docprobe.c 10.1 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8

/* Linux driver for Disk-On-Chip devices			*/
/* Probe routines common to all DoC devices			*/
/* (C) 1999 Machine Vision Holdings, Inc.			*/
/* (C) 1999-2003 David Woodhouse <dwmw2@infradead.org>		*/


/* DOC_PASSIVE_PROBE:
9 10 11 12 13 14 15 16 17 18 19
   In order to ensure that the BIOS checksum is correct at boot time, and
   hence that the onboard BIOS extension gets executed, the DiskOnChip
   goes into reset mode when it is read sequentially: all registers
   return 0xff until the chip is woken up again by writing to the
   DOCControl register.

   Unfortunately, this means that the probe for the DiskOnChip is unsafe,
   because one of the first things it does is write to where it thinks
   the DOCControl register should be - which may well be shared memory
   for another device. I've had machines which lock up when this is
   attempted. Hence the possibility to do a passive probe, which will fail
L
Linus Torvalds 已提交
20 21 22 23 24 25 26 27 28 29 30 31 32
   to detect a chip in reset mode, but is at least guaranteed not to lock
   the machine.

   If you have this problem, uncomment the following line:
#define DOC_PASSIVE_PROBE
*/


/* DOC_SINGLE_DRIVER:
   Millennium driver has been merged into DOC2000 driver.

   The old Millennium-only driver has been retained just in case there
   are problems with the new code. If the combined driver doesn't work
33
   for you, you can try the old one by undefining DOC_SINGLE_DRIVER
L
Linus Torvalds 已提交
34
   below and also enabling it in your configuration. If this fixes the
35
   problems, please send a report to the MTD mailing list at
L
Linus Torvalds 已提交
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
   <linux-mtd@lists.infradead.org>.
*/
#define DOC_SINGLE_DRIVER

#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/doc2000.h>

/* Where to look for the devices? */
#ifndef CONFIG_MTD_DOCPROBE_ADDRESS
#define CONFIG_MTD_DOCPROBE_ADDRESS 0
#endif


static unsigned long doc_config_location = CONFIG_MTD_DOCPROBE_ADDRESS;
module_param(doc_config_location, ulong, 0);
MODULE_PARM_DESC(doc_config_location, "Physical memory address at which to probe for DiskOnChip");

static unsigned long __initdata doc_locations[] = {
#if defined (__alpha__) || defined(__i386__) || defined(__x86_64__)
#ifdef CONFIG_MTD_DOCPROBE_HIGH
66
	0xfffc8000, 0xfffca000, 0xfffcc000, 0xfffce000,
L
Linus Torvalds 已提交
67
	0xfffd0000, 0xfffd2000, 0xfffd4000, 0xfffd6000,
68 69
	0xfffd8000, 0xfffda000, 0xfffdc000, 0xfffde000,
	0xfffe0000, 0xfffe2000, 0xfffe4000, 0xfffe6000,
L
Linus Torvalds 已提交
70 71
	0xfffe8000, 0xfffea000, 0xfffec000, 0xfffee000,
#else /*  CONFIG_MTD_DOCPROBE_HIGH */
72
	0xc8000, 0xca000, 0xcc000, 0xce000,
L
Linus Torvalds 已提交
73
	0xd0000, 0xd2000, 0xd4000, 0xd6000,
74 75
	0xd8000, 0xda000, 0xdc000, 0xde000,
	0xe0000, 0xe2000, 0xe4000, 0xe6000,
L
Linus Torvalds 已提交
76 77
	0xe8000, 0xea000, 0xec000, 0xee000,
#endif /*  CONFIG_MTD_DOCPROBE_HIGH */
78
#else
L
Linus Torvalds 已提交
79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101
#warning Unknown architecture for DiskOnChip. No default probe locations defined
#endif
	0xffffffff };

/* doccheck: Probe a given memory window to see if there's a DiskOnChip present */

static inline int __init doccheck(void __iomem *potential, unsigned long physadr)
{
	void __iomem *window=potential;
	unsigned char tmp, tmpb, tmpc, ChipID;
#ifndef DOC_PASSIVE_PROBE
	unsigned char tmp2;
#endif

	/* Routine copied from the Linux DOC driver */

#ifdef CONFIG_MTD_DOCPROBE_55AA
	/* Check for 0x55 0xAA signature at beginning of window,
	   this is no longer true once we remove the IPL (for Millennium */
	if (ReadDOC(window, Sig1) != 0x55 || ReadDOC(window, Sig2) != 0xaa)
		return 0;
#endif /* CONFIG_MTD_DOCPROBE_55AA */

