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/init.h>
38 #include <asm/uaccess.h>
39 #include "cpqphp.h"
40 #include "cpqphp_nvram.h"
41 
42 
43 #define ROM_INT15_PHY_ADDR		0x0FF859
44 #define READ_EV				0xD8A4
45 #define WRITE_EV			0xD8A5
46 
47 struct register_foo {
48 	union {
49 		unsigned long lword;		/* eax */
50 		unsigned short word;		/* ax */
51 
52 		struct {
53 			unsigned char low;	/* al */
54 			unsigned char high;	/* ah */
55 		} byte;
56 	} data;
57 
58 	unsigned char opcode;	/* see below */
59 	unsigned long length;	/* if the reg. is a pointer, how much data */
60 } __attribute__ ((packed));
61 
62 struct all_reg {
63 	struct register_foo eax_reg;
64 	struct register_foo ebx_reg;
65 	struct register_foo ecx_reg;
66 	struct register_foo edx_reg;
67 	struct register_foo edi_reg;
68 	struct register_foo esi_reg;
69 	struct register_foo eflags_reg;
70 } __attribute__ ((packed));
71 
72 
73 struct ev_hrt_header {
74 	u8 Version;
75 	u8 num_of_ctrl;
76 	u8 next;
77 };
78 
79 struct ev_hrt_ctrl {
80 	u8 bus;
81 	u8 device;
82 	u8 function;
83 	u8 mem_avail;
84 	u8 p_mem_avail;
85 	u8 io_avail;
86 	u8 bus_avail;
87 	u8 next;
88 };
89 
90 
91 static u8 evbuffer_init;
92 static u8 evbuffer_length;
93 static u8 evbuffer[1024];
94 
95 static void __iomem *compaq_int15_entry_point;
96 
97 /* lock for ordering int15_bios_call() */
98 static spinlock_t int15_lock;
99 
100 
101 /* This is a series of function that deals with
102  * setting & getting the hotplug resource table in some environment variable.
103  */
104 
105 /*
106  * We really shouldn't be doing this unless there is a _very_ good reason to!!!
107  * greg k-h
108  */
109 
110 
111 static u32 add_byte( u32 **p_buffer, u8 value, u32 *used, u32 *avail)
112 {
113 	u8 **tByte;
114 
115 	if ((*used + 1) > *avail)
116 		return(1);
117 
118 	*((u8*)*p_buffer) = value;
119 	tByte = (u8**)p_buffer;
120 	(*tByte)++;
121 	*used+=1;
122 	return(0);
123 }
124 
125 
126 static u32 add_dword( u32 **p_buffer, u32 value, u32 *used, u32 *avail)
127 {
128 	if ((*used + 4) > *avail)
129 		return(1);
130 
131 	**p_buffer = value;
132 	(*p_buffer)++;
133 	*used+=4;
134 	return(0);
135 }
136 
137 
138 /*
139  * check_for_compaq_ROM
140  *
141  * this routine verifies that the ROM OEM string is 'COMPAQ'
142  *
143  * returns 0 for non-Compaq ROM, 1 for Compaq ROM
144  */
145 static int check_for_compaq_ROM (void __iomem *rom_start)
146 {
147 	u8 temp1, temp2, temp3, temp4, temp5, temp6;
148 	int result = 0;
149 
150 	temp1 = readb(rom_start + 0xffea + 0);
151 	temp2 = readb(rom_start + 0xffea + 1);
152 	temp3 = readb(rom_start + 0xffea + 2);
153 	temp4 = readb(rom_start + 0xffea + 3);
154 	temp5 = readb(rom_start + 0xffea + 4);
155 	temp6 = readb(rom_start + 0xffea + 5);
156 	if ((temp1 == 'C') &&
157 	    (temp2 == 'O') &&
158 	    (temp3 == 'M') &&
159 	    (temp4 == 'P') &&
160 	    (temp5 == 'A') &&
161 	    (temp6 == 'Q')) {
162 		result = 1;
163 	}
164 	dbg ("%s - returned %d\n", __func__, result);
165 	return result;
