4 files changed, 29 insertions, 9 deletions
diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
index 38e21cf7806e..dfdbfb025089 100644
--- a/drivers/misc/cxl/cxl.h
+++ b/drivers/misc/cxl/cxl.h
@@ -579,6 +579,7 @@ struct cxl {
 	bool perst_loads_image;
 	bool perst_select_user;
 	bool perst_same_image;
+	bool psl_timebase_synced;
 };
 
 int cxl_pci_alloc_one_irq(struct cxl *adapter);
diff --git a/drivers/misc/cxl/guest.c b/drivers/misc/cxl/guest.c
index 8213372de2b7..a83acf9f8cd9 100644
--- a/drivers/misc/cxl/guest.c
+++ b/drivers/misc/cxl/guest.c
@@ -1101,6 +1101,12 @@ struct cxl *cxl_guest_init_adapter(struct device_node *np, struct platform_devic
 	adapter->dev.release = release_adapter;
 	dev_set_drvdata(&pdev->dev, adapter);
 
+	/*
+	 * Hypervisor controls PSL timebase initialization (p1 register).
+	 * On FW840, PSL is initialized.
+	 */
+	adapter->psl_timebase_synced = true;
+
 	if ((rc = cxl_of_read_adapter_handle(adapter, np)))
 		goto err1;
 
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 94fd3f71f838..c6d5cf5e3793 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -394,22 +394,24 @@ static int init_implementation_adapter_regs(struct cxl *adapter, struct pci_dev
 #define TBSYNC_CNT(n) (((u64)n & 0x7) << (63-6))
 #define _2048_250MHZ_CYCLES 1
 
-static int cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
+static void cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
 {
 	u64 psl_tb;
 	int delta;
 	unsigned int retry = 0;
 	struct device_node *np;
 
+	adapter->psl_timebase_synced = false;
+
 	if (!(np = pnv_pci_get_phb_node(dev)))
-		return -ENODEV;
+		return;
 
 	/* Do not fail when CAPP timebase sync is not supported by OPAL */
 	of_node_get(np);
 	if (! of_get_property(np, "ibm,capp-timebase-sync", NULL)) {
 		of_node_put(np);
-		pr_err("PSL: Timebase sync: OPAL support missing\n");
-		return 0;
+		dev_info(&dev->dev, "PSL timebase inactive: OPAL support missing\n");
+		return;
 	}
 	of_node_put(np);
 
@@ -428,8 +430,8 @@ static int cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
 	do {
 		msleep(1);
 		if (retry++ > 5) {
-			pr_err("PSL: Timebase sync: giving up!\n");
-			return -EIO;
+			dev_info(&dev->dev, "PSL timebase can't synchronize\n");
+			return;
 		}
 		psl_tb = cxl_p1_read(adapter, CXL_PSL_Timebase);
 		delta = mftb() - psl_tb;
@@ -437,7 +439,8 @@ static int cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
 			delta = -delta;
 	} while (tb_to_ns(delta) > 16000);
 
-	return 0;
+	adapter->psl_timebase_synced = true;
+	return;
 }
 
 static int init_implementation_afu_regs(struct cxl_afu *afu)
@@ -1183,8 +1186,8 @@ static int cxl_configure_adapter(struct cxl *adapter, struct pci_dev *dev)
 	if ((rc = pnv_phb_to_cxl_mode(dev, OPAL_PHB_CAPI_MODE_SNOOP_ON)))
 		goto err;
 
-	if ((rc = cxl_setup_psl_timebase(adapter, dev)))
-		goto err;
+	/* Ignore error, adapter init is not dependant on timebase sync */
+	cxl_setup_psl_timebase(adapter, dev);
 
 	if ((rc = cxl_native_register_psl_err_irq(adapter)))
 		goto err;
diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c
index 25913c08794c..b043c20f158f 100644
--- a/drivers/misc/cxl/sysfs.c
+++ b/drivers/misc/cxl/sysfs.c
@@ -57,6 +57,15 @@ static ssize_t image_loaded_show(struct device *device,
 	return scnprintf(buf, PAGE_SIZE, "factory\n");
 }
 
+static ssize_t psl_timebase_synced_show(struct device *device,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct cxl *adapter = to_cxl_adapter(device);
+
+	return scnprintf(buf, PAGE_SIZE, "%i\n", adapter->psl_timebase_synced);
+}
+
 static ssize_t reset_adapter_store(struct device *device,
 				   struct device_attribute *attr,
 				   const char *buf, size_t count)
@@ -142,6 +151,7 @@ static struct device_attribute adapter_attrs[] = {
 	__ATTR_RO(psl_revision),
 	__ATTR_RO(base_image),
 	__ATTR_RO(image_loaded),
+	__ATTR_RO(psl_timebase_synced),
 	__ATTR_RW(load_image_on_perst),
 	__ATTR_RW(perst_reloads_same_image),
 	__ATTR(reset, S_IWUSR, NULL, reset_adapter_store),