Messages in this thread | | | Date | Sun, 5 Aug 2018 23:51:50 +0200 | From | Pavel Machek <> | Subject | Re: framebuffer corruption due to overlapping stp instructions on arm64 |
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Hi!
> > Can you run the test program on x86 using the similar framebuffer > > setup? Does doing two writes (one aligned and one unaligned but > > overlapping with previous one) cause the same issue? I suspect it > > does, then using memcpy for frame buffers is wrong.
I'm pretty sure it will work ok on x86.
> Overlapping unaligned writes work on x86 - they have to, because of > backward compatibility.
It is not that easy. 8086s (and similar) did not have MTRRs and PATs either. Overlapping unaligned writes _on main memory_, _with normal MTRR settings_ certainly work ok on x86.
Chances is memory type can be configured to work similar way on your ARM/PCIe case?
> 8086, 80286 and 80386 didn't have any cache at all.
386s had cache (but not on die). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html [unhandled content-type:application/pgp-signature] | |