xref: /openbmc/linux/drivers/misc/cxl/guest.c (revision fa0a497b)
1 /*
2  * Copyright 2015 IBM Corp.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 
10 #include <linux/spinlock.h>
11 #include <linux/uaccess.h>
12 #include <linux/delay.h>
13 
14 #include "cxl.h"
15 #include "hcalls.h"
16 #include "trace.h"
17 
18 #define CXL_ERROR_DETECTED_EVENT	1
19 #define CXL_SLOT_RESET_EVENT		2
20 #define CXL_RESUME_EVENT		3
21 
22 static void pci_error_handlers(struct cxl_afu *afu,
23 				int bus_error_event,
24 				pci_channel_state_t state)
25 {
26 	struct pci_dev *afu_dev;
27 
28 	if (afu->phb == NULL)
29 		return;
30 
31 	list_for_each_entry(afu_dev, &afu->phb->bus->devices, bus_list) {
32 		if (!afu_dev->driver)
33 			continue;
34 
35 		switch (bus_error_event) {
36 		case CXL_ERROR_DETECTED_EVENT:
37 			afu_dev->error_state = state;
38 
39 			if (afu_dev->driver->err_handler &&
40 			    afu_dev->driver->err_handler->error_detected)
41 				afu_dev->driver->err_handler->error_detected(afu_dev, state);
42 		break;
43 		case CXL_SLOT_RESET_EVENT:
44 			afu_dev->error_state = state;
45 
46 			if (afu_dev->driver->err_handler &&
47 			    afu_dev->driver->err_handler->slot_reset)
48 				afu_dev->driver->err_handler->slot_reset(afu_dev);
49 		break;
50 		case CXL_RESUME_EVENT:
51 			if (afu_dev->driver->err_handler &&
52 			    afu_dev->driver->err_handler->resume)
53 				afu_dev->driver->err_handler->resume(afu_dev);
54 		break;
55 		}
56 	}
57 }
58 
59 static irqreturn_t guest_handle_psl_slice_error(struct cxl_context *ctx, u64 dsisr,
60 					u64 errstat)
61 {
62 	pr_devel("in %s\n", __func__);
63 	dev_crit(&ctx->afu->dev, "PSL ERROR STATUS: 0x%.16llx\n", errstat);
64 
65 	return cxl_ops->ack_irq(ctx, 0, errstat);
66 }
67 
68 static ssize_t guest_collect_vpd(struct cxl *adapter, struct cxl_afu *afu,
69 			void *buf, size_t len)
70 {
71 	unsigned int entries, mod;
72 	unsigned long **vpd_buf = NULL;
73 	struct sg_list *le;
74 	int rc = 0, i, tocopy;
75 	u64 out = 0;
76 
77 	if (buf == NULL)
78 		return -EINVAL;
79 
80 	/* number of entries in the list */
81 	entries = len / SG_BUFFER_SIZE;
82 	mod = len % SG_BUFFER_SIZE;
83 	if (mod)
84 		entries++;
85 
86 	if (entries > SG_MAX_ENTRIES) {
87 		entries = SG_MAX_ENTRIES;
88 		len = SG_MAX_ENTRIES * SG_BUFFER_SIZE;
89 		mod = 0;
90 	}
91 
92 	vpd_buf = kzalloc(entries * sizeof(unsigned long *), GFP_KERNEL);
93 	if (!vpd_buf)
94 		return -ENOMEM;
95 
96 	le = (struct sg_list *)get_zeroed_page(GFP_KERNEL);
97 	if (!le) {
98 		rc = -ENOMEM;
99 		goto err1;
100 	}
101 
102 	for (i = 0; i < entries; i++) {
103 		vpd_buf[i] = (unsigned long *)get_zeroed_page(GFP_KERNEL);
104 		if (!vpd_buf[i]) {
105 			rc = -ENOMEM;
106 			goto err2;
107 		}
108 		le[i].phys_addr = cpu_to_be64(virt_to_phys(vpd_buf[i]));
109 		le[i].len = cpu_to_be64(SG_BUFFER_SIZE);
110 		if ((i == (entries - 1)) && mod)
111 			le[i].len = cpu_to_be64(mod);
112 	}
113 
114 	if (adapter)
115 		rc = cxl_h_collect_vpd_adapter(adapter->guest->handle,
116 					virt_to_phys(le), entries, &out);
117 	else
118 		rc = cxl_h_collect_vpd(afu->guest->handle, 0,
119 				virt_to_phys(le), entries, &out);
120 	pr_devel("length of available (entries: %i), vpd: %#llx\n",
121 		entries, out);
122 
123 	if (!rc) {
124 		/*
125 		 * hcall returns in 'out' the size of available VPDs.
126 		 * It fills the buffer with as much data as possible.
