1 /*****************************************************************************
2  *
3  *     Author: Xilinx, Inc.
4  *
5  *     This program is free software; you can redistribute it and/or modify it
6  *     under the terms of the GNU General Public License as published by the
7  *     Free Software Foundation; either version 2 of the License, or (at your
8  *     option) any later version.
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10  *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
11  *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
12  *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
13  *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
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15  *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
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22  *     FOR A PARTICULAR PURPOSE.
23  *
24  *     Xilinx products are not intended for use in life support appliances,
25  *     devices, or systems. Use in such applications is expressly prohibited.
26  *
27  *     (c) Copyright 2003-2008 Xilinx Inc.
28  *     All rights reserved.
29  *
30  *     You should have received a copy of the GNU General Public License along
31  *     with this program; if not, write to the Free Software Foundation, Inc.,
32  *     675 Mass Ave, Cambridge, MA 02139, USA.
33  *
34  *****************************************************************************/
35 
36 #include "buffer_icap.h"
37 
38 /* Indicates how many bytes will fit in a buffer. (1 BRAM) */
39 #define XHI_MAX_BUFFER_BYTES        2048
40 #define XHI_MAX_BUFFER_INTS         (XHI_MAX_BUFFER_BYTES >> 2)
41 
42 /* File access and error constants */
43 #define XHI_DEVICE_READ_ERROR       -1
44 #define XHI_DEVICE_WRITE_ERROR      -2
45 #define XHI_BUFFER_OVERFLOW_ERROR   -3
46 
47 #define XHI_DEVICE_READ             0x1
48 #define XHI_DEVICE_WRITE            0x0
49 
50 /* Constants for checking transfer status */
51 #define XHI_CYCLE_DONE              0
52 #define XHI_CYCLE_EXECUTING         1
53 
54 /* buffer_icap register offsets */
55 
56 /* Size of transfer, read & write */
57 #define XHI_SIZE_REG_OFFSET        0x800L
58 /* offset into bram, read & write */
59 #define XHI_BRAM_OFFSET_REG_OFFSET 0x804L
60 /* Read not Configure, direction of transfer.  Write only */
61 #define XHI_RNC_REG_OFFSET         0x808L
62 /* Indicates transfer complete. Read only */
63 #define XHI_STATUS_REG_OFFSET      0x80CL
64 
65 /* Constants for setting the RNC register */
66 #define XHI_CONFIGURE              0x0UL
67 #define XHI_READBACK               0x1UL
68 
69 /* Constants for the Done register */
70 #define XHI_NOT_FINISHED           0x0UL
71 #define XHI_FINISHED               0x1UL
72 
73 #define XHI_BUFFER_START 0
74 
75 /**
76  * buffer_icap_get_status - Get the contents of the status register.
77  * @base_address: is the base address of the device
78  *
79  * The status register contains the ICAP status and the done bit.
80  *
81  * D8 - cfgerr
82  * D7 - dalign
83  * D6 - rip
84  * D5 - in_abort_l
85  * D4 - Always 1
86  * D3 - Always 1
87  * D2 - Always 1
88  * D1 - Always 1
89  * D0 - Done bit
90  **/
91 static inline u32 buffer_icap_get_status(void __iomem *base_address)
92 {
93 	return in_be32(base_address + XHI_STATUS_REG_OFFSET);
94 }
95 
96 /**
97  * buffer_icap_get_bram - Reads data from the storage buffer bram.
98  * @base_address: contains the base address of the component.
99  * @offset: The word offset from which the data should be read.
100  *
101  * A bram is used as a configuration memory cache.  One frame of data can
102  * be stored in this "storage buffer".
103  **/
104 static inline u32 buffer_icap_get_bram(void __iomem *base_address,
105 		u32 offset)
106 {
107 	return in_be32(base_address + (offset << 2));
108 }
109 
110 /**
111  * buffer_icap_busy - Return true if the icap device is busy
112  * @base_address: is the base address of the device
113  *
114  * The queries the low order bit of the status register, which
115  * indicates whether the current configuration or readback operation
116  * has completed.
117  **/
118 static inline bool buffer_icap_busy(void __iomem *base_address)
119 {
120 	return (buffer_icap_get_status(base_address) & 1) == XHI_NOT_FINISHED;
121 }
122 
123 /**
124  * buffer_icap_busy - Return true if the icap device is not busy
125  * @base_address: is the base address of the device
126  *
127  * The queries the low order bit of the status register, which
128  * indicates whether the current configuration or readback operation
129  * has completed.
