xref: /linux/drivers/firewire/core.h (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _FIREWIRE_CORE_H
3 #define _FIREWIRE_CORE_H
4 
5 #include <linux/compiler.h>
6 #include <linux/device.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/fs.h>
9 #include <linux/list.h>
10 #include <linux/xarray.h>
11 #include <linux/mm_types.h>
12 #include <linux/rwsem.h>
13 #include <linux/slab.h>
14 #include <linux/types.h>
15 
16 #include <linux/refcount.h>
17 
18 struct device;
19 struct fw_card;
20 struct fw_device;
21 struct fw_iso_buffer;
22 struct fw_iso_context;
23 struct fw_iso_packet;
24 struct fw_node;
25 struct fw_packet;
26 
27 
28 /* -card */
29 
30 // This is the arbitrary value we use to indicate a mismatched gap count.
31 #define GAP_COUNT_MISMATCHED	0
32 
33 #define isoc_cycles_to_jiffies(cycles) usecs_to_jiffies((u32)div_u64((u64)cycles * USEC_PER_SEC, 8000))
34 
35 extern __printf(2, 3)
36 void fw_err(const struct fw_card *card, const char *fmt, ...);
37 extern __printf(2, 3)
38 void fw_notice(const struct fw_card *card, const char *fmt, ...);
39 
40 /* bitfields within the PHY registers */
41 #define PHY_LINK_ACTIVE		0x80
42 #define PHY_CONTENDER		0x40
43 #define PHY_BUS_RESET		0x40
44 #define PHY_EXTENDED_REGISTERS	0xe0
45 #define PHY_BUS_SHORT_RESET	0x40
46 #define PHY_INT_STATUS_BITS	0x3c
47 #define PHY_ENABLE_ACCEL	0x02
48 #define PHY_ENABLE_MULTI	0x01
49 #define PHY_PAGE_SELECT		0xe0
50 
51 #define BANDWIDTH_AVAILABLE_INITIAL	4915
52 #define BROADCAST_CHANNEL_INITIAL	(1 << 31 | 31)
53 #define BROADCAST_CHANNEL_VALID		(1 << 30)
54 
55 #define CSR_STATE_BIT_CMSTR	(1 << 8)
56 #define CSR_STATE_BIT_ABDICATE	(1 << 10)
57 
58 struct fw_card_driver {
59 	/*
60 	 * Enable the given card with the given initial config rom.
61 	 * This function is expected to activate the card, and either
62 	 * enable the PHY or set the link_on bit and initiate a bus
63 	 * reset.
64 	 */
65 	int (*enable)(struct fw_card *card,
66 		      const __be32 *config_rom, size_t length);
67 
68 	int (*read_phy_reg)(struct fw_card *card, int address);
69 	int (*update_phy_reg)(struct fw_card *card, int address,
70 			      int clear_bits, int set_bits);
71 
72 	/*
73 	 * Update the config rom for an enabled card.  This function
74 	 * should change the config rom that is presented on the bus
75 	 * and initiate a bus reset.
76 	 */
77 	int (*set_config_rom)(struct fw_card *card,
78 			      const __be32 *config_rom, size_t length);
79 
80 	void (*send_request)(struct fw_card *card, struct fw_packet *packet);
81 	void (*send_response)(struct fw_card *card, struct fw_packet *packet);
82 	/* Calling cancel is valid once a packet has been submitted. */
83 	int (*cancel_packet)(struct fw_card *card, struct fw_packet *packet);
84 
85 	/*
86 	 * Allow the specified node ID to do direct DMA out and in of
87 	 * host memory.  The card will disable this for all node when
88 	 * a bus reset happens, so driver need to re-enable this after
89 	 * bus reset.  Returns 0 on success, -ENODEV if the card
90 	 * doesn't support this, -ESTALE if the generation doesn't
91 	 * match.
