1 /*
2  * Compaq Hot Plug Controller Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  *
8  * All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or (at
13  * your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
18  * NON INFRINGEMENT.  See the GNU General Public License for more
19  * details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  *
25  * Send feedback to <greg@kroah.com>
26  *
27  */
28 
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/types.h>
32 #include <linux/proc_fs.h>
33 #include <linux/slab.h>
34 #include <linux/workqueue.h>
35 #include <linux/pci.h>
36 #include <linux/pci_hotplug.h>
37 #include <linux/uaccess.h>
38 #include "cpqphp.h"
39 #include "cpqphp_nvram.h"
40 
41 
42 #define ROM_INT15_PHY_ADDR		0x0FF859
43 #define READ_EV				0xD8A4
44 #define WRITE_EV			0xD8A5
45 
46 struct register_foo {
47 	union {
48 		unsigned long lword;		/* eax */
49 		unsigned short word;		/* ax */
50 
51 		struct {
52 			unsigned char low;	/* al */
53 			unsigned char high;	/* ah */
54 		} byte;
55 	} data;
56 
57 	unsigned char opcode;	/* see below */
58 	unsigned long length;	/* if the reg. is a pointer, how much data */
59 } __attribute__ ((packed));
60 
61 struct all_reg {
62 	struct register_foo eax_reg;
63 	struct register_foo ebx_reg;
64 	struct register_foo ecx_reg;
65 	struct register_foo edx_reg;
66 	struct register_foo edi_reg;
67 	struct register_foo esi_reg;
68 	struct register_foo eflags_reg;
69 } __attribute__ ((packed));
70 
71 
72 struct ev_hrt_header {
73 	u8 Version;
74 	u8 num_of_ctrl;
75 	u8 next;
76 };
77 
78 struct ev_hrt_ctrl {
79 	u8 bus;
80 	u8 device;
81 	u8 function;
82 	u8 mem_avail;
83 	u8 p_mem_avail;
84 	u8 io_avail;
85 	u8 bus_avail;
86 	u8 next;
87 };
88 
89 
90 static u8 evbuffer_init;
91 static u8 evbuffer_length;
92 static u8 evbuffer[1024];
93 
94 static void __iomem *compaq_int15_entry_point;
95 
96 /* lock for ordering int15_bios_call() */
97 static spinlock_t int15_lock;
98 
99 
100 /* This is a series of function that deals with
101  * setting & getting the hotplug resource table in some environment variable.
102  */
103 
104 /*
105  * We really shouldn't be doing this unless there is a _very_ good reason to!!!
106  * greg k-h
107  */
108 
109 
110 static u32 add_byte(u32 **p_buffer, u8 value, u32 *used, u32 *avail)
111 {
112 	u8 **tByte;
113 
114 	if ((*used + 1) > *avail)
115 		return(1);
116 
117 	*((u8 *)*p_buffer) = value;
118 	tByte = (u8 **)p_buffer;
119 	(*tByte)++;
120 	*used += 1;
121 	return(0);
122 }
123 
124 
125 static u32 add_dword(u32 **p_buffer, u32 value, u32 *used, u32 *avail)
126 {
127 	if ((*used + 4) > *avail)
128 		return(1);
129 
130 	**p_buffer = value;
131 	(*p_buffer)++;
132 	*used += 4;
133 	return(0);
134 }
135 
136 
137 /*
138  * check_for_compaq_ROM
139  *
140  * this routine verifies that the ROM OEM string is 'COMPAQ'
141  *
142  * returns 0 for non-Compaq ROM, 1 for Compaq ROM
143  */
144 static int check_for_compaq_ROM(void __iomem *rom_start)
145 {
146 	u8 temp1, temp2, temp3, temp4, temp5, temp6;
147 	int result = 0;
148 
149 	temp1 = readb(rom_start + 0xffea + 0);
150 	temp2 = readb(rom_start + 0xffea + 1);
151 	temp3 = readb(rom_start + 0xffea + 2);
152 	temp4 = readb(rom_start + 0xffea + 3);
153 	temp5 = readb(rom_start + 0xffea + 4);
154 	temp6 = readb(rom_start + 0xffea + 5);
155 	if ((temp1 == 'C') &&
156 	    (temp2 == 'O') &&
157 	    (temp3 == 'M') &&
158 	    (temp4 == 'P') &&
159 	    (temp5 == 'A') &&
160 	    (temp6 == 'Q')) {
