xref: /openbmc/linux/drivers/mtd/devices/pmc551.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * PMC551 PCI Mezzanine Ram Device
4  *
5  * Author:
6  *	Mark Ferrell <mferrell@mvista.com>
7  *	Copyright 1999,2000 Nortel Networks
8  *
9  * Description:
10  *	This driver is intended to support the PMC551 PCI Ram device
11  *	from Ramix Inc.  The PMC551 is a PMC Mezzanine module for
12  *	cPCI embedded systems.  The device contains a single SROM
13  *	that initially programs the V370PDC chipset onboard the
14  *	device, and various banks of DRAM/SDRAM onboard.  This driver
15  *	implements this PCI Ram device as an MTD (Memory Technology
16  *	Device) so that it can be used to hold a file system, or for
17  *	added swap space in embedded systems.  Since the memory on
18  *	this board isn't as fast as main memory we do not try to hook
19  *	it into main memory as that would simply reduce performance
20  *	on the system.  Using it as a block device allows us to use
21  *	it as high speed swap or for a high speed disk device of some
22  *	sort.  Which becomes very useful on diskless systems in the
23  *	embedded market I might add.
24  *
25  * Notes:
26  *	Due to what I assume is more buggy SROM, the 64M PMC551 I
27  *	have available claims that all 4 of its DRAM banks have 64MiB
28  *	of ram configured (making a grand total of 256MiB onboard).
29  *	This is slightly annoying since the BAR0 size reflects the
30  *	aperture size, not the dram size, and the V370PDC supplies no
31  *	other method for memory size discovery.  This problem is
32  *	mostly only relevant when compiled as a module, as the
33  *	unloading of the module with an aperture size smaller than
34  *	the ram will cause the driver to detect the onboard memory
35  *	size to be equal to the aperture size when the module is
36  *	reloaded.  Soooo, to help, the module supports an msize
37  *	option to allow the specification of the onboard memory, and
38  *	an asize option, to allow the specification of the aperture
39  *	size.  The aperture must be equal to or less then the memory
40  *	size, the driver will correct this if you screw it up.  This
41  *	problem is not relevant for compiled in drivers as compiled
42  *	in drivers only init once.
43  *
44  * Credits:
45  *	Saeed Karamooz <saeed@ramix.com> of Ramix INC. for the
46  *	initial example code of how to initialize this device and for
47  *	help with questions I had concerning operation of the device.
48  *
49  *	Most of the MTD code for this driver was originally written
50  *	for the slram.o module in the MTD drivers package which
51  *	allows the mapping of system memory into an MTD device.
52  *	Since the PMC551 memory module is accessed in the same
53  *	fashion as system memory, the slram.c code became a very nice
54  *	fit to the needs of this driver.  All we added was PCI
55  *	detection/initialization to the driver and automatically figure
56  *	out the size via the PCI detection.o, later changes by Corey
57  *	Minyard set up the card to utilize a 1M sliding apature.
58  *
59  *	Corey Minyard <minyard@nortelnetworks.com>
60  *	* Modified driver to utilize a sliding aperture instead of
61  *	 mapping all memory into kernel space which turned out to
62  *	 be very wasteful.
63  *	* Located a bug in the SROM's initialization sequence that
64  *	 made the memory unusable, added a fix to code to touch up
65  *	 the DRAM some.
66  *
67  * Bugs/FIXMEs:
68  *	* MUST fix the init function to not spin on a register
69  *	waiting for it to set .. this does not safely handle busted
70  *	devices that never reset the register correctly which will
71  *	cause the system to hang w/ a reboot being the only chance at
72  *	recover. [sort of fixed, could be better]
73  *	* Add I2C handling of the SROM so we can read the SROM's information
74  *	about the aperture size.  This should always accurately reflect the
75  *	onboard memory size.
76  *	* Comb the init routine.  It's still a bit cludgy on a few things.
