1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    Copyright IBM Corp. 2002
4  *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
5  *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  * Status accumulation and basic sense functions.
8  */
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 
13 #include <asm/ccwdev.h>
14 #include <asm/cio.h>
15 
16 #include "cio.h"
17 #include "cio_debug.h"
18 #include "css.h"
19 #include "device.h"
20 #include "ioasm.h"
21 #include "io_sch.h"
22 
23 /*
24  * Check for any kind of channel or interface control check but don't
25  * issue the message for the console device
26  */
27 static void
ccw_device_msg_control_check(struct ccw_device * cdev,struct irb * irb)28 ccw_device_msg_control_check(struct ccw_device *cdev, struct irb *irb)
29 {
30 	struct subchannel *sch = to_subchannel(cdev->dev.parent);
31 	char dbf_text[15];
32 
33 	if (!scsw_is_valid_cstat(&irb->scsw) ||
34 	    !(scsw_cstat(&irb->scsw) & (SCHN_STAT_CHN_DATA_CHK |
35 	      SCHN_STAT_CHN_CTRL_CHK | SCHN_STAT_INTF_CTRL_CHK)))
36 		return;
37 	CIO_MSG_EVENT(0, "Channel-Check or Interface-Control-Check "
38 		      "received"
39 		      " ... device %04x on subchannel 0.%x.%04x, dev_stat "
40 		      ": %02X sch_stat : %02X\n",
41 		      cdev->private->dev_id.devno, sch->schid.ssid,
42 		      sch->schid.sch_no,
43 		      scsw_dstat(&irb->scsw), scsw_cstat(&irb->scsw));
44 	sprintf(dbf_text, "chk%x", sch->schid.sch_no);
45 	CIO_TRACE_EVENT(0, dbf_text);
46 	CIO_HEX_EVENT(0, irb, sizeof(struct irb));
47 }
48 
49 /*
50  * Some paths became not operational (pno bit in scsw is set).
51  */
52 static void
ccw_device_path_notoper(struct ccw_device * cdev)53 ccw_device_path_notoper(struct ccw_device *cdev)
54 {
55 	struct subchannel *sch;
56 
57 	sch = to_subchannel(cdev->dev.parent);
58 	if (cio_update_schib(sch))
59 		goto doverify;
60 
61 	CIO_MSG_EVENT(0, "%s(0.%x.%04x) - path(s) %02x are "
62 		      "not operational \n", __func__,
63 		      sch->schid.ssid, sch->schid.sch_no,
64 		      sch->schib.pmcw.pnom);
65 
66 	sch->lpm &= ~sch->schib.pmcw.pnom;
67 doverify:
68 	cdev->private->flags.doverify = 1;
69 }
70 
71 /*
72  * Copy valid bits from the extended control word to device irb.
73  */
74 static void
ccw_device_accumulate_ecw(struct ccw_device * cdev,struct irb * irb)75 ccw_device_accumulate_ecw(struct ccw_device *cdev, struct irb *irb)
76 {
77 	/*
78 	 * Copy extended control bit if it is valid... yes there
79 	 * are condition that have to be met for the extended control
80 	 * bit to have meaning. Sick.
81 	 */
82 	cdev->private->irb.scsw.cmd.ectl = 0;
83 	if ((irb->scsw.cmd.stctl & SCSW_STCTL_ALERT_STATUS) &&
84 	    !(irb->scsw.cmd.stctl & SCSW_STCTL_INTER_STATUS))
85 		cdev->private->irb.scsw.cmd.ectl = irb->scsw.cmd.ectl;
86 	/* Check if extended control word is valid. */
87 	if (!cdev->private->irb.scsw.cmd.ectl)
88 		return;
89 	/* Copy concurrent sense / model dependent information. */
90 	memcpy (&cdev->private->irb.ecw, irb->ecw, sizeof (irb->ecw));
91 }
92 
93 /*
94  * Check if extended status word is valid.
95  */
96 static int
ccw_device_accumulate_esw_valid(struct irb * irb)97 ccw_device_accumulate_esw_valid(struct irb *irb)
98 {
99 	if (!irb->scsw.cmd.eswf &&
100 	    (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND))
101 		return 0;
102 	if (irb->scsw.cmd.stctl ==
103 			(SCSW_STCTL_INTER_STATUS|SCSW_STCTL_STATUS_PEND) &&
104 	    !(irb->scsw.cmd.actl & SCSW_ACTL_SUSPENDED))
105 		return 0;
106 	return 1;
107 }
108 
109 /*
110  * Copy valid bits from the extended status word to device irb.
