xref: /openbmc/linux/drivers/pci/hotplug/ibmphp_hpc.c (revision 87c2ce3b)
1 /*
2  * IBM Hot Plug Controller Driver
3  *
4  * Written By: Jyoti Shah, IBM Corporation
5  *
6  * Copyright (C) 2001-2003 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 <gregkh@us.ibm.com>
26  *                  <jshah@us.ibm.com>
27  *
28  */
29 
30 #include <linux/wait.h>
31 #include <linux/time.h>
32 #include <linux/delay.h>
33 #include <linux/module.h>
34 #include <linux/pci.h>
35 #include <linux/smp_lock.h>
36 #include <linux/init.h>
37 #include "ibmphp.h"
38 
39 static int to_debug = FALSE;
40 #define debug_polling(fmt, arg...)	do { if (to_debug) debug (fmt, arg); } while (0)
41 
42 //----------------------------------------------------------------------------
43 // timeout values
44 //----------------------------------------------------------------------------
45 #define CMD_COMPLETE_TOUT_SEC	60	// give HPC 60 sec to finish cmd
46 #define HPC_CTLR_WORKING_TOUT	60	// give HPC 60 sec to finish cmd
47 #define HPC_GETACCESS_TIMEOUT	60	// seconds
48 #define POLL_INTERVAL_SEC	2	// poll HPC every 2 seconds
49 #define POLL_LATCH_CNT		5	// poll latch 5 times, then poll slots
50 
51 //----------------------------------------------------------------------------
52 // Winnipeg Architected Register Offsets
53 //----------------------------------------------------------------------------
54 #define WPG_I2CMBUFL_OFFSET	0x08	// I2C Message Buffer Low
55 #define WPG_I2CMOSUP_OFFSET	0x10	// I2C Master Operation Setup Reg
56 #define WPG_I2CMCNTL_OFFSET	0x20	// I2C Master Control Register
57 #define WPG_I2CPARM_OFFSET	0x40	// I2C Parameter Register
58 #define WPG_I2CSTAT_OFFSET	0x70	// I2C Status Register
59 
60 //----------------------------------------------------------------------------
61 // Winnipeg Store Type commands (Add this commands to the register offset)
62 //----------------------------------------------------------------------------
63 #define WPG_I2C_AND		0x1000	// I2C AND operation
64 #define WPG_I2C_OR		0x2000	// I2C OR operation
65 
66 //----------------------------------------------------------------------------
67 // Command set for I2C Master Operation Setup Register
68 //----------------------------------------------------------------------------
69 #define WPG_READATADDR_MASK	0x00010000	// read,bytes,I2C shifted,index
70 #define WPG_WRITEATADDR_MASK	0x40010000	// write,bytes,I2C shifted,index
71 #define WPG_READDIRECT_MASK	0x10010000
72 #define WPG_WRITEDIRECT_MASK	0x60010000
73 
74 
75 //----------------------------------------------------------------------------
76 // bit masks for I2C Master Control Register
77 //----------------------------------------------------------------------------
78 #define WPG_I2CMCNTL_STARTOP_MASK	0x00000002	// Start the Operation
79 
80 //----------------------------------------------------------------------------
81 //
82 //----------------------------------------------------------------------------
83 #define WPG_I2C_IOREMAP_SIZE	0x2044	// size of linear address interval
84 
85 //----------------------------------------------------------------------------
86 // command index
87 //----------------------------------------------------------------------------
88 #define WPG_1ST_SLOT_INDEX	0x01	// index - 1st slot for ctlr
89 #define WPG_CTLR_INDEX		0x0F	// index - ctlr
90 #define WPG_1ST_EXTSLOT_INDEX	0x10	// index - 1st ext slot for ctlr
91 #define WPG_1ST_BUS_INDEX	0x1F	// index - 1st bus for ctlr
92 
93 //----------------------------------------------------------------------------
94 // macro utilities
95 //----------------------------------------------------------------------------
96 // if bits 20,22,25,26,27,29,30 are OFF return TRUE
97 #define HPC_I2CSTATUS_CHECK(s)	((u8)((s & 0x00000A76) ? FALSE : TRUE))
98 
99 //----------------------------------------------------------------------------
100 // global variables
101 //----------------------------------------------------------------------------
102 static int ibmphp_shutdown;
103 static int tid_poll;
104 static struct semaphore sem_hpcaccess;	// lock access to HPC
105 static struct semaphore semOperations;	// lock all operations and
106 					// access to data structures
107 static struct semaphore sem_exit;	// make sure polling thread goes away
108 //----------------------------------------------------------------------------
109 // local function prototypes
110 //----------------------------------------------------------------------------
111 static u8 i2c_ctrl_read (struct controller *, void __iomem *, u8);
112 static u8 i2c_ctrl_write (struct controller *, void __iomem *, u8, u8);
113 static u8 hpc_writecmdtoindex (u8, u8);
114 static u8 hpc_readcmdtoindex (u8, u8);
115 static void get_hpc_access (void);
