Bug 9614

Summary: [PATCH] Fix buggy MMX check for non-SSE AMD cpus
Product: xorg Reporter: Dan Williams <dcbw>
Component: Server/GeneralAssignee: Xorg Project Team <xorg-team>
Status: RESOLVED FIXED QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: high CC: ajax, lars, soren.sandmann
Version: unspecified   
Hardware: x86 (IA32)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Bug Depends on:    
Bug Blocks: 8888    
Attachments:
Description Flags
Correctly detect MMX and MMX extensions on AMD and Geode CPUs none

Description Dan Williams 2007-01-11 10:33:05 UTC 
There are two fixes here:

1) s/result/features - the code needs to be checking 'features' here, not
'result'.  Result is the actual cpuflags; features is the condensed set of
things pixman cares about.  Obviously if MMX = 0x1, (result & MMX) will never
give what we want here since for result the MMX bit is 23.

2) On the AMD Geode processor, which has MMX and MMX extensions, just checking
"AuthenticAMD" is not correct.  We need to check for "Geode by NSC" instead.

Credit for the fixes in this patch goes to:

Marco Gritti <mpg at redhat dot com>
Jordan Crouse <jordan dot crouse at amd dot com>
Comment 1 Dan Williams 2007-01-11 10:33:42 UTC 
Created attachment 8372 [details] [review]
Correctly detect MMX and MMX extensions on AMD and Geode CPUs
Comment 2 Søren Sandmann Pedersen 2007-02-06 14:55:09 UTC 
Fixed in HEAD, but this should be considered for 7.2 as well,
so adding it as a blocker.
Comment 3 Daniel Stone 2007-02-27 01:35:37 UTC 
Sorry about the phenomenal bug spam, guys.  Adding xorg-team@ to the QA contact so bugs don't get lost in future.
Comment 4 Adam Jackson 2007-04-08 13:39:51 UTC 
Move to 7.3 tracker.
Comment 5 Eric Anholt 2007-08-20 15:25:47 UTC 
pushed to 1.3 branch as well.

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