166 }
167 
168 
169 static u32 access_EV (u16 operation, u8 *ev_name, u8 *buffer, u32 *buf_size)
170 {
171 	unsigned long flags;
172 	int op = operation;
173 	int ret_val;
174 
175 	if (!compaq_int15_entry_point)
176 		return -ENODEV;
177 
178 	spin_lock_irqsave(&int15_lock, flags);
179 	__asm__ (
180 		"xorl   %%ebx,%%ebx\n" \
181 		"xorl    %%edx,%%edx\n" \
182 		"pushf\n" \
183 		"push %%cs\n" \
184 		"cli\n" \
185 		"call *%6\n"
186 		: "=c" (*buf_size), "=a" (ret_val)
187 		: "a" (op), "c" (*buf_size), "S" (ev_name),
188 		"D" (buffer), "m" (compaq_int15_entry_point)
189 		: "%ebx", "%edx");
190 	spin_unlock_irqrestore(&int15_lock, flags);
191 
192 	return((ret_val & 0xFF00) >> 8);
193 }
194 
195 
196 /*
197  * load_HRT
198  *
199  * Read the hot plug Resource Table from NVRAM
200  */
201 static int load_HRT (void __iomem *rom_start)
202 {
203 	u32 available;
204 	u32 temp_dword;
205 	u8 temp_byte = 0xFF;
206 	u32 rc;
207 
208 	if (!check_for_compaq_ROM(rom_start)) {
209 		return -ENODEV;
210 	}
211 
212 	available = 1024;
213 
214 	/* Now load the EV */
215 	temp_dword = available;
216 
217 	rc = access_EV(READ_EV, "CQTHPS", evbuffer, &temp_dword);
218 
219 	evbuffer_length = temp_dword;
220 
221 	/* We're maintaining the resource lists so write FF to invalidate old
222 	 * info
223 	 */
224 	temp_dword = 1;
225 
226 	rc = access_EV(WRITE_EV, "CQTHPS", &temp_byte, &temp_dword);
227 
228 	return rc;
229 }
230 
231 
232 /*
233  * store_HRT
234  *
235  * Save the hot plug Resource Table in NVRAM
236  */
237 static u32 store_HRT (void __iomem *rom_start)
238 {
239 	u32 *buffer;
240 	u32 *pFill;
241 	u32 usedbytes;
242 	u32 available;
243 	u32 temp_dword;
244 	u32 rc;
245 	u8 loop;
246 	u8 numCtrl = 0;
247 	struct controller *ctrl;
248 	struct pci_resource *resNode;
249 	struct ev_hrt_header *p_EV_header;
250 	struct ev_hrt_ctrl *p_ev_ctrl;
251 
252 	available = 1024;
253 
254 	if (!check_for_compaq_ROM(rom_start)) {
255 		return(1);
256 	}
257 
258 	buffer = (u32*) evbuffer;
259 
260 	if (!buffer)
261 		return(1);
262 
263 	pFill = buffer;
264 	usedbytes = 0;
265 
266 	p_EV_header = (struct ev_hrt_header *) pFill;
267 
268 	ctrl = cpqhp_ctrl_list;
269 
270 	/* The revision of this structure */
271 	rc = add_byte( &pFill, 1 + ctrl->push_flag, &usedbytes, &available);
272 	if (rc)
273 		return(rc);
274 
275 	/* The number of controllers */
276 	rc = add_byte( &pFill, 1, &usedbytes, &available);
277 	if (rc)
278 		return(rc);
279 
280 	while (ctrl) {
281 		p_ev_ctrl = (struct ev_hrt_ctrl *) pFill;
282 
283 		numCtrl++;
284 
285 		/* The bus number */
286 		rc = add_byte( &pFill, ctrl->bus, &usedbytes, &available);
287 		if (rc)
288 			return(rc);
289 
290 		/* The device Number */
291 		rc = add_byte( &pFill, PCI_SLOT(ctrl->pci_dev->devfn), &usedbytes, &available);
292 		if (rc)
293 			return(rc);
294 
295 		/* The function Number */
296 		rc = add_byte( &pFill, PCI_FUNC(ctrl->pci_dev->devfn), &usedbytes, &available);
297 		if (rc)
298 			return(rc);
299 