116 static void free_hpc_access (void);
117 static void poll_hpc (void);
118 static int process_changeinstatus (struct slot *, struct slot *);
119 static int process_changeinlatch (u8, u8, struct controller *);
120 static int hpc_poll_thread (void *);
121 static int hpc_wait_ctlr_notworking (int, struct controller *, void __iomem *, u8 *);
122 //----------------------------------------------------------------------------
123 
124 
125 /*----------------------------------------------------------------------
126 * Name:    ibmphp_hpc_initvars
127 *
128 * Action:  initialize semaphores and variables
129 *---------------------------------------------------------------------*/
130 void __init ibmphp_hpc_initvars (void)
131 {
132 	debug ("%s - Entry\n", __FUNCTION__);
133 
134 	init_MUTEX (&sem_hpcaccess);
135 	init_MUTEX (&semOperations);
136 	init_MUTEX_LOCKED (&sem_exit);
137 	to_debug = FALSE;
138 	ibmphp_shutdown = FALSE;
139 	tid_poll = 0;
140 
141 	debug ("%s - Exit\n", __FUNCTION__);
142 }
143 
144 /*----------------------------------------------------------------------
145 * Name:    i2c_ctrl_read
146 *
147 * Action:  read from HPC over I2C
148 *
149 *---------------------------------------------------------------------*/
150 static u8 i2c_ctrl_read (struct controller *ctlr_ptr, void __iomem *WPGBbar, u8 index)
151 {
152 	u8 status;
153 	int i;
154 	void __iomem *wpg_addr;	// base addr + offset
155 	unsigned long wpg_data;	// data to/from WPG LOHI format
156 	unsigned long ultemp;
157 	unsigned long data;	// actual data HILO format
158 
159 	debug_polling ("%s - Entry WPGBbar[%p] index[%x] \n", __FUNCTION__, WPGBbar, index);
160 
161 	//--------------------------------------------------------------------
162 	// READ - step 1
163 	// read at address, byte length, I2C address (shifted), index
164 	// or read direct, byte length, index
165 	if (ctlr_ptr->ctlr_type == 0x02) {
166 		data = WPG_READATADDR_MASK;
167 		// fill in I2C address
168 		ultemp = (unsigned long)ctlr_ptr->u.wpeg_ctlr.i2c_addr;
169 		ultemp = ultemp >> 1;
170 		data |= (ultemp << 8);
171 
172 		// fill in index
173 		data |= (unsigned long)index;
174 	} else if (ctlr_ptr->ctlr_type == 0x04) {
175 		data = WPG_READDIRECT_MASK;
176 
177 		// fill in index
178 		ultemp = (unsigned long)index;
179 		ultemp = ultemp << 8;
180 		data |= ultemp;
181 	} else {
182 		err ("this controller type is not supported \n");
183 		return HPC_ERROR;
184 	}
185 
186 	wpg_data = swab32 (data);	// swap data before writing
187 	wpg_addr = WPGBbar + WPG_I2CMOSUP_OFFSET;
188 	writel (wpg_data, wpg_addr);
189 
190 	//--------------------------------------------------------------------
191 	// READ - step 2 : clear the message buffer
192 	data = 0x00000000;
193 	wpg_data = swab32 (data);
194 	wpg_addr = WPGBbar + WPG_I2CMBUFL_OFFSET;
195 	writel (wpg_data, wpg_addr);
196 
197 	//--------------------------------------------------------------------
198 	// READ - step 3 : issue start operation, I2C master control bit 30:ON
199 	//                 2020 : [20] OR operation at [20] offset 0x20
200 	data = WPG_I2CMCNTL_STARTOP_MASK;
201 	wpg_data = swab32 (data);
202 	wpg_addr = WPGBbar + WPG_I2CMCNTL_OFFSET + WPG_I2C_OR;
203 	writel (wpg_data, wpg_addr);
204 
205 	//--------------------------------------------------------------------
206 	// READ - step 4 : wait until start operation bit clears
207 	i = CMD_COMPLETE_TOUT_SEC;
208 	while (i) {
209 		msleep(10);
210 		wpg_addr = WPGBbar + WPG_I2CMCNTL_OFFSET;
211 		wpg_data = readl (wpg_addr);
212 		data = swab32 (wpg_data);
213 		if (!(data & WPG_I2CMCNTL_STARTOP_MASK))
214 			break;
215 		i--;
216 	}
217 	if (i == 0) {
218 		debug ("%s - Error : WPG timeout\n", __FUNCTION__);
219 		return HPC_ERROR;
220 	}
221 	//--------------------------------------------------------------------
222 	// READ - step 5 : read I2C status register
223 	i = CMD_COMPLETE_TOUT_SEC;
224 	while (i) {
225 		msleep(10);
226 		wpg_addr = WPGBbar + WPG_I2CSTAT_OFFSET;
227 		wpg_data = readl (wpg_addr);
228 		data = swab32 (wpg_data);
229 		if (HPC_I2CSTATUS_CHECK (data))
230 			break;
231 		i--;
232 	}
233 	if (i == 0) {
234 		debug ("ctrl_read - Exit Error:I2C timeout\n");
235 		return HPC_ERROR;
236 	}
237 
238 	//--------------------------------------------------------------------
239 	// READ - step 6 : get DATA
240 	wpg_addr = WPGBbar + WPG_I2CMBUFL_OFFSET;
241 	wpg_data = readl (wpg_addr);
242 	data = swab32 (wpg_data);
243 
244 	status = (u8) data;
245 
246 	debug_polling ("%s - Exit index[%x] status[%x]\n", __FUNCTION__, index, status);
247 
248 	return (status);
249 }
250 
251 /*----------------------------------------------------------------------
252 * Name:    i2c_ctrl_write
253 *
254 * Action:  write to HPC over I2C
