1 /*
2  * Industry-pack bus.
3  *
4  * Copyright (C) 2011-2012 CERN (www.cern.ch)
5  * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; version 2 of the License.
10  */
11 
12 #include <linux/mod_devicetable.h>
13 #include <linux/device.h>
14 #include <linux/interrupt.h>
15 
16 #define IPACK_IDPROM_OFFSET_I			0x01
17 #define IPACK_IDPROM_OFFSET_P			0x03
18 #define IPACK_IDPROM_OFFSET_A			0x05
19 #define IPACK_IDPROM_OFFSET_C			0x07
20 #define IPACK_IDPROM_OFFSET_MANUFACTURER_ID	0x09
21 #define IPACK_IDPROM_OFFSET_MODEL		0x0B
22 #define IPACK_IDPROM_OFFSET_REVISION		0x0D
23 #define IPACK_IDPROM_OFFSET_RESERVED		0x0F
24 #define IPACK_IDPROM_OFFSET_DRIVER_ID_L		0x11
25 #define IPACK_IDPROM_OFFSET_DRIVER_ID_H		0x13
26 #define IPACK_IDPROM_OFFSET_NUM_BYTES		0x15
27 #define IPACK_IDPROM_OFFSET_CRC			0x17
28 
29 /*
30  * IndustryPack Fromat, Vendor and Device IDs.
31  */
32 
33 /* ID section format versions */
34 #define IPACK_ID_VERSION_INVALID	0x00
35 #define IPACK_ID_VERSION_1		0x01
36 #define IPACK_ID_VERSION_2		0x02
37 
38 /* Vendors and devices. Sort key: vendor first, device next. */
39 #define IPACK1_VENDOR_ID_RESERVED1	0x00
40 #define IPACK1_VENDOR_ID_RESERVED2	0xFF
41 #define IPACK1_VENDOR_ID_UNREGISTRED01	0x01
42 #define IPACK1_VENDOR_ID_UNREGISTRED02	0x02
43 #define IPACK1_VENDOR_ID_UNREGISTRED03	0x03
44 #define IPACK1_VENDOR_ID_UNREGISTRED04	0x04
45 #define IPACK1_VENDOR_ID_UNREGISTRED05	0x05
46 #define IPACK1_VENDOR_ID_UNREGISTRED06	0x06
47 #define IPACK1_VENDOR_ID_UNREGISTRED07	0x07
48 #define IPACK1_VENDOR_ID_UNREGISTRED08	0x08
49 #define IPACK1_VENDOR_ID_UNREGISTRED09	0x09
50 #define IPACK1_VENDOR_ID_UNREGISTRED10	0x0A
51 #define IPACK1_VENDOR_ID_UNREGISTRED11	0x0B
52 #define IPACK1_VENDOR_ID_UNREGISTRED12	0x0C
53 #define IPACK1_VENDOR_ID_UNREGISTRED13	0x0D
54 #define IPACK1_VENDOR_ID_UNREGISTRED14	0x0E
55 #define IPACK1_VENDOR_ID_UNREGISTRED15	0x0F
56 
57 #define IPACK1_VENDOR_ID_SBS            0xF0
58 #define IPACK1_DEVICE_ID_SBS_OCTAL_232  0x22
59 #define IPACK1_DEVICE_ID_SBS_OCTAL_422  0x2A
60 #define IPACK1_DEVICE_ID_SBS_OCTAL_485  0x48
61 
62 struct ipack_bus_ops;
63 struct ipack_driver;
64 
65 enum ipack_space {
66 	IPACK_IO_SPACE    = 0,
67 	IPACK_ID_SPACE,
68 	IPACK_INT_SPACE,
69 	IPACK_MEM8_SPACE,
70 	IPACK_MEM16_SPACE,
71 	/* Dummy for counting the number of entries.  Must remain the last
72 	 * entry */
73 	IPACK_SPACE_COUNT,
74 };
75 
76 /**
77  */
78 struct ipack_region {
79 	phys_addr_t start;
80 	size_t      size;
81 };
82 
83 /**
84  *	struct ipack_device
85  *
86  *	@slot: Slot where the device is plugged in the carrier board
87  *	@bus: ipack_bus_device where the device is plugged to.