130  **/
131 static inline bool buffer_icap_done(void __iomem *base_address)
132 {
133 	return (buffer_icap_get_status(base_address) & 1) == XHI_FINISHED;
134 }
135 
136 /**
137  * buffer_icap_set_size - Set the size register.
138  * @base_address: is the base address of the device
139  * @data: The size in bytes.
140  *
141  * The size register holds the number of 8 bit bytes to transfer between
142  * bram and the icap (or icap to bram).
143  **/
144 static inline void buffer_icap_set_size(void __iomem *base_address,
145 		u32 data)
146 {
147 	out_be32(base_address + XHI_SIZE_REG_OFFSET, data);
148 }
149 
150 /**
151  * buffer_icap_set_offset - Set the bram offset register.
152  * @base_address: contains the base address of the device.
153  * @data: is the value to be written to the data register.
154  *
155  * The bram offset register holds the starting bram address to transfer
156  * data from during configuration or write data to during readback.
157  **/
158 static inline void buffer_icap_set_offset(void __iomem *base_address,
159 		u32 data)
160 {
161 	out_be32(base_address + XHI_BRAM_OFFSET_REG_OFFSET, data);
162 }
163 
164 /**
165  * buffer_icap_set_rnc - Set the RNC (Readback not Configure) register.
166  * @base_address: contains the base address of the device.
167  * @data: is the value to be written to the data register.
168  *
169  * The RNC register determines the direction of the data transfer.  It
170  * controls whether a configuration or readback take place.  Writing to
171  * this register initiates the transfer.  A value of 1 initiates a
172  * readback while writing a value of 0 initiates a configuration.
173  **/
174 static inline void buffer_icap_set_rnc(void __iomem *base_address,
175 		u32 data)
176 {
177 	out_be32(base_address + XHI_RNC_REG_OFFSET, data);
178 }
179 
180 /**
181  * buffer_icap_set_bram - Write data to the storage buffer bram.
182  * @base_address: contains the base address of the component.
183  * @offset: The word offset at which the data should be written.
184  * @data: The value to be written to the bram offset.
185  *
186  * A bram is used as a configuration memory cache.  One frame of data can
187  * be stored in this "storage buffer".
188  **/
189 static inline void buffer_icap_set_bram(void __iomem *base_address,
190 		u32 offset, u32 data)
191 {
192 	out_be32(base_address + (offset << 2), data);
193 }
194 
195 /**
196  * buffer_icap_device_read - Transfer bytes from ICAP to the storage buffer.
197  * @drvdata: a pointer to the drvdata.
198  * @offset: The storage buffer start address.
199  * @count: The number of words (32 bit) to read from the
200  *           device (ICAP).
201  **/
202 static int buffer_icap_device_read(struct hwicap_drvdata *drvdata,
203 		u32 offset, u32 count)
204 {
205 
206 	s32 retries = 0;
207 	void __iomem *base_address = drvdata->base_address;
208 
209 	if (buffer_icap_busy(base_address))
210 		return -EBUSY;
211 
212 	if ((offset + count) > XHI_MAX_BUFFER_INTS)
213 		return -EINVAL;
214 
215 	/* setSize count*4 to get bytes. */
216 	buffer_icap_set_size(base_address, (count << 2));
217 	buffer_icap_set_offset(base_address, offset);
218 	buffer_icap_set_rnc(base_address, XHI_READBACK);
219 
220 	while (buffer_icap_busy(base_address)) {
221 		retries++;
222 		if (retries > XHI_MAX_RETRIES)
223 			return -EBUSY;
224 	}
225 	return 0;
226 
227 };
228 
229 /**
230  * buffer_icap_device_write - Transfer bytes from ICAP to the storage buffer.
231  * @drvdata: a pointer to the drvdata.
232  * @offset: The storage buffer start address.
233  * @count: The number of words (32 bit) to read from the
234  *           device (ICAP).
235  **/
236 static int buffer_icap_device_write(struct hwicap_drvdata *drvdata,
237 		u32 offset, u32 count)
238 {
239 
240 	s32 retries = 0;
241 	void __iomem *base_address = drvdata->base_address;
242 
243 	if (buffer_icap_busy(base_address))
244 		return -EBUSY;
245 
246 	if ((offset + count) > XHI_MAX_BUFFER_INTS)
247 		return -EINVAL;
248 
249 	/* setSize count*4 to get bytes. */
250 	buffer_icap_set_size(base_address, count << 2);
251 	buffer_icap_set_offset(base_address, offset);
252 	buffer_icap_set_rnc(base_address, XHI_CONFIGURE);
253 
254 	while (buffer_icap_busy(base_address)) {
255 		retries++;
256 		if (retries > XHI_MAX_RETRIES)
257 			return -EBUSY;
258 	}
259 	return 0;
260 
261 };
262 
263 /**
264  * buffer_icap_reset - Reset the logic of the icap device.
