Messages in this thread |  | | Date | Thu, 20 Sep 2001 13:59:43 +0200 | From | Kurt Garloff <> | Subject | Re: [prelim-PATCH] Enable SSE on K7 without BIOS support. |
| |
On Wed, Sep 19, 2001 at 11:30:41PM -0400, John Clemens wrote: > diff -u --recursive linux-orig/arch/i386/kernel/setup.c linux/arch/i386/kernel/setup.c > --- linux-orig/arch/i386/kernel/setup.c Wed Sep 19 22:49:11 2001 > +++ linux/arch/i386/kernel/setup.c Wed Sep 19 22:51:34 2001 > @@ -1272,6 +1272,14 @@ > > case 6: /* An Athlon/Duron. We can trust the BIOS probably */ > mcheck_init(c); > + if (c->x86_model == 6 || c->x86_model == 7) { > + rdmsr(MSR_K7_HWCR, l, h); > + if ( (h|l) != 0 ) { > + printk(KERN_INFO "Palomino/Morgan: Enabling K7/SSE support (your BIOS didn't..)\n"); > + wrmsr(MSR_K7_HWCR, 0, 0); > + set_bit(X86_FEATURE_XMM, &c->x86_capability);
After you enabled it via HWCR, cpuid should report the SSE capability, no? You should check it and not unconditionally enable XMM/SSE support flag, otherwise it may break on some CPU models.
Regards, -- Kurt Garloff <garloff@suse.de> Eindhoven, NL GPG key: See mail header, key servers Linux kernel development SuSE GmbH, Nuernberg, DE SCSI, Security [unhandled content-type:application/pgp-signature] |  |