92 	 */
93 	int (*enable_phys_dma)(struct fw_card *card,
94 			       int node_id, int generation);
95 
96 	u32 (*read_csr)(struct fw_card *card, int csr_offset);
97 	void (*write_csr)(struct fw_card *card, int csr_offset, u32 value);
98 
99 	struct fw_iso_context *
100 	(*allocate_iso_context)(struct fw_card *card,
101 				int type, int channel, size_t header_size);
102 	void (*free_iso_context)(struct fw_iso_context *ctx);
103 
104 	int (*start_iso)(struct fw_iso_context *ctx,
105 			 s32 cycle, u32 sync, u32 tags);
106 
107 	int (*set_iso_channels)(struct fw_iso_context *ctx, u64 *channels);
108 
109 	int (*queue_iso)(struct fw_iso_context *ctx,
110 			 struct fw_iso_packet *packet,
111 			 struct fw_iso_buffer *buffer,
112 			 unsigned long payload);
113 
114 	void (*flush_queue_iso)(struct fw_iso_context *ctx);
115 
116 	int (*flush_iso_completions)(struct fw_iso_context *ctx);
117 
118 	int (*stop_iso)(struct fw_iso_context *ctx);
119 };
120 
121 void fw_card_initialize(struct fw_card *card,
122 		const struct fw_card_driver *driver, struct device *device);
123 int fw_card_add(struct fw_card *card, u32 max_receive, u32 link_speed, u64 guid,
124 		unsigned int supported_isoc_contexts);
125 void fw_core_remove_card(struct fw_card *card);
126 int fw_compute_block_crc(__be32 *block);
127 void fw_schedule_bm_work(struct fw_card *card, unsigned long delay);
128 
129 /* -cdev */
130 
131 extern const struct file_operations fw_device_ops;
132 
133 void fw_device_cdev_update(struct fw_device *device);
134 void fw_device_cdev_remove(struct fw_device *device);
135 void fw_cdev_handle_phy_packet(struct fw_card *card, struct fw_packet *p);
136 
137 
138 /* -device */
139 
140 extern struct rw_semaphore fw_device_rwsem;
141 extern struct xarray fw_device_xa;
142 extern int fw_cdev_major;
143 
144 static inline struct fw_device *fw_device_get(struct fw_device *device)
145 {
146 	get_device(&device->device);
147 
148 	return device;
149 }
150 
151 static inline void fw_device_put(struct fw_device *device)
152 {
153 	put_device(&device->device);
154 }
155 
156 struct fw_device *fw_device_get_by_devt(dev_t devt);
157 int fw_device_set_broadcast_channel(struct device *dev, void *gen);
158 void fw_node_event(struct fw_card *card, struct fw_node *node, int event);
159 
160 
161 /* -iso */
162 
163 int fw_iso_buffer_alloc(struct fw_iso_buffer *buffer, int page_count);
164 int fw_iso_buffer_map_dma(struct fw_iso_buffer *buffer, struct fw_card *card,
165 			  enum dma_data_direction direction);
166 
167 static inline void fw_iso_context_init_work(struct fw_iso_context *ctx, work_func_t func)
168 {
169 	INIT_WORK(&ctx->work, func);
170 }
171 
172 
173 /* -topology */
174 
175 // The initial value of BUS_MANAGER_ID register, to express nothing registered.
176 #define BUS_MANAGER_ID_NOT_REGISTERED	0x3f
177 
178 enum {
179 	FW_NODE_CREATED,
180 	FW_NODE_UPDATED,
181 	FW_NODE_DESTROYED,
182 	FW_NODE_LINK_ON,
183 	FW_NODE_LINK_OFF,
184 	FW_NODE_INITIATED_RESET,
185 };
186 
187 struct fw_node {
188 	u16 node_id;
189 	u8 color;
190 	u8 port_count;
191 	u8 link_on:1;
192 	u8 initiated_reset:1;
193 	u8 b_path:1;
194 	u8 phy_speed:2;	/* As in the self ID packet. */
195 	u8 max_speed:2;	/* Minimum of all phy-speeds on the path from the
196 			 * local node to this node. */
197 	u8 max_depth:4;	/* Maximum depth to any leaf node */
198 	u8 max_hops:4;	/* Max hops in this sub tree */
199 
200 	struct kref kref;
201 
202 	/* For serializing node topology into a list. */
203 	struct list_head link;
204 
205 	// The device when already associated, else NULL.