255 *
256 * Return   0 or error codes
257 *---------------------------------------------------------------------*/
258 static u8 i2c_ctrl_write (struct controller *ctlr_ptr, void __iomem *WPGBbar, u8 index, u8 cmd)
259 {
260 	u8 rc;
261 	void __iomem *wpg_addr;	// base addr + offset
262 	unsigned long wpg_data;	// data to/from WPG LOHI format
263 	unsigned long ultemp;
264 	unsigned long data;	// actual data HILO format
265 	int i;
266 
267 	debug_polling ("%s - Entry WPGBbar[%p] index[%x] cmd[%x]\n", __FUNCTION__, WPGBbar, index, cmd);
268 
269 	rc = 0;
270 	//--------------------------------------------------------------------
271 	// WRITE - step 1
272 	// write at address, byte length, I2C address (shifted), index
273 	// or write direct, byte length, index
274 	data = 0x00000000;
275 
276 	if (ctlr_ptr->ctlr_type == 0x02) {
277 		data = WPG_WRITEATADDR_MASK;
278 		// fill in I2C address
279 		ultemp = (unsigned long)ctlr_ptr->u.wpeg_ctlr.i2c_addr;
280 		ultemp = ultemp >> 1;
281 		data |= (ultemp << 8);
282 
283 		// fill in index
284 		data |= (unsigned long)index;
285 	} else if (ctlr_ptr->ctlr_type == 0x04) {
286 		data = WPG_WRITEDIRECT_MASK;
287 
288 		// fill in index
289 		ultemp = (unsigned long)index;
290 		ultemp = ultemp << 8;
291 		data |= ultemp;
292 	} else {
293 		err ("this controller type is not supported \n");
294 		return HPC_ERROR;
295 	}
296 
297 	wpg_data = swab32 (data);	// swap data before writing
298 	wpg_addr = WPGBbar + WPG_I2CMOSUP_OFFSET;
299 	writel (wpg_data, wpg_addr);
300 
301 	//--------------------------------------------------------------------
302 	// WRITE - step 2 : clear the message buffer
303 	data = 0x00000000 | (unsigned long)cmd;
304 	wpg_data = swab32 (data);
305 	wpg_addr = WPGBbar + WPG_I2CMBUFL_OFFSET;
306 	writel (wpg_data, wpg_addr);
307 
308 	//--------------------------------------------------------------------
309 	// WRITE - step 3 : issue start operation,I2C master control bit 30:ON
310 	//                 2020 : [20] OR operation at [20] offset 0x20
311 	data = WPG_I2CMCNTL_STARTOP_MASK;
312 	wpg_data = swab32 (data);
313 	wpg_addr = WPGBbar + WPG_I2CMCNTL_OFFSET + WPG_I2C_OR;
314 	writel (wpg_data, wpg_addr);
315 
316 	//--------------------------------------------------------------------
317 	// WRITE - step 4 : wait until start operation bit clears
318 	i = CMD_COMPLETE_TOUT_SEC;
319 	while (i) {
320 		msleep(10);
321 		wpg_addr = WPGBbar + WPG_I2CMCNTL_OFFSET;
322 		wpg_data = readl (wpg_addr);
323 		data = swab32 (wpg_data);
324 		if (!(data & WPG_I2CMCNTL_STARTOP_MASK))
325 			break;
326 		i--;
327 	}
328 	if (i == 0) {
329 		debug ("%s - Exit Error:WPG timeout\n", __FUNCTION__);
330 		rc = HPC_ERROR;
331 	}
332 
333 	//--------------------------------------------------------------------
334 	// WRITE - step 5 : read I2C status register
335 	i = CMD_COMPLETE_TOUT_SEC;
336 	while (i) {
337 		msleep(10);
338 		wpg_addr = WPGBbar + WPG_I2CSTAT_OFFSET;
339 		wpg_data = readl (wpg_addr);
340 		data = swab32 (wpg_data);
341 		if (HPC_I2CSTATUS_CHECK (data))
342 			break;
343 		i--;
344 	}
345 	if (i == 0) {
346 		debug ("ctrl_read - Error : I2C timeout\n");
347 		rc = HPC_ERROR;
348 	}
349 
350 	debug_polling ("%s Exit rc[%x]\n", __FUNCTION__, rc);
351 	return (rc);
352 }
353 
354 //------------------------------------------------------------
355 //  Read from ISA type HPC
356 //------------------------------------------------------------
357 static u8 isa_ctrl_read (struct controller *ctlr_ptr, u8 offset)
358 {
359 	u16 start_address;
360 	u16 end_address;
361 	u8 data;
362 
363 	start_address = ctlr_ptr->u.isa_ctlr.io_start;
364 	end_address = ctlr_ptr->u.isa_ctlr.io_end;
365 	data = inb (start_address + offset);
366 	return data;
367 }
368 
369 //--------------------------------------------------------------
370 // Write to ISA type HPC
371 //--------------------------------------------------------------
372 static void isa_ctrl_write (struct controller *ctlr_ptr, u8 offset, u8 data)
373 {
374 	u16 start_address;
375 	u16 port_address;
376 
377 	start_address = ctlr_ptr->u.isa_ctlr.io_start;
378 	port_address = start_address + (u16) offset;
379 	outb (data, port_address);
380 }
381 
382 static u8 pci_ctrl_read (struct controller *ctrl, u8 offset)
383 {
384 	u8 data = 0x00;
385 	debug ("inside pci_ctrl_read\n");
386 	if (ctrl->ctrl_dev)
387 		pci_read_config_byte (ctrl->ctrl_dev, HPC_PCI_OFFSET + offset, &data);
388 	return data;
389 }
390 
391 static u8 pci_ctrl_write (struct controller *ctrl, u8 offset, u8 data)
392 {
393 	u8 rc = -ENODEV;
394 	debug ("inside pci_ctrl_write\n");
395 	if (ctrl->ctrl_dev) {
396 		pci_write_config_byte (ctrl->ctrl_dev, HPC_PCI_OFFSET + offset, data);
397 		rc = 0;
398 	}
399 	return rc;