265  * @drvdata: a pointer to the drvdata.
266  *
267  * Writing to the status register resets the ICAP logic in an internal
268  * version of the core.  For the version of the core published in EDK,
269  * this is a noop.
270  **/
271 void buffer_icap_reset(struct hwicap_drvdata *drvdata)
272 {
273     out_be32(drvdata->base_address + XHI_STATUS_REG_OFFSET, 0xFEFE);
274 }
275 
276 /**
277  * buffer_icap_set_configuration - Load a partial bitstream from system memory.
278  * @drvdata: a pointer to the drvdata.
279  * @data: Kernel address of the partial bitstream.
280  * @size: the size of the partial bitstream in 32 bit words.
281  **/
282 int buffer_icap_set_configuration(struct hwicap_drvdata *drvdata, u32 *data,
283 			     u32 size)
284 {
285 	int status;
286 	s32 buffer_count = 0;
287 	s32 num_writes = 0;
288 	bool dirty = 0;
289 	u32 i;
290 	void __iomem *base_address = drvdata->base_address;
291 
292 	/* Loop through all the data */
293 	for (i = 0, buffer_count = 0; i < size; i++) {
294 
295 		/* Copy data to bram */
296 		buffer_icap_set_bram(base_address, buffer_count, data[i]);
297 		dirty = 1;
298 
299 		if (buffer_count < XHI_MAX_BUFFER_INTS - 1) {
300 			buffer_count++;
301 			continue;
302 		}
303 
304 		/* Write data to ICAP */
305 		status = buffer_icap_device_write(
306 				drvdata,
307 				XHI_BUFFER_START,
308 				XHI_MAX_BUFFER_INTS);
309 		if (status != 0) {
310 			/* abort. */
311 			buffer_icap_reset(drvdata);
312 			return status;
313 		}
314 
315 		buffer_count = 0;
316 		num_writes++;
317 		dirty = 0;
318 	}
319 
320 	/* Write unwritten data to ICAP */
321 	if (dirty) {
322 		/* Write data to ICAP */
323 		status = buffer_icap_device_write(drvdata, XHI_BUFFER_START,
324 					     buffer_count);
325 		if (status != 0) {
326 			/* abort. */
327 			buffer_icap_reset(drvdata);
328 		}
329 		return status;
330 	}
331 
332 	return 0;
333 };
334 
335 /**
336  * buffer_icap_get_configuration - Read configuration data from the device.
337  * @drvdata: a pointer to the drvdata.
338  * @data: Address of the data representing the partial bitstream
339  * @size: the size of the partial bitstream in 32 bit words.
340  **/
341 int buffer_icap_get_configuration(struct hwicap_drvdata *drvdata, u32 *data,
342 			     u32 size)
343 {
344 	int status;
345 	s32 buffer_count = 0;
346 	s32 read_count = 0;
347 	u32 i;
348 	void __iomem *base_address = drvdata->base_address;
349 
350 	/* Loop through all the data */
351 	for (i = 0, buffer_count = XHI_MAX_BUFFER_INTS; i < size; i++) {
352 		if (buffer_count == XHI_MAX_BUFFER_INTS) {
353 			u32 words_remaining = size - i;
354 			u32 words_to_read =
355 				words_remaining <
356 				XHI_MAX_BUFFER_INTS ? words_remaining :
357 				XHI_MAX_BUFFER_INTS;
358 
359 			/* Read data from ICAP */
360 			status = buffer_icap_device_read(
361 					drvdata,
362 					XHI_BUFFER_START,
363 					words_to_read);
364 			if (status != 0) {
365 				/* abort. */
366 				buffer_icap_reset(drvdata);
367 				return status;
368 			}
369 
370 			buffer_count = 0;
371 			read_count++;
372 		}
373 
374 		/* Copy data from bram */
375 		data[i] = buffer_icap_get_bram(base_address, buffer_count);
376 		buffer_count++;
377 	}
378 
379 	return 0;
380 };
381