core.h

  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
 18struct device;
 19struct fw_card;
 20struct fw_device;
 21struct fw_iso_buffer;
 22struct fw_iso_context;
 23struct fw_iso_packet;
 24struct fw_node;
 25struct 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
 35extern __printf(2, 3)
 36void fw_err(const struct fw_card *card, const char *fmt, ...);
 37extern __printf(2, 3)
 38void 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
 58struct 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
124void fw_card_initialize(struct fw_card *card,
125		const struct fw_card_driver *driver, struct device *device);
126int fw_card_add(struct fw_card *card, u32 max_receive, u32 link_speed, u64 guid,
127		unsigned int supported_isoc_contexts);
128void fw_core_remove_card(struct fw_card *card);
129int fw_compute_block_crc(__be32 *block);
130void fw_schedule_bm_work(struct fw_card *card, unsigned long delay);
131
132/* -cdev */
133
134extern const struct file_operations fw_device_ops;
135
136void fw_device_cdev_update(struct fw_device *device);
137void fw_device_cdev_remove(struct fw_device *device);
138void fw_cdev_handle_phy_packet(struct fw_card *card, struct fw_packet *p);
139
140
141/* -device */
142
143extern struct rw_semaphore fw_device_rwsem;
144extern struct xarray fw_device_xa;
145extern int fw_cdev_major;
146
147static inline struct fw_device *fw_device_get(struct fw_device *device)
148{
149	get_device(&device->device);
150
151	return device;
152}
153
154static inline void fw_device_put(struct fw_device *device)
155{
156	put_device(&device->device);
157}
158
159struct fw_device *fw_device_get_by_devt(dev_t devt);
160int fw_device_set_broadcast_channel(struct device *dev, void *gen);
161void fw_node_event(struct fw_card *card, struct fw_node *node, int event);
162
163
164/* -iso */
165
166int fw_iso_buffer_alloc(struct fw_iso_buffer *buffer, int page_count);
167int fw_iso_buffer_map_dma(struct fw_iso_buffer *buffer, struct fw_card *card,
168			  enum dma_data_direction direction);
169
170static 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
181enum {
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
190struct 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
214static inline struct fw_node *fw_node_get(struct fw_node *node)
215{
216	kref_get(&node->kref);
217
218	return node;
219}
220
221static 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
228static inline void fw_node_put(struct fw_node *node)
229{
230	kref_put(&node->kref, release_node);
231}
232
233static inline struct fw_device *fw_node_get_device(struct fw_node *node)
234{
235	return node->device;
236}
237
238static inline void fw_node_set_device(struct fw_node *node, struct fw_device *device)
239{
240	node->device = device;
241}
242
243void 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);
245void 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 */
251static 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
261static inline bool tcode_is_read_request(unsigned int tcode)
262{
263	return (tcode & ~1u) == 4u;
264}
265
266static inline bool tcode_is_block_packet(unsigned int tcode)
267{
268	return (tcode & 1u) != 0u;
269}
270
271static 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
281void fw_core_handle_request(struct fw_card *card, struct fw_packet *request);
282void fw_core_handle_response(struct fw_card *card, struct fw_packet *packet);
283int fw_get_response_length(struct fw_request *request);
284void fw_fill_response(struct fw_packet *response, u32 *request_header,
285		      int rcode, void *payload, size_t length);
286
287void fw_request_get(struct fw_request *request);
288void fw_request_put(struct fw_request *request);
289
290void 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.
294static 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
301void fw_send_phy_config(struct fw_card *card,
302			int node_id, int generation, int gap_count);
303
304static inline bool is_ping_packet(u32 *data)
305{
306	return (data[0] & 0xc0ffffff) == 0 && ~data[0] == data[1];
307}
308
309static 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 */