400 }
401 
402 static u8 ctrl_read (struct controller *ctlr, void __iomem *base, u8 offset)
403 {
404 	u8 rc;
405 	switch (ctlr->ctlr_type) {
406 	case 0:
407 		rc = isa_ctrl_read (ctlr, offset);
408 		break;
409 	case 1:
410 		rc = pci_ctrl_read (ctlr, offset);
411 		break;
412 	case 2:
413 	case 4:
414 		rc = i2c_ctrl_read (ctlr, base, offset);
415 		break;
416 	default:
417 		return -ENODEV;
418 	}
419 	return rc;
420 }
421 
422 static u8 ctrl_write (struct controller *ctlr, void __iomem *base, u8 offset, u8 data)
423 {
424 	u8 rc = 0;
425 	switch (ctlr->ctlr_type) {
426 	case 0:
427 		isa_ctrl_write(ctlr, offset, data);
428 		break;
429 	case 1:
430 		rc = pci_ctrl_write (ctlr, offset, data);
431 		break;
432 	case 2:
433 	case 4:
434 		rc = i2c_ctrl_write(ctlr, base, offset, data);
435 		break;
436 	default:
437 		return -ENODEV;
438 	}
439 	return rc;
440 }
441 /*----------------------------------------------------------------------
442 * Name:    hpc_writecmdtoindex()
443 *
444 * Action:  convert a write command to proper index within a controller
445 *
446 * Return   index, HPC_ERROR
447 *---------------------------------------------------------------------*/
448 static u8 hpc_writecmdtoindex (u8 cmd, u8 index)
449 {
450 	u8 rc;
451 
452 	switch (cmd) {
453 	case HPC_CTLR_ENABLEIRQ:	// 0x00.N.15
454 	case HPC_CTLR_CLEARIRQ:	// 0x06.N.15
455 	case HPC_CTLR_RESET:	// 0x07.N.15
456 	case HPC_CTLR_IRQSTEER:	// 0x08.N.15
457 	case HPC_CTLR_DISABLEIRQ:	// 0x01.N.15
458 	case HPC_ALLSLOT_ON:	// 0x11.N.15
459 	case HPC_ALLSLOT_OFF:	// 0x12.N.15
460 		rc = 0x0F;
461 		break;
462 
463 	case HPC_SLOT_OFF:	// 0x02.Y.0-14
464 	case HPC_SLOT_ON:	// 0x03.Y.0-14
465 	case HPC_SLOT_ATTNOFF:	// 0x04.N.0-14
466 	case HPC_SLOT_ATTNON:	// 0x05.N.0-14
467 	case HPC_SLOT_BLINKLED:	// 0x13.N.0-14
468 		rc = index;
469 		break;
470 
471 	case HPC_BUS_33CONVMODE:
472 	case HPC_BUS_66CONVMODE:
473 	case HPC_BUS_66PCIXMODE:
474 	case HPC_BUS_100PCIXMODE:
475 	case HPC_BUS_133PCIXMODE:
476 		rc = index + WPG_1ST_BUS_INDEX - 1;
477 		break;
478 
479 	default:
480 		err ("hpc_writecmdtoindex - Error invalid cmd[%x]\n", cmd);
481 		rc = HPC_ERROR;
482 	}
483 
484 	return rc;
485 }
486 
487 /*----------------------------------------------------------------------
488 * Name:    hpc_readcmdtoindex()
489 *
490 * Action:  convert a read command to proper index within a controller
491 *
492 * Return   index, HPC_ERROR
493 *---------------------------------------------------------------------*/
494 static u8 hpc_readcmdtoindex (u8 cmd, u8 index)
495 {
496 	u8 rc;
497 
498 	switch (cmd) {
499 	case READ_CTLRSTATUS:
500 		rc = 0x0F;
501 		break;
502 	case READ_SLOTSTATUS:
503 	case READ_ALLSTAT:
504 		rc = index;
505 		break;
506 	case READ_EXTSLOTSTATUS:
507 		rc = index + WPG_1ST_EXTSLOT_INDEX;
508 		break;
509 	case READ_BUSSTATUS:
510 		rc = index + WPG_1ST_BUS_INDEX - 1;
511 		break;
512 	case READ_SLOTLATCHLOWREG:
513 		rc = 0x28;
514 		break;
515 	case READ_REVLEVEL:
516 		rc = 0x25;
517 		break;
518 	case READ_HPCOPTIONS:
519 		rc = 0x27;
520 		break;
521 	default:
522 		rc = HPC_ERROR;
523 	}
524 	return rc;
525 }
526 
527 /*----------------------------------------------------------------------
528 * Name:    HPCreadslot()
529 *
530 * Action:  issue a READ command to HPC
531 *
532 * Input:   pslot   - can not be NULL for READ_ALLSTAT
533 *          pstatus - can be NULL for READ_ALLSTAT
534 *
535 * Return   0 or error codes
536 *---------------------------------------------------------------------*/
537 int ibmphp_hpc_readslot (struct slot * pslot, u8 cmd, u8 * pstatus)
538 {
539 	void __iomem *wpg_bbar = NULL;
540 	struct controller *ctlr_ptr;
541 	struct list_head *pslotlist;
542 	u8 index, status;
543 	int rc = 0;
544 	int busindex;
545 
546 	debug_polling ("%s - Entry pslot[%p] cmd[%x] pstatus[%p]\n", __FUNCTION__, pslot, cmd, pstatus);
547 
548 	if ((pslot == NULL)
549 	    || ((pstatus == NULL) && (cmd != READ_ALLSTAT) && (cmd != READ_BUSSTATUS))) {
550 		rc = -EINVAL;
551 		err ("%s - Error invalid pointer, rc[%d]\n", __FUNCTION__, rc);
552 		return rc;
553 	}
554 
555 	if (cmd == READ_BUSSTATUS) {
556 		busindex = ibmphp_get_bus_index (pslot->bus);
557 		if (busindex < 0) {
558 			rc = -EINVAL;
559 			err ("%s - Exit Error:invalid bus, rc[%d]\n", __FUNCTION__, rc);
560 			return rc;
561 		} else
562 			index = (u8) busindex;
563 	} else
564 		index = pslot->ctlr_index;
565 
566 	index = hpc_readcmdtoindex (cmd, index);
567 
568 	if (index == HPC_ERROR) {
569 		rc = -EINVAL;
570 		err ("%s - Exit Error:invalid index, rc[%d]\n", __FUNCTION__, rc);
571 		return rc;
572 	}
573 
574 	ctlr_ptr = pslot->ctrl;
575 
576 	get_hpc_access ();
577 
578 	//--------------------------------------------------------------------
