xref: /openbmc/linux/drivers/misc/cxl/native.c (revision 9cfc5c90)
1 /*
2  * Copyright 2014 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/sched.h>
12 #include <linux/slab.h>
13 #include <linux/sched.h>
14 #include <linux/mutex.h>
15 #include <linux/mm.h>
16 #include <linux/uaccess.h>
17 #include <asm/synch.h>
18 #include <misc/cxl-base.h>
19 
20 #include "cxl.h"
21 #include "trace.h"
22 
23 static int afu_control(struct cxl_afu *afu, u64 command,
24 		       u64 result, u64 mask, bool enabled)
25 {
26 	u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
27 	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
28 	int rc = 0;
29 
30 	spin_lock(&afu->afu_cntl_lock);
31 	pr_devel("AFU command starting: %llx\n", command);
32 
33 	trace_cxl_afu_ctrl(afu, command);
34 
35 	cxl_p2n_write(afu, CXL_AFU_Cntl_An, AFU_Cntl | command);
36 
37 	AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
38 	while ((AFU_Cntl & mask) != result) {
39 		if (time_after_eq(jiffies, timeout)) {
40 			dev_warn(&afu->dev, "WARNING: AFU control timed out!\n");
41 			rc = -EBUSY;
42 			goto out;
43 		}
44 
45 		if (!cxl_adapter_link_ok(afu->adapter)) {
46 			afu->enabled = enabled;
47 			rc = -EIO;
48 			goto out;
49 		}
50 
51 		pr_devel_ratelimited("AFU control... (0x%016llx)\n",
52 				     AFU_Cntl | command);
53 		cpu_relax();
54 		AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
55 	};
56 	pr_devel("AFU command complete: %llx\n", command);
57 	afu->enabled = enabled;
58 out:
59 	trace_cxl_afu_ctrl_done(afu, command, rc);
60 	spin_unlock(&afu->afu_cntl_lock);
61 
62 	return rc;
63 }
64 
65 static int afu_enable(struct cxl_afu *afu)
66 {
67 	pr_devel("AFU enable request\n");
68 
69 	return afu_control(afu, CXL_AFU_Cntl_An_E,
70 			   CXL_AFU_Cntl_An_ES_Enabled,
71 			   CXL_AFU_Cntl_An_ES_MASK, true);
72 }
73 
74 int cxl_afu_disable(struct cxl_afu *afu)
75 {
76 	pr_devel("AFU disable request\n");
77 
78 	return afu_control(afu, 0, CXL_AFU_Cntl_An_ES_Disabled,
79 			   CXL_AFU_Cntl_An_ES_MASK, false);
80 }
81 
82 /* This will disable as well as reset */
83 int __cxl_afu_reset(struct cxl_afu *afu)
84 {
85 	pr_devel("AFU reset request\n");
86 
87 	return afu_control(afu, CXL_AFU_Cntl_An_RA,
88 			   CXL_AFU_Cntl_An_RS_Complete | CXL_AFU_Cntl_An_ES_Disabled,
89 			   CXL_AFU_Cntl_An_RS_MASK | CXL_AFU_Cntl_An_ES_MASK,
90 			   false);
91 }
92 
93 int cxl_afu_check_and_enable(struct cxl_afu *afu)
94 {
95 	if (!cxl_adapter_link_ok(afu->adapter)) {
96 		WARN(1, "Refusing to enable afu while link down!\n");
97 		return -EIO;
98 	}
99 	if (afu->enabled)
100 		return 0;
101 	return afu_enable(afu);
102 }
103 
104 int cxl_psl_purge(struct cxl_afu *afu)
105 {
106 	u64 PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
107 	u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
108 	u64 dsisr, dar;
109 	u64 start, end;
110 	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
111 	int rc = 0;
112 
113 	trace_cxl_psl_ctrl(afu, CXL_PSL_SCNTL_An_Pc);
114 
