xref: /openbmc/linux/drivers/mtd/devices/pmc551.c (revision 05bcf503)
1 /*
2  * PMC551 PCI Mezzanine Ram Device
3  *
4  * Author:
5  *	Mark Ferrell <mferrell@mvista.com>
6  *	Copyright 1999,2000 Nortel Networks
7  *
8  * License:
9  *	As part of this driver was derived from the slram.c driver it
10  *	falls under the same license, which is GNU General Public
11  *	License v2
12  *
13  * Description:
14  *	This driver is intended to support the PMC551 PCI Ram device
15  *	from Ramix Inc.  The PMC551 is a PMC Mezzanine module for
16  *	cPCI embedded systems.  The device contains a single SROM
17  *	that initially programs the V370PDC chipset onboard the
18  *	device, and various banks of DRAM/SDRAM onboard.  This driver
19  *	implements this PCI Ram device as an MTD (Memory Technology
20  *	Device) so that it can be used to hold a file system, or for
21  *	added swap space in embedded systems.  Since the memory on
22  *	this board isn't as fast as main memory we do not try to hook
23  *	it into main memory as that would simply reduce performance
24  *	on the system.  Using it as a block device allows us to use
25  *	it as high speed swap or for a high speed disk device of some
26  *	sort.  Which becomes very useful on diskless systems in the
27  *	embedded market I might add.
28  *
29  * Notes:
30  *	Due to what I assume is more buggy SROM, the 64M PMC551 I
31  *	have available claims that all 4 of its DRAM banks have 64MiB
32  *	of ram configured (making a grand total of 256MiB onboard).
33  *	This is slightly annoying since the BAR0 size reflects the
34  *	aperture size, not the dram size, and the V370PDC supplies no
35  *	other method for memory size discovery.  This problem is
36  *	mostly only relevant when compiled as a module, as the
37  *	unloading of the module with an aperture size smaller than
38  *	the ram will cause the driver to detect the onboard memory
39  *	size to be equal to the aperture size when the module is
40  *	reloaded.  Soooo, to help, the module supports an msize
41  *	option to allow the specification of the onboard memory, and
42  *	an asize option, to allow the specification of the aperture
43  *	size.  The aperture must be equal to or less then the memory
44  *	size, the driver will correct this if you screw it up.  This
45  *	problem is not relevant for compiled in drivers as compiled
46  *	in drivers only init once.
47  *
48  * Credits:
49  *	Saeed Karamooz <saeed@ramix.com> of Ramix INC. for the
50  *	initial example code of how to initialize this device and for
51  *	help with questions I had concerning operation of the device.
52  *
53  *	Most of the MTD code for this driver was originally written
54  *	for the slram.o module in the MTD drivers package which
55  *	allows the mapping of system memory into an MTD device.
56  *	Since the PMC551 memory module is accessed in the same
57  *	fashion as system memory, the slram.c code became a very nice
58  *	fit to the needs of this driver.  All we added was PCI
59  *	detection/initialization to the driver and automatically figure
60  *	out the size via the PCI detection.o, later changes by Corey
61  *	Minyard set up the card to utilize a 1M sliding apature.
62  *
63  *	Corey Minyard <minyard@nortelnetworks.com>
64  *	* Modified driver to utilize a sliding aperture instead of
65  *	 mapping all memory into kernel space which turned out to
66  *	 be very wasteful.
67  *	* Located a bug in the SROM's initialization sequence that
68  *	 made the memory unusable, added a fix to code to touch up
69  *	 the DRAM some.
70  *
71  * Bugs/FIXMEs:
72  *	* MUST fix the init function to not spin on a register
73  *	waiting for it to set .. this does not safely handle busted
74  *	devices that never reset the register correctly which will
75  *	cause the system to hang w/ a reboot being the only chance at
76  *	recover. [sort of fixed, could be better]
77  *	* Add I2C handling of the SROM so we can read the SROM's information
78  *	about the aperture size.  This should always accurately reflect the
79  *	onboard memory size.
80  *	* Comb the init routine.  It's still a bit cludgy on a few things.