579 	// map physical address to logical address
580 	//--------------------------------------------------------------------
581 	if ((ctlr_ptr->ctlr_type == 2) || (ctlr_ptr->ctlr_type == 4))
582 		wpg_bbar = ioremap (ctlr_ptr->u.wpeg_ctlr.wpegbbar, WPG_I2C_IOREMAP_SIZE);
583 
584 	//--------------------------------------------------------------------
585 	// check controller status before reading
586 	//--------------------------------------------------------------------
587 	rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT, ctlr_ptr, wpg_bbar, &status);
588 	if (!rc) {
589 		switch (cmd) {
590 		case READ_ALLSTAT:
591 			// update the slot structure
592 			pslot->ctrl->status = status;
593 			pslot->status = ctrl_read (ctlr_ptr, wpg_bbar, index);
594 			rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT, ctlr_ptr, wpg_bbar,
595 						       &status);
596 			if (!rc)
597 				pslot->ext_status = ctrl_read (ctlr_ptr, wpg_bbar, index + WPG_1ST_EXTSLOT_INDEX);
598 
599 			break;
600 
601 		case READ_SLOTSTATUS:
602 			// DO NOT update the slot structure
603 			*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
604 			break;
605 
606 		case READ_EXTSLOTSTATUS:
607 			// DO NOT update the slot structure
608 			*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
609 			break;
610 
611 		case READ_CTLRSTATUS:
612 			// DO NOT update the slot structure
613 			*pstatus = status;
614 			break;
615 
616 		case READ_BUSSTATUS:
617 			pslot->busstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
618 			break;
619 		case READ_REVLEVEL:
620 			*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
621 			break;
622 		case READ_HPCOPTIONS:
623 			*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
624 			break;
625 		case READ_SLOTLATCHLOWREG:
626 			// DO NOT update the slot structure
627 			*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, index);
628 			break;
629 
630 			// Not used
631 		case READ_ALLSLOT:
632 			list_for_each (pslotlist, &ibmphp_slot_head) {
633 				pslot = list_entry (pslotlist, struct slot, ibm_slot_list);
634 				index = pslot->ctlr_index;
635 				rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT, ctlr_ptr,
636 								wpg_bbar, &status);
637 				if (!rc) {
638 					pslot->status = ctrl_read (ctlr_ptr, wpg_bbar, index);
639 					rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT,
640 									ctlr_ptr, wpg_bbar, &status);
641 					if (!rc)
642 						pslot->ext_status =
643 						    ctrl_read (ctlr_ptr, wpg_bbar,
644 								index + WPG_1ST_EXTSLOT_INDEX);
645 				} else {
646 					err ("%s - Error ctrl_read failed\n", __FUNCTION__);
647 					rc = -EINVAL;
648 					break;
649 				}
650 			}
651 			break;
652 		default:
653 			rc = -EINVAL;
654 			break;
655 		}
656 	}
657 	//--------------------------------------------------------------------
658 	// cleanup
659 	//--------------------------------------------------------------------
660 
661 	// remove physical to logical address mapping
662 	if ((ctlr_ptr->ctlr_type == 2) || (ctlr_ptr->ctlr_type == 4))
663 		iounmap (wpg_bbar);
664 
665 	free_hpc_access ();
666 
667 	debug_polling ("%s - Exit rc[%d]\n", __FUNCTION__, rc);
668 	return rc;
669 }
670 
671 /*----------------------------------------------------------------------
672 * Name:    ibmphp_hpc_writeslot()
673 *
674 * Action: issue a WRITE command to HPC
675 *---------------------------------------------------------------------*/
676 int ibmphp_hpc_writeslot (struct slot * pslot, u8 cmd)
677 {
678 	void __iomem *wpg_bbar = NULL;
679 	struct controller *ctlr_ptr;
680 	u8 index, status;
681 	int busindex;
682 	u8 done;
683 	int rc = 0;
684 	int timeout;
685 
686 	debug_polling ("%s - Entry pslot[%p] cmd[%x]\n", __FUNCTION__, pslot, cmd);
687 	if (pslot == NULL) {
688 		rc = -EINVAL;
689 		err ("%s - Error Exit rc[%d]\n", __FUNCTION__, rc);
690 		return rc;
691 	}
692 
693 	if ((cmd == HPC_BUS_33CONVMODE) || (cmd == HPC_BUS_66CONVMODE) ||
694 		(cmd == HPC_BUS_66PCIXMODE) || (cmd == HPC_BUS_100PCIXMODE) ||
695 		(cmd == HPC_BUS_133PCIXMODE)) {
696 		busindex = ibmphp_get_bus_index (pslot->bus);
697 		if (busindex < 0) {
698 			rc = -EINVAL;
699 			err ("%s - Exit Error:invalid bus, rc[%d]\n", __FUNCTION__, rc);
700 			return rc;
701 		} else
702 			index = (u8) busindex;
703 	} else
704 		index = pslot->ctlr_index;
705 
706 	index = hpc_writecmdtoindex (cmd, index);
707 
708 	if (index == HPC_ERROR) {
709 		rc = -EINVAL;
710 		err ("%s - Error Exit rc[%d]\n", __FUNCTION__, rc);
711 		return rc;
712 	}
713 
714 	ctlr_ptr = pslot->ctrl;
715 
716 	get_hpc_access ();
717 
718 	//--------------------------------------------------------------------
719 	// map physical address to logical address
