android_kernel_xiaomi_sdm845/drivers/gpu
Ben Skeggs dc8d76cac9 drm/nv50: prevent a possible ctxprog hang
The below is mainly an educated guess at what's going on, docs would
sure be handy...  NVIDIA? :P

It appears it's possible for a ctxprog to run even while a GPU exception
is pending.  The GF8 and up ctxprogs appear to have a small snippet of
code which detects this, and stalls the ctxprog until it's been handled,
which essentially looks like:

	if (r2 & 0x00008000) {
		r0 |= 0x80000000;
		while (r0 & 0x80000000) {}
	}

I don't know of any way that flag would get cleared unless the driver
intervenes (and indeed, in the cases I've seen the hang, nothing steps
in to automagically clear it for us).  This patch causes the driver to
clear the flag during the PGRAPH IRQ handler.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2010-01-11 14:41:16 +10:00
..
drm drm/nv50: prevent a possible ctxprog hang 2010-01-11 14:41:16 +10:00
vga PCI/vgaarb: cleanup some warnings + cleanup some comments. 2009-09-09 13:29:41 -07:00
Makefile PCI/GPU: implement VGA arbitration on Linux 2009-09-09 13:29:36 -07:00