115 	pr_devel("PSL purge request\n");
116 
117 	if (!cxl_adapter_link_ok(afu->adapter)) {
118 		dev_warn(&afu->dev, "PSL Purge called with link down, ignoring\n");
119 		rc = -EIO;
120 		goto out;
121 	}
122 
123 	if ((AFU_Cntl & CXL_AFU_Cntl_An_ES_MASK) != CXL_AFU_Cntl_An_ES_Disabled) {
124 		WARN(1, "psl_purge request while AFU not disabled!\n");
125 		cxl_afu_disable(afu);
126 	}
127 
128 	cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
129 		       PSL_CNTL | CXL_PSL_SCNTL_An_Pc);
130 	start = local_clock();
131 	PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
132 	while ((PSL_CNTL &  CXL_PSL_SCNTL_An_Ps_MASK)
133 			== CXL_PSL_SCNTL_An_Ps_Pending) {
134 		if (time_after_eq(jiffies, timeout)) {
135 			dev_warn(&afu->dev, "WARNING: PSL Purge timed out!\n");
136 			rc = -EBUSY;
137 			goto out;
138 		}
139 		if (!cxl_adapter_link_ok(afu->adapter)) {
140 			rc = -EIO;
141 			goto out;
142 		}
143 
144 		dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
145 		pr_devel_ratelimited("PSL purging... PSL_CNTL: 0x%016llx  PSL_DSISR: 0x%016llx\n", PSL_CNTL, dsisr);
146 		if (dsisr & CXL_PSL_DSISR_TRANS) {
147 			dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
148 			dev_notice(&afu->dev, "PSL purge terminating pending translation, DSISR: 0x%016llx, DAR: 0x%016llx\n", dsisr, dar);
149 			cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
150 		} else if (dsisr) {
151 			dev_notice(&afu->dev, "PSL purge acknowledging pending non-translation fault, DSISR: 0x%016llx\n", dsisr);
152 			cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);
153 		} else {
154 			cpu_relax();
155 		}
156 		PSL_CNTL = cxl_p1n_read(afu, CXL_PSL_SCNTL_An);
157 	};
158 	end = local_clock();
159 	pr_devel("PSL purged in %lld ns\n", end - start);
160 
161 	cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
162 		       PSL_CNTL & ~CXL_PSL_SCNTL_An_Pc);
163 out:
164 	trace_cxl_psl_ctrl_done(afu, CXL_PSL_SCNTL_An_Pc, rc);
165 	return rc;
166 }
167 
168 static int spa_max_procs(int spa_size)
169 {
170 	/*
171 	 * From the CAIA:
172 	 *    end_of_SPA_area = SPA_Base + ((n+4) * 128) + (( ((n*8) + 127) >> 7) * 128) + 255
173 	 * Most of that junk is really just an overly-complicated way of saying
174 	 * the last 256 bytes are __aligned(128), so it's really:
175 	 *    end_of_SPA_area = end_of_PSL_queue_area + __aligned(128) 255
176 	 * and
177 	 *    end_of_PSL_queue_area = SPA_Base + ((n+4) * 128) + (n*8) - 1
178 	 * so
179 	 *    sizeof(SPA) = ((n+4) * 128) + (n*8) + __aligned(128) 256
180 	 * Ignore the alignment (which is safe in this case as long as we are
181 	 * careful with our rounding) and solve for n:
182 	 */
183 	return ((spa_size / 8) - 96) / 17;
184 }
185 
186 int cxl_alloc_spa(struct cxl_afu *afu)
187 {
188 	/* Work out how many pages to allocate */
189 	afu->spa_order = 0;
190 	do {
191 		afu->spa_order++;
192 		afu->spa_size = (1 << afu->spa_order) * PAGE_SIZE;
193 		afu->spa_max_procs = spa_max_procs(afu->spa_size);