81  */
82 
83 #include <linux/kernel.h>
84 #include <linux/module.h>
85 #include <asm/uaccess.h>
86 #include <linux/types.h>
87 #include <linux/init.h>
88 #include <linux/ptrace.h>
89 #include <linux/slab.h>
90 #include <linux/string.h>
91 #include <linux/timer.h>
92 #include <linux/major.h>
93 #include <linux/fs.h>
94 #include <linux/ioctl.h>
95 #include <asm/io.h>
96 #include <linux/pci.h>
97 #include <linux/mtd/mtd.h>
98 
99 #define PMC551_VERSION \
100 	"Ramix PMC551 PCI Mezzanine Ram Driver. (C) 1999,2000 Nortel Networks.\n"
101 
102 #define PCI_VENDOR_ID_V3_SEMI 0x11b0
103 #define PCI_DEVICE_ID_V3_SEMI_V370PDC 0x0200
104 
105 #define PMC551_PCI_MEM_MAP0 0x50
106 #define PMC551_PCI_MEM_MAP1 0x54
107 #define PMC551_PCI_MEM_MAP_MAP_ADDR_MASK 0x3ff00000
108 #define PMC551_PCI_MEM_MAP_APERTURE_MASK 0x000000f0
109 #define PMC551_PCI_MEM_MAP_REG_EN 0x00000002
110 #define PMC551_PCI_MEM_MAP_ENABLE 0x00000001
111 
112 #define PMC551_SDRAM_MA  0x60
113 #define PMC551_SDRAM_CMD 0x62
114 #define PMC551_DRAM_CFG  0x64
115 #define PMC551_SYS_CTRL_REG 0x78
116 
117 #define PMC551_DRAM_BLK0 0x68
118 #define PMC551_DRAM_BLK1 0x6c
119 #define PMC551_DRAM_BLK2 0x70
120 #define PMC551_DRAM_BLK3 0x74
121 #define PMC551_DRAM_BLK_GET_SIZE(x) (524288 << ((x >> 4) & 0x0f))
122 #define PMC551_DRAM_BLK_SET_COL_MUX(x, v) (((x) & ~0x00007000) | (((v) & 0x7) << 12))
123 #define PMC551_DRAM_BLK_SET_ROW_MUX(x, v) (((x) & ~0x00000f00) | (((v) & 0xf) << 8))
124 
125 struct mypriv {
126 	struct pci_dev *dev;
127 	u_char *start;
128 	u32 base_map0;
129 	u32 curr_map0;
130 	u32 asize;
131 	struct mtd_info *nextpmc551;
132 };
133 
134 static struct mtd_info *pmc551list;
135 
136 static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
137 			size_t *retlen, void **virt, resource_size_t *phys);
138 
139 static int pmc551_erase(struct mtd_info *mtd, struct erase_info *instr)
140 {
141 	struct mypriv *priv = mtd->priv;
142 	u32 soff_hi, soff_lo;	/* start address offset hi/lo */
143 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
144 	unsigned long end;
145 	u_char *ptr;
146 	size_t retlen;
147 
148 #ifdef CONFIG_MTD_PMC551_DEBUG
149 	printk(KERN_DEBUG "pmc551_erase(pos:%ld, len:%ld)\n", (long)instr->addr,
150 		(long)instr->len);
151 #endif
152 
153 	end = instr->addr + instr->len - 1;
154 	eoff_hi = end & ~(priv->asize - 1);
155 	soff_hi = instr->addr & ~(priv->asize - 1);
156 	eoff_lo = end & (priv->asize - 1);
157 	soff_lo = instr->addr & (priv->asize - 1);
158 
159 	pmc551_point(mtd, instr->addr, instr->len, &retlen,
160 		     (void **)&ptr, NULL);
161 
162 	if (soff_hi == eoff_hi || mtd->size == priv->asize) {
163 		/* The whole thing fits within one access, so just one shot
164 		   will do it. */
165 		memset(ptr, 0xff, instr->len);
166 	} else {
167 		/* We have to do multiple writes to get all the data
168 		   written. */
169 		while (soff_hi != eoff_hi) {
170 #ifdef CONFIG_MTD_PMC551_DEBUG
171 			printk(KERN_DEBUG "pmc551_erase() soff_hi: %ld, "
172 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
173 #endif
174 			memset(ptr, 0xff, priv->asize);
175 			if (soff_hi + priv->asize >= mtd->size) {
176 				goto out;
177 			}
178 			soff_hi += priv->asize;
179 			pmc551_point(mtd, (priv->base_map0 | soff_hi),
180 				     priv->asize, &retlen,
181 				     (void **)&ptr, NULL);
182 		}
183 		memset(ptr, 0xff, eoff_lo);
184 	}
185 
186       out:
187 	instr->state = MTD_ERASE_DONE;
188 #ifdef CONFIG_MTD_PMC551_DEBUG
189 	printk(KERN_DEBUG "pmc551_erase() done\n");
190 #endif
191 
192 	mtd_erase_callback(instr);