720 	//--------------------------------------------------------------------
721 	if ((ctlr_ptr->ctlr_type == 2) || (ctlr_ptr->ctlr_type == 4)) {
722 		wpg_bbar = ioremap (ctlr_ptr->u.wpeg_ctlr.wpegbbar, WPG_I2C_IOREMAP_SIZE);
723 
724 		debug ("%s - ctlr id[%x] physical[%lx] logical[%lx] i2c[%x]\n", __FUNCTION__,
725 		ctlr_ptr->ctlr_id, (ulong) (ctlr_ptr->u.wpeg_ctlr.wpegbbar), (ulong) wpg_bbar,
726 		ctlr_ptr->u.wpeg_ctlr.i2c_addr);
727 	}
728 	//--------------------------------------------------------------------
729 	// check controller status before writing
730 	//--------------------------------------------------------------------
731 	rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT, ctlr_ptr, wpg_bbar, &status);
732 	if (!rc) {
733 
734 		ctrl_write (ctlr_ptr, wpg_bbar, index, cmd);
735 
736 		//--------------------------------------------------------------------
737 		// check controller is still not working on the command
738 		//--------------------------------------------------------------------
739 		timeout = CMD_COMPLETE_TOUT_SEC;
740 		done = FALSE;
741 		while (!done) {
742 			rc = hpc_wait_ctlr_notworking (HPC_CTLR_WORKING_TOUT, ctlr_ptr, wpg_bbar,
743 							&status);
744 			if (!rc) {
745 				if (NEEDTOCHECK_CMDSTATUS (cmd)) {
746 					if (CTLR_FINISHED (status) == HPC_CTLR_FINISHED_YES)
747 						done = TRUE;
748 				} else
749 					done = TRUE;
750 			}
751 			if (!done) {
752 				msleep(1000);
753 				if (timeout < 1) {
754 					done = TRUE;
755 					err ("%s - Error command complete timeout\n", __FUNCTION__);
756 					rc = -EFAULT;
757 				} else
758 					timeout--;
759 			}
760 		}
761 		ctlr_ptr->status = status;
762 	}
763 	// cleanup
764 
765 	// remove physical to logical address mapping
766 	if ((ctlr_ptr->ctlr_type == 2) || (ctlr_ptr->ctlr_type == 4))
767 		iounmap (wpg_bbar);
768 	free_hpc_access ();
769 
770 	debug_polling ("%s - Exit rc[%d]\n", __FUNCTION__, rc);
771 	return rc;
772 }
773 
774 /*----------------------------------------------------------------------
775 * Name:    get_hpc_access()
776 *
777 * Action: make sure only one process can access HPC at one time
778 *---------------------------------------------------------------------*/
779 static void get_hpc_access (void)
780 {
781 	down (&sem_hpcaccess);
782 }
783 
784 /*----------------------------------------------------------------------
785 * Name:    free_hpc_access()
786 *---------------------------------------------------------------------*/
787 void free_hpc_access (void)
788 {
789 	up (&sem_hpcaccess);
790 }
791 
792 /*----------------------------------------------------------------------
793 * Name:    ibmphp_lock_operations()
794 *
795 * Action: make sure only one process can change the data structure
796 *---------------------------------------------------------------------*/
797 void ibmphp_lock_operations (void)
798 {
799 	down (&semOperations);
800 	to_debug = TRUE;
801 }
802 
803 /*----------------------------------------------------------------------
804 * Name:    ibmphp_unlock_operations()
805 *---------------------------------------------------------------------*/
806 void ibmphp_unlock_operations (void)
807 {
808 	debug ("%s - Entry\n", __FUNCTION__);
809 	up (&semOperations);
810 	to_debug = FALSE;
811 	debug ("%s - Exit\n", __FUNCTION__);
812 }
813 
814 /*----------------------------------------------------------------------
815 * Name:    poll_hpc()
816 *---------------------------------------------------------------------*/
817 #define POLL_LATCH_REGISTER	0
818 #define POLL_SLOTS		1
819 #define POLL_SLEEP		2
820 static void poll_hpc (void)
821 {
822 	struct slot myslot;
823 	struct slot *pslot = NULL;
824 	struct list_head *pslotlist;
825 	int rc;
826 	int poll_state = POLL_LATCH_REGISTER;
827 	u8 oldlatchlow = 0x00;
828 	u8 curlatchlow = 0x00;
829 	int poll_count = 0;
830 	u8 ctrl_count = 0x00;
831 
832 	debug ("%s - Entry\n", __FUNCTION__);
833 
834 	while (!ibmphp_shutdown) {
835 		if (ibmphp_shutdown)
836 			break;
837 
838 		/* try to get the lock to do some kind of hardware access */
839 		down (&semOperations);
840 
841 		switch (poll_state) {
842 		case POLL_LATCH_REGISTER:
843 			oldlatchlow = curlatchlow;
844 			ctrl_count = 0x00;
845 			list_for_each (pslotlist, &ibmphp_slot_head) {
846 				if (ctrl_count >= ibmphp_get_total_controllers())
847 					break;
848 				pslot = list_entry (pslotlist, struct slot, ibm_slot_list);
849 				if (pslot->ctrl->ctlr_relative_id == ctrl_count) {
850 					ctrl_count++;
851 					if (READ_SLOT_LATCH (pslot->ctrl)) {
852 						rc = ibmphp_hpc_readslot (pslot,
853 									  READ_SLOTLATCHLOWREG,
854 									  &curlatchlow);
855 						if (oldlatchlow != curlatchlow)
856 							process_changeinlatch (oldlatchlow,
857 									       curlatchlow,