77  */
78 
79 #include <linux/kernel.h>
80 #include <linux/module.h>
81 #include <linux/uaccess.h>
82 #include <linux/types.h>
83 #include <linux/init.h>
84 #include <linux/ptrace.h>
85 #include <linux/slab.h>
86 #include <linux/string.h>
87 #include <linux/timer.h>
88 #include <linux/major.h>
89 #include <linux/fs.h>
90 #include <linux/ioctl.h>
91 #include <asm/io.h>
92 #include <linux/pci.h>
93 #include <linux/mtd/mtd.h>
94 
95 #define PMC551_VERSION \
96 	"Ramix PMC551 PCI Mezzanine Ram Driver. (C) 1999,2000 Nortel Networks.\n"
97 
98 #define PCI_VENDOR_ID_V3_SEMI 0x11b0
99 #define PCI_DEVICE_ID_V3_SEMI_V370PDC 0x0200
100 
101 #define PMC551_PCI_MEM_MAP0 0x50
102 #define PMC551_PCI_MEM_MAP1 0x54
103 #define PMC551_PCI_MEM_MAP_MAP_ADDR_MASK 0x3ff00000
104 #define PMC551_PCI_MEM_MAP_APERTURE_MASK 0x000000f0
105 #define PMC551_PCI_MEM_MAP_REG_EN 0x00000002
106 #define PMC551_PCI_MEM_MAP_ENABLE 0x00000001
107 
108 #define PMC551_SDRAM_MA  0x60
109 #define PMC551_SDRAM_CMD 0x62
110 #define PMC551_DRAM_CFG  0x64
111 #define PMC551_SYS_CTRL_REG 0x78
112 
113 #define PMC551_DRAM_BLK0 0x68
114 #define PMC551_DRAM_BLK1 0x6c
115 #define PMC551_DRAM_BLK2 0x70
116 #define PMC551_DRAM_BLK3 0x74
117 #define PMC551_DRAM_BLK_GET_SIZE(x) (524288 << ((x >> 4) & 0x0f))
118 #define PMC551_DRAM_BLK_SET_COL_MUX(x, v) (((x) & ~0x00007000) | (((v) & 0x7) << 12))
119 #define PMC551_DRAM_BLK_SET_ROW_MUX(x, v) (((x) & ~0x00000f00) | (((v) & 0xf) << 8))
120 
121 struct mypriv {
122 	struct pci_dev *dev;
123 	u_char *start;
124 	u32 base_map0;
125 	u32 curr_map0;
126 	u32 asize;
127 	struct mtd_info *nextpmc551;
128 };
129 
130 static struct mtd_info *pmc551list;
131 
132 static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
133 			size_t *retlen, void **virt, resource_size_t *phys);
134 
135 static int pmc551_erase(struct mtd_info *mtd, struct erase_info *instr)
136 {
137 	struct mypriv *priv = mtd->priv;
138 	u32 soff_hi;		/* start address offset hi */
139 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
140 	unsigned long end;
141 	u_char *ptr;
142 	size_t retlen;
143 
144 #ifdef CONFIG_MTD_PMC551_DEBUG
145 	printk(KERN_DEBUG "pmc551_erase(pos:%ld, len:%ld)\n", (long)instr->addr,
146 		(long)instr->len);
147 #endif
148 
149 	end = instr->addr + instr->len - 1;
150 	eoff_hi = end & ~(priv->asize - 1);
151 	soff_hi = instr->addr & ~(priv->asize - 1);
152 	eoff_lo = end & (priv->asize - 1);
153 
154 	pmc551_point(mtd, instr->addr, instr->len, &retlen,
155 		     (void **)&ptr, NULL);
156 
157 	if (soff_hi == eoff_hi || mtd->size == priv->asize) {
158 		/* The whole thing fits within one access, so just one shot
159 		   will do it. */
160 		memset(ptr, 0xff, instr->len);
161 	} else {
162 		/* We have to do multiple writes to get all the data
163 		   written. */
164 		while (soff_hi != eoff_hi) {
165 #ifdef CONFIG_MTD_PMC551_DEBUG
166 			printk(KERN_DEBUG "pmc551_erase() soff_hi: %ld, "
167 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
168 #endif
169 			memset(ptr, 0xff, priv->asize);
170 			if (soff_hi + priv->asize >= mtd->size) {
171 				goto out;
172 			}
173 			soff_hi += priv->asize;
174 			pmc551_point(mtd, (priv->base_map0 | soff_hi),
175 				     priv->asize, &retlen,
176 				     (void **)&ptr, NULL);
177 		}
178 		memset(ptr, 0xff, eoff_lo);
179 	}
180 
181       out:
182 #ifdef CONFIG_MTD_PMC551_DEBUG
183 	printk(KERN_DEBUG "pmc551_erase() done\n");
184 #endif
185 
186 	return 0;
187 }
188 