193 	return 0;
194 }
195 
196 static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
197 			size_t *retlen, void **virt, resource_size_t *phys)
198 {
199 	struct mypriv *priv = mtd->priv;
200 	u32 soff_hi;
201 	u32 soff_lo;
202 
203 #ifdef CONFIG_MTD_PMC551_DEBUG
204 	printk(KERN_DEBUG "pmc551_point(%ld, %ld)\n", (long)from, (long)len);
205 #endif
206 
207 	soff_hi = from & ~(priv->asize - 1);
208 	soff_lo = from & (priv->asize - 1);
209 
210 	/* Cheap hack optimization */
211 	if (priv->curr_map0 != from) {
212 		pci_write_config_dword(priv->dev, PMC551_PCI_MEM_MAP0,
213 					(priv->base_map0 | soff_hi));
214 		priv->curr_map0 = soff_hi;
215 	}
216 
217 	*virt = priv->start + soff_lo;
218 	*retlen = len;
219 	return 0;
220 }
221 
222 static int pmc551_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
223 {
224 #ifdef CONFIG_MTD_PMC551_DEBUG
225 	printk(KERN_DEBUG "pmc551_unpoint()\n");
226 #endif
227 	return 0;
228 }
229 
230 static int pmc551_read(struct mtd_info *mtd, loff_t from, size_t len,
231 			size_t * retlen, u_char * buf)
232 {
233 	struct mypriv *priv = mtd->priv;
234 	u32 soff_hi, soff_lo;	/* start address offset hi/lo */
235 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
236 	unsigned long end;
237 	u_char *ptr;
238 	u_char *copyto = buf;
239 
240 #ifdef CONFIG_MTD_PMC551_DEBUG
241 	printk(KERN_DEBUG "pmc551_read(pos:%ld, len:%ld) asize: %ld\n",
242 		(long)from, (long)len, (long)priv->asize);
243 #endif
244 
245 	end = from + len - 1;
246 	soff_hi = from & ~(priv->asize - 1);
247 	eoff_hi = end & ~(priv->asize - 1);
248 	soff_lo = from & (priv->asize - 1);
249 	eoff_lo = end & (priv->asize - 1);
250 
251 	pmc551_point(mtd, from, len, retlen, (void **)&ptr, NULL);
252 
253 	if (soff_hi == eoff_hi) {
254 		/* The whole thing fits within one access, so just one shot
255 		   will do it. */
256 		memcpy(copyto, ptr, len);
257 		copyto += len;
258 	} else {
259 		/* We have to do multiple writes to get all the data
260 		   written. */
261 		while (soff_hi != eoff_hi) {
262 #ifdef CONFIG_MTD_PMC551_DEBUG
263 			printk(KERN_DEBUG "pmc551_read() soff_hi: %ld, "
264 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
265 #endif
266 			memcpy(copyto, ptr, priv->asize);
267 			copyto += priv->asize;
268 			if (soff_hi + priv->asize >= mtd->size) {
269 				goto out;
270 			}
271 			soff_hi += priv->asize;
272 			pmc551_point(mtd, soff_hi, priv->asize, retlen,
273 				     (void **)&ptr, NULL);
274 		}
275 		memcpy(copyto, ptr, eoff_lo);
276 		copyto += eoff_lo;
277 	}
278 
279       out:
280 #ifdef CONFIG_MTD_PMC551_DEBUG
281 	printk(KERN_DEBUG "pmc551_read() done\n");
282 #endif
283 	*retlen = copyto - buf;
284 	return 0;
285 }
286 
287 static int pmc551_write(struct mtd_info *mtd, loff_t to, size_t len,
288 			size_t * retlen, const u_char * buf)
289 {
290 	struct mypriv *priv = mtd->priv;
291 	u32 soff_hi, soff_lo;	/* start address offset hi/lo */
292 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
293 	unsigned long end;
294 	u_char *ptr;
295 	const u_char *copyfrom = buf;
296 
297 #ifdef CONFIG_MTD_PMC551_DEBUG
298 	printk(KERN_DEBUG "pmc551_write(pos:%ld, len:%ld) asize:%ld\n",
299 		(long)to, (long)len, (long)priv->asize);
300 #endif
301 
302 	end = to + len - 1;
303 	soff_hi = to & ~(priv->asize - 1);
304 	eoff_hi = end & ~(priv->asize - 1);
305 	soff_lo = to & (priv->asize - 1);
306 	eoff_lo = end & (priv->asize - 1);
307 
308 	pmc551_point(mtd, to, len, retlen, (void **)&ptr, NULL);
309 
310 	if (soff_hi == eoff_hi) {
311 		/* The whole thing fits within one access, so just one shot
