Bug 4169

Summary: Max pixel clock only 50MHz on CL-GD5436
Product: xorg Reporter: Ondrej Zary <linux>
Component: Driver/cirrusAssignee: Xorg Project Team <xorg-team>
Status: RESOLVED FIXED QA Contact: Xorg Project Team <xorg-team>
Severity: normal    
Priority: high    
Version: 6.8.2   
Hardware: x86 (IA32)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:

Description Ondrej Zary 2005-08-21 08:27:44 UTC 
The driver shows that max pixel clock is only 50MHz:

(==) CIRRUS(0): Min pixel clock is 12 MHz
(--) CIRRUS(0): Max pixel clock is 50 MHz

So I am unable to use 1024x768 modes. The card is QDI with Cirrus Logic
CL-GD5436 chipset with 2MB memory. I can use 1024x768/16-bit @ 75Hz in Windows
98 without any problems.
It can do a *lot* more than 50MHz according to this
http://www.xfree86.org/3.3.6/cirrus1.html and this 
http://www.chip.tomsk.ru/chip/chipdoc.nsf/0/0ab1cfcbad29a770c6256bf10073b1a9?OpenDocument
("pixel clock programmable up to 135 MHz and memory clock programmable up to 80
MHz").
Comment 1 Daniel Stone 2007-02-27 01:27:42 UTC 
Sorry about the phenomenal bug spam, guys.  Adding xorg-team@ to the QA contact so bugs don't get lost in future.
Comment 2 Jeremy Huddleston Sequoia 2011-10-17 01:42:55 UTC 
commit 3e5ebc4c1b9c2f751e50415b0d1bbb670c659eac
Author: Jeremy Huddleston <jeremyhu@apple.com>
Date:   Mon Oct 17 01:40:17 2011 -0700

    GD5436 timings are the same as GD5446
    
    Based on information from http://www.xfree86.org/3.3.6/cirrus1.html
    See: https://bugs.freedesktop.org/show_bug.cgi?id=4169
    
    Signed-off-by: Jeremy Huddleston <jeremyhu@apple.com>

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