--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2026 Intel Corporation */
+
+#include "ice_type.h"
+#include "ice_common.h"
+#include "ice_ptp_hw.h"
+#include "ice.h"
+#include "ice_cpi.h"
+
+/**
+ * ice_cpi_get_dest_dev - get destination PHY for given phy index
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ *
+ * Return: sideband queue destination PHY device.
+ */
+static enum ice_sbq_dev_id ice_cpi_get_dest_dev(struct ice_hw *hw, u8 phy)
+{
+ u8 curr_phy = hw->lane_num / hw->ptp.ports_per_phy;
+
+ /* In the driver, lanes 4..7 are in fact 0..3 on a second PHY.
+ * On a single complex E825C, PHY 0 is always destination device phy_0
+ * and PHY 1 is phy_0_peer.
+ * On dual complex E825C, device phy_0 points to PHY on a current
+ * complex and phy_0_peer to PHY on a different complex.
+ */
+ if ((!ice_is_dual(hw) && phy) ||
+ (ice_is_dual(hw) && phy != curr_phy))
+ return ice_sbq_dev_phy_0_peer;
+ else
+ return ice_sbq_dev_phy_0;
+}
+
+/**
+ * ice_cpi_write_phy - Write a CPI port register
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @addr: PHY register address
+ * @val: Value to write
+ *
+ * Return:
+ * * 0 on success
+ * * other error codes when failed to write to PHY
+ */
+static int ice_cpi_write_phy(struct ice_hw *hw, u8 phy, u32 addr, u32 val)
+{
+ struct ice_sbq_msg_input msg = {
+ .dest_dev = ice_cpi_get_dest_dev(hw, phy),
+ .opcode = ice_sbq_msg_wr_np,
+ .msg_addr_low = lower_16_bits(addr),
+ .msg_addr_high = upper_16_bits(addr),
+ .data = val
+ };
+ int err;
+
+ err = ice_sbq_rw_reg(hw, &msg, LIBIE_AQ_FLAG_RD);
+ if (err)
+ ice_debug(hw, ICE_DBG_PTP,
+ "Failed to write CPI msg to phy %d, err: %d\n",
+ phy, err);
+
+ return err;
+}
+
+/**
+ * ice_cpi_read_phy - Read a CPI port register
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @addr: PHY register address
+ * @val: storage for register value
+ *
+ * Return:
+ * * 0 on success
+ * * other error codes when failed to read from PHY
+ */
+static int ice_cpi_read_phy(struct ice_hw *hw, u8 phy, u32 addr, u32 *val)
+{
+ struct ice_sbq_msg_input msg = {
+ .dest_dev = ice_cpi_get_dest_dev(hw, phy),
+ .opcode = ice_sbq_msg_rd,
+ .msg_addr_low = lower_16_bits(addr),
+ .msg_addr_high = upper_16_bits(addr)
+ };
+ int err;
+
+ err = ice_sbq_rw_reg(hw, &msg, LIBIE_AQ_FLAG_RD);
+ if (err) {
+ ice_debug(hw, ICE_DBG_PTP,
+ "Failed to read CPI msg from phy %d, err: %d\n",
+ phy, err);
+ return err;
+ }
+
+ *val = msg.data;
+
+ return 0;
+}
+
+/**
+ * ice_cpi_wait_req0_ack0 - waits for CPI interface to be available
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ *
+ * This function checks if CPI interface is ready to use by CPI client.
+ * It's done by assuring LM.CMD.REQ and PHY.CMD.ACK bit in CPI
+ * interface registers to be 0.
+ *
+ * Return: 0 on success, negative on error
+ */
+static int ice_cpi_wait_req0_ack0(struct ice_hw *hw, int phy)
+{
+ u32 phy_val;
+ u32 lm_val;
+
+ for (int i = 0; i < CPI_RETRIES_COUNT; i++) {
+ int err;
+
+ /* check if another CPI Client is also accessing CPI */
+ err = ice_cpi_read_phy(hw, phy, CPI0_LM1_CMD_DATA, &lm_val);
+ if (err)
+ return err;
+ if (FIELD_GET(CPI_LM_CMD_REQ_M, lm_val))
+ goto retry;
+
+ /* check if PHY.ACK is deasserted */
+ err = ice_cpi_read_phy(hw, phy, CPI0_PHY1_CMD_DATA, &phy_val);
+ if (err)
+ return err;
+ if (!FIELD_GET(CPI_PHY_CMD_ACK_M, phy_val))
+ /* req0 and ack0 at this point - ready to go */
+ return 0;
+
+retry:
+ msleep(CPI_RETRIES_CADENCE_MS);
+ }
+
+ return -ETIMEDOUT;
+}
+
+/**
+ * ice_cpi_wait_ack - Waits for the PHY.ACK bit to be asserted/deasserted
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @asserted: desired state of PHY.ACK bit
+ * @data: pointer to the user data where PHY.data is stored
+ *
+ * This function checks if PHY.ACK bit is asserted or deasserted, depending
+ * on the phase of CPI handshake. If 'asserted' state is required, PHY command
+ * data is stored in the 'data' storage.