312 		   will do it. */
313 		memcpy(ptr, copyfrom, len);
314 		copyfrom += len;
315 	} else {
316 		/* We have to do multiple writes to get all the data
317 		   written. */
318 		while (soff_hi != eoff_hi) {
319 #ifdef CONFIG_MTD_PMC551_DEBUG
320 			printk(KERN_DEBUG "pmc551_write() soff_hi: %ld, "
321 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
322 #endif
323 			memcpy(ptr, copyfrom, priv->asize);
324 			copyfrom += priv->asize;
325 			if (soff_hi >= mtd->size) {
326 				goto out;
327 			}
328 			soff_hi += priv->asize;
329 			pmc551_point(mtd, soff_hi, priv->asize, retlen,
330 				     (void **)&ptr, NULL);
331 		}
332 		memcpy(ptr, copyfrom, eoff_lo);
333 		copyfrom += eoff_lo;
334 	}
335 
336       out:
337 #ifdef CONFIG_MTD_PMC551_DEBUG
338 	printk(KERN_DEBUG "pmc551_write() done\n");
339 #endif
340 	*retlen = copyfrom - buf;
341 	return 0;
342 }
343 
344 /*
345  * Fixup routines for the V370PDC
346  * PCI device ID 0x020011b0
347  *
348  * This function basically kick starts the DRAM oboard the card and gets it
349  * ready to be used.  Before this is done the device reads VERY erratic, so
350  * much that it can crash the Linux 2.2.x series kernels when a user cat's
351  * /proc/pci .. though that is mainly a kernel bug in handling the PCI DEVSEL
352  * register.  FIXME: stop spinning on registers .. must implement a timeout
353  * mechanism
354  * returns the size of the memory region found.
355  */
356 static int fixup_pmc551(struct pci_dev *dev)
357 {
358 #ifdef CONFIG_MTD_PMC551_BUGFIX
359 	u32 dram_data;
360 #endif
361 	u32 size, dcmd, cfg, dtmp;
362 	u16 cmd, tmp, i;
363 	u8 bcmd, counter;
364 
365 	/* Sanity Check */
366 	if (!dev) {
367 		return -ENODEV;
368 	}
369 
370 	/*
371 	 * Attempt to reset the card
372 	 * FIXME: Stop Spinning registers
373 	 */
374 	counter = 0;
375 	/* unlock registers */
376 	pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, 0xA5);
377 	/* read in old data */
378 	pci_read_config_byte(dev, PMC551_SYS_CTRL_REG, &bcmd);
379 	/* bang the reset line up and down for a few */
380 	for (i = 0; i < 10; i++) {
381 		counter = 0;
382 		bcmd &= ~0x80;
383 		while (counter++ < 100) {
384 			pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
385 		}
386 		counter = 0;
387 		bcmd |= 0x80;
388 		while (counter++ < 100) {
389 			pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
390 		}
391 	}
392 	bcmd |= (0x40 | 0x20);
393 	pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
394 
395 	/*
396 	 * Take care and turn off the memory on the device while we
397 	 * tweak the configurations
398 	 */
399 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
400 	tmp = cmd & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
401 	pci_write_config_word(dev, PCI_COMMAND, tmp);
402 
403 	/*
404 	 * Disable existing aperture before probing memory size
405 	 */
406 	pci_read_config_dword(dev, PMC551_PCI_MEM_MAP0, &dcmd);
407 	dtmp = (dcmd | PMC551_PCI_MEM_MAP_ENABLE | PMC551_PCI_MEM_MAP_REG_EN);
408 	pci_write_config_dword(dev, PMC551_PCI_MEM_MAP0, dtmp);
409 	/*
410 	 * Grab old BAR0 config so that we can figure out memory size
411 	 * This is another bit of kludge going on.  The reason for the
412 	 * redundancy is I am hoping to retain the original configuration
413 	 * previously assigned to the card by the BIOS or some previous
414 	 * fixup routine in the kernel.  So we read the old config into cfg,
415 	 * then write all 1's to the memory space, read back the result into
416 	 * "size", and then write back all the old config.
