From c983eec6257854eee63b687c06ed2144f62bfc64 Mon Sep 17 00:00:00 2001
From: Johnny Liu <johnliu@nvidia.com>
Date: Wed, 2 Aug 2023 09:52:01 +0000
Subject: [PATCH] drivers: pva: skip vpu load reading when suspended

WHen PVA is already suspended, there is no need to resume the device
through nvhost_module_busy and send mailbox request to PVA for VPU load
reading. It avoids switching CV power domain on and off.

Bug 4168798

Signed-off-by: Johnny Liu <johnliu@nvidia.com>
Change-Id: Ib9ec4d4ded2b96ee8f76267e190087612d1e0468
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/2946818
Reviewed-by: svcacv <svcacv@nvidia.com>
Reviewed-by: Ninad Malwade <nmalwade@nvidia.com>
Reviewed-by: Omar Nemri <onemri@nvidia.com>
GVS: Gerrit_Virtual_Submit <buildbot_gerritrpt@nvidia.com>
---
 drivers/video/tegra/host/pva/pva_debug.c | 26 ++++++++++++++++--------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/video/tegra/host/pva/pva_debug.c b/drivers/video/tegra/host/pva/pva_debug.c
index 172dee5d..68c5d26b 100644
--- a/drivers/video/tegra/host/pva/pva_debug.c
+++ b/drivers/video/tegra/host/pva/pva_debug.c
@@ -5,18 +5,21 @@
  * PVA Debug Information file
  */
 
+#include <linux/debugfs.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/debugfs.h>
-#include <linux/platform_device.h>
-#include <linux/interrupt.h>
 #include <linux/nvhost.h>
-#include <linux/uaccess.h>
-#include <linux/dma-mapping.h>
-#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
-#include "pva.h"
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
 #include <uapi/linux/nvpva_ioctl.h>
+
+#include "pva.h"
 #include "pva_vpu_ocd.h"
 #include "pva-fw-address-map.h"
 
@@ -249,8 +252,13 @@ static void update_vpu_stats(struct pva *pva, bool stats_enabled)
 		pva->vpu_util_info.stats_fw_buffer_va;
 	u64 *vpu_stats = pva->vpu_util_info.vpu_stats;
 
-	if (vpu_stats == 0)
-		goto err_out;
+#ifdef CONFIG_PM
+	if (pm_runtime_suspended(&pva->pdev->dev)) {
+		vpu_stats[0] = 0;
+		vpu_stats[1] = 0;
+		return;
+	}
+#endif
 
 	err = nvhost_module_busy(pva->pdev);
 	if (err < 0) {