300 		/* Skip the number of available entries */
301 		rc = add_dword( &pFill, 0, &usedbytes, &available);
302 		if (rc)
303 			return(rc);
304 
305 		/* Figure out memory Available */
306 
307 		resNode = ctrl->mem_head;
308 
309 		loop = 0;
310 
311 		while (resNode) {
312 			loop ++;
313 
314 			/* base */
315 			rc = add_dword( &pFill, resNode->base, &usedbytes, &available);
316 			if (rc)
317 				return(rc);
318 
319 			/* length */
320 			rc = add_dword( &pFill, resNode->length, &usedbytes, &available);
321 			if (rc)
322 				return(rc);
323 
324 			resNode = resNode->next;
325 		}
326 
327 		/* Fill in the number of entries */
328 		p_ev_ctrl->mem_avail = loop;
329 
330 		/* Figure out prefetchable memory Available */
331 
332 		resNode = ctrl->p_mem_head;
333 
334 		loop = 0;
335 
336 		while (resNode) {
337 			loop ++;
338 
339 			/* base */
340 			rc = add_dword( &pFill, resNode->base, &usedbytes, &available);
341 			if (rc)
342 				return(rc);
343 
344 			/* length */
345 			rc = add_dword( &pFill, resNode->length, &usedbytes, &available);
346 			if (rc)
347 				return(rc);
348 
349 			resNode = resNode->next;
350 		}
351 
352 		/* Fill in the number of entries */
353 		p_ev_ctrl->p_mem_avail = loop;
354 
355 		/* Figure out IO Available */
356 
357 		resNode = ctrl->io_head;
358 
359 		loop = 0;
360 
361 		while (resNode) {
362 			loop ++;
363 
364 			/* base */
365 			rc = add_dword( &pFill, resNode->base, &usedbytes, &available);
366 			if (rc)
367 				return(rc);
368 
369 			/* length */
370 			rc = add_dword( &pFill, resNode->length, &usedbytes, &available);
371 			if (rc)
372 				return(rc);
373 
374 			resNode = resNode->next;
375 		}
376 
377 		/* Fill in the number of entries */
378 		p_ev_ctrl->io_avail = loop;
379 
380 		/* Figure out bus Available */
381 
382 		resNode = ctrl->bus_head;
383 
384 		loop = 0;
385 
386 		while (resNode) {
387 			loop ++;
388 
389 			/* base */
390 			rc = add_dword( &pFill, resNode->base, &usedbytes, &available);
391 			if (rc)
392 				return(rc);
393 
394 			/* length */
395 			rc = add_dword( &pFill, resNode->length, &usedbytes, &available);
396 			if (rc)
397 				return(rc);
398 
399 			resNode = resNode->next;
400 		}
401 
402 		/* Fill in the number of entries */
403 		p_ev_ctrl->bus_avail = loop;
404 
405 		ctrl = ctrl->next;
406 	}
407 
408 	p_EV_header->num_of_ctrl = numCtrl;
409 
410 	/* Now store the EV */
411 
412 	temp_dword = usedbytes;
413 
414 	rc = access_EV(WRITE_EV, "CQTHPS", (u8*) buffer, &temp_dword);
415 
416 	dbg("usedbytes = 0x%x, length = 0x%x\n", usedbytes, temp_dword);
417 
418 	evbuffer_length = temp_dword;
419 
420 	if (rc) {
421 		err(msg_unable_to_save);
422 		return(1);
423 	}
424 
425 	return(0);
426 }
427 
428 
429 void compaq_nvram_init (void __iomem *rom_start)
430 {
431 	if (rom_start) {
432 		compaq_int15_entry_point = (rom_start + ROM_INT15_PHY_ADDR - ROM_PHY_ADDR);
433 	}
434 	dbg("int15 entry  = %p\n", compaq_int15_entry_point);
435 
436 	/* initialize our int15 lock */
437 	spin_lock_init(&int15_lock);