417 	 */
418 	pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, &cfg);
419 #ifndef CONFIG_MTD_PMC551_BUGFIX
420 	pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, ~0);
421 	pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, &size);
422 	size = (size & PCI_BASE_ADDRESS_MEM_MASK);
423 	size &= ~(size - 1);
424 	pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, cfg);
425 #else
426 	/*
427 	 * Get the size of the memory by reading all the DRAM size values
428 	 * and adding them up.
429 	 *
430 	 * KLUDGE ALERT: the boards we are using have invalid column and
431 	 * row mux values.  We fix them here, but this will break other
432 	 * memory configurations.
433 	 */
434 	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dram_data);
435 	size = PMC551_DRAM_BLK_GET_SIZE(dram_data);
436 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
437 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
438 	pci_write_config_dword(dev, PMC551_DRAM_BLK0, dram_data);
439 
440 	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dram_data);
441 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
442 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
443 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
444 	pci_write_config_dword(dev, PMC551_DRAM_BLK1, dram_data);
445 
446 	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dram_data);
447 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
448 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
449 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
450 	pci_write_config_dword(dev, PMC551_DRAM_BLK2, dram_data);
451 
452 	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dram_data);
453 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
454 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
455 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
456 	pci_write_config_dword(dev, PMC551_DRAM_BLK3, dram_data);
457 
458 	/*
459 	 * Oops .. something went wrong
460 	 */
461 	if ((size &= PCI_BASE_ADDRESS_MEM_MASK) == 0) {
462 		return -ENODEV;
463 	}
464 #endif				/* CONFIG_MTD_PMC551_BUGFIX */
465 
466 	if ((cfg & PCI_BASE_ADDRESS_SPACE) != PCI_BASE_ADDRESS_SPACE_MEMORY) {
467 		return -ENODEV;
468 	}
469 
470 	/*
471 	 * Precharge Dram
472 	 */
473 	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0400);
474 	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x00bf);
475 
476 	/*
477 	 * Wait until command has gone through
478 	 * FIXME: register spinning issue
479 	 */
480 	do {
481 		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
482 		if (counter++ > 100)
483 			break;
484 	} while ((PCI_COMMAND_IO) & cmd);
485 
486 	/*
487 	 * Turn on auto refresh
488 	 * The loop is taken directly from Ramix's example code.  I assume that
489 	 * this must be held high for some duration of time, but I can find no
490 	 * documentation refrencing the reasons why.
491 	 */
492 	for (i = 1; i <= 8; i++) {
493 		pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0df);
494 
495 		/*
496 		 * Make certain command has gone through
497 		 * FIXME: register spinning issue
498 		 */
499 		counter = 0;
500 		do {
501 			pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
502 			if (counter++ > 100)
503 				break;
504 		} while ((PCI_COMMAND_IO) & cmd);
505 	}
506 
507 	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0020);
508 	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0ff);
509 
510 	/*
511 	 * Wait until command completes
512 	 * FIXME: register spinning issue
513 	 */
514 	counter = 0;
515 	do {
516 		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
517 		if (counter++ > 100)
518 			break;
519 	} while ((PCI_COMMAND_IO) & cmd);
520 
521 	pci_read_config_dword(dev, PMC551_DRAM_CFG, &dcmd);
522 	dcmd |= 0x02000000;
523 	pci_write_config_dword(dev, PMC551_DRAM_CFG, dcmd);
524 
525 	/*
526 	 * Check to make certain fast back-to-back, if not
527 	 * then set it so
528 	 */
529 	pci_read_config_word(dev, PCI_STATUS, &cmd);
530 	if ((cmd & PCI_COMMAND_FAST_BACK) == 0) {
531 		cmd |= PCI_COMMAND_FAST_BACK;
532 		pci_write_config_word(dev, PCI_STATUS, cmd);
533 	}
534 
535 	/*
536 	 * Check to make certain the DEVSEL is set correctly, this device
537 	 * has a tendency to assert DEVSEL and TRDY when a write is performed
538 	 * to the memory when memory is read-only
539 	 */
540 	if ((cmd & PCI_STATUS_DEVSEL_MASK) != 0x0) {
541 		cmd &= ~PCI_STATUS_DEVSEL_MASK;
542 		pci_write_config_word(dev, PCI_STATUS, cmd);
543 	}
544 	/*
545 	 * Set to be prefetchable and put everything back based on old cfg.
