1 files changed, 409 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/ice/ice_gnss.c b/drivers/net/ethernet/intel/ice/ice_gnss.c
new file mode 100644
index 000000000..75c9de675
--- /dev/null
+++ b/drivers/net/ethernet/intel/ice/ice_gnss.c
@@ -0,0 +1,409 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2021-2022, Intel Corporation. */
+
+#include "ice.h"
+#include "ice_lib.h"
+
+/**
+ * ice_gnss_do_write - Write data to internal GNSS receiver
+ * @pf: board private structure
+ * @buf: command buffer
+ * @size: command buffer size
+ *
+ * Write UBX command data to the GNSS receiver
+ *
+ * Return:
+ * * number of bytes written - success
+ * * negative - error code
+ */
+static int
+ice_gnss_do_write(struct ice_pf *pf, const unsigned char *buf, unsigned int size)
+{
+	struct ice_aqc_link_topo_addr link_topo;
+	struct ice_hw *hw = &pf->hw;
+	unsigned int offset = 0;
+	int err = 0;
+
+	memset(&link_topo, 0, sizeof(struct ice_aqc_link_topo_addr));
+	link_topo.topo_params.index = ICE_E810T_GNSS_I2C_BUS;
+	link_topo.topo_params.node_type_ctx |=
+		FIELD_PREP(ICE_AQC_LINK_TOPO_NODE_CTX_M,
+			   ICE_AQC_LINK_TOPO_NODE_CTX_OVERRIDE);
+
+	/* It's not possible to write a single byte to u-blox.
+	 * Write all bytes in a loop until there are 6 or less bytes left. If
+	 * there are exactly 6 bytes left, the last write would be only a byte.
+	 * In this case, do 4+2 bytes writes instead of 5+1. Otherwise, do the
+	 * last 2 to 5 bytes write.
+	 */
+	while (size - offset > ICE_GNSS_UBX_WRITE_BYTES + 1) {
+		err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
+				       cpu_to_le16(buf[offset]),
+				       ICE_MAX_I2C_WRITE_BYTES,
+				       &buf[offset + 1], NULL);
+		if (err)
+			goto err_out;
+
+		offset += ICE_GNSS_UBX_WRITE_BYTES;
+	}
+
+	/* Single byte would be written. Write 4 bytes instead of 5. */
+	if (size - offset == ICE_GNSS_UBX_WRITE_BYTES + 1) {
+		err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
+				       cpu_to_le16(buf[offset]),
+				       ICE_MAX_I2C_WRITE_BYTES - 1,
+				       &buf[offset + 1], NULL);
+		if (err)
+			goto err_out;
+
+		offset += ICE_GNSS_UBX_WRITE_BYTES - 1;
+	}
+
+	/* Do the last write, 2 to 5 bytes. */
+	err = ice_aq_write_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
+			       cpu_to_le16(buf[offset]), size - offset - 1,
+			       &buf[offset + 1], NULL);
+	if (err)
+		goto err_out;
+
+	return size;
+
+err_out:
+	dev_err(ice_pf_to_dev(pf), "GNSS failed to write, offset=%u, size=%u, err=%d\n",
+		offset, size, err);
+
+	return err;
+}
+
+/**
+ * ice_gnss_read - Read data from internal GNSS module
+ * @work: GNSS read work structure
+ *
+ * Read the data from internal GNSS receiver, write it to gnss_dev.