127 		 */
128 		if (out < len)
129 			len = out;
130 		rc = len;
131 		if (out) {
132 			for (i = 0; i < entries; i++) {
133 				if (len < SG_BUFFER_SIZE)
134 					tocopy = len;
135 				else
136 					tocopy = SG_BUFFER_SIZE;
137 				memcpy(buf, vpd_buf[i], tocopy);
138 				buf += tocopy;
139 				len -= tocopy;
140 			}
141 		}
142 	}
143 err2:
144 	for (i = 0; i < entries; i++) {
145 		if (vpd_buf[i])
146 			free_page((unsigned long) vpd_buf[i]);
147 	}
148 	free_page((unsigned long) le);
149 err1:
150 	kfree(vpd_buf);
151 	return rc;
152 }
153 
154 static int guest_get_irq_info(struct cxl_context *ctx, struct cxl_irq_info *info)
155 {
156 	return cxl_h_collect_int_info(ctx->afu->guest->handle, ctx->process_token, info);
157 }
158 
159 static irqreturn_t guest_psl_irq(int irq, void *data)
160 {
161 	struct cxl_context *ctx = data;
162 	struct cxl_irq_info irq_info;
163 	int rc;
164 
165 	pr_devel("%d: received PSL interrupt %i\n", ctx->pe, irq);
166 	rc = guest_get_irq_info(ctx, &irq_info);
167 	if (rc) {
168 		WARN(1, "Unable to get IRQ info: %i\n", rc);
169 		return IRQ_HANDLED;
170 	}
171 
172 	rc = cxl_irq(irq, ctx, &irq_info);
173 	return rc;
174 }
175 
176 static int afu_read_error_state(struct cxl_afu *afu, int *state_out)
177 {
178 	u64 state;
179 	int rc = 0;
180 
181 	rc = cxl_h_read_error_state(afu->guest->handle, &state);
182 	if (!rc) {
183 		WARN_ON(state != H_STATE_NORMAL &&
184 			state != H_STATE_DISABLE &&
185 			state != H_STATE_TEMP_UNAVAILABLE &&
186 			state != H_STATE_PERM_UNAVAILABLE);
187 		*state_out = state & 0xffffffff;
188 	}
189 	return rc;
190 }
191 
192 static irqreturn_t guest_slice_irq_err(int irq, void *data)
193 {
194 	struct cxl_afu *afu = data;
195 	int rc;
196 	u64 serr;
197 
198 	WARN(irq, "CXL SLICE ERROR interrupt %i\n", irq);
199 	rc = cxl_h_get_fn_error_interrupt(afu->guest->handle, &serr);
200 	if (rc) {
201 		dev_crit(&afu->dev, "Couldn't read PSL_SERR_An: %d\n", rc);
202 		return IRQ_HANDLED;
203 	}
204 	dev_crit(&afu->dev, "PSL_SERR_An: 0x%.16llx\n", serr);
205 
206 	rc = cxl_h_ack_fn_error_interrupt(afu->guest->handle, serr);
207 	if (rc)
208 		dev_crit(&afu->dev, "Couldn't ack slice error interrupt: %d\n",
209 			rc);
210 
211 	return IRQ_HANDLED;
212 }
213 
214 
215 static int irq_alloc_range(struct cxl *adapter, int len, int *irq)
216 {
217 	int i, n;
218 	struct irq_avail *cur;
219 
220 	for (i = 0; i < adapter->guest->irq_nranges; i++) {
221 		cur = &adapter->guest->irq_avail[i];
222 		n = bitmap_find_next_zero_area(cur->bitmap, cur->range,
223 					0, len, 0);
224 		if (n < cur->range) {
225 			bitmap_set(cur->bitmap, n, len);
226 			*irq = cur->offset + n;
227 			pr_devel("guest: allocate IRQs %#x->%#x\n",
228 				*irq, *irq + len - 1);
229 
230 			return 0;
231 		}
232 	}
233 	return -ENOSPC;
234 }
235 
236 static int irq_free_range(struct cxl *adapter, int irq, int len)
237 {
238 	int i, n;
239 	struct irq_avail *cur;
240 
241 	if (len == 0)
242 		return -ENOENT;
243 
244 	for (i = 0; i < adapter->guest->irq_nranges; i++) {
245 		cur = &adapter->guest->irq_avail[i];
246 		if (irq >= cur->offset &&
247 			(irq + len) <= (cur->offset + cur->range)) {
248 			n = irq - cur->offset;
249 			bitmap_clear(cur->bitmap, n, len);
250 			pr_devel("guest: release IRQs %#x->%#x\n",
251 				irq, irq + len - 1);
252 			return 0;
253 		}
254 	}
255 	return -ENOENT;
256 }
257 
258 static int guest_reset(struct cxl *adapter)
259 {
260 	struct cxl_afu *afu = NULL;
261 	int i, rc;
262 
263 	pr_devel("Adapter reset request\n");
264 	for (i = 0; i < adapter->slices; i++) {
265 		if ((afu = adapter->afu[i])) {
266 			pci_error_handlers(afu, CXL_ERROR_DETECTED_EVENT,
267 					pci_channel_io_frozen);
268 			cxl_context_detach_all(afu);
269 		}
270 	}
271 
272 	rc = cxl_h_reset_adapter(adapter->guest->handle);
273 	for (i = 0; i < adapter->slices; i++) {
274 		if (!rc && (afu = adapter->afu[i])) {
275 			pci_error_handlers(afu, CXL_SLOT_RESET_EVENT,
276 					pci_channel_io_normal);
277 			pci_error_handlers(afu, CXL_RESUME_EVENT, 0);
278 		}
279 	}
280 	return rc;
281 }
282 
283 static int guest_alloc_one_irq(struct cxl *adapter)
284 {
285 	int irq;
286 