206 	struct fw_device *device;
207 
208 	struct fw_node *ports[] __counted_by(port_count);
209 };
210 
211 static inline struct fw_node *fw_node_get(struct fw_node *node)
212 {
213 	kref_get(&node->kref);
214 
215 	return node;
216 }
217 
218 static void release_node(struct kref *kref)
219 {
220 	struct fw_node *node = container_of(kref, struct fw_node, kref);
221 
222 	kfree(node);
223 }
224 
225 static inline void fw_node_put(struct fw_node *node)
226 {
227 	kref_put(&node->kref, release_node);
228 }
229 
230 static inline struct fw_device *fw_node_get_device(struct fw_node *node)
231 {
232 	return node->device;
233 }
234 
235 static inline void fw_node_set_device(struct fw_node *node, struct fw_device *device)
236 {
237 	node->device = device;
238 }
239 
240 void fw_core_handle_bus_reset(struct fw_card *card, int node_id,
241 	int generation, int self_id_count, u32 *self_ids, bool bm_abdicate);
242 void fw_destroy_nodes(struct fw_card *card);
243 
244 /*
245  * Check whether new_generation is the immediate successor of old_generation.
246  * Take counter roll-over at 255 (as per OHCI) into account.
247  */
248 static inline bool is_next_generation(int new_generation, int old_generation)
249 {
250 	return (new_generation & 0xff) == ((old_generation + 1) & 0xff);
251 }
252 
253 
254 /* -transaction */
255 
256 #define TCODE_LINK_INTERNAL		0xe
257 
258 static inline bool tcode_is_read_request(unsigned int tcode)
259 {
260 	return (tcode & ~1u) == 4u;
261 }
262 
263 static inline bool tcode_is_block_packet(unsigned int tcode)
264 {
265 	return (tcode & 1u) != 0u;
266 }
267 
268 static inline bool tcode_is_link_internal(unsigned int tcode)
269 {
270 	return (tcode == TCODE_LINK_INTERNAL);
271 }
272 
273 #define LOCAL_BUS 0xffc0
274 
275 /* OHCI-1394's default upper bound for physical DMA: 4 GB */
276 #define FW_MAX_PHYSICAL_RANGE		(1ULL << 32)
277 
278 void fw_core_handle_request(struct fw_card *card, struct fw_packet *request);
279 void fw_core_handle_response(struct fw_card *card, struct fw_packet *packet);
280 int fw_get_response_length(struct fw_request *request);
281 void fw_fill_response(struct fw_packet *response, u32 *request_header,
282 		      int rcode, void *payload, size_t length);
283 
284 void fw_request_get(struct fw_request *request);
285 void fw_request_put(struct fw_request *request);
286 
287 // Convert the value of IEEE 1394 CYCLE_TIME register to the format of timeStamp field in
288 // descriptors of 1394 OHCI.
289 static inline u32 cycle_time_to_ohci_tstamp(u32 tstamp)
290 {
291 	return (tstamp & 0x0ffff000) >> 12;
292 }
293 
294 #define FW_PHY_CONFIG_NO_NODE_ID	-1
295 #define FW_PHY_CONFIG_CURRENT_GAP_COUNT	-1
296 void fw_send_phy_config(struct fw_card *card,
297 			int node_id, int generation, int gap_count);
298 
299 static inline bool is_ping_packet(u32 *data)
300 {
301 	return (data[0] & 0xc0ffffff) == 0 && ~data[0] == data[1];
302 }
303 
304 static inline bool is_in_fcp_region(u64 offset, size_t length)
305 {
306 	return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
307 		offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
308 }
309 
310 #endif /* _FIREWIRE_CORE_H */
311