194 	} while (afu->spa_max_procs < afu->num_procs);
195 
196 	WARN_ON(afu->spa_size > 0x100000); /* Max size supported by the hardware */
197 
198 	if (!(afu->spa = (struct cxl_process_element *)
199 	      __get_free_pages(GFP_KERNEL | __GFP_ZERO, afu->spa_order))) {
200 		pr_err("cxl_alloc_spa: Unable to allocate scheduled process area\n");
201 		return -ENOMEM;
202 	}
203 	pr_devel("spa pages: %i afu->spa_max_procs: %i   afu->num_procs: %i\n",
204 		 1<<afu->spa_order, afu->spa_max_procs, afu->num_procs);
205 
206 	return 0;
207 }
208 
209 static void attach_spa(struct cxl_afu *afu)
210 {
211 	u64 spap;
212 
213 	afu->sw_command_status = (__be64 *)((char *)afu->spa +
214 					    ((afu->spa_max_procs + 3) * 128));
215 
216 	spap = virt_to_phys(afu->spa) & CXL_PSL_SPAP_Addr;
217 	spap |= ((afu->spa_size >> (12 - CXL_PSL_SPAP_Size_Shift)) - 1) & CXL_PSL_SPAP_Size;
218 	spap |= CXL_PSL_SPAP_V;
219 	pr_devel("cxl: SPA allocated at 0x%p. Max processes: %i, sw_command_status: 0x%p CXL_PSL_SPAP_An=0x%016llx\n", afu->spa, afu->spa_max_procs, afu->sw_command_status, spap);
220 	cxl_p1n_write(afu, CXL_PSL_SPAP_An, spap);
221 }
222 
223 static inline void detach_spa(struct cxl_afu *afu)
224 {
225 	cxl_p1n_write(afu, CXL_PSL_SPAP_An, 0);
226 }
227 
228 void cxl_release_spa(struct cxl_afu *afu)
229 {
230 	if (afu->spa) {
231 		free_pages((unsigned long) afu->spa, afu->spa_order);
232 		afu->spa = NULL;
233 	}
234 }
235 
236 int cxl_tlb_slb_invalidate(struct cxl *adapter)
237 {
238 	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
239 
240 	pr_devel("CXL adapter wide TLBIA & SLBIA\n");
241 
242 	cxl_p1_write(adapter, CXL_PSL_AFUSEL, CXL_PSL_AFUSEL_A);
243 
244 	cxl_p1_write(adapter, CXL_PSL_TLBIA, CXL_TLB_SLB_IQ_ALL);
245 	while (cxl_p1_read(adapter, CXL_PSL_TLBIA) & CXL_TLB_SLB_P) {
246 		if (time_after_eq(jiffies, timeout)) {
247 			dev_warn(&adapter->dev, "WARNING: CXL adapter wide TLBIA timed out!\n");
248 			return -EBUSY;
249 		}
250 		if (!cxl_adapter_link_ok(adapter))
251 			return -EIO;
252 		cpu_relax();
253 	}
254 
255 	cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_ALL);
256 	while (cxl_p1_read(adapter, CXL_PSL_SLBIA) & CXL_TLB_SLB_P) {
257 		if (time_after_eq(jiffies, timeout)) {
258 			dev_warn(&adapter->dev, "WARNING: CXL adapter wide SLBIA timed out!\n");
259 			return -EBUSY;
260 		}
261 		if (!cxl_adapter_link_ok(adapter))
262 			return -EIO;
263 		cpu_relax();
264 	}
265 	return 0;
266 }
267 
268 int cxl_afu_slbia(struct cxl_afu *afu)
269 {
270 	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
271 
272 	pr_devel("cxl_afu_slbia issuing SLBIA command\n");
273 	cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL);
274 	while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) {
275 		if (time_after_eq(jiffies, timeout)) {
276 			dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n");
277 			return -EBUSY;
278 		}
279 		/* If the adapter has gone down, we can assume that we
280 		 * will PERST it and that will invalidate everything.
