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-rw-r--r--drivers/mtd/devices/docprobe.c355
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diff --git a/drivers/mtd/devices/docprobe.c b/drivers/mtd/devices/docprobe.c
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1
2/* Linux driver for Disk-On-Chip devices */
3/* Probe routines common to all DoC devices */
4/* (C) 1999 Machine Vision Holdings, Inc. */
5/* (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> */
6
7/* $Id: docprobe.c,v 1.44 2005/01/05 12:40:36 dwmw2 Exp $ */
8
9
10
11/* DOC_PASSIVE_PROBE:
12 In order to ensure that the BIOS checksum is correct at boot time, and
13 hence that the onboard BIOS extension gets executed, the DiskOnChip
14 goes into reset mode when it is read sequentially: all registers
15 return 0xff until the chip is woken up again by writing to the
16 DOCControl register.
17
18 Unfortunately, this means that the probe for the DiskOnChip is unsafe,
19 because one of the first things it does is write to where it thinks
20 the DOCControl register should be - which may well be shared memory
21 for another device. I've had machines which lock up when this is
22 attempted. Hence the possibility to do a passive probe, which will fail
23 to detect a chip in reset mode, but is at least guaranteed not to lock
24 the machine.
25
26 If you have this problem, uncomment the following line:
27#define DOC_PASSIVE_PROBE
28*/
29
30
31/* DOC_SINGLE_DRIVER:
32 Millennium driver has been merged into DOC2000 driver.
33
34 The old Millennium-only driver has been retained just in case there
35 are problems with the new code. If the combined driver doesn't work
36 for you, you can try the old one by undefining DOC_SINGLE_DRIVER
37 below and also enabling it in your configuration. If this fixes the
38 problems, please send a report to the MTD mailing list at
39 <linux-mtd@lists.infradead.org>.
40*/
41#define DOC_SINGLE_DRIVER
42
43#include <linux/config.h>
44#include <linux/kernel.h>
45#include <linux/module.h>
46#include <asm/errno.h>
47#include <asm/io.h>
48#include <linux/delay.h>
49#include <linux/slab.h>
50#include <linux/init.h>
51#include <linux/types.h>
52
53#include <linux/mtd/mtd.h>
54#include <linux/mtd/nand.h>
55#include <linux/mtd/doc2000.h>
56#include <linux/mtd/compatmac.h>
57
58/* Where to look for the devices? */
59#ifndef CONFIG_MTD_DOCPROBE_ADDRESS
60#define CONFIG_MTD_DOCPROBE_ADDRESS 0
61#endif
62
63
64static unsigned long doc_config_location = CONFIG_MTD_DOCPROBE_ADDRESS;
65module_param(doc_config_location, ulong, 0);
66MODULE_PARM_DESC(doc_config_location, "Physical memory address at which to probe for DiskOnChip");
67
68static unsigned long __initdata doc_locations[] = {
69#if defined (__alpha__) || defined(__i386__) || defined(__x86_64__)
70#ifdef CONFIG_MTD_DOCPROBE_HIGH
71 0xfffc8000, 0xfffca000, 0xfffcc000, 0xfffce000,
72 0xfffd0000, 0xfffd2000, 0xfffd4000, 0xfffd6000,
73 0xfffd8000, 0xfffda000, 0xfffdc000, 0xfffde000,
74 0xfffe0000, 0xfffe2000, 0xfffe4000, 0xfffe6000,
75 0xfffe8000, 0xfffea000, 0xfffec000, 0xfffee000,
76#else /* CONFIG_MTD_DOCPROBE_HIGH */
77 0xc8000, 0xca000, 0xcc000, 0xce000,
78 0xd0000, 0xd2000, 0xd4000, 0xd6000,
79 0xd8000, 0xda000, 0xdc000, 0xde000,
80 0xe0000, 0xe2000, 0xe4000, 0xe6000,
81 0xe8000, 0xea000, 0xec000, 0xee000,
82#endif /* CONFIG_MTD_DOCPROBE_HIGH */
83#elif defined(__PPC__)
84 0xe4000000,
85#elif defined(CONFIG_MOMENCO_OCELOT)
86 0x2f000000,
87 0xff000000,
88#elif defined(CONFIG_MOMENCO_OCELOT_G) || defined (CONFIG_MOMENCO_OCELOT_C)
89 0xff000000,
90##else
91#warning Unknown architecture for DiskOnChip. No default probe locations defined
92#endif
93 0xffffffff };
94
95/* doccheck: Probe a given memory window to see if there's a DiskOnChip present */
96
97static inline int __init doccheck(void __iomem *potential, unsigned long physadr)
98{
99 void __iomem *window=potential;
100 unsigned char tmp, tmpb, tmpc, ChipID;
101#ifndef DOC_PASSIVE_PROBE
102 unsigned char tmp2;
103#endif
104
105 /* Routine copied from the Linux DOC driver */
106
107#ifdef CONFIG_MTD_DOCPROBE_55AA
108 /* Check for 0x55 0xAA signature at beginning of window,
109 this is no longer true once we remove the IPL (for Millennium */
110 if (ReadDOC(window, Sig1) != 0x55 || ReadDOC(window, Sig2) != 0xaa)
111 return 0;
112#endif /* CONFIG_MTD_DOCPROBE_55AA */
113
114#ifndef DOC_PASSIVE_PROBE
115 /* It's not possible to cleanly detect the DiskOnChip - the
116 * bootup procedure will put the device into reset mode, and
117 * it's not possible to talk to it without actually writing
118 * to the DOCControl register. So we store the current contents
119 * of the DOCControl register's location, in case we later decide
120 * that it's not a DiskOnChip, and want to put it back how we
121 * found it.
