xref: /openbmc/linux/drivers/thunderbolt/tb.h (revision ca55b2fe)
1 /*
2  * Thunderbolt Cactus Ridge driver - bus logic (NHI independent)
3  *
4  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
5  */
6 
7 #ifndef TB_H_
8 #define TB_H_
9 
10 #include <linux/pci.h>
11 
12 #include "tb_regs.h"
13 #include "ctl.h"
14 
15 /**
16  * struct tb_switch - a thunderbolt switch
17  */
18 struct tb_switch {
19 	struct tb_regs_switch_header config;
20 	struct tb_port *ports;
21 	struct tb *tb;
22 	u64 uid;
23 	int cap_plug_events; /* offset, zero if not found */
24 	bool is_unplugged; /* unplugged, will go away */
25 	u8 *drom;
26 };
27 
28 /**
29  * struct tb_port - a thunderbolt port, part of a tb_switch
30  */
31 struct tb_port {
32 	struct tb_regs_port_header config;
33 	struct tb_switch *sw;
34 	struct tb_port *remote; /* remote port, NULL if not connected */
35 	int cap_phy; /* offset, zero if not found */
36 	u8 port; /* port number on switch */
37 	bool disabled; /* disabled by eeprom */
38 	struct tb_port *dual_link_port;
39 	u8 link_nr:1;
40 };
41 
42 /**
43  * struct tb_path_hop - routing information for a tb_path
44  *
45  * Hop configuration is always done on the IN port of a switch.
46  * in_port and out_port have to be on the same switch. Packets arriving on
47  * in_port with "hop" = in_hop_index will get routed to through out_port. The
48  * next hop to take (on out_port->remote) is determined by next_hop_index.
49  *
50  * in_counter_index is the index of a counter (in TB_CFG_COUNTERS) on the in
51  * port.
52  */
53 struct tb_path_hop {
54 	struct tb_port *in_port;
55 	struct tb_port *out_port;
56 	int in_hop_index;
57 	int in_counter_index; /* write -1 to disable counters for this hop. */
58 	int next_hop_index;
59 };
60 
61 /**
62  * enum tb_path_port - path options mask
63  */
64 enum tb_path_port {
65 	TB_PATH_NONE = 0,
66 	TB_PATH_SOURCE = 1, /* activate on the first hop (out of src) */
67 	TB_PATH_INTERNAL = 2, /* activate on other hops (not the first/last) */
68 	TB_PATH_DESTINATION = 4, /* activate on the last hop (into dst) */
69 	TB_PATH_ALL = 7,
70 };
71 
72 /**
73  * struct tb_path - a unidirectional path between two ports
74  *
75  * A path consists of a number of hops (see tb_path_hop). To establish a PCIe
76  * tunnel two paths have to be created between the two PCIe ports.
77  *
78  */
79 struct tb_path {
80 	struct tb *tb;
81 	int nfc_credits; /* non flow controlled credits */
82 	enum tb_path_port ingress_shared_buffer;
83 	enum tb_path_port egress_shared_buffer;
84 	enum tb_path_port ingress_fc_enable;
85 	enum tb_path_port egress_fc_enable;
86 
87 	int priority:3;
88 	int weight:4;
89 	bool drop_packages;
90 	bool activated;
91 	struct tb_path_hop *hops;
92 	int path_length; /* number of hops */
93 };
94 
95 
96 /**
97  * struct tb - main thunderbolt bus structure
98  */
99 struct tb {
100 	struct mutex lock;	/*
101 				 * Big lock. Must be held when accessing cfg or
102 				 * any struct tb_switch / struct tb_port.
103 				 */
104 	struct tb_nhi *nhi;
105 	struct tb_ctl *ctl;
106 	struct workqueue_struct *wq; /* ordered workqueue for plug events */
107 	struct tb_switch *root_switch;
108 	struct list_head tunnel_list; /* list of active PCIe tunnels */
109 	bool hotplug_active; /*
110 			      * tb_handle_hotplug will stop progressing plug
111 			      * events and exit if this is not set (it needs to
112 			      * acquire the lock one more time). Used to drain
113 			      * wq after cfg has been paused.
114 			      */
115 
116 };
117 
118 /* helper functions & macros */
119 
120 /**
121  * tb_upstream_port() - return the upstream port of a switch
122  *
123  * Every switch has an upstream port (for the root switch it is the NHI).
124  *
125  * During switch alloc/init tb_upstream_port()->remote may be NULL, even for
126  * non root switches (on the NHI port remote is always NULL).
127  *
128  * Return: Returns the upstream port of the switch.