189 static int pmc551_point(struct mtd_info *mtd, loff_t from, size_t len,
190 			size_t *retlen, void **virt, resource_size_t *phys)
191 {
192 	struct mypriv *priv = mtd->priv;
193 	u32 soff_hi;
194 	u32 soff_lo;
195 
196 #ifdef CONFIG_MTD_PMC551_DEBUG
197 	printk(KERN_DEBUG "pmc551_point(%ld, %ld)\n", (long)from, (long)len);
198 #endif
199 
200 	soff_hi = from & ~(priv->asize - 1);
201 	soff_lo = from & (priv->asize - 1);
202 
203 	/* Cheap hack optimization */
204 	if (priv->curr_map0 != from) {
205 		pci_write_config_dword(priv->dev, PMC551_PCI_MEM_MAP0,
206 					(priv->base_map0 | soff_hi));
207 		priv->curr_map0 = soff_hi;
208 	}
209 
210 	*virt = priv->start + soff_lo;
211 	*retlen = len;
212 	return 0;
213 }
214 
215 static int pmc551_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
216 {
217 #ifdef CONFIG_MTD_PMC551_DEBUG
218 	printk(KERN_DEBUG "pmc551_unpoint()\n");
219 #endif
220 	return 0;
221 }
222 
223 static int pmc551_read(struct mtd_info *mtd, loff_t from, size_t len,
224 			size_t * retlen, u_char * buf)
225 {
226 	struct mypriv *priv = mtd->priv;
227 	u32 soff_hi;		/* start address offset hi */
228 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
229 	unsigned long end;
230 	u_char *ptr;
231 	u_char *copyto = buf;
232 
233 #ifdef CONFIG_MTD_PMC551_DEBUG
234 	printk(KERN_DEBUG "pmc551_read(pos:%ld, len:%ld) asize: %ld\n",
235 		(long)from, (long)len, (long)priv->asize);
236 #endif
237 
238 	end = from + len - 1;
239 	soff_hi = from & ~(priv->asize - 1);
240 	eoff_hi = end & ~(priv->asize - 1);
241 	eoff_lo = end & (priv->asize - 1);
242 
243 	pmc551_point(mtd, from, len, retlen, (void **)&ptr, NULL);
244 
245 	if (soff_hi == eoff_hi) {
246 		/* The whole thing fits within one access, so just one shot
247 		   will do it. */
248 		memcpy(copyto, ptr, len);
249 		copyto += len;
250 	} else {
251 		/* We have to do multiple writes to get all the data
252 		   written. */
253 		while (soff_hi != eoff_hi) {
254 #ifdef CONFIG_MTD_PMC551_DEBUG
255 			printk(KERN_DEBUG "pmc551_read() soff_hi: %ld, "
256 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
257 #endif
258 			memcpy(copyto, ptr, priv->asize);
259 			copyto += priv->asize;
260 			if (soff_hi + priv->asize >= mtd->size) {
261 				goto out;
262 			}
263 			soff_hi += priv->asize;
264 			pmc551_point(mtd, soff_hi, priv->asize, retlen,
265 				     (void **)&ptr, NULL);
266 		}
267 		memcpy(copyto, ptr, eoff_lo);
268 		copyto += eoff_lo;
269 	}
270 
271       out:
272 #ifdef CONFIG_MTD_PMC551_DEBUG
273 	printk(KERN_DEBUG "pmc551_read() done\n");
274 #endif
275 	*retlen = copyto - buf;
276 	return 0;
277 }
278 
279 static int pmc551_write(struct mtd_info *mtd, loff_t to, size_t len,
280 			size_t * retlen, const u_char * buf)
281 {
282 	struct mypriv *priv = mtd->priv;
283 	u32 soff_hi;		/* start address offset hi */
284 	u32 eoff_hi, eoff_lo;	/* end address offset hi/lo */
285 	unsigned long end;
286 	u_char *ptr;
287 	const u_char *copyfrom = buf;
288 
289 #ifdef CONFIG_MTD_PMC551_DEBUG
290 	printk(KERN_DEBUG "pmc551_write(pos:%ld, len:%ld) asize:%ld\n",
291 		(long)to, (long)len, (long)priv->asize);
292 #endif
293 
294 	end = to + len - 1;
295 	soff_hi = to & ~(priv->asize - 1);
296 	eoff_hi = end & ~(priv->asize - 1);
297 	eoff_lo = end & (priv->asize - 1);
298 
299 	pmc551_point(mtd, to, len, retlen, (void **)&ptr, NULL);
300 
301 	if (soff_hi == eoff_hi) {
302 		/* The whole thing fits within one access, so just one shot
303 		   will do it. */
304 		memcpy(ptr, copyfrom, len);
