On 07/01/2020 15:30, Tomi Valkeinen wrote:
On 05/01/2020 22:37, Tony Lindgren wrote:
Hi,
- Tony Lindgren tony@atomide.com [200104 05:51]:
Just changing the alingment fixes the issue. Looks like the minimum alignment we currently allow is 128, I think 512 was the minimum that worked for me, so maybe the right fix would be to just change the minimum to 512 with no specific need to use 4096 for now.
So Matthijs and I chatted about this a bit on irc, and here's what we concluded so far:
- We have at least three different alignment needs for tiler
Linux use of tiler aligned to 128 bytes
SGX use of tiler aligned to 4096 bytes (or 512 bytes?)
Fast userspace mapping aligned to 4096 bytes
- The alignment need may need to be configured by the tiler consumer
in #1 above
The alignment need for SGX seems to be based on SGX MMU page size
The issue I'm seeing with stellarium on droid4 may be a stride
issue as about one out of 3 or 4 frames is OK and aligning to 512 also fixes the issue maybe because it happens to make multiple frames align to 4096
So let's wait on this patch until we have more info and know how the different alignments should be handled.
I don't know if these are related to the issue you have, and it's been a while since I looked at TILER, but two thoughts after looking at the thread:
- If the usergart is not used, the width of each line has to be expanded to be page size aligned,
right? Do the patches from Matthijs do this?
And immediately after pressing "send", I realized that aligning the start of the buffers to page size already accomplishes this...
Tomi