88  *	@id_space: Virtual address to ID space.
89  *	@io_space: Virtual address to IO space.
90  *	@mem_space: Virtual address to MEM space.
91  *	@dev: device in kernel representation.
92  *
93  * Warning: Direct access to mapped memory is possible but the endianness
94  * is not the same with PCI carrier or VME carrier. The endianness is managed
95  * by the carrier board throught bus->ops.
96  */
97 struct ipack_device {
98 	unsigned int slot;
99 	struct ipack_bus_device *bus;
100 	struct device dev;
101 	void (*release) (struct ipack_device *dev);
102 	struct ipack_region      region[IPACK_SPACE_COUNT];
103 	u8                      *id;
104 	size_t			 id_avail;
105 	u32			 id_vendor;
106 	u32			 id_device;
107 	u8			 id_format;
108 	unsigned int		 id_crc_correct:1;
109 	unsigned int		 speed_8mhz:1;
110 	unsigned int		 speed_32mhz:1;
111 };
112 
113 /**
114  * struct ipack_driver_ops -- Callbacks to IPack device driver
115  *
116  * @probe:  Probe function
117  * @remove: Prepare imminent removal of the device.  Services provided by the
118  *          device should be revoked.
119  */
120 
121 struct ipack_driver_ops {
122 	int (*probe) (struct ipack_device *dev);
123 	void (*remove) (struct ipack_device *dev);
124 };
125 
126 /**
127  * struct ipack_driver -- Specific data to each ipack device driver
128  *
129  * @driver: Device driver kernel representation
130  * @ops:    Callbacks provided by the IPack device driver
131  */
132 struct ipack_driver {
133 	struct device_driver driver;
134 	const struct ipack_device_id *id_table;
135 	const struct ipack_driver_ops *ops;
136 };
137 
138 /**
139  *	struct ipack_bus_ops - available operations on a bridge module
140  *
141  *	@map_space: map IP address space
142  *	@unmap_space: unmap IP address space
143  *	@request_irq: request IRQ
144  *	@free_irq: free IRQ
145  *	@get_clockrate: Returns the clockrate the carrier is currently
146  *		communicating with the device at.
147  *	@set_clockrate: Sets the clock-rate for carrier / module communication.
148  *		Should return -EINVAL if the requested speed is not supported.
149  *	@get_error: Returns the error state for the slot the device is attached
150  *		to.
151  *	@get_timeout: Returns 1 if the communication with the device has
152  *		previously timed out.
153  *	@reset_timeout: Resets the state returned by get_timeout.
154  */
155 struct ipack_bus_ops {
156 	int (*request_irq) (struct ipack_device *dev,
157 			    irqreturn_t (*handler)(void *), void *arg);
158 	int (*free_irq) (struct ipack_device *dev);
159 	int (*get_clockrate) (struct ipack_device *dev);
160 	int (*set_clockrate) (struct ipack_device *dev, int mherz);
161 	int (*get_error) (struct ipack_device *dev);
162 	int (*get_timeout) (struct ipack_device *dev);
163 	int (*reset_timeout) (struct ipack_device *dev);
164 };
165 
166 /**
167  *	struct ipack_bus_device
168  *
169  *	@dev: pointer to carrier device
170  *	@slots: number of slots available
171  *	@bus_nr: ipack bus number
172  *	@ops: bus operations for the mezzanine drivers
173  */
174 struct ipack_bus_device {
175 	struct module *owner;
176 	struct device *parent;
177 	int slots;
178 	int bus_nr;
179 	const struct ipack_bus_ops *ops;
180 };
181 
182 /**
183  *	ipack_bus_register -- register a new ipack bus
184  *
185  * @parent: pointer to the parent device, if any.
186  * @slots: number of slots available in the bus device.
