powerpc/powernv/npu-dma: Add explicit flush when sending an ATSD

Browse source

NPU2 requires an extra explicit flush to an active GPU PID when
sending address translation shoot downs (ATSDs) to reliably flush the
GPU TLB. This patch adds just such a flush at the end of each sequence
of ATSDs.

We can safely use PID 0 which is always reserved and active on the
GPU. PID 0 is only used for init_mm which will never be a user mm on
the GPU. To enforce this we add a check in pnv_npu2_init_context()
just in case someone tries to use PID 0 on the GPU.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
[mpe: Use true/false for bool literals]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

...

This commit is contained in:

Alistair Popple 2017-06-20 18:37:28 +10:00 • committed by Michael Ellerman

parent bf05fc25f2

commit bbd5ff50af

1 changed files with 65 additions and 29 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

94

arch/powerpc/platforms/powernv/npu-dma.c

View file