287 	spin_lock(&adapter->guest->irq_alloc_lock);
288 	if (irq_alloc_range(adapter, 1, &irq))
289 		irq = -ENOSPC;
290 	spin_unlock(&adapter->guest->irq_alloc_lock);
291 	return irq;
292 }
293 
294 static void guest_release_one_irq(struct cxl *adapter, int irq)
295 {
296 	spin_lock(&adapter->guest->irq_alloc_lock);
297 	irq_free_range(adapter, irq, 1);
298 	spin_unlock(&adapter->guest->irq_alloc_lock);
299 }
300 
301 static int guest_alloc_irq_ranges(struct cxl_irq_ranges *irqs,
302 				struct cxl *adapter, unsigned int num)
303 {
304 	int i, try, irq;
305 
306 	memset(irqs, 0, sizeof(struct cxl_irq_ranges));
307 
308 	spin_lock(&adapter->guest->irq_alloc_lock);
309 	for (i = 0; i < CXL_IRQ_RANGES && num; i++) {
310 		try = num;
311 		while (try) {
312 			if (irq_alloc_range(adapter, try, &irq) == 0)
313 				break;
314 			try /= 2;
315 		}
316 		if (!try)
317 			goto error;
318 		irqs->offset[i] = irq;
319 		irqs->range[i] = try;
320 		num -= try;
321 	}
322 	if (num)
323 		goto error;
324 	spin_unlock(&adapter->guest->irq_alloc_lock);
325 	return 0;
326 
327 error:
328 	for (i = 0; i < CXL_IRQ_RANGES; i++)
329 		irq_free_range(adapter, irqs->offset[i], irqs->range[i]);
330 	spin_unlock(&adapter->guest->irq_alloc_lock);
331 	return -ENOSPC;
332 }
333 
334 static void guest_release_irq_ranges(struct cxl_irq_ranges *irqs,
335 				struct cxl *adapter)
336 {
337 	int i;
338 
339 	spin_lock(&adapter->guest->irq_alloc_lock);
340 	for (i = 0; i < CXL_IRQ_RANGES; i++)
341 		irq_free_range(adapter, irqs->offset[i], irqs->range[i]);
342 	spin_unlock(&adapter->guest->irq_alloc_lock);
343 }
344 
345 static int guest_register_serr_irq(struct cxl_afu *afu)
346 {
347 	afu->err_irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
348 				      dev_name(&afu->dev));
349 	if (!afu->err_irq_name)
350 		return -ENOMEM;
351 
352 	if (!(afu->serr_virq = cxl_map_irq(afu->adapter, afu->serr_hwirq,
353 				 guest_slice_irq_err, afu, afu->err_irq_name))) {
354 		kfree(afu->err_irq_name);
355 		afu->err_irq_name = NULL;
356 		return -ENOMEM;
357 	}
358 
359 	return 0;
360 }
361 
362 static void guest_release_serr_irq(struct cxl_afu *afu)
363 {
364 	cxl_unmap_irq(afu->serr_virq, afu);
365 	cxl_ops->release_one_irq(afu->adapter, afu->serr_hwirq);
366 	kfree(afu->err_irq_name);
367 }
368 
369 static int guest_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask)
370 {
371 	return cxl_h_control_faults(ctx->afu->guest->handle, ctx->process_token,
372 				tfc >> 32, (psl_reset_mask != 0));
373 }
374 
375 static void disable_afu_irqs(struct cxl_context *ctx)
376 {
377 	irq_hw_number_t hwirq;
378 	unsigned int virq;
379 	int r, i;
380 
381 	pr_devel("Disabling AFU(%d) interrupts\n", ctx->afu->slice);
382 	for (r = 0; r < CXL_IRQ_RANGES; r++) {
383 		hwirq = ctx->irqs.offset[r];
384 		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
385 			virq = irq_find_mapping(NULL, hwirq);
386 			disable_irq(virq);
387 		}
388 	}
389 }
390 
391 static void enable_afu_irqs(struct cxl_context *ctx)
392 {
393 	irq_hw_number_t hwirq;
394 	unsigned int virq;
395 	int r, i;
396 
397 	pr_devel("Enabling AFU(%d) interrupts\n", ctx->afu->slice);
398 	for (r = 0; r < CXL_IRQ_RANGES; r++) {
399 		hwirq = ctx->irqs.offset[r];
400 		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
401 			virq = irq_find_mapping(NULL, hwirq);
402 			enable_irq(virq);
403 		}
404 	}
405 }
406 
407 static int _guest_afu_cr_readXX(int sz, struct cxl_afu *afu, int cr_idx,
408 			u64 offset, u64 *val)
409 {
410 	unsigned long cr;
411 	char c;
412 	int rc = 0;
413 
414 	if (afu->crs_len < sz)
415 		return -ENOENT;
416 
417 	if (unlikely(offset >= afu->crs_len))
418 		return -ERANGE;
419 
420 	cr = get_zeroed_page(GFP_KERNEL);
421 	if (!cr)
422 		return -ENOMEM;
423 
424 	rc = cxl_h_get_config(afu->guest->handle, cr_idx, offset,
425 			virt_to_phys((void *)cr), sz);
426 	if (rc)
427 		goto err;
428 
429 	switch (sz) {
430 	case 1:
431 		c = *((char *) cr);
432 		*val = c;
433 		break;
434 	case 2:
435 		*val = in_le16((u16 *)cr);
436 		break;
437 	case 4:
438 		*val = in_le32((unsigned *)cr);
439 		break;
440 	case 8:
441 		*val = in_le64((u64 *)cr);
442 		break;
443 	default:
