ice: Add code for DCB initialization part 1/4

This patch introduces a skeleton for ice_init_pf_dcb, the top level
function for DCB initialization. Subsequent patches will add to this
DCB init flow.

In this patch, ice_init_pf_dcb checks if DCB is a supported capability.
If so, an admin queue call to start the LLDP and DCBx in firmware is
issued. If not, an error is reported. Note that we don't fail the driver
init if DCB init fails.

Reviewed-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ice/Makefile

@@ -17,3 +17,4 @@ ice-y := ice_main.o	\
 	 ice_txrx.o	\
 	 ice_ethtool.o
 ice-$(CONFIG_PCI_IOV) += ice_virtchnl_pf.o ice_sriov.o
+ice-$(CONFIG_DCB) += ice_dcb.o ice_dcb_lib.o

drivers/net/ethernet/intel/ice/ice.h

@@ -34,6 +34,7 @@
 #include "ice_devids.h"
 #include "ice_type.h"
 #include "ice_txrx.h"
+#include "ice_dcb.h"
 #include "ice_switch.h"
 #include "ice_common.h"
 #include "ice_sched.h"
@@ -321,6 +322,8 @@ enum ice_pf_flags {
 	ICE_FLAG_RSS_ENA,
 	ICE_FLAG_SRIOV_ENA,
 	ICE_FLAG_SRIOV_CAPABLE,
+	ICE_FLAG_DCB_CAPABLE,
+	ICE_FLAG_DCB_ENA,
 	ICE_FLAG_LINK_DOWN_ON_CLOSE_ENA,
 	ICE_PF_FLAGS_NBITS		/* must be last */
 };

drivers/net/ethernet/intel/ice/ice_adminq_cmd.h

@@ -1132,6 +1132,27 @@ struct ice_aqc_pf_vf_msg {
 	__le32 addr_low;
 };
 
+/* Start LLDP (direct 0x0A06) */
+struct ice_aqc_lldp_start {
+	u8 command;
+#define ICE_AQ_LLDP_AGENT_START		BIT(0)
+#define ICE_AQ_LLDP_AGENT_PERSIST_ENA	BIT(1)
+	u8 reserved[15];
+};
+
+/* Stop/Start LLDP Agent (direct 0x0A09)
+ * Used for stopping/starting specific LLDP agent. e.g. DCBx.
+ * The same structure is used for the response, with the command field
+ * being used as the status field.
+ */
+struct ice_aqc_lldp_stop_start_specific_agent {
+	u8 command;
+#define ICE_AQC_START_STOP_AGENT_M		BIT(0)
+#define ICE_AQC_START_STOP_AGENT_STOP_DCBX	0
+#define ICE_AQC_START_STOP_AGENT_START_DCBX	ICE_AQC_START_STOP_AGENT_M
+	u8 reserved[15];
+};
+
 /* Get/Set RSS key (indirect 0x0B04/0x0B02) */
 struct ice_aqc_get_set_rss_key {
 #define ICE_AQC_GSET_RSS_KEY_VSI_VALID	BIT(15)
@@ -1390,6 +1411,8 @@ struct ice_aq_desc {
 		struct ice_aqc_query_txsched_res query_sched_res;
 		struct ice_aqc_nvm nvm;
 		struct ice_aqc_pf_vf_msg virt;
+		struct ice_aqc_lldp_start lldp_start;
+		struct ice_aqc_lldp_stop_start_specific_agent lldp_agent_ctrl;
 		struct ice_aqc_get_set_rss_lut get_set_rss_lut;
 		struct ice_aqc_get_set_rss_key get_set_rss_key;
 		struct ice_aqc_add_txqs add_txqs;
@@ -1491,6 +1514,9 @@ enum ice_adminq_opc {
 	/* PF/VF mailbox commands */
 	ice_mbx_opc_send_msg_to_pf			= 0x0801,
 	ice_mbx_opc_send_msg_to_vf			= 0x0802,
+	/* LLDP commands */
+	ice_aqc_opc_lldp_start				= 0x0A06,
+	ice_aqc_opc_lldp_stop_start_specific_agent	= 0x0A09,
 
