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.
9  *
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  * @drvdata: a pointer to the drvdata.
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 u32 buffer_icap_get_status(struct hwicap_drvdata *drvdata)
92 {
93 	return in_be32(drvdata->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 	u32 status = in_be32(base_address + XHI_STATUS_REG_OFFSET);
121 	return (status & 1) == XHI_NOT_FINISHED;
122 }
123 
124 /**
125  * buffer_icap_set_size - Set the size register.
126  * @base_address: is the base address of the device
127  * @data: The size in bytes.
128  *
129  * The size register holds the number of 8 bit bytes to transfer between
130  * bram and the icap (or icap to bram).
131  **/
132 static inline void buffer_icap_set_size(void __iomem *base_address,
133 		u32 data)
134 {
135 	out_be32(base_address + XHI_SIZE_REG_OFFSET, data);
136 }
137 
138 /**
139  * buffer_icap_set_offset - Set the bram offset register.
140  * @base_address: contains the base address of the device.
141  * @data: is the value to be written to the data register.
142  *
143  * The bram offset register holds the starting bram address to transfer
144  * data from during configuration or write data to during readback.
145  **/
146 static inline void buffer_icap_set_offset(void __iomem *base_address,
147 		u32 data)
148 {
149 	out_be32(base_address + XHI_BRAM_OFFSET_REG_OFFSET, data);
150 }
151 
152 /**
153  * buffer_icap_set_rnc - Set the RNC (Readback not Configure) register.
154  * @base_address: contains the base address of the device.
155  * @data: is the value to be written to the data register.
156  *
157  * The RNC register determines the direction of the data transfer.  It
158  * controls whether a configuration or readback take place.  Writing to
159  * this register initiates the transfer.  A value of 1 initiates a
160  * readback while writing a value of 0 initiates a configuration.
161  **/
162 static inline void buffer_icap_set_rnc(void __iomem *base_address,
163 		u32 data)
164 {
165 	out_be32(base_address + XHI_RNC_REG_OFFSET, data);
166 }
167 
168 /**
169  * buffer_icap_set_bram - Write data to the storage buffer bram.
170  * @base_address: contains the base address of the component.
171  * @offset: The word offset at which the data should be written.
172  * @data: The value to be written to the bram offset.
173  *
174  * A bram is used as a configuration memory cache.  One frame of data can
175  * be stored in this "storage buffer".
176  **/
177 static inline void buffer_icap_set_bram(void __iomem *base_address,
178 		u32 offset, u32 data)
179 {
180 	out_be32(base_address + (offset << 2), data);
181 }
182 
183 /**
184  * buffer_icap_device_read - Transfer bytes from ICAP to the storage buffer.
185  * @drvdata: a pointer to the drvdata.
186  * @offset: The storage buffer start address.
187  * @count: The number of words (32 bit) to read from the
188  *           device (ICAP).
189  **/
190 static int buffer_icap_device_read(struct hwicap_drvdata *drvdata,
191 		u32 offset, u32 count)
192 {
193 
194 	s32 retries = 0;
195 	void __iomem *base_address = drvdata->base_address;
196 
197 	if (buffer_icap_busy(base_address))
198 		return -EBUSY;
199 
200 	if ((offset + count) > XHI_MAX_BUFFER_INTS)
201 		return -EINVAL;
202 
203 	/* setSize count*4 to get bytes. */
204 	buffer_icap_set_size(base_address, (count << 2));
205 	buffer_icap_set_offset(base_address, offset);
206 	buffer_icap_set_rnc(base_address, XHI_READBACK);
207 
208 	while (buffer_icap_busy(base_address)) {
209 		retries++;
210 		if (retries > XHI_MAX_RETRIES)
211 			return -EBUSY;
212 	}
213 	return 0;
214 
215 };
216 
217 /**
218  * buffer_icap_device_write - Transfer bytes from ICAP to the storage buffer.
219  * @drvdata: a pointer to the drvdata.
220  * @offset: The storage buffer start address.
221  * @count: The number of words (32 bit) to read from the
222  *           device (ICAP).