546 	 * it's possible that the reset of the V370PDC nuked the original
547 	 * setup
548 	 */
549 	/*
550 	   cfg |= PCI_BASE_ADDRESS_MEM_PREFETCH;
551 	   pci_write_config_dword( dev, PCI_BASE_ADDRESS_0, cfg );
552 	 */
553 
554 	/*
555 	 * Turn PCI memory and I/O bus access back on
556 	 */
557 	pci_write_config_word(dev, PCI_COMMAND,
558 			      PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
559 #ifdef CONFIG_MTD_PMC551_DEBUG
560 	/*
561 	 * Some screen fun
562 	 */
563 	printk(KERN_DEBUG "pmc551: %d%sB (0x%x) of %sprefetchable memory at "
564 		"0x%llx\n", (size < 1024) ? size : (size < 1048576) ?
565 		size >> 10 : size >> 20,
566 		(size < 1024) ? "" : (size < 1048576) ? "Ki" : "Mi", size,
567 		((dcmd & (0x1 << 3)) == 0) ? "non-" : "",
568 		(unsigned long long)pci_resource_start(dev, 0));
569 
570 	/*
571 	 * Check to see the state of the memory
572 	 */
573 	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dcmd);
574 	printk(KERN_DEBUG "pmc551: DRAM_BLK0 Flags: %s,%s\n"
575 		"pmc551: DRAM_BLK0 Size: %d at %d\n"
576 		"pmc551: DRAM_BLK0 Row MUX: %d, Col MUX: %d\n",
577 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
578 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
579 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
580 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
581 		((dcmd >> 9) & 0xF));
582 
583 	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dcmd);
584 	printk(KERN_DEBUG "pmc551: DRAM_BLK1 Flags: %s,%s\n"
585 		"pmc551: DRAM_BLK1 Size: %d at %d\n"
586 		"pmc551: DRAM_BLK1 Row MUX: %d, Col MUX: %d\n",
587 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
588 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
589 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
590 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
591 		((dcmd >> 9) & 0xF));
592 
593 	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dcmd);
594 	printk(KERN_DEBUG "pmc551: DRAM_BLK2 Flags: %s,%s\n"
595 		"pmc551: DRAM_BLK2 Size: %d at %d\n"
596 		"pmc551: DRAM_BLK2 Row MUX: %d, Col MUX: %d\n",
597 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
598 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
599 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
600 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
601 		((dcmd >> 9) & 0xF));
602 
603 	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dcmd);
604 	printk(KERN_DEBUG "pmc551: DRAM_BLK3 Flags: %s,%s\n"
605 		"pmc551: DRAM_BLK3 Size: %d at %d\n"
606 		"pmc551: DRAM_BLK3 Row MUX: %d, Col MUX: %d\n",
607 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
608 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
609 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
610 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
611 		((dcmd >> 9) & 0xF));
612 
613 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
614 	printk(KERN_DEBUG "pmc551: Memory Access %s\n",
615 		(((0x1 << 1) & cmd) == 0) ? "off" : "on");
616 	printk(KERN_DEBUG "pmc551: I/O Access %s\n",
617 		(((0x1 << 0) & cmd) == 0) ? "off" : "on");
618 
619 	pci_read_config_word(dev, PCI_STATUS, &cmd);
620 	printk(KERN_DEBUG "pmc551: Devsel %s\n",
621 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x000) ? "Fast" :
622 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x200) ? "Medium" :
623 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x400) ? "Slow" : "Invalid");
624 
625 	printk(KERN_DEBUG "pmc551: %sFast Back-to-Back\n",