 	/* RSS commands */
 	ice_aqc_opc_set_rss_key				= 0x0B02,

drivers/net/ethernet/intel/ice/ice_dcb.c

@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Intel Corporation. */
+
+#include "ice_common.h"
+#include "ice_sched.h"
+#include "ice_dcb.h"
+
+/**
+ * ice_aq_start_lldp
+ * @hw: pointer to the HW struct
+ * @cd: pointer to command details structure or NULL
+ *
+ * Start the embedded LLDP Agent on all ports. (0x0A06)
+ */
+enum ice_status ice_aq_start_lldp(struct ice_hw *hw, struct ice_sq_cd *cd)
+{
+	struct ice_aqc_lldp_start *cmd;
+	struct ice_aq_desc desc;
+
+	cmd = &desc.params.lldp_start;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_lldp_start);
+
+	cmd->command = ICE_AQ_LLDP_AGENT_START;
+
+	return ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
+}
+
+/**
+ * ice_get_dcbx_status
+ * @hw: pointer to the HW struct
+ *
+ * Get the DCBX status from the Firmware
+ */
+u8 ice_get_dcbx_status(struct ice_hw *hw)
+{
+	u32 reg;
+
+	reg = rd32(hw, PRTDCB_GENS);
+	return (u8)((reg & PRTDCB_GENS_DCBX_STATUS_M) >>
+		    PRTDCB_GENS_DCBX_STATUS_S);
+}
+
+/**
+ * ice_aq_start_stop_dcbx - Start/Stop DCBx service in FW
+ * @hw: pointer to the HW struct
+ * @start_dcbx_agent: True if DCBx Agent needs to be started
+ *		      False if DCBx Agent needs to be stopped
+ * @dcbx_agent_status: FW indicates back the DCBx agent status
+ *		       True if DCBx Agent is active
+ *		       False if DCBx Agent is stopped
+ * @cd: pointer to command details structure or NULL
+ *
+ * Start/Stop the embedded dcbx Agent. In case that this wrapper function
+ * returns ICE_SUCCESS, caller will need to check if FW returns back the same
+ * value as stated in dcbx_agent_status, and react accordingly. (0x0A09)
+ */
+enum ice_status
+ice_aq_start_stop_dcbx(struct ice_hw *hw, bool start_dcbx_agent,
+		       bool *dcbx_agent_status, struct ice_sq_cd *cd)
+{
+	struct ice_aqc_lldp_stop_start_specific_agent *cmd;
+	enum ice_status status;
+	struct ice_aq_desc desc;
+	u16 opcode;
+
+	cmd = &desc.params.lldp_agent_ctrl;
+
+	opcode = ice_aqc_opc_lldp_stop_start_specific_agent;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, opcode);
+
+	if (start_dcbx_agent)
+		cmd->command = ICE_AQC_START_STOP_AGENT_START_DCBX;
+
+	status = ice_aq_send_cmd(hw, &desc, NULL, 0, cd);
+
+	*dcbx_agent_status = false;
+
+	if (!status &&
+	    cmd->command == ICE_AQC_START_STOP_AGENT_START_DCBX)
+		*dcbx_agent_status = true;
+
+	return status;
+}

drivers/net/ethernet/intel/ice/ice_dcb.h

@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2019, Intel Corporation. */
+
+#ifndef _ICE_DCB_H_
+#define _ICE_DCB_H_
+
+#include "ice_type.h"
+
+#define ICE_DCBX_STATUS_IN_PROGRESS	1
+#define ICE_DCBX_STATUS_DONE		2
+
+u8 ice_get_dcbx_status(struct ice_hw *hw);
+#ifdef CONFIG_DCB
+enum ice_status ice_aq_start_lldp(struct ice_hw *hw, struct ice_sq_cd *cd);
+enum ice_status
+ice_aq_start_stop_dcbx(struct ice_hw *hw, bool start_dcbx_agent,
+		       bool *dcbx_agent_status, struct ice_sq_cd *cd);
+#else /* CONFIG_DCB */
+static inline enum ice_status
+ice_aq_start_lldp(struct ice_hw __always_unused *hw,
+		  struct ice_sq_cd __always_unused *cd)
+{
+	return 0;
+}
+
+static inline enum ice_status
+ice_aq_start_stop_dcbx(struct ice_hw __always_unused *hw,
+		       bool __always_unused start_dcbx_agent,
+		       bool *dcbx_agent_status,
+		       struct ice_sq_cd __always_unused *cd)
+{
+	*dcbx_agent_status = false;
+
+	return 0;
+}
+#endif /* CONFIG_DCB */
+#endif /* _ICE_DCB_H_ */