281 		 */
282 		if (!cxl_adapter_link_ok(afu->adapter))
283 			return -EIO;
284 		cpu_relax();
285 	}
286 	return 0;
287 }
288 
289 static int cxl_write_sstp(struct cxl_afu *afu, u64 sstp0, u64 sstp1)
290 {
291 	int rc;
292 
293 	/* 1. Disable SSTP by writing 0 to SSTP1[V] */
294 	cxl_p2n_write(afu, CXL_SSTP1_An, 0);
295 
296 	/* 2. Invalidate all SLB entries */
297 	if ((rc = cxl_afu_slbia(afu)))
298 		return rc;
299 
300 	/* 3. Set SSTP0_An */
301 	cxl_p2n_write(afu, CXL_SSTP0_An, sstp0);
302 
303 	/* 4. Set SSTP1_An */
304 	cxl_p2n_write(afu, CXL_SSTP1_An, sstp1);
305 
306 	return 0;
307 }
308 
309 /* Using per slice version may improve performance here. (ie. SLBIA_An) */
310 static void slb_invalid(struct cxl_context *ctx)
311 {
312 	struct cxl *adapter = ctx->afu->adapter;
313 	u64 slbia;
314 
315 	WARN_ON(!mutex_is_locked(&ctx->afu->spa_mutex));
316 
317 	cxl_p1_write(adapter, CXL_PSL_LBISEL,
318 			((u64)be32_to_cpu(ctx->elem->common.pid) << 32) |
319 			be32_to_cpu(ctx->elem->lpid));
320 	cxl_p1_write(adapter, CXL_PSL_SLBIA, CXL_TLB_SLB_IQ_LPIDPID);
321 
322 	while (1) {
323 		if (!cxl_adapter_link_ok(adapter))
324 			break;
325 		slbia = cxl_p1_read(adapter, CXL_PSL_SLBIA);
326 		if (!(slbia & CXL_TLB_SLB_P))
327 			break;
328 		cpu_relax();
329 	}
330 }
331 
332 static int do_process_element_cmd(struct cxl_context *ctx,
333 				  u64 cmd, u64 pe_state)
334 {
335 	u64 state;
336 	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
337 	int rc = 0;
338 
339 	trace_cxl_llcmd(ctx, cmd);
340 
341 	WARN_ON(!ctx->afu->enabled);
342 
343 	ctx->elem->software_state = cpu_to_be32(pe_state);
344 	smp_wmb();
345 	*(ctx->afu->sw_command_status) = cpu_to_be64(cmd | 0 | ctx->pe);
346 	smp_mb();
347 	cxl_p1n_write(ctx->afu, CXL_PSL_LLCMD_An, cmd | ctx->pe);
348 	while (1) {
349 		if (time_after_eq(jiffies, timeout)) {
350 			dev_warn(&ctx->afu->dev, "WARNING: Process Element Command timed out!\n");
351 			rc = -EBUSY;
352 			goto out;
353 		}
354 		if (!cxl_adapter_link_ok(ctx->afu->adapter)) {
355 			dev_warn(&ctx->afu->dev, "WARNING: Device link down, aborting Process Element Command!\n");
356 			rc = -EIO;
357 			goto out;
358 		}
359 		state = be64_to_cpup(ctx->afu->sw_command_status);
360 		if (state == ~0ULL) {
361 			pr_err("cxl: Error adding process element to AFU\n");
362 			rc = -1;
363 			goto out;
364 		}
365 		if ((state & (CXL_SPA_SW_CMD_MASK | CXL_SPA_SW_STATE_MASK  | CXL_SPA_SW_LINK_MASK)) ==
366 		    (cmd | (cmd >> 16) | ctx->pe))
367 			break;
368 		/*
369 		 * The command won't finish in the PSL if there are
370 		 * outstanding DSIs.  Hence we need to yield here in
371 		 * case there are outstanding DSIs that we need to
372 		 * service.  Tuning possiblity: we could wait for a
373 		 * while before sched
374 		 */
375 		schedule();
376 
377 	}
378 out:
379 	trace_cxl_llcmd_done(ctx, cmd, rc);
380 	return rc;
381 }
382 
383 static int add_process_element(struct cxl_context *ctx)
384 {
385 	int rc = 0;
386 
387 	mutex_lock(&ctx->afu->spa_mutex);
388 	pr_devel("%s Adding pe: %i started\n", __func__, ctx->pe);
389 	if (!(rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_ADD, CXL_PE_SOFTWARE_STATE_V)))
390 		ctx->pe_inserted = true;
391 	pr_devel("%s Adding pe: %i finished\n", __func__, ctx->pe);
392 	mutex_unlock(&ctx->afu->spa_mutex);
393 	return rc;
394 }
395 
396 static int terminate_process_element(struct cxl_context *ctx)
397 {
398 	int rc = 0;
399 
400 	/* fast path terminate if it's already invalid */
401 	if (!(ctx->elem->software_state & cpu_to_be32(CXL_PE_SOFTWARE_STATE_V)))
402 		return rc;
403 
404 	mutex_lock(&ctx->afu->spa_mutex);
405 	pr_devel("%s Terminate pe: %i started\n", __func__, ctx->pe);
406 	/* We could be asked to terminate when the hw is down. That
407 	 * should always succeed: it's not running if the hw has gone
408 	 * away and is being reset.