161 		result = 1;
162 	}
163 	dbg("%s - returned %d\n", __func__, result);
164 	return result;
165 }
166 
167 
168 static u32 access_EV(u16 operation, u8 *ev_name, u8 *buffer, u32 *buf_size)
169 {
170 	unsigned long flags;
171 	int op = operation;
172 	int ret_val;
173 
174 	if (!compaq_int15_entry_point)
175 		return -ENODEV;
176 
177 	spin_lock_irqsave(&int15_lock, flags);
178 	__asm__ (
179 		"xorl   %%ebx,%%ebx\n" \
180 		"xorl    %%edx,%%edx\n" \
181 		"pushf\n" \
182 		"push %%cs\n" \
183 		"cli\n" \
184 		"call *%6\n"
185 		: "=c" (*buf_size), "=a" (ret_val)
186 		: "a" (op), "c" (*buf_size), "S" (ev_name),
187 		"D" (buffer), "m" (compaq_int15_entry_point)
188 		: "%ebx", "%edx");
189 	spin_unlock_irqrestore(&int15_lock, flags);
190 
191 	return((ret_val & 0xFF00) >> 8);
192 }
193 
194 
195 /*
196  * load_HRT
197  *
198  * Read the hot plug Resource Table from NVRAM
199  */
200 static int load_HRT(void __iomem *rom_start)
201 {
202 	u32 available;
203 	u32 temp_dword;
204 	u8 temp_byte = 0xFF;
205 	u32 rc;
206 
207 	if (!check_for_compaq_ROM(rom_start))
208 		return -ENODEV;
209 
210 	available = 1024;
211 
212 	/* Now load the EV */
213 	temp_dword = available;
214 
215 	rc = access_EV(READ_EV, "CQTHPS", evbuffer, &temp_dword);
216 
217 	evbuffer_length = temp_dword;
218 
219 	/* We're maintaining the resource lists so write FF to invalidate old
220 	 * info
221 	 */
222 	temp_dword = 1;
223 
224 	rc = access_EV(WRITE_EV, "CQTHPS", &temp_byte, &temp_dword);
225 
226 	return rc;
227 }
228 
229 
230 /*
231  * store_HRT
232  *
233  * Save the hot plug Resource Table in NVRAM
234  */
235 static u32 store_HRT(void __iomem *rom_start)
236 {
237 	u32 *buffer;
238 	u32 *pFill;
239 	u32 usedbytes;
240 	u32 available;
241 	u32 temp_dword;
242 	u32 rc;
243 	u8 loop;
244 	u8 numCtrl = 0;
245 	struct controller *ctrl;
246 	struct pci_resource *resNode;
247 	struct ev_hrt_header *p_EV_header;
248 	struct ev_hrt_ctrl *p_ev_ctrl;
249 
250 	available = 1024;
251 
252 	if (!check_for_compaq_ROM(rom_start))
253 		return(1);
254 
255 	buffer = (u32 *) evbuffer;
256 
257 	if (!buffer)
258 		return(1);
259 
260 	pFill = buffer;
261 	usedbytes = 0;
262 
263 	p_EV_header = (struct ev_hrt_header *) pFill;
264 
265 	ctrl = cpqhp_ctrl_list;
266 
267 	/* The revision of this structure */
268 	rc = add_byte(&pFill, 1 + ctrl->push_flag, &usedbytes, &available);
269 	if (rc)
270 		return(rc);
271 
272 	/* The number of controllers */
273 	rc = add_byte(&pFill, 1, &usedbytes, &available);
274 	if (rc)
275 		return(rc);
276 
277 	while (ctrl) {
278 		p_ev_ctrl = (struct ev_hrt_ctrl *) pFill;
279 
280 		numCtrl++;
281 
282 		/* The bus number */
283 		rc = add_byte(&pFill, ctrl->bus, &usedbytes, &available);
284 		if (rc)
285 			return(rc);
286 
287 		/* The device Number */
288 		rc = add_byte(&pFill, PCI_SLOT(ctrl->pci_dev->devfn), &usedbytes, &available);
289 		if (rc)
290 			return(rc);
291 
292 		/* The function Number */
293 		rc = add_byte(&pFill, PCI_FUNC(ctrl->pci_dev->devfn), &usedbytes, &available);
294 		if (rc)
295 			return(rc);
296 
297 		/* Skip the number of available entries */
298 		rc = add_dword(&pFill, 0, &usedbytes, &available);
299 		if (rc)
300 			return(rc);
301 
302 		/* Figure out memory Available */
303 
304 		resNode = ctrl->mem_head;
305 
306 		loop = 0;
307 
308 		while (resNode) {
309 			loop++;
310 
311 			/* base */
312 			rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
313 			if (rc)
314 				return(rc);
315 
316 			/* length */
