summaryrefslogtreecommitdiff
path: root/drivers/systemace.c
blob: 1d1be12520295f0094594eab200935e25e0a9524 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
/*
 * Copyright (c) 2004 Picture Elements, Inc.
 *    Stephen Williams (XXXXXXXXXXXXXXXX)
 *
 *    This source code is free software; you can redistribute it
 *    and/or modify it in source code form under the terms of the GNU
 *    General Public License as published by the Free Software
 *    Foundation; either version 2 of the License, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

/*
 * The Xilinx SystemACE chip support is activated by defining
 * CONFIG_SYSTEMACE to turn on support, and CFG_SYSTEMACE_BASE
 * to set the base address of the device. This code currently
 * assumes that the chip is connected via a byte-wide bus.
 *
 * The CONFIG_SYSTEMACE also adds to fat support the device class
 * "ace" that allows the user to execute "fatls ace 0" and the
 * like. This works by making the systemace_get_dev function
 * available to cmd_fat.c:get_dev and filling in a block device
 * description that has all the bits needed for FAT support to
 * read sectors.
 *
 * According to Xilinx technical support, before accessing the
 * SystemACE CF you need to set the following control bits:
 *      FORCECFGMODE : 1
 *      CFGMODE : 0
 *      CFGSTART : 0
 */

#include <common.h>
#include <command.h>
#include <systemace.h>
#include <part.h>
#include <asm/io.h>

#ifdef CONFIG_SYSTEMACE

/*
 * The ace_readw and writew functions read/write 16bit words, but the
 * offset value is the BYTE offset as most used in the Xilinx
 * datasheet for the SystemACE chip. The CFG_SYSTEMACE_BASE is defined
 * to be the base address for the chip, usually in the local
 * peripheral bus.
 */
#if (CFG_SYSTEMACE_WIDTH == 8)
#if !defined(__BIG_ENDIAN)
#define ace_readw(off) ((readb(CFG_SYSTEMACE_BASE+off)<<8) | \
                        (readb(CFG_SYSTEMACE_BASE+off+1)))
#define ace_writew(val, off) {writeb(val>>8, CFG_SYSTEMACE_BASE+off); \
			      writeb(val, CFG_SYSTEMACE_BASE+off+1);}
#else
#define ace_readw(off) ((readb(CFG_SYSTEMACE_BASE+off)) | \
                        (readb(CFG_SYSTEMACE_BASE+off+1)<<8))
#define ace_writew(val, off) {writeb(val, CFG_SYSTEMACE_BASE+off); \
			      writeb(val>>8, CFG_SYSTEMACE_BASE+off+1);}
#endif
#else
#define ace_readw(off) (in16(CFG_SYSTEMACE_BASE+off))
#define ace_writew(val, off) (out16(CFG_SYSTEMACE_BASE+off,val))
#endif

/* */

static unsigned long systemace_read(int dev, unsigned long start,
                                    unsigned long blkcnt, void *buffer);

static block_dev_desc_t systemace_dev = { 0 };

static int get_cf_lock(void)
{
	int retry = 10;

	/* CONTROLREG = LOCKREG */
	unsigned val = ace_readw(0x18);
	val |= 0x0002;
	ace_writew((val & 0xffff), 0x18);

	/* Wait for MPULOCK in STATUSREG[15:0] */
	while (!(ace_readw(0x04) & 0x0002)) {

		if (retry < 0)
			return -1;

		udelay(100000);
		retry -= 1;
	}

	return 0;
}

static void release_cf_lock(void)
{
	unsigned val = ace_readw(0x18);
	val &= ~(0x0002);
	ace_writew((val & 0xffff), 0x18);
}

block_dev_desc_t *systemace_get_dev(int dev)
{
	/* The first time through this, the systemace_dev object is
	   not yet initialized. In that case, fill it in. */
	if (systemace_dev.blksz == 0) {
		systemace_dev.if_type = IF_TYPE_UNKNOWN;
		systemace_dev.dev = 0;
		systemace_dev.part_type = PART_TYPE_UNKNOWN;
		systemace_dev.type = DEV_TYPE_HARDDISK;
		systemace_dev.blksz = 512;
		systemace_dev.removable = 1;
		systemace_dev.block_read = systemace_read;