626 		((PCI_COMMAND_FAST_BACK & cmd) == 0) ? "Not " : "");
627 
628 	pci_read_config_byte(dev, PMC551_SYS_CTRL_REG, &bcmd);
629 	printk(KERN_DEBUG "pmc551: EEPROM is under %s control\n"
630 		"pmc551: System Control Register is %slocked to PCI access\n"
631 		"pmc551: System Control Register is %slocked to EEPROM access\n",
632 		(bcmd & 0x1) ? "software" : "hardware",
633 		(bcmd & 0x20) ? "" : "un", (bcmd & 0x40) ? "" : "un");
634 #endif
635 	return size;
636 }
637 
638 /*
639  * Kernel version specific module stuffages
640  */
641 
642 MODULE_LICENSE("GPL");
643 MODULE_AUTHOR("Mark Ferrell <mferrell@mvista.com>");
644 MODULE_DESCRIPTION(PMC551_VERSION);
645 
646 /*
647  * Stuff these outside the ifdef so as to not bust compiled in driver support
648  */
649 static int msize = 0;
650 static int asize = 0;
651 
652 module_param(msize, int, 0);
653 MODULE_PARM_DESC(msize, "memory size in MiB [1 - 1024]");
654 module_param(asize, int, 0);
655 MODULE_PARM_DESC(asize, "aperture size, must be <= memsize [1-1024]");
656 
657 /*
658  * PMC551 Card Initialization
659  */
660 static int __init init_pmc551(void)
661 {
662 	struct pci_dev *PCI_Device = NULL;
663 	struct mypriv *priv;
664 	int found = 0;
665 	struct mtd_info *mtd;
666 	int length = 0;
667 
668 	if (msize) {
669 		msize = (1 << (ffs(msize) - 1)) << 20;
670 		if (msize > (1 << 30)) {
671 			printk(KERN_NOTICE "pmc551: Invalid memory size [%d]\n",
672 				msize);
673 			return -EINVAL;
674 		}
675 	}
676 
677 	if (asize) {
678 		asize = (1 << (ffs(asize) - 1)) << 20;
679 		if (asize > (1 << 30)) {
680 			printk(KERN_NOTICE "pmc551: Invalid aperture size "
681 				"[%d]\n", asize);
682 			return -EINVAL;
683 		}
684 	}
685 
686 	printk(KERN_INFO PMC551_VERSION);
687 
688 	/*
689 	 * PCU-bus chipset probe.
690 	 */
691 	for (;;) {
692 
693 		if ((PCI_Device = pci_get_device(PCI_VENDOR_ID_V3_SEMI,
694 						  PCI_DEVICE_ID_V3_SEMI_V370PDC,
695 						  PCI_Device)) == NULL) {
696 			break;
697 		}
698 
699 		printk(KERN_NOTICE "pmc551: Found PCI V370PDC at 0x%llx\n",
700 			(unsigned long long)pci_resource_start(PCI_Device, 0));
701 
702 		/*
703 		 * The PMC551 device acts VERY weird if you don't init it
704 		 * first.  i.e. it will not correctly report devsel.  If for
705 		 * some reason the sdram is in a wrote-protected state the
706 		 * device will DEVSEL when it is written to causing problems
707 		 * with the oldproc.c driver in
708 		 * some kernels (2.2.*)
709 		 */
710 		if ((length = fixup_pmc551(PCI_Device)) <= 0) {
711 			printk(KERN_NOTICE "pmc551: Cannot init SDRAM\n");
712 			break;
713 		}
714 
715 		/*
716 		 * This is needed until the driver is capable of reading the
717 		 * onboard I2C SROM to discover the "real" memory size.
718 		 */
719 		if (msize) {
720 			length = msize;
721 			printk(KERN_NOTICE "pmc551: Using specified memory "
722 				"size 0x%x\n", length);
723 		} else {
724 			msize = length;
725 		}
726 
727 		mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
728 		if (!mtd) {
729 			printk(KERN_NOTICE "pmc551: Cannot allocate new MTD "
730 				"device.\n");
731 			break;
732 		}
733 
734 		priv = kzalloc(sizeof(struct mypriv), GFP_KERNEL);
735 		if (!priv) {
736 			printk(KERN_NOTICE "pmc551: Cannot allocate new MTD "
737 				"device.\n");
738 			kfree(mtd);
739 			break;
740 		}
741 		mtd->priv = priv;
742 		priv->dev = PCI_Device;
743 
744 		if (asize > length) {
745 			printk(KERN_NOTICE "pmc551: reducing aperture size to "
