gpu: nvgpu: hal for timestamps correlation

In order to perform timestamps correlation for FECS
traces, we need to collect GPU / GPU timestamps
samples. In virtualization case, it is possible for
a guest to get GPU timestamps by using read_ptimer.
However, if the CPU timestamp is read on guest side,
and the GPU timestamp is read on vm-server side,
then it introduces some latency that will create an
artificial offset for GPU timestamps (~2 us in
average). For better CPU / GPU timestamps correlation,
Added a command to collect all timestamps on vm-server
side.

Bug 1900475

Change-Id: Idfdc6ae4c16c501dc5e00053a5b75932c55148d6
Signed-off-by: Thomas Fleury <tfleury@nvidia.com>
Reviewed-on: http://git-master/r/1472447
(cherry picked from commit 56f56b5cd9d2e75cf7d2613b5e115bfebdbee0ce)
Reviewed-on: http://git-master/r/1489183
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gm20b/bus_gm20b.c b/drivers/gpu/nvgpu/gm20b/bus_gm20b.c
index 7b414196..39778c55 100644
--- a/drivers/gpu/nvgpu/gm20b/bus_gm20b.c
+++ b/drivers/gpu/nvgpu/gm20b/bus_gm20b.c
@@ -58,5 +58,6 @@ void gm20b_init_bus(struct gpu_ops *gops)
         gops->bus.init_hw = gk20a_bus_init_hw;
         gops->bus.isr = gk20a_bus_isr;
         gops->bus.read_ptimer = gk20a_read_ptimer;
+        gops->bus.get_timestamps_zipper = gk20a_get_timestamps_zipper;
         gops->bus.bar1_bind = gm20b_bus_bar1_bind;
 }