1 // SPDX-License-Identifier: GPL-2.0-only
2 /*******************************************************************************
3 PTP 1588 clock using the STMMAC.
4
5 Copyright (C) 2013 Vayavya Labs Pvt Ltd
6
7
8 Author: Rayagond Kokatanur <rayagond@vayavyalabs.com>
9 *******************************************************************************/
10 #include "stmmac.h"
11 #include "stmmac_ptp.h"
12
13 /**
14 * stmmac_adjust_freq
15 *
16 * @ptp: pointer to ptp_clock_info structure
17 * @ppb: desired period change in parts ber billion
18 *
19 * Description: this function will adjust the frequency of hardware clock.
20 */
stmmac_adjust_freq(struct ptp_clock_info * ptp,s32 ppb)21 static int stmmac_adjust_freq(struct ptp_clock_info *ptp, s32 ppb)
22 {
23 struct stmmac_priv *priv =
24 container_of(ptp, struct stmmac_priv, ptp_clock_ops);
25 unsigned long flags;
26 u32 diff, addend;
27 int neg_adj = 0;
28 u64 adj;
29
30 if (ppb < 0) {
31 neg_adj = 1;
32 ppb = -ppb;
33 }
34
35 addend = priv->default_addend;
36 adj = addend;
37 adj *= ppb;
38 diff = div_u64(adj, 1000000000ULL);
39 addend = neg_adj ? (addend - diff) : (addend + diff);
40
41 spin_lock_irqsave(&priv->ptp_lock, flags);
42 stmmac_config_addend(priv, priv->ptpaddr, addend);
43 spin_unlock_irqrestore(&priv->ptp_lock, flags);
44
45 return 0;
46 }
47
48 /**
49 * stmmac_adjust_time
50 *
51 * @ptp: pointer to ptp_clock_info structure
52 * @delta: desired change in nanoseconds
53 *
54 * Description: this function will shift/adjust the hardware clock time.
55 */
stmmac_adjust_time(struct ptp_clock_info * ptp,s64 delta)56 static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
57 {
58 struct stmmac_priv *priv =
59 container_of(ptp, struct stmmac_priv, ptp_clock_ops);
60 unsigned long flags;
61 u32 sec, nsec;
62 u32 quotient, reminder;
63 int neg_adj = 0;
64 bool xmac;
65
66 xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
67
68 if (delta < 0) {
69 neg_adj = 1;
70 delta = -delta;
71 }
72
73 quotient = div_u64_rem(delta, 1000000000ULL, &reminder);
74 sec = quotient;
75 nsec = reminder;
76
77 spin_lock_irqsave(&priv->ptp_lock, flags);
78 stmmac_adjust_systime(priv, priv->ptpaddr, sec, nsec, neg_adj, xmac);
79 spin_unlock_irqrestore(&priv->ptp_lock, flags);
80
81 return 0;
82 }
83
84 /**
85 * stmmac_get_time
86 *
87 * @ptp: pointer to ptp_clock_info structure
88 * @ts: pointer to hold time/result
89 *
90 * Description: this function will read the current time from the
91 * hardware clock and store it in @ts.
92 */
stmmac_get_time(struct ptp_clock_info * ptp,struct timespec64 * ts)93 static int stmmac_get_time(struct ptp_clock_info *ptp, struct timespec64 *ts)
94 {
95 struct stmmac_priv *priv =
96 container_of(ptp, struct stmmac_priv, ptp_clock_ops);
97 unsigned long flags;
98 u64 ns = 0;
99
100 spin_lock_irqsave(&priv->ptp_lock, flags);
101 stmmac_get_systime(priv, priv->ptpaddr, &ns);
102 spin_unlock_irqrestore(&priv->ptp_lock, flags);
103
104 *ts = ns_to_timespec64(ns);
105
106 return 0;
107 }
108
109 /**
110 * stmmac_set_time
111 *
112 * @ptp: pointer to ptp_clock_info structure
113 * @ts: time value to set
114 *
115 * Description: this function will set the current time on the
116 * hardware clock.