746 				"fit %dM\n", length >> 20);
747 			priv->asize = asize = length;
748 		} else if (asize == 0 || asize == length) {
749 			printk(KERN_NOTICE "pmc551: Using existing aperture "
750 				"size %dM\n", length >> 20);
751 			priv->asize = asize = length;
752 		} else {
753 			printk(KERN_NOTICE "pmc551: Using specified aperture "
754 				"size %dM\n", asize >> 20);
755 			priv->asize = asize;
756 		}
757 		priv->start = pci_iomap(PCI_Device, 0, priv->asize);
758 
759 		if (!priv->start) {
760 			printk(KERN_NOTICE "pmc551: Unable to map IO space\n");
761 			kfree(mtd->priv);
762 			kfree(mtd);
763 			break;
764 		}
765 #ifdef CONFIG_MTD_PMC551_DEBUG
766 		printk(KERN_DEBUG "pmc551: setting aperture to %d\n",
767 			ffs(priv->asize >> 20) - 1);
768 #endif
769 
770 		priv->base_map0 = (PMC551_PCI_MEM_MAP_REG_EN
771 				   | PMC551_PCI_MEM_MAP_ENABLE
772 				   | (ffs(priv->asize >> 20) - 1) << 4);
773 		priv->curr_map0 = priv->base_map0;
774 		pci_write_config_dword(priv->dev, PMC551_PCI_MEM_MAP0,
775 					priv->curr_map0);
776 
777 #ifdef CONFIG_MTD_PMC551_DEBUG
778 		printk(KERN_DEBUG "pmc551: aperture set to %d\n",
779 			(priv->base_map0 & 0xF0) >> 4);
780 #endif
781 
782 		mtd->size = msize;
783 		mtd->flags = MTD_CAP_RAM;
784 		mtd->_erase = pmc551_erase;
785 		mtd->_read = pmc551_read;
786 		mtd->_write = pmc551_write;
787 		mtd->_point = pmc551_point;
788 		mtd->_unpoint = pmc551_unpoint;
789 		mtd->type = MTD_RAM;
790 		mtd->name = "PMC551 RAM board";
791 		mtd->erasesize = 0x10000;
792 		mtd->writesize = 1;
793 		mtd->owner = THIS_MODULE;
794 
795 		if (mtd_device_register(mtd, NULL, 0)) {
796 			printk(KERN_NOTICE "pmc551: Failed to register new device\n");
797 			pci_iounmap(PCI_Device, priv->start);
798 			kfree(mtd->priv);
799 			kfree(mtd);
800 			break;
801 		}
802 
803 		/* Keep a reference as the mtd_device_register worked */
804 		pci_dev_get(PCI_Device);
805 
806 		printk(KERN_NOTICE "Registered pmc551 memory device.\n");
807 		printk(KERN_NOTICE "Mapped %dMiB of memory from 0x%p to 0x%p\n",
808 			priv->asize >> 20,
809 			priv->start, priv->start + priv->asize);
810 		printk(KERN_NOTICE "Total memory is %d%sB\n",
811 			(length < 1024) ? length :
812 			(length < 1048576) ? length >> 10 : length >> 20,
813 			(length < 1024) ? "" : (length < 1048576) ? "Ki" : "Mi");
814 		priv->nextpmc551 = pmc551list;
815 		pmc551list = mtd;
816 		found++;
817 	}
818 
819 	/* Exited early, reference left over */
820 	if (PCI_Device)
821 		pci_dev_put(PCI_Device);
822 
823 	if (!pmc551list) {
824 		printk(KERN_NOTICE "pmc551: not detected\n");
825 		return -ENODEV;
826 	} else {
827 		printk(KERN_NOTICE "pmc551: %d pmc551 devices loaded\n", found);
828 		return 0;
829 	}
830 }
831 
832 /*
833  * PMC551 Card Cleanup
834  */
835 static void __exit cleanup_pmc551(void)
836 {
837 	int found = 0;
838 	struct mtd_info *mtd;
839 	struct mypriv *priv;
840 
841 	while ((mtd = pmc551list)) {
842 		priv = mtd->priv;
843 		pmc551list = priv->nextpmc551;
844 
845 		if (priv->start) {
846 			printk(KERN_DEBUG "pmc551: unmapping %dMiB starting at "
847 				"0x%p\n", priv->asize >> 20, priv->start);
848 			pci_iounmap(priv->dev, priv->start);
849 		}
850 		pci_dev_put(priv->dev);
851 
852 		kfree(mtd->priv);
853 		mtd_device_unregister(mtd);
854 		kfree(mtd);
855 		found++;
856 	}
857 
858 	printk(KERN_NOTICE "pmc551: %d pmc551 devices unloaded\n", found);
859 }
860 
861 module_init(init_pmc551);
862 module_exit(cleanup_pmc551);
863