187  * @ops: bus operations for the mezzanine drivers.
188  *
189  * The carrier board device should call this function to register itself as
190  * available bus device in ipack.
191  */
192 struct ipack_bus_device *ipack_bus_register(struct device *parent, int slots,
193 					    const struct ipack_bus_ops *ops,
194 					    struct module *owner);
195 
196 /**
197  *	ipack_bus_unregister -- unregister an ipack bus
198  */
199 int ipack_bus_unregister(struct ipack_bus_device *bus);
200 
201 /**
202  * ipack_driver_register -- Register a new ipack device driver
203  *
204  * Called by a ipack driver to register itself as a driver
205  * that can manage ipack devices.
206  */
207 int ipack_driver_register(struct ipack_driver *edrv, struct module *owner,
208 			  const char *name);
209 void ipack_driver_unregister(struct ipack_driver *edrv);
210 
211 /**
212  *	ipack_device_init -- initialize an IPack device
213  * @dev: the new device to initialize.
214  *
215  * Initialize a new IPack device ("module" in IndustryPack jargon). The call
216  * is done by the carrier driver.  The carrier should populate the fields
217  * bus and slot as well as the region array of @dev prior to calling this
218  * function.  The rest of the fields will be allocated and populated
219  * during initalization.
220  *
221  * Return zero on success or error code on failure.
222  *
223  * NOTE: _Never_ directly free @dev after calling this function, even
224  * if it returned an error! Always use ipack_put_device() to give up the
225  * reference initialized in this function instead.
226  */
227 int ipack_device_init(struct ipack_device *dev);
228 
229 /**
230  *	ipack_device_add -- Add an IPack device
231  * @dev: the new device to add.
232  *
233  * Add a new IPack device. The call is done by the carrier driver
234  * after calling ipack_device_init().
235  *
236  * Return zero on success or error code on failure.
237  *
238  * NOTE: _Never_ directly free @dev after calling this function, even
239  * if it returned an error! Always use ipack_put_device() to give up the
240  * reference initialized in this function instead.
241  */
242 int ipack_device_add(struct ipack_device *dev);
243 void ipack_device_del(struct ipack_device *dev);
244 
245 void ipack_get_device(struct ipack_device *dev);
246 void ipack_put_device(struct ipack_device *dev);
247 
248 /**
249  * DEFINE_IPACK_DEVICE_TABLE - macro used to describe a IndustryPack table
250  * @_table: device table name
251  *
252  * This macro is used to create a struct ipack_device_id array (a device table)
253  * in a generic manner.
254  */
255 #define DEFINE_IPACK_DEVICE_TABLE(_table) \
256 	const struct ipack_device_id _table[]
257 /**
258  * IPACK_DEVICE - macro used to describe a specific IndustryPack device
259  * @_format: the format version (currently either 1 or 2, 8 bit value)
260  * @vend:    the 8 or 24 bit IndustryPack Vendor ID
261  * @dev:     the 8 or 16  bit IndustryPack Device ID
262  *
263  * This macro is used to create a struct ipack_device_id that matches a specific
264  * device.
265  */
266 #define IPACK_DEVICE(_format, vend, dev) \
267 	 .format = (_format), \
268 	 .vendor = (vend), \
269 	 .device = (dev)
270 
271 /**
272  * ipack_get_carrier - it increase the carrier ref. counter of
273  *                     the carrier module
274  * @dev: mezzanine device which wants to get the carrier
275  */
ipack_get_carrier(struct ipack_device * dev)276 static inline int ipack_get_carrier(struct ipack_device *dev)
277 {
278 	return try_module_get(dev->bus->owner);
279 }
280 
281 /**
282  * ipack_get_carrier - it decrease the carrier ref. counter of
283  *                     the carrier module
284  * @dev: mezzanine device which wants to get the carrier
285  */
ipack_put_carrier(struct ipack_device * dev)286 static inline void ipack_put_carrier(struct ipack_device *dev)
287 {
288 	module_put(dev->bus->owner);
289 }
290