317 			rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
318 			if (rc)
319 				return(rc);
320 
321 			resNode = resNode->next;
322 		}
323 
324 		/* Fill in the number of entries */
325 		p_ev_ctrl->mem_avail = loop;
326 
327 		/* Figure out prefetchable memory Available */
328 
329 		resNode = ctrl->p_mem_head;
330 
331 		loop = 0;
332 
333 		while (resNode) {
334 			loop++;
335 
336 			/* base */
337 			rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
338 			if (rc)
339 				return(rc);
340 
341 			/* length */
342 			rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
343 			if (rc)
344 				return(rc);
345 
346 			resNode = resNode->next;
347 		}
348 
349 		/* Fill in the number of entries */
350 		p_ev_ctrl->p_mem_avail = loop;
351 
352 		/* Figure out IO Available */
353 
354 		resNode = ctrl->io_head;
355 
356 		loop = 0;
357 
358 		while (resNode) {
359 			loop++;
360 
361 			/* base */
362 			rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
363 			if (rc)
364 				return(rc);
365 
366 			/* length */
367 			rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
368 			if (rc)
369 				return(rc);
370 
371 			resNode = resNode->next;
372 		}
373 
374 		/* Fill in the number of entries */
375 		p_ev_ctrl->io_avail = loop;
376 
377 		/* Figure out bus Available */
378 
379 		resNode = ctrl->bus_head;
380 
381 		loop = 0;
382 
383 		while (resNode) {
384 			loop++;
385 
386 			/* base */
387 			rc = add_dword(&pFill, resNode->base, &usedbytes, &available);
388 			if (rc)
389 				return(rc);
390 
391 			/* length */
392 			rc = add_dword(&pFill, resNode->length, &usedbytes, &available);
393 			if (rc)
394 				return(rc);
395 
396 			resNode = resNode->next;
397 		}
398 
399 		/* Fill in the number of entries */
400 		p_ev_ctrl->bus_avail = loop;
401 
402 		ctrl = ctrl->next;
403 	}
404 
405 	p_EV_header->num_of_ctrl = numCtrl;
406 
407 	/* Now store the EV */
408 
409 	temp_dword = usedbytes;
410 
411 	rc = access_EV(WRITE_EV, "CQTHPS", (u8 *) buffer, &temp_dword);
412 
413 	dbg("usedbytes = 0x%x, length = 0x%x\n", usedbytes, temp_dword);
414 
415 	evbuffer_length = temp_dword;
416 
417 	if (rc) {
418 		err(msg_unable_to_save);
419 		return(1);
420 	}
421 
422 	return(0);
423 }
424 
425 
426 void compaq_nvram_init(void __iomem *rom_start)
427 {
428 	if (rom_start)
429 		compaq_int15_entry_point = (rom_start + ROM_INT15_PHY_ADDR - ROM_PHY_ADDR);
430 
431 	dbg("int15 entry  = %p\n", compaq_int15_entry_point);
432 
433 	/* initialize our int15 lock */
434 	spin_lock_init(&int15_lock);
435 }
436 
437 
438 int compaq_nvram_load(void __iomem *rom_start, struct controller *ctrl)
439 {
440 	u8 bus, device, function;
441 	u8 nummem, numpmem, numio, numbus;
442 	u32 rc;
443 	u8 *p_byte;
444 	struct pci_resource *mem_node;
445 	struct pci_resource *p_mem_node;
446 	struct pci_resource *io_node;
447 	struct pci_resource *bus_node;
448 	struct ev_hrt_ctrl *p_ev_ctrl;
449 	struct ev_hrt_header *p_EV_header;
450 
451 	if (!evbuffer_init) {
452 		/* Read the resource list information in from NVRAM */
453 		if (load_HRT(rom_start))
454 			memset(evbuffer, 0, 1024);
455 
456 		evbuffer_init = 1;
457 	}
458 
459 	/* If we saved information in NVRAM, use it now */
460 	p_EV_header = (struct ev_hrt_header *) evbuffer;
461 
462 	/* The following code is for systems where version 1.0 of this
463 	 * driver has been loaded, but doesn't support the hardware.
464 	 * In that case, the driver would incorrectly store something
465 	 * in NVRAM.