409 	 */
410 	if (cxl_adapter_link_ok(ctx->afu->adapter))
411 		rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_TERMINATE,
412 					    CXL_PE_SOFTWARE_STATE_V | CXL_PE_SOFTWARE_STATE_T);
413 	ctx->elem->software_state = 0;	/* Remove Valid bit */
414 	pr_devel("%s Terminate pe: %i finished\n", __func__, ctx->pe);
415 	mutex_unlock(&ctx->afu->spa_mutex);
416 	return rc;
417 }
418 
419 static int remove_process_element(struct cxl_context *ctx)
420 {
421 	int rc = 0;
422 
423 	mutex_lock(&ctx->afu->spa_mutex);
424 	pr_devel("%s Remove pe: %i started\n", __func__, ctx->pe);
425 
426 	/* We could be asked to remove when the hw is down. Again, if
427 	 * the hw is down, the PE is gone, so we succeed.
428 	 */
429 	if (cxl_adapter_link_ok(ctx->afu->adapter))
430 		rc = do_process_element_cmd(ctx, CXL_SPA_SW_CMD_REMOVE, 0);
431 
432 	if (!rc)
433 		ctx->pe_inserted = false;
434 	slb_invalid(ctx);
435 	pr_devel("%s Remove pe: %i finished\n", __func__, ctx->pe);
436 	mutex_unlock(&ctx->afu->spa_mutex);
437 
438 	return rc;
439 }
440 
441 
442 void cxl_assign_psn_space(struct cxl_context *ctx)
443 {
444 	if (!ctx->afu->pp_size || ctx->master) {
445 		ctx->psn_phys = ctx->afu->psn_phys;
446 		ctx->psn_size = ctx->afu->adapter->ps_size;
447 	} else {
448 		ctx->psn_phys = ctx->afu->psn_phys +
449 			(ctx->afu->pp_offset + ctx->afu->pp_size * ctx->pe);
450 		ctx->psn_size = ctx->afu->pp_size;
451 	}
452 }
453 
454 static int activate_afu_directed(struct cxl_afu *afu)
455 {
456 	int rc;
457 
458 	dev_info(&afu->dev, "Activating AFU directed mode\n");
459 
460 	afu->num_procs = afu->max_procs_virtualised;
461 	if (afu->spa == NULL) {
462 		if (cxl_alloc_spa(afu))
463 			return -ENOMEM;
464 	}
465 	attach_spa(afu);
466 
467 	cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_AFU);
468 	cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
469 	cxl_p1n_write(afu, CXL_PSL_ID_An, CXL_PSL_ID_An_F | CXL_PSL_ID_An_L);
470 
471 	afu->current_mode = CXL_MODE_DIRECTED;
472 
473 	if ((rc = cxl_chardev_m_afu_add(afu)))
474 		return rc;
475 
476 	if ((rc = cxl_sysfs_afu_m_add(afu)))
477 		goto err;
478 
479 	if ((rc = cxl_chardev_s_afu_add(afu)))
480 		goto err1;
481 
482 	return 0;
483 err1:
484 	cxl_sysfs_afu_m_remove(afu);
485 err:
486 	cxl_chardev_afu_remove(afu);
487 	return rc;
488 }
489 
490 #ifdef CONFIG_CPU_LITTLE_ENDIAN
491 #define set_endian(sr) ((sr) |= CXL_PSL_SR_An_LE)
492 #else
493 #define set_endian(sr) ((sr) &= ~(CXL_PSL_SR_An_LE))
494 #endif
495 
496 static u64 calculate_sr(struct cxl_context *ctx)
497 {
498 	u64 sr = 0;
499 
500 	if (ctx->master)
501 		sr |= CXL_PSL_SR_An_MP;
502 	if (mfspr(SPRN_LPCR) & LPCR_TC)
503 		sr |= CXL_PSL_SR_An_TC;
504 	if (ctx->kernel) {