117 */
stmmac_set_time(struct ptp_clock_info * ptp,const struct timespec64 * ts)118 static int stmmac_set_time(struct ptp_clock_info *ptp,
119 const struct timespec64 *ts)
120 {
121 struct stmmac_priv *priv =
122 container_of(ptp, struct stmmac_priv, ptp_clock_ops);
123 unsigned long flags;
124
125 spin_lock_irqsave(&priv->ptp_lock, flags);
126 stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec);
127 spin_unlock_irqrestore(&priv->ptp_lock, flags);
128
129 return 0;
130 }
131
stmmac_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)132 static int stmmac_enable(struct ptp_clock_info *ptp,
133 struct ptp_clock_request *rq, int on)
134 {
135 struct stmmac_priv *priv =
136 container_of(ptp, struct stmmac_priv, ptp_clock_ops);
137 struct stmmac_pps_cfg *cfg;
138 int ret = -EOPNOTSUPP;
139 unsigned long flags;
140
141 switch (rq->type) {
142 case PTP_CLK_REQ_PEROUT:
143 /* Reject requests with unsupported flags */
144 if (rq->perout.flags)
145 return -EOPNOTSUPP;
146
147 cfg = &priv->pps[rq->perout.index];
148
149 cfg->start.tv_sec = rq->perout.start.sec;
150 cfg->start.tv_nsec = rq->perout.start.nsec;
151 cfg->period.tv_sec = rq->perout.period.sec;
152 cfg->period.tv_nsec = rq->perout.period.nsec;
153
154 spin_lock_irqsave(&priv->ptp_lock, flags);
155 ret = stmmac_flex_pps_config(priv, priv->ioaddr,
156 rq->perout.index, cfg, on,
157 priv->sub_second_inc,
158 priv->systime_flags);
159 spin_unlock_irqrestore(&priv->ptp_lock, flags);
160 break;
161 default:
162 break;
163 }
164
165 return ret;
166 }
167
168 /* structure describing a PTP hardware clock */
169 static struct ptp_clock_info stmmac_ptp_clock_ops = {
170 .owner = THIS_MODULE,
171 .name = "stmmac ptp",
172 .max_adj = 62500000,
173 .n_alarm = 0,
174 .n_ext_ts = 0,
175 .n_per_out = 0, /* will be overwritten in stmmac_ptp_register */
176 .n_pins = 0,
177 .pps = 0,
178 .adjfreq = stmmac_adjust_freq,
179 .adjtime = stmmac_adjust_time,
180 .gettime64 = stmmac_get_time,
181 .settime64 = stmmac_set_time,
182 .enable = stmmac_enable,
183 };
184
185 /**
186 * stmmac_ptp_register
187 * @priv: driver private structure
188 * Description: this function will register the ptp clock driver
189 * to kernel. It also does some house keeping work.
190 */
stmmac_ptp_register(struct stmmac_priv * priv)191 void stmmac_ptp_register(struct stmmac_priv *priv)
192 {
193 int i;
194
195 for (i = 0; i < priv->dma_cap.pps_out_num; i++) {
196 if (i >= STMMAC_PPS_MAX)
197 break;
198 priv->pps[i].available = true;
199 }
200
201 if (priv->plat->ptp_max_adj)
202 stmmac_ptp_clock_ops.max_adj = priv->plat->ptp_max_adj;
203
204 stmmac_ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num;
205
206 spin_lock_init(&priv->ptp_lock);
207 priv->ptp_clock_ops = stmmac_ptp_clock_ops;
208
209 priv->ptp_clock = ptp_clock_register(&priv->ptp_clock_ops,
210 priv->device);
211 if (IS_ERR(priv->ptp_clock)) {
212 netdev_err(priv->dev, "ptp_clock_register failed\n");
213 priv->ptp_clock = NULL;
214 } else if (priv->ptp_clock)
215 netdev_info(priv->dev, "registered PTP clock\n");
216 }
217
218 /**
219 * stmmac_ptp_unregister
220 * @priv: driver private structure
221 * Description: this function will remove/unregister the ptp clock driver
222 * from the kernel.
223 */
stmmac_ptp_unregister(struct stmmac_priv * priv)224 void stmmac_ptp_unregister(struct stmmac_priv *priv)
225 {
226 if (priv->ptp_clock) {
227 ptp_clock_unregister(priv->ptp_clock);
228 priv->ptp_clock = NULL;
229 pr_debug("Removed PTP HW clock successfully on %s\n",
230 priv->dev->name);
231 }
232 }
233
