1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
3  */
4 #ifndef _SJA1105_PTP_H
5 #define _SJA1105_PTP_H
6 
7 #include <linux/timer.h>
8 
9 #if IS_ENABLED(CONFIG_NET_DSA_SJA1105_PTP)
10 
11 /* Timestamps are in units of 8 ns clock ticks (equivalent to
12  * a fixed 125 MHz clock).
13  */
14 #define SJA1105_TICK_NS			8
15 
16 static inline s64 ns_to_sja1105_ticks(s64 ns)
17 {
18 	return ns / SJA1105_TICK_NS;
19 }
20 
21 static inline s64 sja1105_ticks_to_ns(s64 ticks)
22 {
23 	return ticks * SJA1105_TICK_NS;
24 }
25 
26 /* Calculate the first base_time in the future that satisfies this
27  * relationship:
28  *
29  * future_base_time = base_time + N x cycle_time >= now, or
30  *
31  *      now - base_time
32  * N >= ---------------
33  *         cycle_time
34  *
35  * Because N is an integer, the ceiling value of the above "a / b" ratio
36  * is in fact precisely the floor value of "(a + b - 1) / b", which is
37  * easier to calculate only having integer division tools.
38  */
39 static inline s64 future_base_time(s64 base_time, s64 cycle_time, s64 now)
40 {
41 	s64 a, b, n;
42 
43 	if (base_time >= now)
44 		return base_time;
45 
46 	a = now - base_time;
47 	b = cycle_time;
48 	n = div_s64(a + b - 1, b);
49 
50 	return base_time + n * cycle_time;
51 }
52 
53 /* This is not a preprocessor macro because the "ns" argument may or may not be
54  * s64 at caller side. This ensures it is properly type-cast before div_s64.
55  */
56 static inline s64 ns_to_sja1105_delta(s64 ns)
57 {
58 	return div_s64(ns, 200);
59 }
60 
61 static inline s64 sja1105_delta_to_ns(s64 delta)
62 {
63 	return delta * 200;
64 }
65 
66 struct sja1105_ptp_cmd {
67 	u64 startptpcp;		/* start toggling PTP_CLK pin */
68 	u64 stopptpcp;		/* stop toggling PTP_CLK pin */
69 	u64 ptpstrtsch;		/* start schedule */
70 	u64 ptpstopsch;		/* stop schedule */
71 	u64 resptp;		/* reset */
72 	u64 corrclk4ts;		/* use the corrected clock for timestamps */
73 	u64 ptpclkadd;		/* enum sja1105_ptp_clk_mode */
74 };
75 
76 struct sja1105_ptp_data {
77 	struct timer_list extts_timer;
78 	struct sk_buff_head skb_rxtstamp_queue;
79 	struct ptp_clock_info caps;
80 	struct ptp_clock *clock;
81 	struct sja1105_ptp_cmd cmd;
82 	/* Serializes all operations on the PTP hardware clock */
83 	struct mutex lock;
84 	bool extts_enabled;
85 	u64 ptpsyncts;
86 };
87 
88 int sja1105_ptp_clock_register(struct dsa_switch *ds);
89 
90 void sja1105_ptp_clock_unregister(struct dsa_switch *ds);
91 
92 void sja1105et_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
93 			       enum packing_op op);
94 
95 void sja1105pqrs_ptp_cmd_packing(u8 *buf, struct sja1105_ptp_cmd *cmd,
96 				 enum packing_op op);
97 
98 int sja1105_get_ts_info(struct dsa_switch *ds, int port,
99 			struct ethtool_ts_info *ts);
100 
101 void sja1105_ptp_txtstamp_skb(struct dsa_switch *ds, int slot,
102 			      struct sk_buff *clone);
103 
104 bool sja1105_port_rxtstamp(struct dsa_switch *ds, int port,
105 			   struct sk_buff *skb, unsigned int type);
106 
107 void sja1105_port_txtstamp(struct dsa_switch *ds, int port,
108 			   struct sk_buff *skb);
109 
110 int sja1105_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr);
111 
112 int sja1105_hwtstamp_set(struct dsa_switch *ds, int port, struct ifreq *ifr);
113 
114 int __sja1105_ptp_gettimex(struct dsa_switch *ds, u64 *ns,
115 			   struct ptp_system_timestamp *sts);
116 
117 int __sja1105_ptp_settime(struct dsa_switch *ds, u64 ns,
118 			  struct ptp_system_timestamp *ptp_sts);
119 
120 int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta);
121 
122 int sja1105_ptp_commit(struct dsa_switch *ds, struct sja1105_ptp_cmd *cmd,
123 		       sja1105_spi_rw_mode_t rw);
124 
125 #else
126 
127 struct sja1105_ptp_cmd;
128 
129 /* Structures cannot be empty in C. Bah!
130  * Keep the mutex as the only element, which is a bit more difficult to
131  * refactor out of sja1105_main.c anyway.
132  */
133 struct sja1105_ptp_data {
134 	struct mutex lock;
135 };
136 
137 static inline int sja1105_ptp_clock_register(struct dsa_switch *ds)
138 {
139 	return 0;
140 }
141 
142 static inline void sja1105_ptp_clock_unregister(struct dsa_switch *ds) { }
143 
144 static inline void sja1105_ptp_txtstamp_skb(struct dsa_switch *ds, int slot,
145 					    struct sk_buff *clone)
146 {
147 }
148 
149 static inline int __sja1105_ptp_gettimex(struct dsa_switch *ds, u64 *ns,
150 					 struct ptp_system_timestamp *sts)
151 {
152 	return 0;
153 }
154 
155 static inline int __sja1105_ptp_settime(struct dsa_switch *ds, u64 ns,
156 					struct ptp_system_timestamp *ptp_sts)
157 {
158 	return 0;
159 }
160 
161 static inline int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta)
162 {
163 	return 0;
164 }
165 
166 static inline int sja1105_ptp_commit(struct dsa_switch *ds,
167 				     struct sja1105_ptp_cmd *cmd,
168 				     sja1105_spi_rw_mode_t rw)
169 {
170 	return 0;
171 }
172 
173 #define sja1105et_ptp_cmd_packing NULL
174 
175 #define sja1105pqrs_ptp_cmd_packing NULL
176 
177 #define sja1105_get_ts_info NULL
178 
179 #define sja1105_port_rxtstamp NULL
180 
181 #define sja1105_port_txtstamp NULL
182 
183 #define sja1105_hwtstamp_get NULL
184 
185 #define sja1105_hwtstamp_set NULL
186 
187 #endif /* IS_ENABLED(CONFIG_NET_DSA_SJA1105_PTP) */
188 
189 #endif /* _SJA1105_PTP_H */
190