msm: eva: Check files pointer before accessing it

There is a chance user process crashed when EVA is being used.
In that case, files pointer is set to NULL by kernel. Add
support of global timestamp support. Check wfi after pc ready.

Change-Id: Id01d07a79beec03e48885dd051549b5c39bc4846
Signed-off-by: George Shen <[email protected]>

msm/eva/cvp_hfi.c

@@ -2492,8 +2492,16 @@ static int __power_collapse(struct iris_hfi_device *device, bool force)
 
 		if (count == max_tries) {
 			dprintk(CVP_ERR,
-					"Skip PC. Core is not in right state (%#x, %#x)\n",
-					wfi_status, pc_ready);
+				"Skip PC. Core is not ready (%#x, %#x)\n",
+				wfi_status, pc_ready);
+			goto skip_power_off;
+		}
+	} else {
+		wfi_status = __read_register(device, CVP_WRAPPER_CPU_STATUS);
+		if (!(wfi_status & BIT(0))) {
+			dprintk(CVP_WARN,
+				"Skip PC as wfi_status (%#x) bit not set\n",
+				wfi_status);
 			goto skip_power_off;
 		}
 	}
@@ -3771,7 +3779,8 @@ static int __iris_power_on(struct iris_hfi_device *device)
 	dprintk(CVP_CORE, "Done with interrupt enabling\n");
 	device->intr_status = 0;
 	enable_irq(device->cvp_hal_data->irq);
-
+	__write_register(device,
+		CVP_WRAPPER_DEBUG_BRIDGE_LPI_CONTROL, 0x7);
 	pr_info(CVP_DBG_TAG "cvp (eva) powered on\n", "pwr");
 	return 0;
 

msm/eva/msm_cvp_buf.c

@@ -185,6 +185,9 @@ static struct file *msm_cvp_fget(unsigned int fd, struct task_struct *task,
 	struct files_struct *files = task->files;
 	struct file *file;
 
+	if (!files)
+		return NULL;
+
 	rcu_read_lock();
 loop:
 	file = fcheck_files(files, fd);