Problems with flickering pixels
Hi,
I have installed linux on my A2000 some time ago (latest update from Woody
3.0R2). Something I still have problems with is the display. The console as
well as X11 show some flickering pixels - some black pixels from the
background are flickering white, some white pixels from the characters are
flickering black. Scrolling of text lines on the console sometimes messes
up whole lines of characters. Many pixels are inverted, the text looks very
scrambled.
I had a similar problem with flickering pixels on a PC many years ago. It
came out that the chipset was overclocking the bus to the graphics board.
Could be stopped by changing the settings in the BIOS.
In case of my Amiga, it does not seem to be a hardware problem. The display
looks perfectly fine under AmigaOS.
Any ideas, what may cause the problem under linux? Even more important, any
idea how to stop it?
My configuration is: A2000 with Blizzard 2060 (68060, 50 MHz), Picasso II
graphics board. I have attached an extract from dmesg at the end of this
message.
Best Regards,
Peter
#### output of dmesg #########
Linux version 2.2.20 (root@sparks) (gcc version 2.7.2.3) #1 Mon Mar 11
23:09:50 GMT 2002
Amiga hardware found: [A2000] VIDEO BLITTER AUDIO FLOPPY KEYBOARD MOUSE
SERIAL PARALLEL A2000_CLK CHIP_RAM PAULA DENISE_HR AGNUS_HR_PAL ZORRO
Console: colour dummy device 80x25
Calibrating delay loop... 99.73 BogoMIPS
Memory: 62676k/65024k available (1260k kernel code, 1012k data, 76k init)
Dentry hash table entries: 8192 (order 4, 64k)
Buffer cache hash table entries: 65536 (order 6, 256k)
Page cache hash table entries: 16384 (order 4, 64k)
kmem_create: Forcing size word alignment - filp
VFS: Diskquotas version dquot_6.4.0 initialized
kmem_create: Forcing size word alignment - dquot
POSIX conformance testing by UNIFIX
Zorro: Probing AutoConfig expansion devices: 5 devices
Linux NET4.0 for Linux 2.2
Based upon Swansea University Computer Society NET3.039
kmem_create: Forcing size word alignment - sock
kmem_create: Forcing size word alignment - skbuff_head_cache
NET4: Unix domain sockets 1.0 for Linux NET4.0.
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP
kmem_create: Forcing size word alignment - tcp_open_request
kmem_create: Forcing size word alignment - tcp_tw_bucket
TCP: Hash tables configured (ehash 65536 bhash 65536)
Initializing RT netlink socket
Starting kswapd v 1.5
clgen: Driver for Cirrus Logic based graphic boards, v1.4 ?
clgen: Picasso II board detected; RAM (2 MB) at $200000, REG at $ec0000
clgen: This board has 2097152 bytes of DRAM memory
Console: switching to colour frame buffer device 80x30
fb1: Amiga ECS frame buffer device, using 640K of video memory
M68K Serial driver version 1.01
ttyS0 at 0x80dff018: Amiga builtin
pty: 256 Unix98 ptys configured
<snip>
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