[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-kernel
Subject:    Re: 2.2.0pre1 OOPS on boot.
From:       "Theodore Y. Ts'o" <tytso () MIT ! EDU>
Date:       1998-12-31 21:36:05
[Download RAW message or body]

   From: torvalds@transmeta.com (Linus Torvalds)
   Date: 	30 Dec 1998 02:32:43 GMT

   It seems that the Cyrix chips do not do "rdtsc", even when they call
   themselves 686's. 

   We may need to have a special case for chips without "rdtsc".

Or simply use a run-time check for rdtsc (this example is from the
/dev/random driver):

        if (boot_cpu_data.x86_capability & X86_FEATURE_TSC) {
                __u32 high;
                __asm__(".byte 0x0f,0x31"
                        :"=a" (time), "=d" (high));
	...

Now, if the Cyrix chips are pulling a Clinton and saying that they have
rdtsc without actually having one, then obviously this won't
work.... (but then, they don't deserve to be supported, so...)

						- Ted

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

[prev in list] [next in list] [prev in thread] [next in thread]