305 		copyfrom += len;
306 	} else {
307 		/* We have to do multiple writes to get all the data
308 		   written. */
309 		while (soff_hi != eoff_hi) {
310 #ifdef CONFIG_MTD_PMC551_DEBUG
311 			printk(KERN_DEBUG "pmc551_write() soff_hi: %ld, "
312 				"eoff_hi: %ld\n", (long)soff_hi, (long)eoff_hi);
313 #endif
314 			memcpy(ptr, copyfrom, priv->asize);
315 			copyfrom += priv->asize;
316 			if (soff_hi >= mtd->size) {
317 				goto out;
318 			}
319 			soff_hi += priv->asize;
320 			pmc551_point(mtd, soff_hi, priv->asize, retlen,
321 				     (void **)&ptr, NULL);
322 		}
323 		memcpy(ptr, copyfrom, eoff_lo);
324 		copyfrom += eoff_lo;
325 	}
326 
327       out:
328 #ifdef CONFIG_MTD_PMC551_DEBUG
329 	printk(KERN_DEBUG "pmc551_write() done\n");
330 #endif
331 	*retlen = copyfrom - buf;
332 	return 0;
333 }
334 
335 /*
336  * Fixup routines for the V370PDC
337  * PCI device ID 0x020011b0
338  *
339  * This function basically kick starts the DRAM oboard the card and gets it
340  * ready to be used.  Before this is done the device reads VERY erratic, so
341  * much that it can crash the Linux 2.2.x series kernels when a user cat's
342  * /proc/pci .. though that is mainly a kernel bug in handling the PCI DEVSEL
343  * register.  FIXME: stop spinning on registers .. must implement a timeout
344  * mechanism
345  * returns the size of the memory region found.
346  */
347 static int __init fixup_pmc551(struct pci_dev *dev)
348 {
349 #ifdef CONFIG_MTD_PMC551_BUGFIX
350 	u32 dram_data;
351 #endif
352 	u32 size, dcmd, cfg, dtmp;
353 	u16 cmd, tmp, i;
354 	u8 bcmd, counter;
355 
356 	/* Sanity Check */
357 	if (!dev) {
358 		return -ENODEV;
359 	}
360 
361 	/*
362 	 * Attempt to reset the card
363 	 * FIXME: Stop Spinning registers
364 	 */
365 	counter = 0;
366 	/* unlock registers */
367 	pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, 0xA5);
368 	/* read in old data */
369 	pci_read_config_byte(dev, PMC551_SYS_CTRL_REG, &bcmd);
370 	/* bang the reset line up and down for a few */
371 	for (i = 0; i < 10; i++) {
372 		counter = 0;
373 		bcmd &= ~0x80;
374 		while (counter++ < 100) {
375 			pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
376 		}
377 		counter = 0;
378 		bcmd |= 0x80;
379 		while (counter++ < 100) {
380 			pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
381 		}
382 	}
383 	bcmd |= (0x40 | 0x20);
384 	pci_write_config_byte(dev, PMC551_SYS_CTRL_REG, bcmd);
385 
386 	/*
387 	 * Take care and turn off the memory on the device while we
388 	 * tweak the configurations
389 	 */
390 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
391 	tmp = cmd & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
392 	pci_write_config_word(dev, PCI_COMMAND, tmp);
393 
394 	/*
395 	 * Disable existing aperture before probing memory size
396 	 */
397 	pci_read_config_dword(dev, PMC551_PCI_MEM_MAP0, &dcmd);
398 	dtmp = (dcmd | PMC551_PCI_MEM_MAP_ENABLE | PMC551_PCI_MEM_MAP_REG_EN);
399 	pci_write_config_dword(dev, PMC551_PCI_MEM_MAP0, dtmp);
400 	/*
401 	 * Grab old BAR0 config so that we can figure out memory size
402 	 * This is another bit of kludge going on.  The reason for the
403 	 * redundancy is I am hoping to retain the original configuration
404 	 * previously assigned to the card by the BIOS or some previous
405 	 * fixup routine in the kernel.  So we read the old config into cfg,
406 	 * then write all 1's to the memory space, read back the result into
407 	 * "size", and then write back all the old config.
