From c3ed68143b9e553bdcf8bc93758dd98a7dc14be1 Mon Sep 17 00:00:00 2001
From: Srinivas Ramachandran <srinivasra@nvidia.com>
Date: Thu, 1 Aug 2019 11:42:57 -0700
Subject: [PATCH] nvethernet: Add IOCTL handler to config loopback mode

MODS tests use private IOCTL to configure MAC loopback mode.
Add a priv ioctl handler to support this in nvethernet driver.
nvethernet driver also has a sysfs knob to configure loopback.

Bug 2665785

Change-Id: I7f488fe81a0772a0881dbba48592bbcd11205dbf
Signed-off-by: Srinivas Ramachandran <srinivasra@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2166181
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
---
 .../net/ethernet/nvidia/nvethernet/ioctl.c    | 59 +++++++++++++++++++
 .../net/ethernet/nvidia/nvethernet/ioctl.h    |  1 +
 2 files changed, 60 insertions(+)

diff --git a/drivers/net/ethernet/nvidia/nvethernet/ioctl.c b/drivers/net/ethernet/nvidia/nvethernet/ioctl.c
index 20c5ae4f..085de6ad 100644
--- a/drivers/net/ethernet/nvidia/nvethernet/ioctl.c
+++ b/drivers/net/ethernet/nvidia/nvethernet/ioctl.c
@@ -564,6 +564,62 @@ static int ether_config_l2_da_filter(struct net_device *dev,
 	return ret;
 }
 
+/**
+ *	ether_config_loopback_mode- This function is invoked by ioctl
+ *	when user issues an ioctl command to enable/disable MAC loopback mode.
+ *
+ *	@dev: pointer to net device structure.
+ *	@flags: flag to indicate whether MAC loopback mode to be enabled or
+ *	disabled.
+ *
+ *	Algorithm:
+ *	1) check if loopback mode enalbed/disable already and return success.
+ *	2) OSI call to configure loopback mode in HW.
+ *
+ *	Dependencies: MAC and PHY need to be initialized.
+ *
+ *	Protection: None.
+ *
+ *	Return 0- sucessful, Negative - error
+ */
+static int ether_config_loopback_mode(struct net_device *ndev,
+				      unsigned int flags)
+{
+	struct ether_priv_data *pdata = netdev_priv(ndev);
+	struct osi_core_priv_data *osi_core = pdata->osi_core;
+	int ret = 0;
+
+	if ((flags && (pdata->mac_loopback_mode == OSI_ENABLE)) ||
+	    (!flags && (pdata->mac_loopback_mode == OSI_DISABLE))) {
+		dev_info(pdata->dev, "Loopback mode is already configured\n");
+		return ret;
+	}
+
+	if (flags) {
+		netif_carrier_on(ndev);
+		ret = osi_config_mac_loopback(osi_core, OSI_ENABLE);
+		if (ret < 0) {
+			dev_err(pdata->dev,
+				"Failed to enable MAC Loopback\n");
+		} else {
+			pdata->mac_loopback_mode = OSI_ENABLE;
+			dev_info(pdata->dev, "MAC loopback enabled\n");
+		}
+	} else {
+		netif_carrier_off(ndev);
+		ret = osi_config_mac_loopback(osi_core, OSI_DISABLE);
+		if (ret < 0) {
+			dev_err(pdata->dev,
+				"Failed to disable MAC Loopback\n");
+		} else {
+			pdata->mac_loopback_mode = OSI_DISABLE;
+			dev_info(pdata->dev, "MAC loopback disabled\n");
+		}
+	}
+
+	return ret;
+}
+
 /**
  *	ether_priv_ioctl - Handle private IOCTLs
  *	@ndev: network device structure
@@ -641,6 +697,9 @@ int ether_handle_priv_ioctl(struct net_device *ndev,
 	case EQOS_L2_DA_FILTERING_CMD:
 		ret = ether_config_l2_da_filter(ndev, &ifdata);
 		break;
+	case ETHER_CONFIG_LOOPBACK_MODE:
+		ret = ether_config_loopback_mode(ndev, ifdata.if_flags);
+		break;
 	default:
 		break;
 	}
diff --git a/drivers/net/ethernet/nvidia/nvethernet/ioctl.h b/drivers/net/ethernet/nvidia/nvethernet/ioctl.h
index 09de4e7f..f027bbb2 100644
--- a/drivers/net/ethernet/nvidia/nvethernet/ioctl.h
+++ b/drivers/net/ethernet/nvidia/nvethernet/ioctl.h
@@ -37,6 +37,7 @@
 /* L2 DA filtering */
 #define EQOS_L2_DA_FILTERING_CMD	35
 #define ETHER_CONFIG_ARP_OFFLOAD	36
+#define ETHER_CONFIG_LOOPBACK_MODE	40
 #define ETHER_GET_AVB_ALGORITHM		46
 
 /**