[R300 and other radeons] MergedFB lockups

[Alex Deucher]

On Fri, 18 Feb 2005 20:06:53 -0500 (EST), Vladimir Dergachev
<volodya at mindspring.com> wrote:
> 
> 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
> called INREG.
> 
> 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)

I've never had any reports of this kind that I can think of for radeon or r200.

> 
> 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.
> 

Does using the overlay also cause a lockup?  there are some non-idled
INREGs in there as well.  I've never had a problem with them on r100
or r200 though.

Alex