111  */
112 static void
ccw_device_accumulate_esw(struct ccw_device * cdev,struct irb * irb)113 ccw_device_accumulate_esw(struct ccw_device *cdev, struct irb *irb)
114 {
115 	struct irb *cdev_irb;
116 	struct sublog *cdev_sublog, *sublog;
117 
118 	if (!ccw_device_accumulate_esw_valid(irb))
119 		return;
120 
121 	cdev_irb = &cdev->private->irb;
122 
123 	/* Copy last path used mask. */
124 	cdev_irb->esw.esw1.lpum = irb->esw.esw1.lpum;
125 
126 	/* Copy subchannel logout information if esw is of format 0. */
127 	if (irb->scsw.cmd.eswf) {
128 		cdev_sublog = &cdev_irb->esw.esw0.sublog;
129 		sublog = &irb->esw.esw0.sublog;
130 		/* Copy extended status flags. */
131 		cdev_sublog->esf = sublog->esf;
132 		/*
133 		 * Copy fields that have a meaning for channel data check
134 		 * channel control check and interface control check.
135 		 */
136 		if (irb->scsw.cmd.cstat & (SCHN_STAT_CHN_DATA_CHK |
137 				       SCHN_STAT_CHN_CTRL_CHK |
138 				       SCHN_STAT_INTF_CTRL_CHK)) {
139 			/* Copy ancillary report bit. */
140 			cdev_sublog->arep = sublog->arep;
141 			/* Copy field-validity-flags. */
142 			cdev_sublog->fvf = sublog->fvf;
143 			/* Copy storage access code. */
144 			cdev_sublog->sacc = sublog->sacc;
145 			/* Copy termination code. */
146 			cdev_sublog->termc = sublog->termc;
147 			/* Copy sequence code. */
148 			cdev_sublog->seqc = sublog->seqc;
149 		}
150 		/* Copy device status check. */
151 		cdev_sublog->devsc = sublog->devsc;
152 		/* Copy secondary error. */
153 		cdev_sublog->serr = sublog->serr;
154 		/* Copy i/o-error alert. */
155 		cdev_sublog->ioerr = sublog->ioerr;
156 		/* Copy channel path timeout bit. */
157 		if (irb->scsw.cmd.cstat & SCHN_STAT_INTF_CTRL_CHK)
158 			cdev_irb->esw.esw0.erw.cpt = irb->esw.esw0.erw.cpt;
159 		/* Copy failing storage address validity flag. */
160 		cdev_irb->esw.esw0.erw.fsavf = irb->esw.esw0.erw.fsavf;
161 		if (cdev_irb->esw.esw0.erw.fsavf) {
162 			/* ... and copy the failing storage address. */
163 			memcpy(cdev_irb->esw.esw0.faddr, irb->esw.esw0.faddr,
164 			       sizeof (irb->esw.esw0.faddr));
165 			/* ... and copy the failing storage address format. */
166 			cdev_irb->esw.esw0.erw.fsaf = irb->esw.esw0.erw.fsaf;
167 		}
168 		/* Copy secondary ccw address validity bit. */
169 		cdev_irb->esw.esw0.erw.scavf = irb->esw.esw0.erw.scavf;
170 		if (irb->esw.esw0.erw.scavf)
171 			/* ... and copy the secondary ccw address. */
172 			cdev_irb->esw.esw0.saddr = irb->esw.esw0.saddr;
173 
174 	}
175 	/* FIXME: DCTI for format 2? */
176 
177 	/* Copy authorization bit. */
178 	cdev_irb->esw.esw0.erw.auth = irb->esw.esw0.erw.auth;
179 	/* Copy path verification required flag. */
180 	cdev_irb->esw.esw0.erw.pvrf = irb->esw.esw0.erw.pvrf;
181 	if (irb->esw.esw0.erw.pvrf)
182 		cdev->private->flags.doverify = 1;
183 	/* Copy concurrent sense bit. */
184 	cdev_irb->esw.esw0.erw.cons = irb->esw.esw0.erw.cons;
185 	if (irb->esw.esw0.erw.cons)
186 		cdev_irb->esw.esw0.erw.scnt = irb->esw.esw0.erw.scnt;
187 }
188 
189 /*
190  * Accumulate status from irb to devstat.
191  */
192 void
ccw_device_accumulate_irb(struct ccw_device * cdev,struct irb * irb)193 ccw_device_accumulate_irb(struct ccw_device *cdev, struct irb *irb)
194 {
195 	struct irb *cdev_irb;
196 
197 	/*
198 	 * Check if the status pending bit is set in stctl.
199 	 * If not, the remaining bit have no meaning and we must ignore them.
200 	 * The esw is not meaningful as well...