408 	 */
409 	pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, &cfg);
410 #ifndef CONFIG_MTD_PMC551_BUGFIX
411 	pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, ~0);
412 	pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, &size);
413 	size = (size & PCI_BASE_ADDRESS_MEM_MASK);
414 	size &= ~(size - 1);
415 	pci_write_config_dword(dev, PCI_BASE_ADDRESS_0, cfg);
416 #else
417 	/*
418 	 * Get the size of the memory by reading all the DRAM size values
419 	 * and adding them up.
420 	 *
421 	 * KLUDGE ALERT: the boards we are using have invalid column and
422 	 * row mux values.  We fix them here, but this will break other
423 	 * memory configurations.
424 	 */
425 	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dram_data);
426 	size = PMC551_DRAM_BLK_GET_SIZE(dram_data);
427 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
428 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
429 	pci_write_config_dword(dev, PMC551_DRAM_BLK0, dram_data);
430 
431 	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dram_data);
432 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
433 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
434 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
435 	pci_write_config_dword(dev, PMC551_DRAM_BLK1, dram_data);
436 
437 	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dram_data);
438 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
439 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
440 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
441 	pci_write_config_dword(dev, PMC551_DRAM_BLK2, dram_data);
442 
443 	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dram_data);
444 	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
445 	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
446 	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
447 	pci_write_config_dword(dev, PMC551_DRAM_BLK3, dram_data);
448 
449 	/*
450 	 * Oops .. something went wrong
451 	 */
452 	if ((size &= PCI_BASE_ADDRESS_MEM_MASK) == 0) {
453 		return -ENODEV;
454 	}
455 #endif				/* CONFIG_MTD_PMC551_BUGFIX */
456 
457 	if ((cfg & PCI_BASE_ADDRESS_SPACE) != PCI_BASE_ADDRESS_SPACE_MEMORY) {
458 		return -ENODEV;
459 	}
460 
461 	/*
462 	 * Precharge Dram
463 	 */
464 	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0400);
465 	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x00bf);
466 
467 	/*
468 	 * Wait until command has gone through
469 	 * FIXME: register spinning issue
470 	 */
471 	do {
472 		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
473 		if (counter++ > 100)
474 			break;
475 	} while ((PCI_COMMAND_IO) & cmd);
476 
477 	/*
478 	 * Turn on auto refresh
479 	 * The loop is taken directly from Ramix's example code.  I assume that
480 	 * this must be held high for some duration of time, but I can find no
481 	 * documentation refrencing the reasons why.
482 	 */
483 	for (i = 1; i <= 8; i++) {
484 		pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0df);
485 
486 		/*
487 		 * Make certain command has gone through
488 		 * FIXME: register spinning issue
489 		 */
490 		counter = 0;
491 		do {
492 			pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
493 			if (counter++ > 100)
494 				break;
495 		} while ((PCI_COMMAND_IO) & cmd);
496 	}
497 
498 	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0020);
499 	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0ff);
500 
501 	/*
502 	 * Wait until command completes
503 	 * FIXME: register spinning issue
504 	 */
505 	counter = 0;
506 	do {
507 		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
508 		if (counter++ > 100)
509 			break;
510 	} while ((PCI_COMMAND_IO) & cmd);
511 
512 	pci_read_config_dword(dev, PMC551_DRAM_CFG, &dcmd);
513 	dcmd |= 0x02000000;
514 	pci_write_config_dword(dev, PMC551_DRAM_CFG, dcmd);
515 
516 	/*
517 	 * Check to make certain fast back-to-back, if not
518 	 * then set it so
519 	 */
520 	pci_read_config_word(dev, PCI_STATUS, &cmd);
521 	if ((cmd & PCI_COMMAND_FAST_BACK) == 0) {
522 		cmd |= PCI_COMMAND_FAST_BACK;
523 		pci_write_config_word(dev, PCI_STATUS, cmd);
524 	}
525 
526 	/*
527 	 * Check to make certain the DEVSEL is set correctly, this device
528 	 * has a tendency to assert DEVSEL and TRDY when a write is performed
529 	 * to the memory when memory is read-only
530 	 */
531 	if ((cmd & PCI_STATUS_DEVSEL_MASK) != 0x0) {
532 		cmd &= ~PCI_STATUS_DEVSEL_MASK;
533 		pci_write_config_word(dev, PCI_STATUS, cmd);
534 	}
535 	/*
536 	 * Set to be prefetchable and put everything back based on old cfg.