223  **/
224 static int buffer_icap_device_write(struct hwicap_drvdata *drvdata,
225 		u32 offset, u32 count)
226 {
227 
228 	s32 retries = 0;
229 	void __iomem *base_address = drvdata->base_address;
230 
231 	if (buffer_icap_busy(base_address))
232 		return -EBUSY;
233 
234 	if ((offset + count) > XHI_MAX_BUFFER_INTS)
235 		return -EINVAL;
236 
237 	/* setSize count*4 to get bytes. */
238 	buffer_icap_set_size(base_address, count << 2);
239 	buffer_icap_set_offset(base_address, offset);
240 	buffer_icap_set_rnc(base_address, XHI_CONFIGURE);
241 
242 	while (buffer_icap_busy(base_address)) {
243 		retries++;
244 		if (retries > XHI_MAX_RETRIES)
245 			return -EBUSY;
246 	}
247 	return 0;
248 
249 };
250 
251 /**
252  * buffer_icap_reset - Reset the logic of the icap device.
253  * @drvdata: a pointer to the drvdata.
254  *
255  * Writing to the status register resets the ICAP logic in an internal
256  * version of the core.  For the version of the core published in EDK,
257  * this is a noop.
258  **/
259 void buffer_icap_reset(struct hwicap_drvdata *drvdata)
260 {
261     out_be32(drvdata->base_address + XHI_STATUS_REG_OFFSET, 0xFEFE);
262 }
263 
264 /**
265  * buffer_icap_set_configuration - Load a partial bitstream from system memory.
266  * @drvdata: a pointer to the drvdata.
267  * @data: Kernel address of the partial bitstream.
268  * @size: the size of the partial bitstream in 32 bit words.
269  **/
270 int buffer_icap_set_configuration(struct hwicap_drvdata *drvdata, u32 *data,
271 			     u32 size)
272 {
273 	int status;
274 	s32 buffer_count = 0;
275 	s32 num_writes = 0;
276 	bool dirty = 0;
277 	u32 i;
278 	void __iomem *base_address = drvdata->base_address;
279 
280 	/* Loop through all the data */
281 	for (i = 0, buffer_count = 0; i < size; i++) {
282 
283 		/* Copy data to bram */
284 		buffer_icap_set_bram(base_address, buffer_count, data[i]);
285 		dirty = 1;
286 
287 		if (buffer_count < XHI_MAX_BUFFER_INTS - 1) {
288 			buffer_count++;
289 			continue;
290 		}
291 
292 		/* Write data to ICAP */
293 		status = buffer_icap_device_write(
294 				drvdata,
295 				XHI_BUFFER_START,
296 				XHI_MAX_BUFFER_INTS);
297 		if (status != 0) {
298 			/* abort. */
299 			buffer_icap_reset(drvdata);
300 			return status;
301 		}
302 
303 		buffer_count = 0;
304 		num_writes++;
305 		dirty = 0;
306 	}
307 
308 	/* Write unwritten data to ICAP */
309 	if (dirty) {
310 		/* Write data to ICAP */
311 		status = buffer_icap_device_write(drvdata, XHI_BUFFER_START,
312 					     buffer_count);
313 		if (status != 0) {
314 			/* abort. */
315 			buffer_icap_reset(drvdata);
316 		}
317 		return status;
318 	}
319 
320 	return 0;
321 };
322 
323 /**
324  * buffer_icap_get_configuration - Read configuration data from the device.
325  * @drvdata: a pointer to the drvdata.
326  * @data: Address of the data representing the partial bitstream
327  * @size: the size of the partial bitstream in 32 bit words.
328  **/
329 int buffer_icap_get_configuration(struct hwicap_drvdata *drvdata, u32 *data,
330 			     u32 size)
331 {
332 	int status;
333 	s32 buffer_count = 0;
334 	s32 read_count = 0;
335 	u32 i;
336 	void __iomem *base_address = drvdata->base_address;
337 
338 	/* Loop through all the data */
339 	for (i = 0, buffer_count = XHI_MAX_BUFFER_INTS; i < size; i++) {
340 		if (buffer_count == XHI_MAX_BUFFER_INTS) {
341 			u32 words_remaining = size - i;
342 			u32 words_to_read =
343 				words_remaining <
344 				XHI_MAX_BUFFER_INTS ? words_remaining :
345 				XHI_MAX_BUFFER_INTS;
346 
347 			/* Read data from ICAP */
348 			status = buffer_icap_device_read(
349 					drvdata,
350 					XHI_BUFFER_START,
351 					words_to_read);
352 			if (status != 0) {
353 				/* abort. */
354 				buffer_icap_reset(drvdata);
355 				return status;
356 			}
357 
358 			buffer_count = 0;
359 			read_count++;
360 		}
361 
362 		/* Copy data from bram */
363 		data[i] = buffer_icap_get_bram(base_address, buffer_count);
364 		buffer_count++;
365 	}
366 
367 	return 0;
368 };
369