444 		WARN_ON(1);
445 	}
446 err:
447 	free_page(cr);
448 	return rc;
449 }
450 
451 static int guest_afu_cr_read32(struct cxl_afu *afu, int cr_idx, u64 offset,
452 			u32 *out)
453 {
454 	int rc;
455 	u64 val;
456 
457 	rc = _guest_afu_cr_readXX(4, afu, cr_idx, offset, &val);
458 	if (!rc)
459 		*out = (u32) val;
460 	return rc;
461 }
462 
463 static int guest_afu_cr_read16(struct cxl_afu *afu, int cr_idx, u64 offset,
464 			u16 *out)
465 {
466 	int rc;
467 	u64 val;
468 
469 	rc = _guest_afu_cr_readXX(2, afu, cr_idx, offset, &val);
470 	if (!rc)
471 		*out = (u16) val;
472 	return rc;
473 }
474 
475 static int guest_afu_cr_read8(struct cxl_afu *afu, int cr_idx, u64 offset,
476 			u8 *out)
477 {
478 	int rc;
479 	u64 val;
480 
481 	rc = _guest_afu_cr_readXX(1, afu, cr_idx, offset, &val);
482 	if (!rc)
483 		*out = (u8) val;
484 	return rc;
485 }
486 
487 static int guest_afu_cr_read64(struct cxl_afu *afu, int cr_idx, u64 offset,
488 			u64 *out)
489 {
490 	return _guest_afu_cr_readXX(8, afu, cr_idx, offset, out);
491 }
492 
493 static int guest_afu_cr_write32(struct cxl_afu *afu, int cr, u64 off, u32 in)
494 {
495 	/* config record is not writable from guest */
496 	return -EPERM;
497 }
498 
499 static int guest_afu_cr_write16(struct cxl_afu *afu, int cr, u64 off, u16 in)
500 {
501 	/* config record is not writable from guest */
502 	return -EPERM;
503 }
504 
505 static int guest_afu_cr_write8(struct cxl_afu *afu, int cr, u64 off, u8 in)
506 {
507 	/* config record is not writable from guest */
508 	return -EPERM;
509 }
510 
511 static int attach_afu_directed(struct cxl_context *ctx, u64 wed, u64 amr)
512 {
513 	struct cxl_process_element_hcall *elem;
514 	struct cxl *adapter = ctx->afu->adapter;
515 	const struct cred *cred;
516 	u32 pid, idx;
517 	int rc, r, i;
518 	u64 mmio_addr, mmio_size;
519 	__be64 flags = 0;
520 
521 	/* Must be 8 byte aligned and cannot cross a 4096 byte boundary */
522 	if (!(elem = (struct cxl_process_element_hcall *)
523 			get_zeroed_page(GFP_KERNEL)))
524 		return -ENOMEM;
525 
526 	elem->version = cpu_to_be64(CXL_PROCESS_ELEMENT_VERSION);
527 	if (ctx->kernel) {
528 		pid = 0;
529 		flags |= CXL_PE_TRANSLATION_ENABLED;
530 		flags |= CXL_PE_PRIVILEGED_PROCESS;
531 		if (mfmsr() & MSR_SF)
532 			flags |= CXL_PE_64_BIT;
533 	} else {
534 		pid = current->pid;
535 		flags |= CXL_PE_PROBLEM_STATE;
536 		flags |= CXL_PE_TRANSLATION_ENABLED;
537 		if (!test_tsk_thread_flag(current, TIF_32BIT))
538 			flags |= CXL_PE_64_BIT;
539 		cred = get_current_cred();
540 		if (uid_eq(cred->euid, GLOBAL_ROOT_UID))
541 			flags |= CXL_PE_PRIVILEGED_PROCESS;
542 		put_cred(cred);
543 	}
544 	elem->flags         = cpu_to_be64(flags);
545 	elem->common.tid    = cpu_to_be32(0); /* Unused */
546 	elem->common.pid    = cpu_to_be32(pid);
547 	elem->common.csrp   = cpu_to_be64(0); /* disable */
548 	elem->common.aurp0  = cpu_to_be64(0); /* disable */
549 	elem->common.aurp1  = cpu_to_be64(0); /* disable */
550 
551 	cxl_prefault(ctx, wed);
552 
553 	elem->common.sstp0  = cpu_to_be64(ctx->sstp0);
554 	elem->common.sstp1  = cpu_to_be64(ctx->sstp1);
555 	for (r = 0; r < CXL_IRQ_RANGES; r++) {
556 		for (i = 0; i < ctx->irqs.range[r]; i++) {
557 			if (r == 0 && i == 0) {
558 				elem->pslVirtualIsn = cpu_to_be32(ctx->irqs.offset[0]);
559 			} else {
560 				idx = ctx->irqs.offset[r] + i - adapter->guest->irq_base_offset;
561 				elem->applicationVirtualIsnBitmap[idx / 8] |= 0x80 >> (idx % 8);
562 			}
563 		}
564 	}
565 	elem->common.amr = cpu_to_be64(amr);
566 	elem->common.wed = cpu_to_be64(wed);
567 
568 	disable_afu_irqs(ctx);
569 
570 	rc = cxl_h_attach_process(ctx->afu->guest->handle, elem,
571 				&ctx->process_token, &mmio_addr, &mmio_size);
572 	if (rc == H_SUCCESS) {
573 		if (ctx->master || !ctx->afu->pp_psa) {
574 			ctx->psn_phys = ctx->afu->psn_phys;
575 			ctx->psn_size = ctx->afu->adapter->ps_size;
576 		} else {
577 			ctx->psn_phys = mmio_addr;
578 			ctx->psn_size = mmio_size;
579 		}
580 		if (ctx->afu->pp_psa && mmio_size &&
581 			ctx->afu->pp_size == 0) {
582 			/*
583 			 * There's no property in the device tree to read the
584 			 * pp_size. We only find out at the 1st attach.
