[lkml]   [2002]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH] Natsemi Geode GXn PM support and extended MMX
I am _not_ obsessed with power management.
I am _not_ obsessed with power management.
I am _not_ obsessed with power management.

Ok now that that's been cleared up, this patch enables suspend-on-hlt
(Geode GXn CPU power management) and enables the SUSP# pin on the CPU
which allows APM to function. Which brings me on to my next question, does
APM on Geode GXn work? The datasheet specifies that in order for the
processor to enter suspend mode (in response to SUSP# assertion) the first
criteria which must be met is that the USE_SUSP bit must be set (CCR2 bit
7). Part two of the patch simply enables extended MMX instructions for the

I'd be interested to hear of any problems with this.


Diffed against 2.4.19-pre2-ac3

--- arch/i386/kernel/setup.c.orig Sat Mar 16 09:45:46 2002
+++ arch/i386/kernel/setup.c Sat Mar 16 11:14:56 2002
@@ -71,6 +71,9 @@
* CacheSize bug workaround updates for AMD, Intel & VIA Cyrix.
* Dave Jones <>, September, October 2001.
+ * Added additional support for Natsemi/Cyrix Geode GXn CPUs,
+ * Enabled power management and extended MMX instructions.
+ * Zwane Mwaikambo <>, March 2002.

@@ -1509,6 +1512,12 @@

/* GXm supports extended cpuid levels 'ala' AMD */
if (c->cpuid_level == 2) {
+ /* Enable Natsemi MMX extensions */
+ setCx86(CX86_CCR7, getCx86(CX86_CCR7) | 1);
+ /* Suspend on halt power saving and enable #SUSP pin */
+ setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
get_model_name(c); /* get CPU marketing name */
* The 5510/5520 companion chips have a funky PIT
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:24    [W:0.051 / U:14.684 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site