[R300 and other radeons] MergedFB lockups
volodya at mindspring.com
Fri Feb 18 17:06:53 PST 2005
I think I found the cause of lockups in VB mode - they were due to cursor
updating function in radeon_mergedfb.c calling OUTREGP() which in turn
When silken mouse is enabled this function could be called at any time
which would do *bad* things when CP engine is active.
The fix of putting RADEONWaitForIdleMMIO() works fine on my setup.
I have *no* idea why this worked with immediate mode at all and why no
issues were reported by R200 and Radeon users (well, I only looked through
the mailing lists, perhaps there is something on bugzilla but I don't know
how to use that efficiently)
Also, I have no idea why the code in radeon_cursor.c that writes images
directly into framebuffer memory works - according to the manual any
writes into framebuffer while GUI is active should cause a hard lock.
However, I could not produce any lockups with it, and so left it as is.
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