585 			 * Compared to bare-metal, it is too late and we
586 			 * should really lock here. However, on powerVM,
587 			 * pp_size is really only used to display in /sys.
588 			 * Being discussed with pHyp for their next release.
589 			 */
590 			ctx->afu->pp_size = mmio_size;
591 		}
592 		/* from PAPR: process element is bytes 4-7 of process token */
593 		ctx->external_pe = ctx->process_token & 0xFFFFFFFF;
594 		pr_devel("CXL pe=%i is known as %i for pHyp, mmio_size=%#llx",
595 			ctx->pe, ctx->external_pe, ctx->psn_size);
596 		ctx->pe_inserted = true;
597 		enable_afu_irqs(ctx);
598 	}
599 
600 	free_page((u64)elem);
601 	return rc;
602 }
603 
604 static int guest_attach_process(struct cxl_context *ctx, bool kernel, u64 wed, u64 amr)
605 {
606 	pr_devel("in %s\n", __func__);
607 
608 	ctx->kernel = kernel;
609 	if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
610 		return attach_afu_directed(ctx, wed, amr);
611 
612 	/* dedicated mode not supported on FW840 */
613 
614 	return -EINVAL;
615 }
616 
617 static int detach_afu_directed(struct cxl_context *ctx)
618 {
619 	if (!ctx->pe_inserted)
620 		return 0;
621 	if (cxl_h_detach_process(ctx->afu->guest->handle, ctx->process_token))
622 		return -1;
623 	return 0;
624 }
625 
626 static int guest_detach_process(struct cxl_context *ctx)
627 {
628 	pr_devel("in %s\n", __func__);
629 	trace_cxl_detach(ctx);
630 
631 	if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
632 		return -EIO;
633 
634 	if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
635 		return detach_afu_directed(ctx);
636 
637 	return -EINVAL;
638 }
639 
640 static void guest_release_afu(struct device *dev)
641 {
642 	struct cxl_afu *afu = to_cxl_afu(dev);
643 
644 	pr_devel("%s\n", __func__);
645 
646 	idr_destroy(&afu->contexts_idr);
647 
648 	kfree(afu->guest);
649 	kfree(afu);
650 }
651 
652 ssize_t cxl_guest_read_afu_vpd(struct cxl_afu *afu, void *buf, size_t len)
653 {
654 	return guest_collect_vpd(NULL, afu, buf, len);
655 }
656 
657 #define ERR_BUFF_MAX_COPY_SIZE PAGE_SIZE
658 static ssize_t guest_afu_read_err_buffer(struct cxl_afu *afu, char *buf,
659 					loff_t off, size_t count)
660 {
661 	void *tbuf = NULL;
662 	int rc = 0;
663 
664 	tbuf = (void *) get_zeroed_page(GFP_KERNEL);
665 	if (!tbuf)
666 		return -ENOMEM;
667 
668 	rc = cxl_h_get_afu_err(afu->guest->handle,
669 			       off & 0x7,
670 			       virt_to_phys(tbuf),
671 			       count);
672 	if (rc)
673 		goto err;
674 
675 	if (count > ERR_BUFF_MAX_COPY_SIZE)
676 		count = ERR_BUFF_MAX_COPY_SIZE - (off & 0x7);
677 	memcpy(buf, tbuf, count);
678 err:
679 	free_page((u64)tbuf);
680 
681 	return rc;
682 }
683 
684 static int guest_afu_check_and_enable(struct cxl_afu *afu)
685 {
686 	return 0;
687 }
688 
689 static bool guest_support_attributes(const char *attr_name,
690 				     enum cxl_attrs type)
691 {
692 	switch (type) {
693 	case CXL_ADAPTER_ATTRS:
694 		if ((strcmp(attr_name, "base_image") == 0) ||
695 			(strcmp(attr_name, "load_image_on_perst") == 0) ||
696 			(strcmp(attr_name, "perst_reloads_same_image") == 0) ||
697 			(strcmp(attr_name, "image_loaded") == 0))
698 			return false;
699 		break;
700 	case CXL_AFU_MASTER_ATTRS:
701 		if ((strcmp(attr_name, "pp_mmio_off") == 0))
702 			return false;
703 		break;
704 	case CXL_AFU_ATTRS:
705 		break;
706 	default:
707 		break;
708 	}
709 
710 	return true;
711 }
712 
713 static int activate_afu_directed(struct cxl_afu *afu)
714 {
715 	int rc;
716 
717 	dev_info(&afu->dev, "Activating AFU(%d) directed mode\n", afu->slice);
718 
719 	afu->current_mode = CXL_MODE_DIRECTED;
720 
721 	afu->num_procs = afu->max_procs_virtualised;
