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