201 	 */
202 	if (!(scsw_stctl(&irb->scsw) & SCSW_STCTL_STATUS_PEND))
203 		return;
204 
205 	/* Check for channel checks and interface control checks. */
206 	ccw_device_msg_control_check(cdev, irb);
207 
208 	/* Check for path not operational. */
209 	if (scsw_is_valid_pno(&irb->scsw) && scsw_pno(&irb->scsw))
210 		ccw_device_path_notoper(cdev);
211 	/* No irb accumulation for transport mode irbs. */
212 	if (scsw_is_tm(&irb->scsw)) {
213 		memcpy(&cdev->private->irb, irb, sizeof(struct irb));
214 		return;
215 	}
216 	/*
217 	 * Don't accumulate unsolicited interrupts.
218 	 */
219 	if (!scsw_is_solicited(&irb->scsw))
220 		return;
221 
222 	cdev_irb = &cdev->private->irb;
223 
224 	/*
225 	 * If the clear function had been performed, all formerly pending
226 	 * status at the subchannel has been cleared and we must not pass
227 	 * intermediate accumulated status to the device driver.
228 	 */
229 	if (irb->scsw.cmd.fctl & SCSW_FCTL_CLEAR_FUNC)
230 		memset(&cdev->private->irb, 0, sizeof(struct irb));
231 
232 	/* Copy bits which are valid only for the start function. */
233 	if (irb->scsw.cmd.fctl & SCSW_FCTL_START_FUNC) {
234 		/* Copy key. */
235 		cdev_irb->scsw.cmd.key = irb->scsw.cmd.key;
236 		/* Copy suspend control bit. */
237 		cdev_irb->scsw.cmd.sctl = irb->scsw.cmd.sctl;
238 		/* Accumulate deferred condition code. */
239 		cdev_irb->scsw.cmd.cc |= irb->scsw.cmd.cc;
240 		/* Copy ccw format bit. */
241 		cdev_irb->scsw.cmd.fmt = irb->scsw.cmd.fmt;
242 		/* Copy prefetch bit. */
243 		cdev_irb->scsw.cmd.pfch = irb->scsw.cmd.pfch;
244 		/* Copy initial-status-interruption-control. */
245 		cdev_irb->scsw.cmd.isic = irb->scsw.cmd.isic;
246 		/* Copy address limit checking control. */
247 		cdev_irb->scsw.cmd.alcc = irb->scsw.cmd.alcc;
248 		/* Copy suppress suspend bit. */
249 		cdev_irb->scsw.cmd.ssi = irb->scsw.cmd.ssi;
250 	}
251 
252 	/* Take care of the extended control bit and extended control word. */
253 	ccw_device_accumulate_ecw(cdev, irb);
254 
255 	/* Accumulate function control. */
256 	cdev_irb->scsw.cmd.fctl |= irb->scsw.cmd.fctl;
257 	/* Copy activity control. */
258 	cdev_irb->scsw.cmd.actl = irb->scsw.cmd.actl;
259 	/* Accumulate status control. */
260 	cdev_irb->scsw.cmd.stctl |= irb->scsw.cmd.stctl;
261 	/*
262 	 * Copy ccw address if it is valid. This is a bit simplified
263 	 * but should be close enough for all practical purposes.
264 	 */
265 	if ((irb->scsw.cmd.stctl & SCSW_STCTL_PRIM_STATUS) ||
266 	    ((irb->scsw.cmd.stctl ==
267 	      (SCSW_STCTL_INTER_STATUS|SCSW_STCTL_STATUS_PEND)) &&
268 	     (irb->scsw.cmd.actl & SCSW_ACTL_DEVACT) &&
269 	     (irb->scsw.cmd.actl & SCSW_ACTL_SCHACT)) ||
270 	    (irb->scsw.cmd.actl & SCSW_ACTL_SUSPENDED))
271 		cdev_irb->scsw.cmd.cpa = irb->scsw.cmd.cpa;
272 	/* Accumulate device status, but not the device busy flag. */
273 	cdev_irb->scsw.cmd.dstat &= ~DEV_STAT_BUSY;
274 	/* dstat is not always valid. */
275 	if (irb->scsw.cmd.stctl &
276 	    (SCSW_STCTL_PRIM_STATUS | SCSW_STCTL_SEC_STATUS
277 	     | SCSW_STCTL_INTER_STATUS | SCSW_STCTL_ALERT_STATUS))
278 		cdev_irb->scsw.cmd.dstat |= irb->scsw.cmd.dstat;
279 	/* Accumulate subchannel status. */
280 	cdev_irb->scsw.cmd.cstat |= irb->scsw.cmd.cstat;
281 	/* Copy residual count if it is valid. */
282 	if ((irb->scsw.cmd.stctl & SCSW_STCTL_PRIM_STATUS) &&
283 	    (irb->scsw.cmd.cstat & ~(SCHN_STAT_PCI | SCHN_STAT_INCORR_LEN))
284 	     == 0)
285 		cdev_irb->scsw.cmd.count = irb->scsw.cmd.count;
286 
287 	/* Take care of bits in the extended status word. */
288 	ccw_device_accumulate_esw(cdev, irb);
289 
290 	/*
291 	 * Check whether we must issue a SENSE CCW ourselves if there is no
292 	 * concurrent sense facility installed for the subchannel.
