1 // SPDX-License-Identifier: (GPL-2.0 OR MIT) 2 /* Google virtual Ethernet (gve) driver 3 * 4 * Copyright (C) 2025 Google LLC 5 */ 6 7 #include "gve.h" 8 #include "gve_adminq.h" 9 10 /* Interval to schedule a nic timestamp calibration, 250ms. */ 11 #define GVE_NIC_TS_SYNC_INTERVAL_MS 250 12 13 /* Read the nic timestamp from hardware via the admin queue. */ 14 int gve_clock_nic_ts_read(struct gve_priv *priv) 15 { 16 u64 nic_raw; 17 int err; 18 19 err = gve_adminq_report_nic_ts(priv, priv->nic_ts_report_bus); 20 if (err) 21 return err; 22 23 nic_raw = be64_to_cpu(priv->nic_ts_report->nic_timestamp); 24 WRITE_ONCE(priv->last_sync_nic_counter, nic_raw); 25 26 return 0; 27 } 28 29 static int gve_ptp_gettimex64(struct ptp_clock_info *info, 30 struct timespec64 *ts, 31 struct ptp_system_timestamp *sts) 32 { 33 return -EOPNOTSUPP; 34 } 35 36 static int gve_ptp_settime64(struct ptp_clock_info *info, 37 const struct timespec64 *ts) 38 { 39 return -EOPNOTSUPP; 40 } 41 42 static long gve_ptp_do_aux_work(struct ptp_clock_info *info) 43 { 44 const struct gve_ptp *ptp = container_of(info, struct gve_ptp, info); 45 struct gve_priv *priv = ptp->priv; 46 int err; 47 48 if (gve_get_reset_in_progress(priv) || !gve_get_admin_queue_ok(priv)) 49 goto out; 50 51 err = gve_clock_nic_ts_read(priv); 52 if (err && net_ratelimit()) 53 dev_err(&priv->pdev->dev, 54 "%s read err %d\n", __func__, err); 55 56 out: 57 return msecs_to_jiffies(GVE_NIC_TS_SYNC_INTERVAL_MS); 58 } 59 60 static const struct ptp_clock_info gve_ptp_caps = { 61 .owner = THIS_MODULE, 62 .name = "gve clock", 63 .gettimex64 = gve_ptp_gettimex64, 64 .settime64 = gve_ptp_settime64, 65 .do_aux_work = gve_ptp_do_aux_work, 66 }; 67 68 static int gve_ptp_init(struct gve_priv *priv) 69 { 70 struct gve_ptp *ptp; 71 int err; 72 73 if (!priv->nic_timestamp_supported) { 74 dev_dbg(&priv->pdev->dev, "Device does not support PTP\n"); 75 return -EOPNOTSUPP; 76 } 77 78 priv->ptp = kzalloc(sizeof(*priv->ptp), GFP_KERNEL); 79 if (!priv->ptp) 80 return -ENOMEM; 81 82 ptp = priv->ptp; 83 ptp->info = gve_ptp_caps; 84 ptp->clock = ptp_clock_register(&ptp->info, &priv->pdev->dev); 85 86 if (IS_ERR(ptp->clock)) { 87 dev_err(&priv->pdev->dev, "PTP clock registration failed\n"); 88 err = PTR_ERR(ptp->clock); 89 goto free_ptp; 90 } 91 92 ptp->priv = priv; 93 return 0; 94 95 free_ptp: 96 kfree(ptp); 97 priv->ptp = NULL; 98 return err; 99 } 100 101 static void gve_ptp_release(struct gve_priv *priv) 102 { 103 struct gve_ptp *ptp = priv->ptp; 104 105 if (!ptp) 106 return; 107 108 if (ptp->clock) 109 ptp_clock_unregister(ptp->clock); 110 111 kfree(ptp); 112 priv->ptp = NULL; 113 } 114 115 int gve_init_clock(struct gve_priv *priv) 116 { 117 int err; 118 119 if (!priv->nic_timestamp_supported) 120 return 0; 121 122 err = gve_ptp_init(priv); 123 if (err) 124 return err; 125 126 priv->nic_ts_report = 127 dma_alloc_coherent(&priv->pdev->dev, 128 sizeof(struct gve_nic_ts_report), 129 &priv->nic_ts_report_bus, 130 GFP_KERNEL); 131 if (!priv->nic_ts_report) { 132 dev_err(&priv->pdev->dev, "%s dma alloc error\n", __func__); 133 err = -ENOMEM; 134 goto release_ptp; 135 } 136 137 return 0; 138 139 release_ptp: 140 gve_ptp_release(priv); 141 return err; 142 } 143 144 void gve_teardown_clock(struct gve_priv *priv) 145 { 146 gve_ptp_release(priv); 147 148 if (priv->nic_ts_report) { 149 dma_free_coherent(&priv->pdev->dev, 150 sizeof(struct gve_nic_ts_report), 151 priv->nic_ts_report, priv->nic_ts_report_bus); 152 priv->nic_ts_report = NULL; 153 } 154 } 155