722 
723 	if ((rc = cxl_chardev_m_afu_add(afu)))
724 		return rc;
725 
726 	if ((rc = cxl_sysfs_afu_m_add(afu)))
727 		goto err;
728 
729 	if ((rc = cxl_chardev_s_afu_add(afu)))
730 		goto err1;
731 
732 	return 0;
733 err1:
734 	cxl_sysfs_afu_m_remove(afu);
735 err:
736 	cxl_chardev_afu_remove(afu);
737 	return rc;
738 }
739 
740 static int guest_afu_activate_mode(struct cxl_afu *afu, int mode)
741 {
742 	if (!mode)
743 		return 0;
744 	if (!(mode & afu->modes_supported))
745 		return -EINVAL;
746 
747 	if (mode == CXL_MODE_DIRECTED)
748 		return activate_afu_directed(afu);
749 
750 	if (mode == CXL_MODE_DEDICATED)
751 		dev_err(&afu->dev, "Dedicated mode not supported\n");
752 
753 	return -EINVAL;
754 }
755 
756 static int deactivate_afu_directed(struct cxl_afu *afu)
757 {
758 	dev_info(&afu->dev, "Deactivating AFU(%d) directed mode\n", afu->slice);
759 
760 	afu->current_mode = 0;
761 	afu->num_procs = 0;
762 
763 	cxl_sysfs_afu_m_remove(afu);
764 	cxl_chardev_afu_remove(afu);
765 
766 	cxl_ops->afu_reset(afu);
767 
768 	return 0;
769 }
770 
771 static int guest_afu_deactivate_mode(struct cxl_afu *afu, int mode)
772 {
773 	if (!mode)
774 		return 0;
775 	if (!(mode & afu->modes_supported))
776 		return -EINVAL;
777 
778 	if (mode == CXL_MODE_DIRECTED)
779 		return deactivate_afu_directed(afu);
780 	return 0;
781 }
782 
783 static int guest_afu_reset(struct cxl_afu *afu)
784 {
785 	pr_devel("AFU(%d) reset request\n", afu->slice);
786 	return cxl_h_reset_afu(afu->guest->handle);
787 }
788 
789 static int guest_map_slice_regs(struct cxl_afu *afu)
790 {
791 	if (!(afu->p2n_mmio = ioremap(afu->guest->p2n_phys, afu->guest->p2n_size))) {
792 		dev_err(&afu->dev, "Error mapping AFU(%d) MMIO regions\n",
793 			afu->slice);
794 		return -ENOMEM;
795 	}
796 	return 0;
797 }
798 
799 static void guest_unmap_slice_regs(struct cxl_afu *afu)
800 {
801 	if (afu->p2n_mmio)
802 		iounmap(afu->p2n_mmio);
803 }
804 
805 static int afu_update_state(struct cxl_afu *afu)
806 {
807 	int rc, cur_state;
808 
809 	rc = afu_read_error_state(afu, &cur_state);
810 	if (rc)
811 		return rc;
812 
813 	if (afu->guest->previous_state == cur_state)
814 		return 0;
815 
816 	pr_devel("AFU(%d) update state to %#x\n", afu->slice, cur_state);
817 
818 	switch (cur_state) {
819 	case H_STATE_NORMAL:
820 		afu->guest->previous_state = cur_state;
821 		rc = 1;
822 		break;
823 
824 	case H_STATE_DISABLE:
825 		pci_error_handlers(afu, CXL_ERROR_DETECTED_EVENT,
826 				pci_channel_io_frozen);
827 
828 		cxl_context_detach_all(afu);
829 		if ((rc = cxl_ops->afu_reset(afu)))
830 			pr_devel("reset hcall failed %d\n", rc);
831 
832 		rc = afu_read_error_state(afu, &cur_state);
833 		if (!rc && cur_state == H_STATE_NORMAL) {
834 			pci_error_handlers(afu, CXL_SLOT_RESET_EVENT,
835 					pci_channel_io_normal);
836 			pci_error_handlers(afu, CXL_RESUME_EVENT, 0);
837 			rc = 1;
838 		}
839 		afu->guest->previous_state = 0;
840 		break;
841 
842 	case H_STATE_TEMP_UNAVAILABLE:
843 		afu->guest->previous_state = cur_state;
844 		break;
845 
846 	case H_STATE_PERM_UNAVAILABLE:
847 		dev_err(&afu->dev, "AFU is in permanent error state\n");
848 		pci_error_handlers(afu, CXL_ERROR_DETECTED_EVENT,
849 				pci_channel_io_perm_failure);
850 		afu->guest->previous_state = cur_state;
851 		break;
852 
853 	default:
854 		pr_err("Unexpected AFU(%d) error state: %#x\n",
855 		       afu->slice, cur_state);
856 		return -EINVAL;
857 	}
858 
859 	return rc;
860 }
861 
862 static int afu_do_recovery(struct cxl_afu *afu)
863 {
864 	int rc;
865 
866 	/* many threads can arrive here, in case of detach_all for example.