293 	 * No sense is required if no delayed sense is pending
294 	 * and we did not get a unit check without sense information.
295 	 *
296 	 * Note: We should check for ioinfo[irq]->flags.consns but VM
297 	 *	 violates the ESA/390 architecture and doesn't present an
298 	 *	 operand exception for virtual devices without concurrent
299 	 *	 sense facility available/supported when enabling the
300 	 *	 concurrent sense facility.
301 	 */
302 	if ((cdev_irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
303 	    !(cdev_irb->esw.esw0.erw.cons))
304 		cdev->private->flags.dosense = 1;
305 }
306 
307 /*
308  * Do a basic sense.
309  */
310 int
ccw_device_do_sense(struct ccw_device * cdev,struct irb * irb)311 ccw_device_do_sense(struct ccw_device *cdev, struct irb *irb)
312 {
313 	struct subchannel *sch;
314 	struct ccw1 *sense_ccw;
315 	int rc;
316 
317 	sch = to_subchannel(cdev->dev.parent);
318 
319 	/* A sense is required, can we do it now ? */
320 	if (scsw_actl(&irb->scsw) & (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT))
321 		/*
322 		 * we received an Unit Check but we have no final
323 		 *  status yet, therefore we must delay the SENSE
324 		 *  processing. We must not report this intermediate
325 		 *  status to the device interrupt handler.
326 		 */
327 		return -EBUSY;
328 
329 	/*
330 	 * We have ending status but no sense information. Do a basic sense.
331 	 */
332 	sense_ccw = &to_io_private(sch)->sense_ccw;
333 	sense_ccw->cmd_code = CCW_CMD_BASIC_SENSE;
334 	sense_ccw->cda = (__u32) __pa(cdev->private->irb.ecw);
335 	sense_ccw->count = SENSE_MAX_COUNT;
336 	sense_ccw->flags = CCW_FLAG_SLI;
337 
338 	rc = cio_start(sch, sense_ccw, 0xff);
339 	if (rc == -ENODEV || rc == -EACCES)
340 		dev_fsm_event(cdev, DEV_EVENT_VERIFY);
341 	return rc;
342 }
343 
344 /*
345  * Add information from basic sense to devstat.
346  */
347 void
ccw_device_accumulate_basic_sense(struct ccw_device * cdev,struct irb * irb)348 ccw_device_accumulate_basic_sense(struct ccw_device *cdev, struct irb *irb)
349 {
350 	/*
351 	 * Check if the status pending bit is set in stctl.
352 	 * If not, the remaining bit have no meaning and we must ignore them.
353 	 * The esw is not meaningful as well...
354 	 */
355 	if (!(scsw_stctl(&irb->scsw) & SCSW_STCTL_STATUS_PEND))
356 		return;
357 
358 	/* Check for channel checks and interface control checks. */
359 	ccw_device_msg_control_check(cdev, irb);
360 
361 	/* Check for path not operational. */
362 	if (scsw_is_valid_pno(&irb->scsw) && scsw_pno(&irb->scsw))
363 		ccw_device_path_notoper(cdev);
364 
365 	if (!(irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
366 	    (irb->scsw.cmd.dstat & DEV_STAT_CHN_END)) {
367 		cdev->private->irb.esw.esw0.erw.cons = 1;
368 		cdev->private->flags.dosense = 0;
369 	}
370 	/* Check if path verification is required. */
371 	if (ccw_device_accumulate_esw_valid(irb) &&
372 	    irb->esw.esw0.erw.pvrf)
373 		cdev->private->flags.doverify = 1;
374 }
375 
376 /*
377  * This function accumulates the status into the private devstat and
378  * starts a basic sense if one is needed.
379  */
380 int
ccw_device_accumulate_and_sense(struct ccw_device * cdev,struct irb * irb)381 ccw_device_accumulate_and_sense(struct ccw_device *cdev, struct irb *irb)
382 {
383 	ccw_device_accumulate_irb(cdev, irb);
384 	if ((irb->scsw.cmd.actl  & (SCSW_ACTL_DEVACT | SCSW_ACTL_SCHACT)) != 0)
385 		return -EBUSY;
386 	/* Check for basic sense. */
387 	if (cdev->private->flags.dosense &&
388 	    !(irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)) {
389 		cdev->private->irb.esw.esw0.erw.cons = 1;
390 		cdev->private->flags.dosense = 0;
391 		return 0;
392 	}
393 	if (cdev->private->flags.dosense) {
394 		ccw_device_do_sense(cdev, irb);
395 		return -EBUSY;
396 	}
397 	return 0;
398 }
399 
400