129  */
130 static inline struct tb_port *tb_upstream_port(struct tb_switch *sw)
131 {
132 	return &sw->ports[sw->config.upstream_port_number];
133 }
134 
135 static inline u64 tb_route(struct tb_switch *sw)
136 {
137 	return ((u64) sw->config.route_hi) << 32 | sw->config.route_lo;
138 }
139 
140 static inline int tb_sw_read(struct tb_switch *sw, void *buffer,
141 			     enum tb_cfg_space space, u32 offset, u32 length)
142 {
143 	return tb_cfg_read(sw->tb->ctl,
144 			   buffer,
145 			   tb_route(sw),
146 			   0,
147 			   space,
148 			   offset,
149 			   length);
150 }
151 
152 static inline int tb_sw_write(struct tb_switch *sw, void *buffer,
153 			      enum tb_cfg_space space, u32 offset, u32 length)
154 {
155 	return tb_cfg_write(sw->tb->ctl,
156 			    buffer,
157 			    tb_route(sw),
158 			    0,
159 			    space,
160 			    offset,
161 			    length);
162 }
163 
164 static inline int tb_port_read(struct tb_port *port, void *buffer,
165 			       enum tb_cfg_space space, u32 offset, u32 length)
166 {
167 	return tb_cfg_read(port->sw->tb->ctl,
168 			   buffer,
169 			   tb_route(port->sw),
170 			   port->port,
171 			   space,
172 			   offset,
173 			   length);
174 }
175 
176 static inline int tb_port_write(struct tb_port *port, void *buffer,
177 				enum tb_cfg_space space, u32 offset, u32 length)
178 {
179 	return tb_cfg_write(port->sw->tb->ctl,
180 			    buffer,
181 			    tb_route(port->sw),
182 			    port->port,
183 			    space,
184 			    offset,
185 			    length);
186 }
187 
188 #define tb_err(tb, fmt, arg...) dev_err(&(tb)->nhi->pdev->dev, fmt, ## arg)
189 #define tb_WARN(tb, fmt, arg...) dev_WARN(&(tb)->nhi->pdev->dev, fmt, ## arg)
190 #define tb_warn(tb, fmt, arg...) dev_warn(&(tb)->nhi->pdev->dev, fmt, ## arg)
191 #define tb_info(tb, fmt, arg...) dev_info(&(tb)->nhi->pdev->dev, fmt, ## arg)
192 
193 
194 #define __TB_SW_PRINT(level, sw, fmt, arg...)           \
195 	do {                                            \
196 		struct tb_switch *__sw = (sw);          \
197 		level(__sw->tb, "%llx: " fmt,           \
198 		      tb_route(__sw), ## arg);          \
199 	} while (0)
200 #define tb_sw_WARN(sw, fmt, arg...) __TB_SW_PRINT(tb_WARN, sw, fmt, ##arg)
201 #define tb_sw_warn(sw, fmt, arg...) __TB_SW_PRINT(tb_warn, sw, fmt, ##arg)
202 #define tb_sw_info(sw, fmt, arg...) __TB_SW_PRINT(tb_info, sw, fmt, ##arg)
203 
204 
205 #define __TB_PORT_PRINT(level, _port, fmt, arg...)                      \
206 	do {                                                            \
207 		struct tb_port *__port = (_port);                       \
208 		level(__port->sw->tb, "%llx:%x: " fmt,                  \
209 		      tb_route(__port->sw), __port->port, ## arg);      \
210 	} while (0)
211 #define tb_port_WARN(port, fmt, arg...) \
212 	__TB_PORT_PRINT(tb_WARN, port, fmt, ##arg)
213 #define tb_port_warn(port, fmt, arg...) \
214 	__TB_PORT_PRINT(tb_warn, port, fmt, ##arg)
215 #define tb_port_info(port, fmt, arg...) \
216 	__TB_PORT_PRINT(tb_info, port, fmt, ##arg)
217 
218 
219 struct tb *thunderbolt_alloc_and_start(struct tb_nhi *nhi);
220 void thunderbolt_shutdown_and_free(struct tb *tb);
221 void thunderbolt_suspend(struct tb *tb);
222 void thunderbolt_resume(struct tb *tb);
223 
224 struct tb_switch *tb_switch_alloc(struct tb *tb, u64 route);
225 void tb_switch_free(struct tb_switch *sw);
226 void tb_switch_suspend(struct tb_switch *sw);
227 int tb_switch_resume(struct tb_switch *sw);
228 int tb_switch_reset(struct tb *tb, u64 route);
229 void tb_sw_set_unpplugged(struct tb_switch *sw);
230 struct tb_switch *get_switch_at_route(struct tb_switch *sw, u64 route);
231 
232 int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged);
233 int tb_port_add_nfc_credits(struct tb_port *port, int credits);
234 int tb_port_clear_counter(struct tb_port *port, int counter);
235 
236 int tb_find_cap(struct tb_port *port, enum tb_cfg_space space, enum tb_cap cap);
237 
238 struct tb_path *tb_path_alloc(struct tb *tb, int num_hops);
239 void tb_path_free(struct tb_path *path);
240 int tb_path_activate(struct tb_path *path);
241 void tb_path_deactivate(struct tb_path *path);
242 bool tb_path_is_invalid(struct tb_path *path);
243 
244 int tb_drom_read(struct tb_switch *sw);
245 int tb_drom_read_uid_only(struct tb_switch *sw, u64 *uid);
246 
247 
248 static inline int tb_route_length(u64 route)
249 {
250 	return (fls64(route) + TB_ROUTE_SHIFT - 1) / TB_ROUTE_SHIFT;
251 }
252 
253 static inline bool tb_is_upstream_port(struct tb_port *port)
254 {
255 	return port == tb_upstream_port(port->sw);
256 }
257 
258 /**
259  * tb_downstream_route() - get route to downstream switch
260  *
261  * Port must not be the upstream port (otherwise a loop is created).
262  *
263  * Return: Returns a route to the switch behind @port.
264  */
265 static inline u64 tb_downstream_route(struct tb_port *port)
266 {
267 	return tb_route(port->sw)
268 	       | ((u64) port->port << (port->sw->config.depth * 8));
269 }
270 
271 #endif
272