867 	 * Only one needs to drive the recovery
868 	 */
869 	if (mutex_trylock(&afu->guest->recovery_lock)) {
870 		rc = afu_update_state(afu);
871 		mutex_unlock(&afu->guest->recovery_lock);
872 		return rc;
873 	}
874 	return 0;
875 }
876 
877 static bool guest_link_ok(struct cxl *cxl, struct cxl_afu *afu)
878 {
879 	int state;
880 
881 	if (afu) {
882 		if (afu_read_error_state(afu, &state) ||
883 			state != H_STATE_NORMAL) {
884 			if (afu_do_recovery(afu) > 0) {
885 				/* check again in case we've just fixed it */
886 				if (!afu_read_error_state(afu, &state) &&
887 					state == H_STATE_NORMAL)
888 					return true;
889 			}
890 			return false;
891 		}
892 	}
893 
894 	return true;
895 }
896 
897 static int afu_properties_look_ok(struct cxl_afu *afu)
898 {
899 	if (afu->pp_irqs < 0) {
900 		dev_err(&afu->dev, "Unexpected per-process minimum interrupt value\n");
901 		return -EINVAL;
902 	}
903 
904 	if (afu->max_procs_virtualised < 1) {
905 		dev_err(&afu->dev, "Unexpected max number of processes virtualised value\n");
906 		return -EINVAL;
907 	}
908 
909 	if (afu->crs_len < 0) {
910 		dev_err(&afu->dev, "Unexpected configuration record size value\n");
911 		return -EINVAL;
912 	}
913 
914 	return 0;
915 }
916 
917 int cxl_guest_init_afu(struct cxl *adapter, int slice, struct device_node *afu_np)
918 {
919 	struct cxl_afu *afu;
920 	bool free = true;
921 	int rc;
922 
923 	pr_devel("in %s - AFU(%d)\n", __func__, slice);
924 	if (!(afu = cxl_alloc_afu(adapter, slice)))
925 		return -ENOMEM;
926 
927 	if (!(afu->guest = kzalloc(sizeof(struct cxl_afu_guest), GFP_KERNEL))) {
928 		kfree(afu);
929 		return -ENOMEM;
930 	}
931 
932 	mutex_init(&afu->guest->recovery_lock);
933 
934 	if ((rc = dev_set_name(&afu->dev, "afu%i.%i",
935 					  adapter->adapter_num,
936 					  slice)))
937 		goto err1;
938 
939 	adapter->slices++;
940 
941 	if ((rc = cxl_of_read_afu_handle(afu, afu_np)))
942 		goto err1;
943 
944 	if ((rc = cxl_ops->afu_reset(afu)))
945 		goto err1;
946 
947 	if ((rc = cxl_of_read_afu_properties(afu, afu_np)))
948 		goto err1;
949 
950 	if ((rc = afu_properties_look_ok(afu)))
951 		goto err1;
952 
953 	if ((rc = guest_map_slice_regs(afu)))
954 		goto err1;
955 
956 	if ((rc = guest_register_serr_irq(afu)))
957 		goto err2;
958 
959 	/*
960 	 * After we call this function we must not free the afu directly, even
961 	 * if it returns an error!
962 	 */
963 	if ((rc = cxl_register_afu(afu)))
964 		goto err_put1;
965 
966 	if ((rc = cxl_sysfs_afu_add(afu)))
967 		goto err_put1;
968 
969 	/*
970 	 * pHyp doesn't expose the programming models supported by the
971 	 * AFU. pHyp currently only supports directed mode. If it adds
972 	 * dedicated mode later, this version of cxl has no way to
973 	 * detect it. So we'll initialize the driver, but the first
974 	 * attach will fail.
975 	 * Being discussed with pHyp to do better (likely new property)
976 	 */
977 	if (afu->max_procs_virtualised == 1)
978 		afu->modes_supported = CXL_MODE_DEDICATED;
979 	else
980 		afu->modes_supported = CXL_MODE_DIRECTED;
981 
982 	if ((rc = cxl_afu_select_best_mode(afu)))
983 		goto err_put2;
984 
985 	adapter->afu[afu->slice] = afu;
986 
987 	afu->enabled = true;
988 
989 	if ((rc = cxl_pci_vphb_add(afu)))
990 		dev_info(&afu->dev, "Can't register vPHB\n");
991 
992 	return 0;
993 
994 err_put2:
995 	cxl_sysfs_afu_remove(afu);
996 err_put1:
997 	device_unregister(&afu->dev);
998 	free = false;
999 	guest_release_serr_irq(afu);
1000 err2:
1001 	guest_unmap_slice_regs(afu);
1002 err1:
1003 	if (free) {
1004 		kfree(afu->guest);
1005 		kfree(afu);
1006 	}
1007 	return rc;
1008 }
1009 
1010 void cxl_guest_remove_afu(struct cxl_afu *afu)
1011 {
1012 	pr_devel("in %s - AFU(%d)\n", __func__, afu->slice);
1013 
1014 	if (!afu)
1015 		return;
1016 
1017 	cxl_pci_vphb_remove(afu);
1018 	cxl_sysfs_afu_remove(afu);
1019 
1020 	spin_lock(&afu->adapter->afu_list_lock);
1021 	afu->adapter->afu[afu->slice] = NULL;
1022 	spin_unlock(&afu->adapter->afu_list_lock);
1023 
1024 	cxl_context_detach_all(afu);
1025 	cxl_ops->afu_deactivate_mode(afu, afu->current_mode);
1026 	guest_release_serr_irq(afu);
1027 	guest_unmap_slice_regs(afu);
1028 
1029 	device_unregister(&afu->dev);
1030 }
1031 
1032 static void free_adapter(struct cxl *adapter)
1033 {
1034 	struct irq_avail *cur;