+ *
+ * Return: 0 on success, negative on error
+ */
+static int ice_cpi_wait_ack(struct ice_hw *hw, u8 phy, bool asserted,
+ u32 *data)
+{
+ u32 phy_val;
+
+ for (int i = 0; i < CPI_RETRIES_COUNT; i++) {
+ int err;
+
+ err = ice_cpi_read_phy(hw, phy, CPI0_PHY1_CMD_DATA, &phy_val);
+ if (err)
+ return err;
+ if (asserted && FIELD_GET(CPI_PHY_CMD_ERROR_M, phy_val))
+ return -EFAULT;
+ if (asserted && FIELD_GET(CPI_PHY_CMD_ACK_M, phy_val)) {
+ if (data)
+ *data = phy_val;
+ return 0;
+ }
+ if (!asserted && !FIELD_GET(CPI_PHY_CMD_ACK_M, phy_val))
+ return 0;
+
+ msleep(CPI_RETRIES_CADENCE_MS);
+ }
+
+ return -ETIMEDOUT;
+}
+
+#define ice_cpi_wait_ack0(hw, port) \
+ ice_cpi_wait_ack(hw, port, false, NULL)
+
+#define ice_cpi_wait_ack1(hw, port, data) \
+ ice_cpi_wait_ack(hw, port, true, data)
+
+/**
+ * ice_cpi_req0 - deasserts LM.REQ bit
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @data: the command data
+ *
+ * Return: 0 on success, negative on CPI write error
+ */
+static int ice_cpi_req0(struct ice_hw *hw, u8 phy, u32 data)
+{
+ data &= ~CPI_LM_CMD_REQ_M;
+
+ return ice_cpi_write_phy(hw, phy, CPI0_LM1_CMD_DATA, data);
+}
+
+/**
+ * ice_cpi_exec_cmd - writes command data to CPI interface
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @data: the command data
+ *
+ * Return: 0 on success, otherwise negative on error
+ */
+static int ice_cpi_exec_cmd(struct ice_hw *hw, int phy, u32 data)
+{
+ return ice_cpi_write_phy(hw, phy, CPI0_LM1_CMD_DATA, data);
+}
+
+/**
+ * ice_cpi_phy_lock - get per-PHY lock for CPI transaction serialization
+ * @hw: pointer to the HW struct
+ * @phy: PHY index
+ *
+ * Return: pointer to PHY mutex, or %NULL when context is unavailable.
+ */
+static struct mutex *ice_cpi_phy_lock(struct ice_hw *hw, u8 phy)
+{
+ struct ice_pf *pf = hw->back;
+
+ if (!pf || !pf->adapter || phy >= ICE_E825_MAX_PHYS)
+ return NULL;
+
+ return &pf->adapter->cpi_phy_lock[phy];
+}
+
+/**
+ * ice_cpi_exec - executes CPI command
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port the CPI action is taken on
+ * @cmd: pointer to the command struct to execute
+ * @resp: pointer to user allocated CPI response struct
+ *
+ * This function executes CPI request with respect to CPI handshake
+ * mechanism.