122 */
123 tmp2 = ReadDOC(window, DOCControl);
124
125 /* Reset the DiskOnChip ASIC */
126 WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
127 window, DOCControl);
128 WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
129 window, DOCControl);
130
131 /* Enable the DiskOnChip ASIC */
132 WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
133 window, DOCControl);
134 WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
135 window, DOCControl);
136#endif /* !DOC_PASSIVE_PROBE */
137
138 /* We need to read the ChipID register four times. For some
139 newer DiskOnChip 2000 units, the first three reads will
140 return the DiskOnChip Millennium ident. Don't ask. */
141 ChipID = ReadDOC(window, ChipID);
142
143 switch (ChipID) {
144 case DOC_ChipID_Doc2k:
145 /* Check the TOGGLE bit in the ECC register */
146 tmp = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
147 tmpb = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
148 tmpc = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
149 if (tmp != tmpb && tmp == tmpc)
150 return ChipID;
151 break;
152
153 case DOC_ChipID_DocMil:
154 /* Check for the new 2000 with Millennium ASIC */
155 ReadDOC(window, ChipID);
156 ReadDOC(window, ChipID);
157 if (ReadDOC(window, ChipID) != DOC_ChipID_DocMil)
158 ChipID = DOC_ChipID_Doc2kTSOP;
159
160 /* Check the TOGGLE bit in the ECC register */
161 tmp = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
162 tmpb = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
163 tmpc = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
164 if (tmp != tmpb && tmp == tmpc)
165 return ChipID;
166 break;
167
168 case DOC_ChipID_DocMilPlus16:
169 case DOC_ChipID_DocMilPlus32:
170 case 0:
171 /* Possible Millennium+, need to do more checks */
172#ifndef DOC_PASSIVE_PROBE
173 /* Possibly release from power down mode */
174 for (tmp = 0; (tmp < 4); tmp++)
175 ReadDOC(window, Mplus_Power);
176
177 /* Reset the DiskOnChip ASIC */
178 tmp = DOC_MODE_RESET | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
179 DOC_MODE_BDECT;
180 WriteDOC(tmp, window, Mplus_DOCControl);
181 WriteDOC(~tmp, window, Mplus_CtrlConfirm);
182
183 mdelay(1);
184 /* Enable the DiskOnChip ASIC */
185 tmp = DOC_MODE_NORMAL | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
186 DOC_MODE_BDECT;
187 WriteDOC(tmp, window, Mplus_DOCControl);
188 WriteDOC(~tmp, window, Mplus_CtrlConfirm);
189 mdelay(1);
190#endif /* !DOC_PASSIVE_PROBE */
191
192 ChipID = ReadDOC(window, ChipID);
193
194 switch (ChipID) {
195 case DOC_ChipID_DocMilPlus16:
196 case DOC_ChipID_DocMilPlus32:
197 /* Check the TOGGLE bit in the toggle register */
198 tmp = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
199 tmpb = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
200 tmpc = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
201 if (tmp != tmpb && tmp == tmpc)
202 return ChipID;
203 default:
204 break;
205 }
206 /* FALL TRHU */
207
208 default:
209
210#ifdef CONFIG_MTD_DOCPROBE_55AA
211 printk(KERN_DEBUG "Possible DiskOnChip with unknown ChipID %2.2X found at 0x%lx\n",
212 ChipID, physadr);
213#endif
214#ifndef DOC_PASSIVE_PROBE
215 /* Put back the contents of the DOCControl register, in case it's not
216 * actually a DiskOnChip.