438 }
439 
440 
441 int compaq_nvram_load (void __iomem *rom_start, struct controller *ctrl)
442 {
443 	u8 bus, device, function;
444 	u8 nummem, numpmem, numio, numbus;
445 	u32 rc;
446 	u8 *p_byte;
447 	struct pci_resource *mem_node;
448 	struct pci_resource *p_mem_node;
449 	struct pci_resource *io_node;
450 	struct pci_resource *bus_node;
451 	struct ev_hrt_ctrl *p_ev_ctrl;
452 	struct ev_hrt_header *p_EV_header;
453 
454 	if (!evbuffer_init) {
455 		/* Read the resource list information in from NVRAM */
456 		if (load_HRT(rom_start))
457 			memset (evbuffer, 0, 1024);
458 
459 		evbuffer_init = 1;
460 	}
461 
462 	/* If we saved information in NVRAM, use it now */
463 	p_EV_header = (struct ev_hrt_header *) evbuffer;
464 
465 	/* The following code is for systems where version 1.0 of this
466 	 * driver has been loaded, but doesn't support the hardware.
467 	 * In that case, the driver would incorrectly store something
468 	 * in NVRAM.
469 	 */
470 	if ((p_EV_header->Version == 2) ||
471 	    ((p_EV_header->Version == 1) && !ctrl->push_flag)) {
472 		p_byte = &(p_EV_header->next);
473 
474 		p_ev_ctrl = (struct ev_hrt_ctrl *) &(p_EV_header->next);
475 
476 		p_byte += 3;
477 
478 		if (p_byte > ((u8*)p_EV_header + evbuffer_length))
479 			return 2;
480 
481 		bus = p_ev_ctrl->bus;
482 		device = p_ev_ctrl->device;
483 		function = p_ev_ctrl->function;
484 
485 		while ((bus != ctrl->bus) ||
486 		       (device != PCI_SLOT(ctrl->pci_dev->devfn)) ||
487 		       (function != PCI_FUNC(ctrl->pci_dev->devfn))) {
488 			nummem = p_ev_ctrl->mem_avail;
489 			numpmem = p_ev_ctrl->p_mem_avail;
490 			numio = p_ev_ctrl->io_avail;
491 			numbus = p_ev_ctrl->bus_avail;
492 
493 			p_byte += 4;
494 
495 			if (p_byte > ((u8*)p_EV_header + evbuffer_length))
496 				return 2;
497 
498 			/* Skip forward to the next entry */
499 			p_byte += (nummem + numpmem + numio + numbus) * 8;
500 
501 			if (p_byte > ((u8*)p_EV_header + evbuffer_length))
502 				return 2;
503 
504 			p_ev_ctrl = (struct ev_hrt_ctrl *) p_byte;
505 
506 			p_byte += 3;
507 
508 			if (p_byte > ((u8*)p_EV_header + evbuffer_length))
509 				return 2;
510 
511 			bus = p_ev_ctrl->bus;
512 			device = p_ev_ctrl->device;
513 			function = p_ev_ctrl->function;
514 		}
515 
516 		nummem = p_ev_ctrl->mem_avail;
517 		numpmem = p_ev_ctrl->p_mem_avail;
518 		numio = p_ev_ctrl->io_avail;
519 		numbus = p_ev_ctrl->bus_avail;
520 
521 		p_byte += 4;
522 
523 		if (p_byte > ((u8*)p_EV_header + evbuffer_length))
524 			return 2;
525 
526 		while (nummem--) {
527 			mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
528 
529 			if (!mem_node)
530 				break;
531 
532 			mem_node->base = *(u32*)p_byte;
533 			dbg("mem base = %8.8x\n",mem_node->base);
534 			p_byte += 4;
535 
536 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
537 				kfree(mem_node);
538 				return 2;
539 			}
540 
541 			mem_node->length = *(u32*)p_byte;
542 			dbg("mem length = %8.8x\n",mem_node->length);
543 			p_byte += 4;
544 