+ */
+static void ice_gnss_read(struct kthread_work *work)
+{
+	struct gnss_serial *gnss = container_of(work, struct gnss_serial,
+						read_work.work);
+	unsigned long delay = ICE_GNSS_POLL_DATA_DELAY_TIME;
+	unsigned int i, bytes_read, data_len, count;
+	struct ice_aqc_link_topo_addr link_topo;
+	struct ice_pf *pf;
+	struct ice_hw *hw;
+	__be16 data_len_b;
+	char *buf = NULL;
+	u8 i2c_params;
+	int err = 0;
+
+	pf = gnss->back;
+	if (!pf || !test_bit(ICE_FLAG_GNSS, pf->flags))
+		return;
+
+	hw = &pf->hw;
+
+	memset(&link_topo, 0, sizeof(struct ice_aqc_link_topo_addr));
+	link_topo.topo_params.index = ICE_E810T_GNSS_I2C_BUS;
+	link_topo.topo_params.node_type_ctx |=
+		FIELD_PREP(ICE_AQC_LINK_TOPO_NODE_CTX_M,
+			   ICE_AQC_LINK_TOPO_NODE_CTX_OVERRIDE);
+
+	i2c_params = ICE_GNSS_UBX_DATA_LEN_WIDTH |
+		     ICE_AQC_I2C_USE_REPEATED_START;
+
+	err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
+			      cpu_to_le16(ICE_GNSS_UBX_DATA_LEN_H),
+			      i2c_params, (u8 *)&data_len_b, NULL);
+	if (err)
+		goto requeue;
+
+	data_len = be16_to_cpu(data_len_b);
+	if (data_len == 0 || data_len == U16_MAX)
+		goto requeue;
+
+	/* The u-blox has data_len bytes for us to read */
+
+	data_len = min_t(typeof(data_len), data_len, PAGE_SIZE);
+
+	buf = (char *)get_zeroed_page(GFP_KERNEL);
+	if (!buf) {
+		err = -ENOMEM;
+		goto requeue;
+	}
+
+	/* Read received data */
+	for (i = 0; i < data_len; i += bytes_read) {
+		unsigned int bytes_left = data_len - i;
+
+		bytes_read = min_t(typeof(bytes_left), bytes_left,
+				   ICE_MAX_I2C_DATA_SIZE);
+
+		err = ice_aq_read_i2c(hw, link_topo, ICE_GNSS_UBX_I2C_BUS_ADDR,
+				      cpu_to_le16(ICE_GNSS_UBX_EMPTY_DATA),
+				      bytes_read, &buf[i], NULL);
+		if (err)
+			goto free_buf;
+	}
+
+	count = gnss_insert_raw(pf->gnss_dev, buf, i);
+	if (count != i)
+		dev_warn(ice_pf_to_dev(pf),
+			 "gnss_insert_raw ret=%d size=%d\n",
+			 count, i);
+	delay = ICE_GNSS_TIMER_DELAY_TIME;
+free_buf:
+	free_page((unsigned long)buf);
+requeue:
+	kthread_queue_delayed_work(gnss->kworker, &gnss->read_work, delay);
+	if (err)
+		dev_dbg(ice_pf_to_dev(pf), "GNSS failed to read err=%d\n", err);
+}
+
+/**
+ * ice_gnss_struct_init - Initialize GNSS receiver
+ * @pf: Board private structure
+ *
+ * Initialize GNSS structures and workers.
+ *
+ * Return:
+ * * pointer to initialized gnss_serial struct - success
+ * * NULL - error
+ */
+static struct gnss_serial *ice_gnss_struct_init(struct ice_pf *pf)
+{
+	struct device *dev = ice_pf_to_dev(pf);
+	struct kthread_worker *kworker;
+	struct gnss_serial *gnss;
+
+	gnss = kzalloc(sizeof(*gnss), GFP_KERNEL);
+	if (!gnss)
+		return NULL;
+
+	gnss->back = pf;
+	pf->gnss_serial = gnss;
+
+	kthread_init_delayed_work(&gnss->read_work, ice_gnss_read);
+	kworker = kthread_create_worker(0, "ice-gnss-%s", dev_name(dev));
+	if (IS_ERR(kworker)) {
+		kfree(gnss);
+		return NULL;
+	}
+
+	gnss->kworker = kworker;
+
+	return gnss;
+}
+
+/**
+ * ice_gnss_open - Open GNSS device
+ * @gdev: pointer to the gnss device struct
+ *
+ * Open GNSS device and start filling the read buffer for consumer.
+ *
+ * Return:
+ * * 0 - success
+ * * negative - error code
+ */
+static int ice_gnss_open(struct gnss_device *gdev)
+{
+	struct ice_pf *pf = gnss_get_drvdata(gdev);
+	struct gnss_serial *gnss;
+
+	if (!pf)
+		return -EFAULT;
+
+	if (!test_bit(ICE_FLAG_GNSS, pf->flags))
+		return -EFAULT;
+
+	gnss = pf->gnss_serial;
+	if (!gnss)
+		return -ENODEV;
+
+	kthread_queue_delayed_work(gnss->kworker, &gnss->read_work, 0);
+
+	return 0;
+}
+
+/**
+ * ice_gnss_close - Close GNSS device
+ * @gdev: pointer to the gnss device struct
+ *
+ * Close GNSS device, cancel worker, stop filling the read buffer.