505 		sr |= CXL_PSL_SR_An_R | (mfmsr() & MSR_SF);
506 		sr |= CXL_PSL_SR_An_HV;
507 	} else {
508 		sr |= CXL_PSL_SR_An_PR | CXL_PSL_SR_An_R;
509 		set_endian(sr);
510 		sr &= ~(CXL_PSL_SR_An_HV);
511 		if (!test_tsk_thread_flag(current, TIF_32BIT))
512 			sr |= CXL_PSL_SR_An_SF;
513 	}
514 	return sr;
515 }
516 
517 static int attach_afu_directed(struct cxl_context *ctx, u64 wed, u64 amr)
518 {
519 	u32 pid;
520 	int r, result;
521 
522 	cxl_assign_psn_space(ctx);
523 
524 	ctx->elem->ctxtime = 0; /* disable */
525 	ctx->elem->lpid = cpu_to_be32(mfspr(SPRN_LPID));
526 	ctx->elem->haurp = 0; /* disable */
527 	ctx->elem->sdr = cpu_to_be64(mfspr(SPRN_SDR1));
528 
529 	pid = current->pid;
530 	if (ctx->kernel)
531 		pid = 0;
532 	ctx->elem->common.tid = 0;
533 	ctx->elem->common.pid = cpu_to_be32(pid);
534 
535 	ctx->elem->sr = cpu_to_be64(calculate_sr(ctx));
536 
537 	ctx->elem->common.csrp = 0; /* disable */
538 	ctx->elem->common.aurp0 = 0; /* disable */
539 	ctx->elem->common.aurp1 = 0; /* disable */
540 
541 	cxl_prefault(ctx, wed);
542 
543 	ctx->elem->common.sstp0 = cpu_to_be64(ctx->sstp0);
544 	ctx->elem->common.sstp1 = cpu_to_be64(ctx->sstp1);
545 
546 	for (r = 0; r < CXL_IRQ_RANGES; r++) {
547 		ctx->elem->ivte_offsets[r] = cpu_to_be16(ctx->irqs.offset[r]);
548 		ctx->elem->ivte_ranges[r] = cpu_to_be16(ctx->irqs.range[r]);
549 	}
550 
551 	ctx->elem->common.amr = cpu_to_be64(amr);
552 	ctx->elem->common.wed = cpu_to_be64(wed);
553 
554 	/* first guy needs to enable */
555 	if ((result = cxl_afu_check_and_enable(ctx->afu)))
556 		return result;
557 
558 	return add_process_element(ctx);
559 }
560 
561 static int deactivate_afu_directed(struct cxl_afu *afu)
562 {
563 	dev_info(&afu->dev, "Deactivating AFU directed mode\n");
564 
565 	afu->current_mode = 0;
566 	afu->num_procs = 0;
567 
568 	cxl_sysfs_afu_m_remove(afu);
569 	cxl_chardev_afu_remove(afu);
570 
571 	__cxl_afu_reset(afu);
572 	cxl_afu_disable(afu);
573 	cxl_psl_purge(afu);
574 
575 	return 0;
576 }
577 
578 static int activate_dedicated_process(struct cxl_afu *afu)
579 {
580 	dev_info(&afu->dev, "Activating dedicated process mode\n");
581 
582 	cxl_p1n_write(afu, CXL_PSL_SCNTL_An, CXL_PSL_SCNTL_An_PM_Process);
583 
584 	cxl_p1n_write(afu, CXL_PSL_CtxTime_An, 0); /* disable */
585 	cxl_p1n_write(afu, CXL_PSL_SPAP_An, 0);    /* disable */
586 	cxl_p1n_write(afu, CXL_PSL_AMOR_An, 0xFFFFFFFFFFFFFFFFULL);
587 	cxl_p1n_write(afu, CXL_PSL_LPID_An, mfspr(SPRN_LPID));
588 	cxl_p1n_write(afu, CXL_HAURP_An, 0);       /* disable */
589 	cxl_p1n_write(afu, CXL_PSL_SDR_An, mfspr(SPRN_SDR1));
590 
591 	cxl_p2n_write(afu, CXL_CSRP_An, 0);        /* disable */
592 	cxl_p2n_write(afu, CXL_AURP0_An, 0);       /* disable */
