more investigation, it appears that the Cyrix MII processors support cmov instructions, even though we currently don't compile for that processor with -march=i686. Please ignore this patch until I can come up with something better. I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. DaveJ is the guru.. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote: Alan Cox wrote: Q: are any of the things you test present in processors only after we do magic 'cpuid' enable invocations ? Hmm, after a bit more investigation, it appears that the Cyrix MII processors support cmov instructions, even though we currently don't compile for that processor with -march=i686. Please ignore this patch until I can come up with something better. I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. DaveJ is the guru.. Well, according to comments in bugs.h, some broken BIOSes disable cpuid. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Alan Cox wrote.. Hmm, after a bit more investigation, it appears that the Cyrix MII processors support cmov instructions, even though we currently don't compile for that processor with -march=i686. Please ignore this patch until I can come up with something better. I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. That was my understanding also. d. -- | Dave Jones [EMAIL PROTECTED] http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
Brian Gerst wrote... I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. DaveJ is the guru.. Well, according to comments in bugs.h, some broken BIOSes disable cpuid. That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. The MII is a different monster. d. -- | Dave Jones [EMAIL PROTECTED] http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
[EMAIL PROTECTED] wrote: Brian Gerst wrote... I believe the MII always has CPUID enabled. It was the older Cyrixes that did not. DaveJ is the guru.. Well, according to comments in bugs.h, some broken BIOSes disable cpuid. That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. The MII is a different monster. According to the docs on VIA's site, the MII's cpuid can still be turned off, but it is on by default at reset. I wouldn't trust the BIOS to not screw it up. -- Brian Gerst - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86 boot time check for cpu features
On Fri, 3 Nov 2000, Brian Gerst wrote: That bug fix is for the earlier Cyrix 6x86 if I'm not mistaken. The MII is a different monster. According to the docs on VIA's site, the MII's cpuid can still be turned off, but it is on by default at reset. I wouldn't trust the BIOS to not screw it up. Err, what? If it's on by default... A old BIOS that doesn't know about it won't switch it off. A BIOS that does know about it will leave it (or maybe offer an option to disable it) If neither of the above are true (Ie, a BIOS bug) and it's switched off by the time Linux boots, I think we'd have heard about it by now, as MII users would notice a lack of features. regards, Dave. -- | Dave Jones [EMAIL PROTECTED] http://www.suse.de/~davej | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