1035 	int i;
1036 
1037 	if (adapter->guest->irq_avail) {
1038 		for (i = 0; i < adapter->guest->irq_nranges; i++) {
1039 			cur = &adapter->guest->irq_avail[i];
1040 			kfree(cur->bitmap);
1041 		}
1042 		kfree(adapter->guest->irq_avail);
1043 	}
1044 	kfree(adapter->guest->status);
1045 	cxl_remove_adapter_nr(adapter);
1046 	kfree(adapter->guest);
1047 	kfree(adapter);
1048 }
1049 
1050 static int properties_look_ok(struct cxl *adapter)
1051 {
1052 	/* The absence of this property means that the operational
1053 	 * status is unknown or okay
1054 	 */
1055 	if (strlen(adapter->guest->status) &&
1056 	    strcmp(adapter->guest->status, "okay")) {
1057 		pr_err("ABORTING:Bad operational status of the device\n");
1058 		return -EINVAL;
1059 	}
1060 
1061 	return 0;
1062 }
1063 
1064 ssize_t cxl_guest_read_adapter_vpd(struct cxl *adapter, void *buf, size_t len)
1065 {
1066 	return guest_collect_vpd(adapter, NULL, buf, len);
1067 }
1068 
1069 void cxl_guest_remove_adapter(struct cxl *adapter)
1070 {
1071 	pr_devel("in %s\n", __func__);
1072 
1073 	cxl_sysfs_adapter_remove(adapter);
1074 
1075 	cxl_guest_remove_chardev(adapter);
1076 	device_unregister(&adapter->dev);
1077 }
1078 
1079 static void release_adapter(struct device *dev)
1080 {
1081 	free_adapter(to_cxl_adapter(dev));
1082 }
1083 
1084 struct cxl *cxl_guest_init_adapter(struct device_node *np, struct platform_device *pdev)
1085 {
1086 	struct cxl *adapter;
1087 	bool free = true;
1088 	int rc;
1089 
1090 	if (!(adapter = cxl_alloc_adapter()))
1091 		return ERR_PTR(-ENOMEM);
1092 
1093 	if (!(adapter->guest = kzalloc(sizeof(struct cxl_guest), GFP_KERNEL))) {
1094 		free_adapter(adapter);
1095 		return ERR_PTR(-ENOMEM);
1096 	}
1097 
1098 	adapter->slices = 0;
1099 	adapter->guest->pdev = pdev;
1100 	adapter->dev.parent = &pdev->dev;
1101 	adapter->dev.release = release_adapter;
1102 	dev_set_drvdata(&pdev->dev, adapter);
1103 
1104 	if ((rc = cxl_of_read_adapter_handle(adapter, np)))
1105 		goto err1;
1106 
1107 	if ((rc = cxl_of_read_adapter_properties(adapter, np)))
1108 		goto err1;
1109 
1110 	if ((rc = properties_look_ok(adapter)))
1111 		goto err1;
1112 
1113 	if ((rc = cxl_guest_add_chardev(adapter)))
1114 		goto err1;
1115 
1116 	/*
1117 	 * After we call this function we must not free the adapter directly,
1118 	 * even if it returns an error!
1119 	 */
1120 	if ((rc = cxl_register_adapter(adapter)))
1121 		goto err_put1;
1122 
1123 	if ((rc = cxl_sysfs_adapter_add(adapter)))
1124 		goto err_put1;
1125 
1126 	return adapter;
1127 
1128 err_put1:
1129 	device_unregister(&adapter->dev);
1130 	free = false;
1131 	cxl_guest_remove_chardev(adapter);
1132 err1:
1133 	if (free)
1134 		free_adapter(adapter);
1135 	return ERR_PTR(rc);
1136 }
1137 
1138 void cxl_guest_reload_module(struct cxl *adapter)
1139 {
1140 	struct platform_device *pdev;
1141 
1142 	pdev = adapter->guest->pdev;
1143 	cxl_guest_remove_adapter(adapter);
1144 
1145 	cxl_of_probe(pdev);
1146 }
1147 
1148 const struct cxl_backend_ops cxl_guest_ops = {
1149 	.module = THIS_MODULE,
1150 	.adapter_reset = guest_reset,
1151 	.alloc_one_irq = guest_alloc_one_irq,
1152 	.release_one_irq = guest_release_one_irq,
1153 	.alloc_irq_ranges = guest_alloc_irq_ranges,
1154 	.release_irq_ranges = guest_release_irq_ranges,
1155 	.setup_irq = NULL,
1156 	.handle_psl_slice_error = guest_handle_psl_slice_error,
1157 	.psl_interrupt = guest_psl_irq,
1158 	.ack_irq = guest_ack_irq,
1159 	.attach_process = guest_attach_process,
1160 	.detach_process = guest_detach_process,
1161 	.support_attributes = guest_support_attributes,
1162 	.link_ok = guest_link_ok,
1163 	.release_afu = guest_release_afu,
1164 	.afu_read_err_buffer = guest_afu_read_err_buffer,
1165 	.afu_check_and_enable = guest_afu_check_and_enable,
1166 	.afu_activate_mode = guest_afu_activate_mode,
1167 	.afu_deactivate_mode = guest_afu_deactivate_mode,
1168 	.afu_reset = guest_afu_reset,
1169 	.afu_cr_read8 = guest_afu_cr_read8,
1170 	.afu_cr_read16 = guest_afu_cr_read16,
1171 	.afu_cr_read32 = guest_afu_cr_read32,
1172 	.afu_cr_read64 = guest_afu_cr_read64,
1173 	.afu_cr_write8 = guest_afu_cr_write8,
1174 	.afu_cr_write16 = guest_afu_cr_write16,
1175 	.afu_cr_write32 = guest_afu_cr_write32,
1176 	.read_adapter_vpd = cxl_guest_read_adapter_vpd,
1177 };
1178