#if (CFG_SYSTEMACE_WIDTH == 16)
		/*
		 * By default the SystemACE comes up in 8-bit mode.
		 * Ensure that 16-bit mode gets enabled.
		 */
		ace_writew(0x0001, 0);
#endif

		init_part(&systemace_dev);

	}

	return &systemace_dev;
}

/*
 * This function is called (by dereferencing the block_read pointer in
 * the dev_desc) to read blocks of data. The return value is the
 * number of blocks read. A zero return indicates an error.
 */
static unsigned long systemace_read(int dev, unsigned long start,
                                    unsigned long blkcnt, void *buffer)
{
	int retry;
	unsigned blk_countdown;
	unsigned char *dp = buffer;
	unsigned val;

	if (get_cf_lock() < 0) {
		unsigned status = ace_readw(0x04);

		/* If CFDETECT is false, card is missing. */
		if (!(status & 0x0010)) {
			printf("** CompactFlash card not present. **\n");
			return 0;
		}

		printf("**** ACE locked away from me (STATUSREG=%04x)\n",
		       status);
		return 0;
	}
#ifdef DEBUG_SYSTEMACE
	printf("... systemace read %lu sectors at %lu\n", blkcnt, start);
#endif

	retry = 2000;
	for (;;) {
		val = ace_readw(0x04);

		/* If CFDETECT is false, card is missing. */
		if (!(val & 0x0010)) {
			printf("**** ACE CompactFlash not found.\n");
			release_cf_lock();
			return 0;
		}

		/* If RDYFORCMD, then we are ready to go. */
		if (val & 0x0100)
			break;

		if (retry < 0) {
			printf("**** SystemACE not ready.\n");
			release_cf_lock();
			return 0;
		}

		udelay(1000);
		retry -= 1;
	}

	/* The SystemACE can only transfer 256 sectors at a time, so
	   limit the current chunk of sectors. The blk_countdown
	   variable is the number of sectors left to transfer. */

	blk_countdown = blkcnt;
	while (blk_countdown > 0) {
		unsigned trans = blk_countdown;

		if (trans > 256)
			trans = 256;

#ifdef DEBUG_SYSTEMACE
		printf("... transfer %lu sector in a chunk\n", trans);
#endif
		/* Write LBA block address */
		ace_writew((start >> 0) & 0xffff, 0x10);
		ace_writew((start >> 16) & 0x0fff, 0x12);

		/* NOTE: in the Write Sector count below, a count of 0
		   causes a transfer of 256, so &0xff gives the right
		   value for whatever transfer count we want. */

		/* Write sector count | ReadMemCardData. */
		ace_writew((trans & 0xff) | 0x0300, 0x14);

		/* Reset the configruation controller */
		val = ace_readw(0x18);
		val |= 0x0080;
		ace_writew(val, 0x18);

		retry = trans * 16;
		while (retry > 0) {
			int idx;

			/* Wait for buffer to become ready. */
			while (!(ace_readw(0x04) & 0x0020)) {
				udelay(100);
			}

			/* Read 16 words of 2bytes from the sector buffer. */
			for (idx = 0; idx < 16; idx += 1) {
				unsigned short val = ace_readw(0x40);
				*dp++ = val & 0xff;
				*dp++ = (val >> 8) & 0xff;
			}

			retry -= 1;
		}

		/* Clear the configruation controller reset */
		val = ace_readw(0x18);
		val &= ~0x0080;
		ace_writew(val, 0x18);

		/* Count the blocks we transfer this time. */
		start += trans;
		blk_countdown -= trans;
	}

	release_cf_lock();

	return blkcnt;
}
#endif /* CONFIG_SYSTEMACE */