545 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
546 				kfree(mem_node);
547 				return 2;
548 			}
549 
550 			mem_node->next = ctrl->mem_head;
551 			ctrl->mem_head = mem_node;
552 		}
553 
554 		while (numpmem--) {
555 			p_mem_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
556 
557 			if (!p_mem_node)
558 				break;
559 
560 			p_mem_node->base = *(u32*)p_byte;
561 			dbg("pre-mem base = %8.8x\n",p_mem_node->base);
562 			p_byte += 4;
563 
564 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
565 				kfree(p_mem_node);
566 				return 2;
567 			}
568 
569 			p_mem_node->length = *(u32*)p_byte;
570 			dbg("pre-mem length = %8.8x\n",p_mem_node->length);
571 			p_byte += 4;
572 
573 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
574 				kfree(p_mem_node);
575 				return 2;
576 			}
577 
578 			p_mem_node->next = ctrl->p_mem_head;
579 			ctrl->p_mem_head = p_mem_node;
580 		}
581 
582 		while (numio--) {
583 			io_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
584 
585 			if (!io_node)
586 				break;
587 
588 			io_node->base = *(u32*)p_byte;
589 			dbg("io base = %8.8x\n",io_node->base);
590 			p_byte += 4;
591 
592 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
593 				kfree(io_node);
594 				return 2;
595 			}
596 
597 			io_node->length = *(u32*)p_byte;
598 			dbg("io length = %8.8x\n",io_node->length);
599 			p_byte += 4;
600 
601 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
602 				kfree(io_node);
603 				return 2;
604 			}
605 
606 			io_node->next = ctrl->io_head;
607 			ctrl->io_head = io_node;
608 		}
609 
610 		while (numbus--) {
611 			bus_node = kmalloc(sizeof(struct pci_resource), GFP_KERNEL);
612 
613 			if (!bus_node)
614 				break;
615 
616 			bus_node->base = *(u32*)p_byte;
617 			p_byte += 4;
618 
619 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
620 				kfree(bus_node);
621 				return 2;
622 			}
623 
624 			bus_node->length = *(u32*)p_byte;
625 			p_byte += 4;
626 
627 			if (p_byte > ((u8*)p_EV_header + evbuffer_length)) {
628 				kfree(bus_node);
629 				return 2;
630 			}
631 
632 			bus_node->next = ctrl->bus_head;
633 			ctrl->bus_head = bus_node;
634 		}
635 
636 		/* If all of the following fail, we don't have any resources for
637 		 * hot plug add
638 		 */
639 		rc = 1;
640 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->mem_head));
641 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->p_mem_head));
642 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->io_head));
643 		rc &= cpqhp_resource_sort_and_combine(&(ctrl->bus_head));
644 
645 		if (rc)
646 			return(rc);
647 	} else {
648 		if ((evbuffer[0] != 0) && (!ctrl->push_flag))
649 			return 1;
650 	}
651 
652 	return 0;
653 }
654 
655 
656 int compaq_nvram_store (void __iomem *rom_start)
657 {
658 	int rc = 1;
659 
660 	if (rom_start == NULL)
661 		return -ENODEV;
662 
663 	if (evbuffer_init) {
664 		rc = store_HRT(rom_start);
665 		if (rc) {
666 			err(msg_unable_to_save);
667 		}
668 	}
669 	return rc;
670 }
671 
672