466 	 */
467 	if ((p_EV_header->Version == 2) ||
468 	    ((p_EV_header->Version == 1) && !ctrl->push_flag)) {
469 		p_byte = &(p_EV_header->next);
470 
471 		p_ev_ctrl = (struct ev_hrt_ctrl *) &(p_EV_header->next);
472 
473 		p_byte += 3;
474 
475 		if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
476 			return 2;
477 
478 		bus = p_ev_ctrl->bus;
479 		device = p_ev_ctrl->device;
480 		function = p_ev_ctrl->function;
481 
482 		while ((bus != ctrl->bus) ||
483 		       (device != PCI_SLOT(ctrl->pci_dev->devfn)) ||
484 		       (function != PCI_FUNC(ctrl->pci_dev->devfn))) {
485 			nummem = p_ev_ctrl->mem_avail;
486 			numpmem = p_ev_ctrl->p_mem_avail;
487 			numio = p_ev_ctrl->io_avail;
488 			numbus = p_ev_ctrl->bus_avail;
489 
490 			p_byte += 4;
491 
492 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
493 				return 2;
494 
495 			/* Skip forward to the next entry */
496 			p_byte += (nummem + numpmem + numio + numbus) * 8;
497 
498 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
499 				return 2;
500 
501 			p_ev_ctrl = (struct ev_hrt_ctrl *) p_byte;
502 
503 			p_byte += 3;
504 
505 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
506 				return 2;
507 
508 			bus = p_ev_ctrl->bus;
509 			device = p_ev_ctrl->device;
510 			function = p_ev_ctrl->function;
511 		}
512 
513 		nummem = p_ev_ctrl->mem_avail;
514 		numpmem = p_ev_ctrl->p_mem_avail;
515 		numio = p_ev_ctrl->io_avail;
516 		numbus = p_ev_ctrl->bus_avail;
517 
518 		p_byte += 4;
519 
520 		if (p_byte > ((u8 *)p_EV_header + evbuffer_length))
521 			return 2;
522 
523 		while (nummem--) {
524 			mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
525 
526 			if (!mem_node)
527 				break;
528 
529 			mem_node->base = *(u32 *)p_byte;
530 			dbg("mem base = %8.8x\n", mem_node->base);
531 			p_byte += 4;
532 
533 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
534 				kfree(mem_node);
535 				return 2;
536 			}
537 
538 			mem_node->length = *(u32 *)p_byte;
539 			dbg("mem length = %8.8x\n", mem_node->length);
540 			p_byte += 4;
541 
542 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
543 				kfree(mem_node);
544 				return 2;
545 			}
546 
547 			mem_node->next = ctrl->mem_head;
548 			ctrl->mem_head = mem_node;
549 		}
550 
551 		while (numpmem--) {
552 			p_mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
553 
554 			if (!p_mem_node)
555 				break;
556 
557 			p_mem_node->base = *(u32 *)p_byte;
558 			dbg("pre-mem base = %8.8x\n", p_mem_node->base);
559 			p_byte += 4;
560 
561 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
562 				kfree(p_mem_node);
563 				return 2;
564 			}
565 
566 			p_mem_node->length = *(u32 *)p_byte;
567 			dbg("pre-mem length = %8.8x\n", p_mem_node->length);
568 			p_byte += 4;
569 
570 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
571 				kfree(p_mem_node);
572 				return 2;
573 			}
574 
575 			p_mem_node->next = ctrl->p_mem_head;
576 			ctrl->p_mem_head = p_mem_node;
577 		}
578 
579 		while (numio--) {
580 			io_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
581 
582 			if (!io_node)
583 				break;
584 
585 			io_node->base = *(u32 *)p_byte;
586 			dbg("io base = %8.8x\n", io_node->base);
587 			p_byte += 4;
588 
589 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
590 				kfree(io_node);
591 				return 2;
592 			}
593 
594 			io_node->length = *(u32 *)p_byte;
595 			dbg("io length = %8.8x\n", io_node->length);
596 			p_byte += 4;
597 
598 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
599 				kfree(io_node);
600 				return 2;
601 			}
602 
603 			io_node->next = ctrl->io_head;
604 			ctrl->io_head = io_node;
605 		}
606 
607 		while (numbus--) {
608 			bus_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
609 
610 			if (!bus_node)
611 				break;
612 
613 			bus_node->base = *(u32 *)p_byte;
614 			p_byte += 4;
615 
616 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
617 				kfree(bus_node);
618 				return 2;
619 			}
620 
621 			bus_node->length = *(u32 *)p_byte;
622 			p_byte += 4;
623 
624 			if (p_byte > ((u8 *)p_EV_header + evbuffer_length)) {
625 				kfree(bus_node);
626 				return 2;
627 			}
628 
629 			bus_node->next = ctrl->bus_head;
630 			ctrl->bus_head = bus_node;
631 		}
632 
633 		/* If all of the following fail, we don't have any resources for
634 		 * hot plug add
635 		 */
636 		rc = 1;
637 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->mem_head));
638 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->p_mem_head));
639 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->io_head));
640 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->bus_head));
641 
642 		if (rc)
643 			return(rc);
644 	} else {
645 		if ((evbuffer[0] != 0) && (!ctrl->push_flag))
646 			return 1;
647 	}
648 
649 	return 0;
650 }
651 
652 
653 int compaq_nvram_store(void __iomem *rom_start)
654 {
655 	int rc = 1;
656 
657 	if (rom_start == NULL)
658 		return -ENODEV;
659 
660 	if (evbuffer_init) {
661 		rc = store_HRT(rom_start);
662 		if (rc)
663 			err(msg_unable_to_save);
664 	}
665 	return rc;
666 }
667 
668