+ *
+ * Return: 0 on success, otherwise negative on error
+ */
+int ice_cpi_exec(struct ice_hw *hw, u8 phy,
+ const struct ice_cpi_cmd *cmd,
+ struct ice_cpi_resp *resp)
+{
+ struct mutex *cpi_lock; /* serializes CPI transactions per PHY */
+ u32 phy_cmd, lm_cmd = 0;
+ int err, err1 = 0;
+
+ if (!cmd || !resp)
+ return -EINVAL;
+
+ cpi_lock = ice_cpi_phy_lock(hw, phy);
+ if (!cpi_lock)
+ return -EINVAL;
+
+ mutex_lock(cpi_lock);
+
+ lm_cmd =
+ FIELD_PREP(CPI_LM_CMD_REQ_M, CPI_LM_CMD_REQ) |
+ FIELD_PREP(CPI_LM_CMD_GET_SET_M, cmd->set) |
+ FIELD_PREP(CPI_LM_CMD_OPCODE_M, cmd->opcode) |
+ FIELD_PREP(CPI_LM_CMD_PORTLANE_M, cmd->port) |
+ FIELD_PREP(CPI_LM_CMD_DATA_M, cmd->data);
+
+ /* 1. Try to acquire the bus, PHY ACK should be low before we begin */
+ err = ice_cpi_wait_req0_ack0(hw, phy);
+ if (err)
+ goto cpi_exec_exit;
+
+ /* 2. We start the CPI request */
+ err = ice_cpi_exec_cmd(hw, phy, lm_cmd);
+ if (err)
+ goto cpi_deassert;
+
+ /*
+ * 3. Wait for CPI confirmation, PHY ACK should be asserted and opcode
+ * echoed in the response
+ */
+ err = ice_cpi_wait_ack1(hw, phy, &phy_cmd);
+ if (err)
+ goto cpi_deassert;
+
+ if (FIELD_GET(CPI_LM_CMD_OPCODE_M, lm_cmd) !=
+ FIELD_GET(CPI_PHY_CMD_OPCODE_M, phy_cmd)) {
+ err = -EFAULT;
+ goto cpi_deassert;
+ }
+
+ resp->opcode = FIELD_GET(CPI_PHY_CMD_OPCODE_M, phy_cmd);
+ resp->data = FIELD_GET(CPI_PHY_CMD_DATA_M, phy_cmd);
+ resp->port = FIELD_GET(CPI_PHY_CMD_PORTLANE_M, phy_cmd);
+
+cpi_deassert:
+ /* 4. We deassert REQ */
+ err1 = ice_cpi_req0(hw, phy, lm_cmd);
+ if (err1)
+ goto cpi_exec_exit;
+
+ /* 5. PHY ACK should be deasserted in response */
+ err1 = ice_cpi_wait_ack0(hw, phy);
+
+cpi_exec_exit:
+ if (!err)
+ err = err1;
+
+ mutex_unlock(cpi_lock);
+
+ return err;
+}
+
+/**
+ * ice_cpi_set_cmd - execute CPI SET command
+ * @hw: pointer to the HW struct
+ * @opcode: CPI command opcode
+ * @phy: phy index CPI command is applied for
+ * @port_lane: ephy index CPI command is applied for
+ * @data: CPI opcode context specific data
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+static int ice_cpi_set_cmd(struct ice_hw *hw, u8 opcode, u8 phy, u8 port_lane,
+ u16 data)
+{
+ struct ice_cpi_resp cpi_resp = {0};
+ struct ice_cpi_cmd cpi_cmd = {
+ .opcode = opcode,
+ .set = true,
+ .port = port_lane,
+ .data = data,
+ };
+
+ return ice_cpi_exec(hw, phy, &cpi_cmd, &cpi_resp);
+}
+
+/**
+ * ice_cpi_ena_dis_clk_ref - enables/disables Tx reference clock on port
+ * @hw: pointer to the HW struct
+ * @phy: phy index of port for which Tx reference clock is enabled/disabled
+ * @clk: Tx reference clock to enable or disable
+ * @enable: bool value to enable or disable Tx reference clock
+ *
+ * This function executes CPI request to enable or disable specific
+ * Tx reference clock on given PHY.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int ice_cpi_ena_dis_clk_ref(struct ice_hw *hw, u8 phy,
+ enum ice_e825c_ref_clk clk, bool enable)
+{
+ u16 val;
+
+ val = FIELD_PREP(CPI_OPCODE_PHY_CLK_PHY_SEL_M, phy) |
+ FIELD_PREP(CPI_OPCODE_PHY_CLK_REF_CTRL_M,
+ enable ? CPI_OPCODE_PHY_CLK_ENABLE :
+ CPI_OPCODE_PHY_CLK_DISABLE) |
+ FIELD_PREP(CPI_OPCODE_PHY_CLK_REF_SEL_M, clk);
+
+ return ice_cpi_set_cmd(hw, CPI_OPCODE_PHY_CLK, phy, 0, val);
+}
+
projects / thirdparty / linux.git / commitdiff