537 	 * it's possible that the reset of the V370PDC nuked the original
538 	 * setup
539 	 */
540 	/*
541 	   cfg |= PCI_BASE_ADDRESS_MEM_PREFETCH;
542 	   pci_write_config_dword( dev, PCI_BASE_ADDRESS_0, cfg );
543 	 */
544 
545 	/*
546 	 * Turn PCI memory and I/O bus access back on
547 	 */
548 	pci_write_config_word(dev, PCI_COMMAND,
549 			      PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
550 #ifdef CONFIG_MTD_PMC551_DEBUG
551 	/*
552 	 * Some screen fun
553 	 */
554 	printk(KERN_DEBUG "pmc551: %d%sB (0x%x) of %sprefetchable memory at "
555 		"0x%llx\n", (size < 1024) ? size : (size < 1048576) ?
556 		size >> 10 : size >> 20,
557 		(size < 1024) ? "" : (size < 1048576) ? "Ki" : "Mi", size,
558 		((dcmd & (0x1 << 3)) == 0) ? "non-" : "",
559 		(unsigned long long)pci_resource_start(dev, 0));
560 
561 	/*
562 	 * Check to see the state of the memory
563 	 */
564 	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dcmd);
565 	printk(KERN_DEBUG "pmc551: DRAM_BLK0 Flags: %s,%s\n"
566 		"pmc551: DRAM_BLK0 Size: %d at %d\n"
567 		"pmc551: DRAM_BLK0 Row MUX: %d, Col MUX: %d\n",
568 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
569 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
570 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
571 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
572 		((dcmd >> 9) & 0xF));
573 
574 	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dcmd);
575 	printk(KERN_DEBUG "pmc551: DRAM_BLK1 Flags: %s,%s\n"
576 		"pmc551: DRAM_BLK1 Size: %d at %d\n"
577 		"pmc551: DRAM_BLK1 Row MUX: %d, Col MUX: %d\n",
578 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
579 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
580 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
581 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
582 		((dcmd >> 9) & 0xF));
583 
584 	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dcmd);
585 	printk(KERN_DEBUG "pmc551: DRAM_BLK2 Flags: %s,%s\n"
586 		"pmc551: DRAM_BLK2 Size: %d at %d\n"
587 		"pmc551: DRAM_BLK2 Row MUX: %d, Col MUX: %d\n",
588 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
589 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
590 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
591 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
592 		((dcmd >> 9) & 0xF));
593 
594 	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dcmd);
595 	printk(KERN_DEBUG "pmc551: DRAM_BLK3 Flags: %s,%s\n"
596 		"pmc551: DRAM_BLK3 Size: %d at %d\n"
597 		"pmc551: DRAM_BLK3 Row MUX: %d, Col MUX: %d\n",
598 		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
599 		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
600 		PMC551_DRAM_BLK_GET_SIZE(dcmd),
601 		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
602 		((dcmd >> 9) & 0xF));
603 
604 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
605 	printk(KERN_DEBUG "pmc551: Memory Access %s\n",
606 		(((0x1 << 1) & cmd) == 0) ? "off" : "on");
607 	printk(KERN_DEBUG "pmc551: I/O Access %s\n",
608 		(((0x1 << 0) & cmd) == 0) ? "off" : "on");
609 
610 	pci_read_config_word(dev, PCI_STATUS, &cmd);
