xref: /linux/drivers/firewire/core.h (revision b0319c4642638bad4b36974055b1c0894b2c7aa9)
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 	// After returning the call, any function is no longer triggered to handle hardware event.
69 	void (*disable)(struct fw_card *card);
70 
71 	int (*read_phy_reg)(struct fw_card *card, int address);
72 	int (*update_phy_reg)(struct fw_card *card, int address,
73 			      int clear_bits, int set_bits);
74 
75 	/*
76 	 * Update the config rom for an enabled card.  This function
77 	 * should change the config rom that is presented on the bus
78 	 * and initiate a bus reset.
79 	 */
80 	int (*set_config_rom)(struct fw_card *card,
81 			      const __be32 *config_rom, size_t length);
82 
83 	void (*send_request)(struct fw_card *card, struct fw_packet *packet);
84 	void (*send_response)(struct fw_card *card, struct fw_packet *packet);
85 	/* Calling cancel is valid once a packet has been submitted. */
86 	int (*cancel_packet)(struct fw_card *card, struct fw_packet *packet);
87 
88 	/*
89 	 * Allow the specified node ID to do direct DMA out and in of
90 	 * host memory.  The card will disable this for all node when
91 	 * a bus reset happens, so driver need to re-enable this after
92 	 * bus reset.  Returns 0 on success, -ENODEV if the card
93 	 * doesn't support this, -ESTALE if the generation doesn't
94 	 * match.
95 	 */
96 	int (*enable_phys_dma)(struct fw_card *card,
97 			       int node_id, int generation);
98 
99 	u32 (*read_csr)(struct fw_card *card, int csr_offset);
100 	void (*write_csr)(struct fw_card *card, int csr_offset, u32 value);
101 
102 	struct fw_iso_context *
103 	(*allocate_iso_context)(struct fw_card *card,
104 				int type, int channel, size_t header_size);
105 	void (*free_iso_context)(struct fw_iso_context *ctx);
106 
107 	int (*start_iso)(struct fw_iso_context *ctx,
108 			 s32 cycle, u32 sync, u32 tags);
109 
110 	int (*set_iso_channels)(struct fw_iso_context *ctx, u64 *channels);
111 
112 	int (*queue_iso)(struct fw_iso_context *ctx,
113 			 struct fw_iso_packet *packet,
114 			 struct fw_iso_buffer *buffer,
115 			 unsigned long payload);
116 
117 	void (*flush_queue_iso)(struct fw_iso_context *ctx);
118 
119 	int (*flush_iso_completions)(struct fw_iso_context *ctx);
120 
121 	int (*stop_iso)(struct fw_iso_context *ctx);
122 };
123 
124 void fw_card_initialize(struct fw_card *card,
125 		const struct fw_card_driver *driver, struct device *device);
126 int fw_card_add(struct fw_card *card, u32 max_receive, u32 link_speed, u64 guid,
127 		unsigned int supported_isoc_contexts);
128 void fw_core_remove_card(struct fw_card *card);
129 int fw_compute_block_crc(__be32 *block);
130 void fw_schedule_bm_work(struct fw_card *card, unsigned long delay);
131 
132 /* -cdev */
133 
134 extern const struct file_operations fw_device_ops;
135 
136 void fw_device_cdev_update(struct fw_device *device);
137 void fw_device_cdev_remove(struct fw_device *device);
138 void fw_cdev_handle_phy_packet(struct fw_card *card, struct fw_packet *p);
139 
140 
141 /* -device */
142 
143 extern struct rw_semaphore fw_device_rwsem;
144 extern struct xarray fw_device_xa;
145 extern int fw_cdev_major;
146 
147 static inline struct fw_device *fw_device_get(struct fw_device *device)
148 {
149 	get_device(&device->device);
150 
151 	return device;
152 }
153 
154 static inline void fw_device_put(struct fw_device *device)
155 {
156 	put_device(&device->device);
157 }
158 
159 struct fw_device *fw_device_get_by_devt(dev_t devt);
160 int fw_device_set_broadcast_channel(struct device *dev, void *gen);
161 void fw_node_event(struct fw_card *card, struct fw_node *node, int event);
162 
163 
164 /* -iso */
165 
166 int fw_iso_buffer_alloc(struct fw_iso_buffer *buffer, int page_count);
167 int fw_iso_buffer_map_dma(struct fw_iso_buffer *buffer, struct fw_card *card,
168 			  enum dma_data_direction direction);
169 
170 static inline void fw_iso_context_init_work(struct fw_iso_context *ctx, work_func_t func)
171 {
172 	INIT_WORK(&ctx->work, func);
173 }
174 
175 
176 /* -topology */
177 
178 // The initial value of BUS_MANAGER_ID register, to express nothing registered.