drivers/net/ethernet/intel/ice/ice_dcb_lib.c

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019, Intel Corporation. */
+
+#include "ice_dcb_lib.h"
+
+/**
+ * ice_init_pf_dcb - initialize DCB for a PF
+ * @pf: pf to initiialize DCB for
+ */
+int ice_init_pf_dcb(struct ice_pf *pf)
+{
+	struct device *dev = &pf->pdev->dev;
+	struct ice_port_info *port_info;
+	struct ice_hw *hw = &pf->hw;
+
+	port_info = hw->port_info;
+
+	/* check if device is DCB capable */
+	if (!hw->func_caps.common_cap.dcb) {
+		dev_dbg(dev, "DCB not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	/* Best effort to put DCBx and LLDP into a good state */
+	port_info->dcbx_status = ice_get_dcbx_status(hw);
+	if (port_info->dcbx_status != ICE_DCBX_STATUS_DONE &&
+	    port_info->dcbx_status != ICE_DCBX_STATUS_IN_PROGRESS) {
+		bool dcbx_status;
+
+		/* Attempt to start LLDP engine. Ignore errors
+		 * as this will error if it is already started
+		 */
+		ice_aq_start_lldp(hw, NULL);
+
+		/* Attempt to start DCBX. Ignore errors as this
+		 * will error if it is already started
+		 */
+		ice_aq_start_stop_dcbx(hw, true, &dcbx_status, NULL);
+	}
+
+	return 0;
+}

drivers/net/ethernet/intel/ice/ice_dcb_lib.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2019, Intel Corporation. */
+
+#ifndef _ICE_DCB_LIB_H_
+#define _ICE_DCB_LIB_H_
+
+#include "ice.h"
+#include "ice_lib.h"
+
+#ifdef CONFIG_DCB
+int ice_init_pf_dcb(struct ice_pf *pf);
+#else
+static inline int ice_init_pf_dcb(struct ice_pf *pf)
+{
+	dev_dbg(&pf->pdev->dev, "DCB not supported\n");
+	return -EOPNOTSUPP;
+}
+#endif /* CONFIG_DCB */
+#endif /* _ICE_DCB_LIB_H_ */

drivers/net/ethernet/intel/ice/ice_hw_autogen.h

@@ -49,6 +49,9 @@
 #define PF_MBX_ATQLEN_ATQLEN_M			ICE_M(0x3FF, 0)
 #define PF_MBX_ATQLEN_ATQENABLE_M		BIT(31)
 #define PF_MBX_ATQT				0x0022E300
+#define PRTDCB_GENS				0x00083020
+#define PRTDCB_GENS_DCBX_STATUS_S		0
+#define PRTDCB_GENS_DCBX_STATUS_M		ICE_M(0x7, 0)
 #define GLFLXP_RXDID_FLAGS(_i, _j)		(0x0045D000 + ((_i) * 4 + (_j) * 256))
 #define GLFLXP_RXDID_FLAGS_FLEXIFLAG_4N_S	0
 #define GLFLXP_RXDID_FLAGS_FLEXIFLAG_4N_M	ICE_M(0x3F, 0)

drivers/net/ethernet/intel/ice/ice_main.c

@@ -7,6 +7,7 @@
 
 #include "ice.h"
 #include "ice_lib.h"
+#include "ice_dcb_lib.h"
 
 #define DRV_VERSION	"0.7.3-k"
 #define DRV_SUMMARY	"Intel(R) Ethernet Connection E800 Series Linux Driver"
@@ -2285,6 +2286,15 @@ ice_probe(struct pci_dev *pdev, const struct pci_device_id __always_unused *ent)
 
 	ice_init_pf(pf);
 
+	err = ice_init_pf_dcb(pf);
+	if (err) {
+		clear_bit(ICE_FLAG_DCB_CAPABLE, pf->flags);
+		clear_bit(ICE_FLAG_DCB_ENA, pf->flags);
+
+		/* do not fail overall init if DCB init fails */
+		err = 0;
+	}
+
 	ice_determine_q_usage(pf);
 
 	pf->num_alloc_vsi = hw->func_caps.guar_num_vsi;

drivers/net/ethernet/intel/ice/ice_type.h

@@ -148,6 +148,8 @@ struct ice_hw_common_caps {
 	/* RSS related capabilities */
 	u16 rss_table_size;		/* 512 for PFs and 64 for VFs */
 	u8 rss_table_entry_width;	/* RSS Entry width in bits */
+
+	u8 dcb;
 };
 
 /* Function specific capabilities */
@@ -277,6 +279,8 @@ struct ice_port_info {
 	struct ice_mac_info mac;
 	struct ice_phy_info phy;
 	struct mutex sched_lock;	/* protect access to TXSched tree */
+	/* LLDP/DCBX Status */
+	u8 dcbx_status;
 	u8 lport;
 #define ICE_LPORT_MASK		0xff
 	u8 is_vf;