611 	printk(KERN_DEBUG "pmc551: Devsel %s\n",
612 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x000) ? "Fast" :
613 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x200) ? "Medium" :
614 		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x400) ? "Slow" : "Invalid");
615 
616 	printk(KERN_DEBUG "pmc551: %sFast Back-to-Back\n",
617 		((PCI_COMMAND_FAST_BACK & cmd) == 0) ? "Not " : "");
618 
619 	pci_read_config_byte(dev, PMC551_SYS_CTRL_REG, &bcmd);
620 	printk(KERN_DEBUG "pmc551: EEPROM is under %s control\n"
621 		"pmc551: System Control Register is %slocked to PCI access\n"
622 		"pmc551: System Control Register is %slocked to EEPROM access\n",
623 		(bcmd & 0x1) ? "software" : "hardware",
624 		(bcmd & 0x20) ? "" : "un", (bcmd & 0x40) ? "" : "un");
625 #endif
626 	return size;
627 }
628 
629 /*
630  * Kernel version specific module stuffages
631  */
632 
633 MODULE_LICENSE("GPL");
634 MODULE_AUTHOR("Mark Ferrell <mferrell@mvista.com>");
635 MODULE_DESCRIPTION(PMC551_VERSION);
636 
637 /*
638  * Stuff these outside the ifdef so as to not bust compiled in driver support
639  */
640 static int msize = 0;
641 static int asize = 0;
642 
643 module_param(msize, int, 0);
644 MODULE_PARM_DESC(msize, "memory size in MiB [1 - 1024]");
645 module_param(asize, int, 0);
646 MODULE_PARM_DESC(asize, "aperture size, must be <= memsize [1-1024]");
647 
648 /*
649  * PMC551 Card Initialization
650  */
651 static int __init init_pmc551(void)
652 {
653 	struct pci_dev *PCI_Device = NULL;
654 	struct mypriv *priv;
655 	int found = 0;
656 	struct mtd_info *mtd;
657 	int length = 0;
658 
659 	if (msize) {
660 		msize = (1 << (ffs(msize) - 1)) << 20;
661 		if (msize > (1 << 30)) {
662 			printk(KERN_NOTICE "pmc551: Invalid memory size [%d]\n",
663 				msize);
664 			return -EINVAL;
665 		}
666 	}
667 
668 	if (asize) {
669 		asize = (1 << (ffs(asize) - 1)) << 20;
670 		if (asize > (1 << 30)) {
671 			printk(KERN_NOTICE "pmc551: Invalid aperture size "
672 				"[%d]\n", asize);
673 			return -EINVAL;
674 		}
675 	}
676 
677 	printk(KERN_INFO PMC551_VERSION);
678 
679 	/*
680 	 * PCU-bus chipset probe.
681 	 */
682 	for (;;) {
683 
684 		if ((PCI_Device = pci_get_device(PCI_VENDOR_ID_V3_SEMI,
685 						  PCI_DEVICE_ID_V3_SEMI_V370PDC,
686 						  PCI_Device)) == NULL) {
687 			break;
688 		}
689 
690 		printk(KERN_NOTICE "pmc551: Found PCI V370PDC at 0x%llx\n",
691 			(unsigned long long)pci_resource_start(PCI_Device, 0));
692 
693 		/*
694 		 * The PMC551 device acts VERY weird if you don't init it
695 		 * first.  i.e. it will not correctly report devsel.  If for
696 		 * some reason the sdram is in a wrote-protected state the
697 		 * device will DEVSEL when it is written to causing problems
698 		 * with the oldproc.c driver in
699 		 * some kernels (2.2.*)
700 		 */
701 		if ((length = fixup_pmc551(PCI_Device)) <= 0) {
702 			printk(KERN_NOTICE "pmc551: Cannot init SDRAM\n");
703 			break;
704 		}
705 
706 		/*
707 		 * This is needed until the driver is capable of reading the
708 		 * onboard I2C SROM to discover the "real" memory size.