593 	cxl_p2n_write(afu, CXL_AURP1_An, 0);       /* disable */
594 
595 	afu->current_mode = CXL_MODE_DEDICATED;
596 	afu->num_procs = 1;
597 
598 	return cxl_chardev_d_afu_add(afu);
599 }
600 
601 static int attach_dedicated(struct cxl_context *ctx, u64 wed, u64 amr)
602 {
603 	struct cxl_afu *afu = ctx->afu;
604 	u64 pid;
605 	int rc;
606 
607 	pid = (u64)current->pid << 32;
608 	if (ctx->kernel)
609 		pid = 0;
610 	cxl_p2n_write(afu, CXL_PSL_PID_TID_An, pid);
611 
612 	cxl_p1n_write(afu, CXL_PSL_SR_An, calculate_sr(ctx));
613 
614 	if ((rc = cxl_write_sstp(afu, ctx->sstp0, ctx->sstp1)))
615 		return rc;
616 
617 	cxl_prefault(ctx, wed);
618 
619 	cxl_p1n_write(afu, CXL_PSL_IVTE_Offset_An,
620 		       (((u64)ctx->irqs.offset[0] & 0xffff) << 48) |
621 		       (((u64)ctx->irqs.offset[1] & 0xffff) << 32) |
622 		       (((u64)ctx->irqs.offset[2] & 0xffff) << 16) |
623 			((u64)ctx->irqs.offset[3] & 0xffff));
624 	cxl_p1n_write(afu, CXL_PSL_IVTE_Limit_An, (u64)
625 		       (((u64)ctx->irqs.range[0] & 0xffff) << 48) |
626 		       (((u64)ctx->irqs.range[1] & 0xffff) << 32) |
627 		       (((u64)ctx->irqs.range[2] & 0xffff) << 16) |
628 			((u64)ctx->irqs.range[3] & 0xffff));
629 
630 	cxl_p2n_write(afu, CXL_PSL_AMR_An, amr);
631 
632 	/* master only context for dedicated */
633 	cxl_assign_psn_space(ctx);
634 
635 	if ((rc = __cxl_afu_reset(afu)))
636 		return rc;
637 
638 	cxl_p2n_write(afu, CXL_PSL_WED_An, wed);
639 
640 	return afu_enable(afu);
641 }
642 
643 static int deactivate_dedicated_process(struct cxl_afu *afu)
644 {
645 	dev_info(&afu->dev, "Deactivating dedicated process mode\n");
646 
647 	afu->current_mode = 0;
648 	afu->num_procs = 0;
649 
650 	cxl_chardev_afu_remove(afu);
651 
652 	return 0;
653 }
654 
655 int _cxl_afu_deactivate_mode(struct cxl_afu *afu, int mode)
656 {
657 	if (mode == CXL_MODE_DIRECTED)
658 		return deactivate_afu_directed(afu);
659 	if (mode == CXL_MODE_DEDICATED)
660 		return deactivate_dedicated_process(afu);
661 	return 0;
662 }
663 
664 int cxl_afu_deactivate_mode(struct cxl_afu *afu)
665 {
666 	return _cxl_afu_deactivate_mode(afu, afu->current_mode);
667 }
668 
669 int cxl_afu_activate_mode(struct cxl_afu *afu, int mode)
670 {
671 	if (!mode)
672 		return 0;
673 	if (!(mode & afu->modes_supported))
674 		return -EINVAL;
675 
676 	if (!cxl_adapter_link_ok(afu->adapter)) {
677 		WARN(1, "Device link is down, refusing to activate!\n");
678 		return -EIO;
679 	}
680 
681 	if (mode == CXL_MODE_DIRECTED)
682 		return activate_afu_directed(afu);
683 	if (mode == CXL_MODE_DEDICATED)
684 		return activate_dedicated_process(afu);
685 
686 	return -EINVAL;
687 }
688 
689 int cxl_attach_process(struct cxl_context *ctx, bool kernel, u64 wed, u64 amr)
690 {