179 #define BUS_MANAGER_ID_NOT_REGISTERED	0x3f
180 
181 enum {
182 	FW_NODE_CREATED,
183 	FW_NODE_UPDATED,
184 	FW_NODE_DESTROYED,
185 	FW_NODE_LINK_ON,
186 	FW_NODE_LINK_OFF,
187 	FW_NODE_INITIATED_RESET,
188 };
189 
190 struct fw_node {
191 	u16 node_id;
192 	u8 color;
193 	u8 port_count;
194 	u8 link_on:1;
195 	u8 initiated_reset:1;
196 	u8 b_path:1;
197 	u8 phy_speed:2;	/* As in the self ID packet. */
198 	u8 max_speed:2;	/* Minimum of all phy-speeds on the path from the
199 			 * local node to this node. */
200 	u8 max_depth:4;	/* Maximum depth to any leaf node */
201 	u8 max_hops:4;	/* Max hops in this sub tree */
202 
203 	struct kref kref;
204 
205 	/* For serializing node topology into a list. */
206 	struct list_head link;
207 
208 	// The device when already associated, else NULL.
209 	struct fw_device *device;
210 
211 	struct fw_node *ports[] __counted_by(port_count);
212 };
213 
214 static inline struct fw_node *fw_node_get(struct fw_node *node)
215 {
216 	kref_get(&node->kref);
217 
218 	return node;
219 }
220 
221 static void release_node(struct kref *kref)
222 {
223 	struct fw_node *node = container_of(kref, struct fw_node, kref);
224 
225 	kfree(node);
226 }
227 
228 static inline void fw_node_put(struct fw_node *node)
229 {
230 	kref_put(&node->kref, release_node);
231 }
232 
233 static inline struct fw_device *fw_node_get_device(struct fw_node *node)
234 {
235 	return node->device;
236 }
237 
238 static inline void fw_node_set_device(struct fw_node *node, struct fw_device *device)
239 {
240 	node->device = device;
241 }
242 
243 void fw_core_handle_bus_reset(struct fw_card *card, int node_id,
244 	int generation, int self_id_count, u32 *self_ids, bool bm_abdicate);
245 void fw_destroy_nodes(struct fw_card *card);
246 
247 /*
248  * Check whether new_generation is the immediate successor of old_generation.
249  * Take counter roll-over at 255 (as per OHCI) into account.
250  */
251 static inline bool is_next_generation(int new_generation, int old_generation)
252 {
253 	return (new_generation & 0xff) == ((old_generation + 1) & 0xff);
254 }
255 
256 
257 /* -transaction */
258 
259 #define TCODE_LINK_INTERNAL		0xe
260 
261 static inline bool tcode_is_read_request(unsigned int tcode)
262 {
263 	return (tcode & ~1u) == 4u;
264 }
265 
266 static inline bool tcode_is_block_packet(unsigned int tcode)
267 {
268 	return (tcode & 1u) != 0u;
269 }
270 
271 static inline bool tcode_is_link_internal(unsigned int tcode)
272 {
273 	return (tcode == TCODE_LINK_INTERNAL);
274 }
275 
276 #define LOCAL_BUS 0xffc0
277 
278 /* OHCI-1394's default upper bound for physical DMA: 4 GB */
279 #define FW_MAX_PHYSICAL_RANGE		(1ULL << 32)
280 
281 void fw_core_handle_request(struct fw_card *card, struct fw_packet *request);
282 void fw_core_handle_response(struct fw_card *card, struct fw_packet *packet);
283 int fw_get_response_length(struct fw_request *request);
284 void fw_fill_response(struct fw_packet *response, u32 *request_header,
285 		      int rcode, void *payload, size_t length);
286 
287 void fw_request_get(struct fw_request *request);
288 void fw_request_put(struct fw_request *request);
289 
290 void fw_cancel_pending_transactions(struct fw_card *card);
291 
292 // Convert the value of IEEE 1394 CYCLE_TIME register to the format of timeStamp field in
293 // descriptors of 1394 OHCI.
294 static inline u32 cycle_time_to_ohci_tstamp(u32 tstamp)
295 {
296 	return (tstamp & 0x0ffff000) >> 12;
297 }
298 
299 #define FW_PHY_CONFIG_NO_NODE_ID	-1
300 #define FW_PHY_CONFIG_CURRENT_GAP_COUNT	-1
301 void fw_send_phy_config(struct fw_card *card,
302 			int node_id, int generation, int gap_count);
303 
304 static inline bool is_ping_packet(u32 *data)
305 {
306 	return (data[0] & 0xc0ffffff) == 0 && ~data[0] == data[1];
307 }
308 
309 static inline bool is_in_fcp_region(u64 offset, size_t length)
310 {
311 	return offset >= (CSR_REGISTER_BASE | CSR_FCP_COMMAND) &&
312 		offset + length <= (CSR_REGISTER_BASE | CSR_FCP_END);
313 }
314 
315 #endif /* _FIREWIRE_CORE_H */
316