709 		 */
710 		if (msize) {
711 			length = msize;
712 			printk(KERN_NOTICE "pmc551: Using specified memory "
713 				"size 0x%x\n", length);
714 		} else {
715 			msize = length;
716 		}
717 
718 		mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
719 		if (!mtd)
720 			break;
721 
722 		priv = kzalloc(sizeof(struct mypriv), GFP_KERNEL);
723 		if (!priv) {
724 			kfree(mtd);
725 			break;
726 		}
727 		mtd->priv = priv;
728 		priv->dev = PCI_Device;
729 
730 		if (asize > length) {
731 			printk(KERN_NOTICE "pmc551: reducing aperture size to "
732 				"fit %dM\n", length >> 20);
733 			priv->asize = asize = length;
734 		} else if (asize == 0 || asize == length) {
735 			printk(KERN_NOTICE "pmc551: Using existing aperture "
736 				"size %dM\n", length >> 20);
737 			priv->asize = asize = length;
738 		} else {
739 			printk(KERN_NOTICE "pmc551: Using specified aperture "
740 				"size %dM\n", asize >> 20);
741 			priv->asize = asize;
742 		}
743 		priv->start = pci_iomap(PCI_Device, 0, priv->asize);
744 
745 		if (!priv->start) {
746 			printk(KERN_NOTICE "pmc551: Unable to map IO space\n");
747 			kfree(mtd->priv);
748 			kfree(mtd);
749 			break;
750 		}
751 #ifdef CONFIG_MTD_PMC551_DEBUG
752 		printk(KERN_DEBUG "pmc551: setting aperture to %d\n",
753 			ffs(priv->asize >> 20) - 1);
754 #endif
755 
756 		priv->base_map0 = (PMC551_PCI_MEM_MAP_REG_EN
757 				   | PMC551_PCI_MEM_MAP_ENABLE
758 				   | (ffs(priv->asize >> 20) - 1) << 4);
759 		priv->curr_map0 = priv->base_map0;
760 		pci_write_config_dword(priv->dev, PMC551_PCI_MEM_MAP0,
761 					priv->curr_map0);
762 
763 #ifdef CONFIG_MTD_PMC551_DEBUG
764 		printk(KERN_DEBUG "pmc551: aperture set to %d\n",
765 			(priv->base_map0 & 0xF0) >> 4);
766 #endif
767 
768 		mtd->size = msize;
769 		mtd->flags = MTD_CAP_RAM;
770 		mtd->_erase = pmc551_erase;
771 		mtd->_read = pmc551_read;
772 		mtd->_write = pmc551_write;
773 		mtd->_point = pmc551_point;
774 		mtd->_unpoint = pmc551_unpoint;
775 		mtd->type = MTD_RAM;
776 		mtd->name = "PMC551 RAM board";
777 		mtd->erasesize = 0x10000;
778 		mtd->writesize = 1;
779 		mtd->owner = THIS_MODULE;
780 
781 		if (mtd_device_register(mtd, NULL, 0)) {
782 			printk(KERN_NOTICE "pmc551: Failed to register new device\n");
783 			pci_iounmap(PCI_Device, priv->start);
784 			kfree(mtd->priv);
785 			kfree(mtd);
786 			break;
787 		}
788 
789 		/* Keep a reference as the mtd_device_register worked */
790 		pci_dev_get(PCI_Device);
791 
792 		printk(KERN_NOTICE "Registered pmc551 memory device.\n");
793 		printk(KERN_NOTICE "Mapped %dMiB of memory from 0x%p to 0x%p\n",
794 			priv->asize >> 20,
795 			priv->start, priv->start + priv->asize);
796 		printk(KERN_NOTICE "Total memory is %d%sB\n",
797 			(length < 1024) ? length :
798 			(length < 1048576) ? length >> 10 : length >> 20,
799 			(length < 1024) ? "" : (length < 1048576) ? "Ki" : "Mi");
800 		priv->nextpmc551 = pmc551list;
801 		pmc551list = mtd;
802 		found++;
803 	}
804 
805 	/* Exited early, reference left over */
806 	pci_dev_put(PCI_Device);
807 
808 	if (!pmc551list) {
809 		printk(KERN_NOTICE "pmc551: not detected\n");
810 		return -ENODEV;
811 	} else {
812 		printk(KERN_NOTICE "pmc551: %d pmc551 devices loaded\n", found);
813 		return 0;
814 	}
815 }
816 
817 /*
818  * PMC551 Card Cleanup
819  */
820 static void __exit cleanup_pmc551(void)
821 {
822 	int found = 0;
823 	struct mtd_info *mtd;
824 	struct mypriv *priv;
825 
826 	while ((mtd = pmc551list)) {
827 		priv = mtd->priv;
828 		pmc551list = priv->nextpmc551;
829 
830 		if (priv->start) {
831 			printk(KERN_DEBUG "pmc551: unmapping %dMiB starting at "
832 				"0x%p\n", priv->asize >> 20, priv->start);
833 			pci_iounmap(priv->dev, priv->start);
834 		}
835 		pci_dev_put(priv->dev);
836 
837 		kfree(mtd->priv);
838 		mtd_device_unregister(mtd);
839 		kfree(mtd);
840 		found++;
841 	}
842 
843 	printk(KERN_NOTICE "pmc551: %d pmc551 devices unloaded\n", found);
844 }
845 
846 module_init(init_pmc551);
847 module_exit(cleanup_pmc551);
848