102
#ifndef DOC_PASSIVE_PROBE
L
Linus Torvalds 已提交
103 104 105 106 107 108
	/* It's not possible to cleanly detect the DiskOnChip - the
	 * bootup procedure will put the device into reset mode, and
	 * it's not possible to talk to it without actually writing
	 * to the DOCControl register. So we store the current contents
	 * of the DOCControl register's location, in case we later decide
	 * that it's not a DiskOnChip, and want to put it back how we
109
	 * found it.
L
Linus Torvalds 已提交
110 111
	 */
	tmp2 = ReadDOC(window, DOCControl);
112

L
Linus Torvalds 已提交
113
	/* Reset the DiskOnChip ASIC */
114
	WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
L
Linus Torvalds 已提交
115
		 window, DOCControl);
116
	WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
L
Linus Torvalds 已提交
117
		 window, DOCControl);
118

L
Linus Torvalds 已提交
119
	/* Enable the DiskOnChip ASIC */
120
	WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
L
Linus Torvalds 已提交
121
		 window, DOCControl);
122
	WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
L
Linus Torvalds 已提交
123
		 window, DOCControl);
124
#endif /* !DOC_PASSIVE_PROBE */
L
Linus Torvalds 已提交
125 126 127 128 129

	/* We need to read the ChipID register four times. For some
	   newer DiskOnChip 2000 units, the first three reads will
	   return the DiskOnChip Millennium ident. Don't ask. */
	ChipID = ReadDOC(window, ChipID);
130

L
Linus Torvalds 已提交
131 132 133 134 135 136 137 138 139
	switch (ChipID) {
	case DOC_ChipID_Doc2k:
		/* Check the TOGGLE bit in the ECC register */
		tmp  = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
		tmpb = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
		tmpc = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
		if (tmp != tmpb && tmp == tmpc)
				return ChipID;
		break;
140

L
Linus Torvalds 已提交
141 142 143 144 145 146 147 148 149 150 151 152 153 154
	case DOC_ChipID_DocMil:
		/* Check for the new 2000 with Millennium ASIC */
		ReadDOC(window, ChipID);
		ReadDOC(window, ChipID);
		if (ReadDOC(window, ChipID) != DOC_ChipID_DocMil)
			ChipID = DOC_ChipID_Doc2kTSOP;

		/* Check the TOGGLE bit in the ECC register */
		tmp  = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
		tmpb = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
		tmpc = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
		if (tmp != tmpb && tmp == tmpc)
				return ChipID;
		break;
155

L
Linus Torvalds 已提交
156 157 158 159 160 161 162 163 164 165 166 167 168 169
	case DOC_ChipID_DocMilPlus16:
	case DOC_ChipID_DocMilPlus32:
	case 0:
		/* Possible Millennium+, need to do more checks */
#ifndef DOC_PASSIVE_PROBE
		/* Possibly release from power down mode */
		for (tmp = 0; (tmp < 4); tmp++)
			ReadDOC(window, Mplus_Power);

		/* Reset the DiskOnChip ASIC */
		tmp = DOC_MODE_RESET | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
			DOC_MODE_BDECT;
		WriteDOC(tmp, window, Mplus_DOCControl);
		WriteDOC(~tmp, window, Mplus_CtrlConfirm);
170

L
Linus Torvalds 已提交
171 172 173 174 175 176 177
		mdelay(1);
		/* Enable the DiskOnChip ASIC */
		tmp = DOC_MODE_NORMAL | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
			DOC_MODE_BDECT;
		WriteDOC(tmp, window, Mplus_DOCControl);
		WriteDOC(~tmp, window, Mplus_CtrlConfirm);
		mdelay(1);
178
#endif /* !DOC_PASSIVE_PROBE */
L
Linus Torvalds 已提交
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

		ChipID = ReadDOC(window, ChipID);

		switch (ChipID) {
		case DOC_ChipID_DocMilPlus16:
		case DOC_ChipID_DocMilPlus32:
			/* Check the TOGGLE bit in the toggle register */
			tmp  = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
			tmpb = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
			tmpc = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
			if (tmp != tmpb && tmp == tmpc)
					return ChipID;
		default:
			break;
		}
		/* FALL TRHU */

	default:

#ifdef CONFIG_MTD_DOCPROBE_55AA
		printk(KERN_DEBUG "Possible DiskOnChip with unknown ChipID %2.2X found at 0x%lx\n",
		       ChipID, physadr);
#endif
#ifndef DOC_PASSIVE_PROBE
		/* Put back the contents of the DOCControl register, in case it's not
		 * actually a DiskOnChip.
		 */
		WriteDOC(tmp2, window, DOCControl);
#endif
		return 0;
	}

	printk(KERN_WARNING "DiskOnChip failed TOGGLE test, dropping.\n");

