gpu: nvgpu: Add support for XPU rail split

Check if CPU/GPU rails are joint, disable railgating if they are.
Add the DT support for T194 and T186 platforms.

Disable railgate_enable sysfs node update in the above condition.

Bug 200546450
Bug 200545711

Change-Id: I002488f6418805569b0ef0fc3032b58297adeafb
Signed-off-by: Debarshi Dutta <ddutta@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2185221
Reviewed-by: Rajkumar Kasirajan <rkasirajan@nvidia.com>
Tested-by: Rajkumar Kasirajan <rkasirajan@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Thomas Fleury <tfleury@nvidia.com>
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
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/os/linux/platform_gk20a_tegra.c b/drivers/gpu/nvgpu/os/linux/platform_gk20a_tegra.c
index 0977e63a..c39e4f0e 100644
--- a/drivers/gpu/nvgpu/os/linux/platform_gk20a_tegra.c
+++ b/drivers/gpu/nvgpu/os/linux/platform_gk20a_tegra.c
@@ -799,6 +799,7 @@ static int gk20a_tegra_probe(struct device *dev)
 
         if (joint_xpu_rail) {
                 nvgpu_log_info(g, "XPU rails are joint\n");
+                platform->can_railgate_init = false;
                 __nvgpu_set_enabled(g, NVGPU_CAN_RAILGATE, false);
         }