217 */
218 WriteDOC(tmp2, window, DOCControl);
219#endif
220 return 0;
221 }
222
223 printk(KERN_WARNING "DiskOnChip failed TOGGLE test, dropping.\n");
224
225#ifndef DOC_PASSIVE_PROBE
226 /* Put back the contents of the DOCControl register: it's not a DiskOnChip */
227 WriteDOC(tmp2, window, DOCControl);
228#endif
229 return 0;
230}
231
232static int docfound;
233
234static void __init DoC_Probe(unsigned long physadr)
235{
236 void __iomem *docptr;
237 struct DiskOnChip *this;
238 struct mtd_info *mtd;
239 int ChipID;
240 char namebuf[15];
241 char *name = namebuf;
242 char *im_funcname = NULL;
243 char *im_modname = NULL;
244 void (*initroutine)(struct mtd_info *) = NULL;
245
246 docptr = ioremap(physadr, DOC_IOREMAP_LEN);
247
248 if (!docptr)
249 return;
250
251 if ((ChipID = doccheck(docptr, physadr))) {
252 if (ChipID == DOC_ChipID_Doc2kTSOP) {
253 /* Remove this at your own peril. The hardware driver works but nothing prevents you from erasing bad blocks */
254 printk(KERN_NOTICE "Refusing to drive DiskOnChip 2000 TSOP until Bad Block Table is correctly supported by INFTL\n");
255 iounmap(docptr);
256 return;
257 }
258 docfound = 1;
259 mtd = kmalloc(sizeof(struct DiskOnChip) + sizeof(struct mtd_info), GFP_KERNEL);
260
261 if (!mtd) {
262 printk(KERN_WARNING "Cannot allocate memory for data structures. Dropping.\n");
263 iounmap(docptr);
264 return;
265 }
266
267 this = (struct DiskOnChip *)(&mtd[1]);
268
269 memset((char *)mtd,0, sizeof(struct mtd_info));
270 memset((char *)this, 0, sizeof(struct DiskOnChip));
271
272 mtd->priv = this;
273 this->virtadr = docptr;
274 this->physadr = physadr;
275 this->ChipID = ChipID;
276 sprintf(namebuf, "with ChipID %2.2X", ChipID);
277
278 switch(ChipID) {
279 case DOC_ChipID_Doc2kTSOP:
280 name="2000 TSOP";
281 im_funcname = "DoC2k_init";
282 im_modname = "doc2000";
283 break;
284
285 case DOC_ChipID_Doc2k:
286 name="2000";
287 im_funcname = "DoC2k_init";
288 im_modname = "doc2000";
289 break;
290
291 case DOC_ChipID_DocMil:
292 name="Millennium";
293#ifdef DOC_SINGLE_DRIVER
294 im_funcname = "DoC2k_init";
295 im_modname = "doc2000";
296#else
297 im_funcname = "DoCMil_init";
298 im_modname = "doc2001";
299#endif /* DOC_SINGLE_DRIVER */
300 break;
301
302 case DOC_ChipID_DocMilPlus16:
303 case DOC_ChipID_DocMilPlus32:
304 name="MillenniumPlus";
305 im_funcname = "DoCMilPlus_init";
306 im_modname = "doc2001plus";
307 break;
308 }
309
310 if (im_funcname)
311 initroutine = inter_module_get_request(im_funcname, im_modname);
312
313 if (initroutine) {
314 (*initroutine)(mtd);
315 inter_module_put(im_funcname);
316 return;
317 }
318 printk(KERN_NOTICE "Cannot find driver for DiskOnChip %s at 0x%lX\n", name, physadr);
319 kfree(mtd);
320 }
321 iounmap(docptr);
322}
323
324
325/****************************************************************************
326 *
327 * Module stuff
328 *
329 ****************************************************************************/
330
331static int __init init_doc(void)
332{
333 int i;
334
335 if (doc_config_location) {
336 printk(KERN_INFO "Using configured DiskOnChip probe address 0x%lx\n", doc_config_location);
337 DoC_Probe(doc_config_location);
338 } else {
339 for (i=0; (doc_locations[i] != 0xffffffff); i++) {
340 DoC_Probe(doc_locations[i]);
341 }
342 }
343 /* No banner message any more. Print a message if no DiskOnChip
344 found, so the user knows we at least tried. */
345 if (!docfound)
346 printk(KERN_INFO "No recognised DiskOnChip devices found\n");
347 return -EAGAIN;
348}
349
350module_init(init_doc);
351
352MODULE_LICENSE("GPL");
353MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
354MODULE_DESCRIPTION("Probe code for DiskOnChip 2000 and Millennium devices");
355