858 									       pslot->ctrl);
859 					}
860 				}
861 			}
862 			++poll_count;
863 			poll_state = POLL_SLEEP;
864 			break;
865 		case POLL_SLOTS:
866 			list_for_each (pslotlist, &ibmphp_slot_head) {
867 				pslot = list_entry (pslotlist, struct slot, ibm_slot_list);
868 				// make a copy of the old status
869 				memcpy ((void *) &myslot, (void *) pslot,
870 					sizeof (struct slot));
871 				rc = ibmphp_hpc_readslot (pslot, READ_ALLSTAT, NULL);
872 				if ((myslot.status != pslot->status)
873 				    || (myslot.ext_status != pslot->ext_status))
874 					process_changeinstatus (pslot, &myslot);
875 			}
876 			ctrl_count = 0x00;
877 			list_for_each (pslotlist, &ibmphp_slot_head) {
878 				if (ctrl_count >= ibmphp_get_total_controllers())
879 					break;
880 				pslot = list_entry (pslotlist, struct slot, ibm_slot_list);
881 				if (pslot->ctrl->ctlr_relative_id == ctrl_count) {
882 					ctrl_count++;
883 					if (READ_SLOT_LATCH (pslot->ctrl))
884 						rc = ibmphp_hpc_readslot (pslot,
885 									  READ_SLOTLATCHLOWREG,
886 									  &curlatchlow);
887 				}
888 			}
889 			++poll_count;
890 			poll_state = POLL_SLEEP;
891 			break;
892 		case POLL_SLEEP:
893 			/* don't sleep with a lock on the hardware */
894 			up (&semOperations);
895 			msleep(POLL_INTERVAL_SEC * 1000);
896 
897 			if (ibmphp_shutdown)
898 				break;
899 
900 			down (&semOperations);
901 
902 			if (poll_count >= POLL_LATCH_CNT) {
903 				poll_count = 0;
904 				poll_state = POLL_SLOTS;
905 			} else
906 				poll_state = POLL_LATCH_REGISTER;
907 			break;
908 		}
909 		/* give up the hardware semaphore */
910 		up (&semOperations);
911 		/* sleep for a short time just for good measure */
912 		msleep(100);
913 	}
914 	up (&sem_exit);
915 	debug ("%s - Exit\n", __FUNCTION__);
916 }
917 
918 
919 /*----------------------------------------------------------------------
920 * Name:    process_changeinstatus
921 *
922 * Action:  compare old and new slot status, process the change in status
923 *
924 * Input:   pointer to slot struct, old slot struct
925 *
926 * Return   0 or error codes
927 * Value:
928 *
929 * Side
930 * Effects: None.
931 *
932 * Notes:
933 *---------------------------------------------------------------------*/
934 static int process_changeinstatus (struct slot *pslot, struct slot *poldslot)
935 {
936 	u8 status;
937 	int rc = 0;
938 	u8 disable = FALSE;
939 	u8 update = FALSE;
940 
941 	debug ("process_changeinstatus - Entry pslot[%p], poldslot[%p]\n", pslot, poldslot);
942 
943 	// bit 0 - HPC_SLOT_POWER
944 	if ((pslot->status & 0x01) != (poldslot->status & 0x01))
945 		update = TRUE;
946 
947 	// bit 1 - HPC_SLOT_CONNECT
948 	// ignore
949 
950 	// bit 2 - HPC_SLOT_ATTN
951 	if ((pslot->status & 0x04) != (poldslot->status & 0x04))
952 		update = TRUE;
953 
954 	// bit 3 - HPC_SLOT_PRSNT2
955 	// bit 4 - HPC_SLOT_PRSNT1
956 	if (((pslot->status & 0x08) != (poldslot->status & 0x08))
957 		|| ((pslot->status & 0x10) != (poldslot->status & 0x10)))
958 		update = TRUE;
959 
960 	// bit 5 - HPC_SLOT_PWRGD
961 	if ((pslot->status & 0x20) != (poldslot->status & 0x20))
962 		// OFF -> ON: ignore, ON -> OFF: disable slot
963 		if ((poldslot->status & 0x20) && (SLOT_CONNECT (poldslot->status) == HPC_SLOT_CONNECTED) && (SLOT_PRESENT (poldslot->status)))
964 			disable = TRUE;
965 
966 	// bit 6 - HPC_SLOT_BUS_SPEED
967 	// ignore
968 
969 	// bit 7 - HPC_SLOT_LATCH
970 	if ((pslot->status & 0x80) != (poldslot->status & 0x80)) {
971 		update = TRUE;
972 		// OPEN -> CLOSE
973 		if (pslot->status & 0x80) {
974 			if (SLOT_PWRGD (pslot->status)) {
975 				// power goes on and off after closing latch
976 				// check again to make sure power is still ON
977 				msleep(1000);
978 				rc = ibmphp_hpc_readslot (pslot, READ_SLOTSTATUS, &status);
979 				if (SLOT_PWRGD (status))
980 					update = TRUE;
981 				else	// overwrite power in pslot to OFF
982 					pslot->status &= ~HPC_SLOT_POWER;
983 			}
984 		}
985 		// CLOSE -> OPEN
986 		else if ((SLOT_PWRGD (poldslot->status) == HPC_SLOT_PWRGD_GOOD)
987 			&& (SLOT_CONNECT (poldslot->status) == HPC_SLOT_CONNECTED) && (SLOT_PRESENT (poldslot->status))) {
988 			disable = TRUE;
989 		}
990 		// else - ignore
991 	}
992 	// bit 4 - HPC_SLOT_BLINK_ATTN
993 	if ((pslot->ext_status & 0x08) != (poldslot->ext_status & 0x08))
994 		update = TRUE;
995 
996 	if (disable) {
997 		debug ("process_changeinstatus - disable slot\n");
998 		pslot->flag = FALSE;
999 		rc = ibmphp_do_disable_slot (pslot);
1000 	}
1001 
1002 	if (update || disable) {
1003 		ibmphp_update_slot_info (pslot);
1004 	}
1005 
1006 	debug ("%s - Exit rc[%d] disable[%x] update[%x]\n", __FUNCTION__, rc, disable, update);
1007 
1008 	return rc;
1009 }
1010 
1011 /*----------------------------------------------------------------------
