net: atlantic: implement media detect feature via phy tunables

Mediadetect is another name for the EDPD (energy detect power down).
This feature allows device to save extra power when no link is available.

PHY goes into the extreme power saving mode and only periodically wakes up
and checks for the link.

AQC devices has fixed check period of 6 seconds

The feature may increase linkup time.

Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c

@@ -923,6 +923,12 @@ static int aq_ethtool_get_phy_tunable(struct net_device *ndev,
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
 
 	switch (tuna->id) {
+	case ETHTOOL_PHY_EDPD: {
+		u16 *val = data;
+
+		*val = aq_nic->aq_nic_cfg.is_media_detect ? AQ_HW_MEDIA_DETECT_CNT : 0;
+		break;
+	}
 	case ETHTOOL_PHY_DOWNSHIFT: {
 		u8 *val = data;
 
@@ -943,6 +949,12 @@ static int aq_ethtool_set_phy_tunable(struct net_device *ndev,
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
 
 	switch (tuna->id) {
+	case ETHTOOL_PHY_EDPD: {
+		const u16 *val = data;
+
+		err = aq_nic_set_media_detect(aq_nic, *val);
+		break;
+	}
 	case ETHTOOL_PHY_DOWNSHIFT: {
 		const u8 *val = data;
 

drivers/net/ethernet/aquantia/atlantic/aq_hw.h

@@ -143,6 +143,8 @@ struct aq_stats_s {
 #define AQ_HW_LED_BLINK    0x2U
 #define AQ_HW_LED_DEFAULT  0x0U
 
+#define AQ_HW_MEDIA_DETECT_CNT 6000
+
 enum aq_priv_flags {
 	AQ_HW_LOOPBACK_DMA_SYS,
 	AQ_HW_LOOPBACK_PKT_SYS,
@@ -388,6 +390,8 @@ struct aq_fw_ops {
 
 	int (*set_downshift)(struct aq_hw_s *self, u32 counter);
 
+	int (*set_media_detect)(struct aq_hw_s *self, bool enable);
+
 	u32 (*get_link_capabilities)(struct aq_hw_s *self);
 
 	int (*send_macsec_req)(struct aq_hw_s *self,

drivers/net/ethernet/aquantia/atlantic/aq_nic.c

@@ -407,6 +407,8 @@ int aq_nic_init(struct aq_nic_s *self)
 		goto err_exit;
 	/* Restore default settings */
 	aq_nic_set_downshift(self, self->aq_nic_cfg.downshift_counter);
+	aq_nic_set_media_detect(self, self->aq_nic_cfg.is_media_detect ?
+				AQ_HW_MEDIA_DETECT_CNT : 0);
 
 	err = self->aq_hw_ops->hw_init(self->aq_hw,
 				       aq_nic_get_ndev(self)->dev_addr);
@@ -1421,6 +1423,31 @@ int aq_nic_set_downshift(struct aq_nic_s *self, int val)
 	return err;
 }
 
+int aq_nic_set_media_detect(struct aq_nic_s *self, int val)
+{
+	struct aq_nic_cfg_s *cfg = &self->aq_nic_cfg;
+	int err = 0;
+
+	if (!self->aq_fw_ops->set_media_detect)
+		return -EOPNOTSUPP;
+
+	if (val > 0 && val != AQ_HW_MEDIA_DETECT_CNT) {
+		netdev_err(self->ndev, "EDPD on this device could have only fixed value of %d\n",
+			   AQ_HW_MEDIA_DETECT_CNT);
+		return -EINVAL;
+	}
+
+	mutex_lock(&self->fwreq_mutex);
+	err = self->aq_fw_ops->set_media_detect(self->aq_hw, !!val);
+	mutex_unlock(&self->fwreq_mutex);
+
+	/* msecs plays no role - configuration is always fixed in PHY */
+	if (!err)
+		cfg->is_media_detect = !!val;
+
+	return err;
+}
+
 int aq_nic_setup_tc_mqprio(struct aq_nic_s *self, u32 tcs, u8 *prio_tc_map)
 {
 	struct aq_nic_cfg_s *cfg = &self->aq_nic_cfg;

drivers/net/ethernet/aquantia/atlantic/aq_nic.h

@@ -62,6 +62,7 @@ struct aq_nic_cfg_s {
 	bool is_lro;
 	bool is_qos;
 	bool is_ptp;
+	bool is_media_detect;
 	int downshift_counter;
 	enum aq_tc_mode tc_mode;
 	u32 priv_flags;
@@ -197,6 +198,7 @@ struct aq_nic_cfg_s *aq_nic_get_cfg(struct aq_nic_s *self);
 u32 aq_nic_get_fw_version(struct aq_nic_s *self);
 int aq_nic_set_loopback(struct aq_nic_s *self);
 int aq_nic_set_downshift(struct aq_nic_s *self, int val);
+int aq_nic_set_media_detect(struct aq_nic_s *self, int val);
 int aq_nic_update_interrupt_moderation_settings(struct aq_nic_s *self);
 void aq_nic_shutdown(struct aq_nic_s *self);
 u8 aq_nic_reserve_filter(struct aq_nic_s *self, enum aq_rx_filter_type type);

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c

@@ -633,6 +633,20 @@ static int aq_fw2x_set_downshift(struct aq_hw_s *self, u32 counter)
 	return err;
 }
 
+static int aq_fw2x_set_media_detect(struct aq_hw_s *self, bool on)
+{
+	u32 enable;
+	u32 offset;
+
+	if (self->fw_ver_actual < HW_ATL_FW_VER_MEDIA_CONTROL)
+		return -EOPNOTSUPP;
+
+	offset = offsetof(struct hw_atl_utils_settings, media_detect);
+	enable = on;
+
+	return hw_atl_write_fwsettings_dwords(self, offset, &enable, 1);
+}
+
 static u32 aq_fw2x_get_link_capabilities(struct aq_hw_s *self)
 {
 	int err = 0;
@@ -714,6 +728,7 @@ const struct aq_fw_ops aq_fw_2x_ops = {
 	.led_control        = aq_fw2x_led_control,
 	.set_phyloopback    = aq_fw2x_set_phyloopback,
 	.set_downshift      = aq_fw2x_set_downshift,
+	.set_media_detect   = aq_fw2x_set_media_detect,
 	.adjust_ptp         = aq_fw3x_adjust_ptp,
 	.get_link_capabilities = aq_fw2x_get_link_capabilities,
 	.send_macsec_req    = aq_fw2x_send_macsec_req,