691 	if (!cxl_adapter_link_ok(ctx->afu->adapter)) {
692 		WARN(1, "Device link is down, refusing to attach process!\n");
693 		return -EIO;
694 	}
695 
696 	ctx->kernel = kernel;
697 	if (ctx->afu->current_mode == CXL_MODE_DIRECTED)
698 		return attach_afu_directed(ctx, wed, amr);
699 
700 	if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
701 		return attach_dedicated(ctx, wed, amr);
702 
703 	return -EINVAL;
704 }
705 
706 static inline int detach_process_native_dedicated(struct cxl_context *ctx)
707 {
708 	__cxl_afu_reset(ctx->afu);
709 	cxl_afu_disable(ctx->afu);
710 	cxl_psl_purge(ctx->afu);
711 	return 0;
712 }
713 
714 static inline int detach_process_native_afu_directed(struct cxl_context *ctx)
715 {
716 	if (!ctx->pe_inserted)
717 		return 0;
718 	if (terminate_process_element(ctx))
719 		return -1;
720 	if (remove_process_element(ctx))
721 		return -1;
722 
723 	return 0;
724 }
725 
726 int cxl_detach_process(struct cxl_context *ctx)
727 {
728 	trace_cxl_detach(ctx);
729 
730 	if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
731 		return detach_process_native_dedicated(ctx);
732 
733 	return detach_process_native_afu_directed(ctx);
734 }
735 
736 int cxl_get_irq(struct cxl_afu *afu, struct cxl_irq_info *info)
737 {
738 	u64 pidtid;
739 
740 	/* If the adapter has gone away, we can't get any meaningful
741 	 * information.
742 	 */
743 	if (!cxl_adapter_link_ok(afu->adapter))
744 		return -EIO;
745 
746 	info->dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
747 	info->dar = cxl_p2n_read(afu, CXL_PSL_DAR_An);
748 	info->dsr = cxl_p2n_read(afu, CXL_PSL_DSR_An);
749 	pidtid = cxl_p2n_read(afu, CXL_PSL_PID_TID_An);
750 	info->pid = pidtid >> 32;
751 	info->tid = pidtid & 0xffffffff;
752 	info->afu_err = cxl_p2n_read(afu, CXL_AFU_ERR_An);
753 	info->errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
754 
755 	return 0;
756 }
757 
758 static void recover_psl_err(struct cxl_afu *afu, u64 errstat)
759 {
760 	u64 dsisr;
761 
762 	pr_devel("RECOVERING FROM PSL ERROR... (0x%016llx)\n", errstat);
763 
764 	/* Clear PSL_DSISR[PE] */
765 	dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
766 	cxl_p2n_write(afu, CXL_PSL_DSISR_An, dsisr & ~CXL_PSL_DSISR_An_PE);
767 
768 	/* Write 1s to clear error status bits */
769 	cxl_p2n_write(afu, CXL_PSL_ErrStat_An, errstat);
770 }
771 
772 int cxl_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask)
773 {
774 	trace_cxl_psl_irq_ack(ctx, tfc);
775 	if (tfc)
776 		cxl_p2n_write(ctx->afu, CXL_PSL_TFC_An, tfc);
777 	if (psl_reset_mask)
778 		recover_psl_err(ctx->afu, psl_reset_mask);
779 
780 	return 0;
781 }
782 
783 int cxl_check_error(struct cxl_afu *afu)
784 {
785 	return (cxl_p1n_read(afu, CXL_PSL_SCNTL_An) == ~0ULL);
786 }
787