1012 * Name:    process_changeinlatch
1013 *
1014 * Action:  compare old and new latch reg status, process the change
1015 *
1016 * Input:   old and current latch register status
1017 *
1018 * Return   0 or error codes
1019 * Value:
1020 *---------------------------------------------------------------------*/
1021 static int process_changeinlatch (u8 old, u8 new, struct controller *ctrl)
1022 {
1023 	struct slot myslot, *pslot;
1024 	u8 i;
1025 	u8 mask;
1026 	int rc = 0;
1027 
1028 	debug ("%s - Entry old[%x], new[%x]\n", __FUNCTION__, old, new);
1029 	// bit 0 reserved, 0 is LSB, check bit 1-6 for 6 slots
1030 
1031 	for (i = ctrl->starting_slot_num; i <= ctrl->ending_slot_num; i++) {
1032 		mask = 0x01 << i;
1033 		if ((mask & old) != (mask & new)) {
1034 			pslot = ibmphp_get_slot_from_physical_num (i);
1035 			if (pslot) {
1036 				memcpy ((void *) &myslot, (void *) pslot, sizeof (struct slot));
1037 				rc = ibmphp_hpc_readslot (pslot, READ_ALLSTAT, NULL);
1038 				debug ("%s - call process_changeinstatus for slot[%d]\n", __FUNCTION__, i);
1039 				process_changeinstatus (pslot, &myslot);
1040 			} else {
1041 				rc = -EINVAL;
1042 				err ("%s - Error bad pointer for slot[%d]\n", __FUNCTION__, i);
1043 			}
1044 		}
1045 	}
1046 	debug ("%s - Exit rc[%d]\n", __FUNCTION__, rc);
1047 	return rc;
1048 }
1049 
1050 /*----------------------------------------------------------------------
1051 * Name:    hpc_poll_thread
1052 *
1053 * Action:  polling
1054 *
1055 * Return   0
1056 * Value:
1057 *---------------------------------------------------------------------*/
1058 static int hpc_poll_thread (void *data)
1059 {
1060 	debug ("%s - Entry\n", __FUNCTION__);
1061 
1062 	daemonize("hpc_poll");
1063 	allow_signal(SIGKILL);
1064 
1065 	poll_hpc ();
1066 
1067 	tid_poll = 0;
1068 	debug ("%s - Exit\n", __FUNCTION__);
1069 	return 0;
1070 }
1071 
1072 
1073 /*----------------------------------------------------------------------
1074 * Name:    ibmphp_hpc_start_poll_thread
1075 *
1076 * Action:  start polling thread
1077 *---------------------------------------------------------------------*/
1078 int __init ibmphp_hpc_start_poll_thread (void)
1079 {
1080 	int rc = 0;
1081 
1082 	debug ("%s - Entry\n", __FUNCTION__);
1083 
1084 	tid_poll = kernel_thread (hpc_poll_thread, NULL, 0);
1085 	if (tid_poll < 0) {
1086 		err ("%s - Error, thread not started\n", __FUNCTION__);
1087 		rc = -1;
1088 	}
1089 
1090 	debug ("%s - Exit tid_poll[%d] rc[%d]\n", __FUNCTION__, tid_poll, rc);
1091 	return rc;
1092 }
1093 
1094 /*----------------------------------------------------------------------
1095 * Name:    ibmphp_hpc_stop_poll_thread
1096 *
1097 * Action:  stop polling thread and cleanup
1098 *---------------------------------------------------------------------*/
1099 void __exit ibmphp_hpc_stop_poll_thread (void)
1100 {
1101 	debug ("%s - Entry\n", __FUNCTION__);
1102 
1103 	ibmphp_shutdown = TRUE;
1104 	debug ("before locking operations \n");
1105 	ibmphp_lock_operations ();
1106 	debug ("after locking operations \n");
1107 
1108 	// wait for poll thread to exit
1109 	debug ("before sem_exit down \n");
1110 	down (&sem_exit);
1111 	debug ("after sem_exit down \n");
1112 
1113 	// cleanup
1114 	debug ("before free_hpc_access \n");
1115 	free_hpc_access ();
1116 	debug ("after free_hpc_access \n");
1117 	ibmphp_unlock_operations ();
1118 	debug ("after unlock operations \n");
1119 	up (&sem_exit);
1120 	debug ("after sem exit up\n");
1121 
1122 	debug ("%s - Exit\n", __FUNCTION__);
1123 }
1124 
1125 /*----------------------------------------------------------------------
1126 * Name:    hpc_wait_ctlr_notworking
1127 *
1128 * Action:  wait until the controller is in a not working state
1129 *
1130 * Return   0, HPC_ERROR
1131 * Value:
1132 *---------------------------------------------------------------------*/
1133 static int hpc_wait_ctlr_notworking (int timeout, struct controller *ctlr_ptr, void __iomem *wpg_bbar,
1134 				    u8 * pstatus)
1135 {
1136 	int rc = 0;
1137 	u8 done = FALSE;
1138 
1139 	debug_polling ("hpc_wait_ctlr_notworking - Entry timeout[%d]\n", timeout);
1140 
1141 	while (!done) {
1142 		*pstatus = ctrl_read (ctlr_ptr, wpg_bbar, WPG_CTLR_INDEX);
1143 		if (*pstatus == HPC_ERROR) {
1144 			rc = HPC_ERROR;
1145 			done = TRUE;
1146 		}
1147 		if (CTLR_WORKING (*pstatus) == HPC_CTLR_WORKING_NO)
1148 			done = TRUE;
1149 		if (!done) {
1150 			msleep(1000);
1151 			if (timeout < 1) {
1152 				done = TRUE;
1153 				err ("HPCreadslot - Error ctlr timeout\n");
1154 				rc = HPC_ERROR;
1155 			} else
1156 				timeout--;
1157 		}
1158 	}
1159 	debug_polling ("hpc_wait_ctlr_notworking - Exit rc[%x] status[%x]\n", rc, *pstatus);
1160 	return rc;
1161 }
1162