+ */
+static void ice_gnss_close(struct gnss_device *gdev)
+{
+	struct ice_pf *pf = gnss_get_drvdata(gdev);
+	struct gnss_serial *gnss;
+
+	if (!pf)
+		return;
+
+	gnss = pf->gnss_serial;
+	if (!gnss)
+		return;
+
+	kthread_cancel_delayed_work_sync(&gnss->read_work);
+}
+
+/**
+ * ice_gnss_write - Write to GNSS device
+ * @gdev: pointer to the gnss device struct
+ * @buf: pointer to the user data
+ * @count: size of the buffer to be sent to the GNSS device
+ *
+ * Return:
+ * * number of written bytes - success
+ * * negative - error code
+ */
+static int
+ice_gnss_write(struct gnss_device *gdev, const unsigned char *buf,
+	       size_t count)
+{
+	struct ice_pf *pf = gnss_get_drvdata(gdev);
+	struct gnss_serial *gnss;
+
+	/* We cannot write a single byte using our I2C implementation. */
+	if (count <= 1 || count > ICE_GNSS_TTY_WRITE_BUF)
+		return -EINVAL;
+
+	if (!pf)
+		return -EFAULT;
+
+	if (!test_bit(ICE_FLAG_GNSS, pf->flags))
+		return -EFAULT;
+
+	gnss = pf->gnss_serial;
+	if (!gnss)
+		return -ENODEV;
+
+	return ice_gnss_do_write(pf, buf, count);
+}
+
+static const struct gnss_operations ice_gnss_ops = {
+	.open = ice_gnss_open,
+	.close = ice_gnss_close,
+	.write_raw = ice_gnss_write,
+};
+
+/**
+ * ice_gnss_register - Register GNSS receiver
+ * @pf: Board private structure
+ *
+ * Allocate and register GNSS receiver in the Linux GNSS subsystem.
+ *
+ * Return:
+ * * 0 - success
+ * * negative - error code
+ */
+static int ice_gnss_register(struct ice_pf *pf)
+{
+	struct gnss_device *gdev;
+	int ret;
+
+	gdev = gnss_allocate_device(ice_pf_to_dev(pf));
+	if (!gdev) {
+		dev_err(ice_pf_to_dev(pf),
+			"gnss_allocate_device returns NULL\n");
+		return -ENOMEM;
+	}
+
+	gdev->ops = &ice_gnss_ops;
+	gdev->type = GNSS_TYPE_UBX;
+	gnss_set_drvdata(gdev, pf);
+	ret = gnss_register_device(gdev);
+	if (ret) {
+		dev_err(ice_pf_to_dev(pf), "gnss_register_device err=%d\n",
+			ret);
+		gnss_put_device(gdev);
+	} else {
+		pf->gnss_dev = gdev;
+	}
+
+	return ret;
+}
+
+/**
+ * ice_gnss_deregister - Deregister GNSS receiver
+ * @pf: Board private structure
+ *
+ * Deregister GNSS receiver from the Linux GNSS subsystem,
+ * release its resources.
+ */
+static void ice_gnss_deregister(struct ice_pf *pf)
+{
+	if (pf->gnss_dev) {
+		gnss_deregister_device(pf->gnss_dev);
+		gnss_put_device(pf->gnss_dev);
+		pf->gnss_dev = NULL;
+	}
+}
+
+/**
+ * ice_gnss_init - Initialize GNSS support
+ * @pf: Board private structure
+ */
+void ice_gnss_init(struct ice_pf *pf)
+{
+	int ret;
+
+	pf->gnss_serial = ice_gnss_struct_init(pf);
+	if (!pf->gnss_serial)
+		return;
+
+	ret = ice_gnss_register(pf);
+	if (!ret) {
+		set_bit(ICE_FLAG_GNSS, pf->flags);
+		dev_info(ice_pf_to_dev(pf), "GNSS init successful\n");
+	} else {
+		ice_gnss_exit(pf);
+		dev_err(ice_pf_to_dev(pf), "GNSS init failure\n");
+	}
+}
+
+/**
+ * ice_gnss_exit - Disable GNSS TTY support
+ * @pf: Board private structure
+ */
+void ice_gnss_exit(struct ice_pf *pf)
+{
+	ice_gnss_deregister(pf);
+	clear_bit(ICE_FLAG_GNSS, pf->flags);
+
+	if (pf->gnss_serial) {
+		struct gnss_serial *gnss = pf->gnss_serial;
+
+		kthread_cancel_delayed_work_sync(&gnss->read_work);
+		kthread_destroy_worker(gnss->kworker);
+		gnss->kworker = NULL;
+
+		kfree(gnss);
+		pf->gnss_serial = NULL;
+	}
+}
+
+/**
+ * ice_gnss_is_gps_present - Check if GPS HW is present
+ * @hw: pointer to HW struct
+ */
+bool ice_gnss_is_gps_present(struct ice_hw *hw)
+{
+	if (!hw->func_caps.ts_func_info.src_tmr_owned)
+		return false;
+
+#if IS_ENABLED(CONFIG_PTP_1588_CLOCK)
+	if (ice_is_e810t(hw)) {
+		int err;
+		u8 data;
+
+		err = ice_read_pca9575_reg_e810t(hw, ICE_PCA9575_P0_IN, &data);
+		if (err || !!(data & ICE_E810T_P0_GNSS_PRSNT_N))
+			return false;
+	} else {
+		return false;
+	}
+#else
+	if (!ice_is_e810t(hw))
+		return false;
+#endif /* IS_ENABLED(CONFIG_PTP_1588_CLOCK) */
+
+	return true;
+}