#ifndef DOC_PASSIVE_PROBE
	/* Put back the contents of the DOCControl register: it's not a DiskOnChip */
	WriteDOC(tmp2, window, DOCControl);
#endif
	return 0;
218
}
L
Linus Torvalds 已提交
219 220 221

static int docfound;

222 223 224 225
extern void DoC2k_init(struct mtd_info *);
extern void DoCMil_init(struct mtd_info *);
extern void DoCMilPlus_init(struct mtd_info *);

L
Linus Torvalds 已提交
226 227 228 229 230 231 232 233 234 235 236
static void __init DoC_Probe(unsigned long physadr)
{
	void __iomem *docptr;
	struct DiskOnChip *this;
	struct mtd_info *mtd;
	int ChipID;
	char namebuf[15];
	char *name = namebuf;
	void (*initroutine)(struct mtd_info *) = NULL;

	docptr = ioremap(physadr, DOC_IOREMAP_LEN);
237

L
Linus Torvalds 已提交
238 239
	if (!docptr)
		return;
240

L
Linus Torvalds 已提交
241 242 243 244 245 246 247 248 249 250 251 252 253 254 255
	if ((ChipID = doccheck(docptr, physadr))) {
		if (ChipID == DOC_ChipID_Doc2kTSOP) {
			/* Remove this at your own peril. The hardware driver works but nothing prevents you from erasing bad blocks */
			printk(KERN_NOTICE "Refusing to drive DiskOnChip 2000 TSOP until Bad Block Table is correctly supported by INFTL\n");
			iounmap(docptr);
			return;
		}
		docfound = 1;
		mtd = kmalloc(sizeof(struct DiskOnChip) + sizeof(struct mtd_info), GFP_KERNEL);

		if (!mtd) {
			printk(KERN_WARNING "Cannot allocate memory for data structures. Dropping.\n");
			iounmap(docptr);
			return;
		}
256

L
Linus Torvalds 已提交
257
		this = (struct DiskOnChip *)(&mtd[1]);
258

L
Linus Torvalds 已提交
259 260 261 262 263 264 265 266 267 268 269 270
		memset((char *)mtd,0, sizeof(struct mtd_info));
		memset((char *)this, 0, sizeof(struct DiskOnChip));

		mtd->priv = this;
		this->virtadr = docptr;
		this->physadr = physadr;
		this->ChipID = ChipID;
		sprintf(namebuf, "with ChipID %2.2X", ChipID);

		switch(ChipID) {
		case DOC_ChipID_Doc2kTSOP:
			name="2000 TSOP";
271
			initroutine = symbol_request(DoC2k_init);
L
Linus Torvalds 已提交
272
			break;
273

L
Linus Torvalds 已提交
274 275
		case DOC_ChipID_Doc2k:
			name="2000";
276
			initroutine = symbol_request(DoC2k_init);
L
Linus Torvalds 已提交
277
			break;
278

L
Linus Torvalds 已提交
279 280 281
		case DOC_ChipID_DocMil:
			name="Millennium";
#ifdef DOC_SINGLE_DRIVER
282
			initroutine = symbol_request(DoC2k_init);
L
Linus Torvalds 已提交
283
#else
284
			initroutine = symbol_request(DoCMil_init);
L
Linus Torvalds 已提交
285 286 287 288 289 290
#endif /* DOC_SINGLE_DRIVER */
			break;

		case DOC_ChipID_DocMilPlus16:
		case DOC_ChipID_DocMilPlus32:
			name="MillenniumPlus";
291
			initroutine = symbol_request(DoCMilPlus_init);
L
Linus Torvalds 已提交
292 293 294 295 296
			break;
		}

		if (initroutine) {
			(*initroutine)(mtd);
297
			symbol_put_addr(initroutine);
L
Linus Torvalds 已提交
298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315
			return;
		}
		printk(KERN_NOTICE "Cannot find driver for DiskOnChip %s at 0x%lX\n", name, physadr);
		kfree(mtd);
	}
	iounmap(docptr);
}


/****************************************************************************
 *
 * Module stuff
 *
 ****************************************************************************/

static int __init init_doc(void)
{
	int i;
316

L
Linus Torvalds 已提交
317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337
	if (doc_config_location) {
		printk(KERN_INFO "Using configured DiskOnChip probe address 0x%lx\n", doc_config_location);
		DoC_Probe(doc_config_location);
	} else {
		for (i=0; (doc_locations[i] != 0xffffffff); i++) {
			DoC_Probe(doc_locations[i]);
		}
	}
	/* No banner message any more. Print a message if no DiskOnChip
	   found, so the user knows we at least tried. */
	if (!docfound)
		printk(KERN_INFO "No recognised DiskOnChip devices found\n");
	return -EAGAIN;
}

module_init(init_doc);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Probe code for DiskOnChip 2000 and Millennium devices");