xref: /openbmc/linux/drivers/iommu/intel/debugfs.c (revision d47a97bd) 
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright © 2018 Intel Corporation.
4  *
5  * Authors: Gayatri Kammela <gayatri.kammela@intel.com>
6  *	    Sohil Mehta <sohil.mehta@intel.com>
7  *	    Jacob Pan <jacob.jun.pan@linux.intel.com>
8  *	    Lu Baolu <baolu.lu@linux.intel.com>
9  */
10 
11 #include <linux/debugfs.h>
12 #include <linux/dmar.h>
13 #include <linux/pci.h>
14 
15 #include <asm/irq_remapping.h>
16 
17 #include "iommu.h"
18 #include "pasid.h"
19 #include "perf.h"
20 
21 struct tbl_walk {
22 	u16 bus;
23 	u16 devfn;
24 	u32 pasid;
25 	struct root_entry *rt_entry;
26 	struct context_entry *ctx_entry;
27 	struct pasid_entry *pasid_tbl_entry;
28 };
29 
30 struct iommu_regset {
31 	int offset;
32 	const char *regs;
33 };
34 
35 #define DEBUG_BUFFER_SIZE	1024
36 static char debug_buf[DEBUG_BUFFER_SIZE];
37 
38 #define IOMMU_REGSET_ENTRY(_reg_)					\
39 	{ DMAR_##_reg_##_REG, __stringify(_reg_) }
40 
41 static const struct iommu_regset iommu_regs_32[] = {
42 	IOMMU_REGSET_ENTRY(VER),
43 	IOMMU_REGSET_ENTRY(GCMD),
44 	IOMMU_REGSET_ENTRY(GSTS),
45 	IOMMU_REGSET_ENTRY(FSTS),
46 	IOMMU_REGSET_ENTRY(FECTL),
47 	IOMMU_REGSET_ENTRY(FEDATA),
48 	IOMMU_REGSET_ENTRY(FEADDR),
49 	IOMMU_REGSET_ENTRY(FEUADDR),
50 	IOMMU_REGSET_ENTRY(PMEN),
51 	IOMMU_REGSET_ENTRY(PLMBASE),
52 	IOMMU_REGSET_ENTRY(PLMLIMIT),
53 	IOMMU_REGSET_ENTRY(ICS),
54 	IOMMU_REGSET_ENTRY(PRS),
55 	IOMMU_REGSET_ENTRY(PECTL),
56 	IOMMU_REGSET_ENTRY(PEDATA),
57 	IOMMU_REGSET_ENTRY(PEADDR),
58 	IOMMU_REGSET_ENTRY(PEUADDR),
59 };
60 
61 static const struct iommu_regset iommu_regs_64[] = {
62 	IOMMU_REGSET_ENTRY(CAP),
63 	IOMMU_REGSET_ENTRY(ECAP),
64 	IOMMU_REGSET_ENTRY(RTADDR),
65 	IOMMU_REGSET_ENTRY(CCMD),
66 	IOMMU_REGSET_ENTRY(AFLOG),
67 	IOMMU_REGSET_ENTRY(PHMBASE),
68 	IOMMU_REGSET_ENTRY(PHMLIMIT),
69 	IOMMU_REGSET_ENTRY(IQH),
70 	IOMMU_REGSET_ENTRY(IQT),
71 	IOMMU_REGSET_ENTRY(IQA),
72 	IOMMU_REGSET_ENTRY(IRTA),
73 	IOMMU_REGSET_ENTRY(PQH),
74 	IOMMU_REGSET_ENTRY(PQT),
75 	IOMMU_REGSET_ENTRY(PQA),
76 	IOMMU_REGSET_ENTRY(MTRRCAP),
77 	IOMMU_REGSET_ENTRY(MTRRDEF),
78 	IOMMU_REGSET_ENTRY(MTRR_FIX64K_00000),
79 	IOMMU_REGSET_ENTRY(MTRR_FIX16K_80000),
80 	IOMMU_REGSET_ENTRY(MTRR_FIX16K_A0000),
81 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_C0000),
82 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_C8000),
83 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_D0000),
84 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_D8000),
85 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_E0000),
86 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_E8000),
87 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_F0000),
88 	IOMMU_REGSET_ENTRY(MTRR_FIX4K_F8000),
89 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE0),
90 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK0),
91 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE1),
92 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK1),
93 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE2),
94 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK2),
95 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE3),
96 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK3),
97 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE4),
98 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK4),
99 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE5),
100 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK5),
101 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE6),
102 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK6),
103 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE7),
104 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK7),
105 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE8),
106 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK8),
107 	IOMMU_REGSET_ENTRY(MTRR_PHYSBASE9),
108 	IOMMU_REGSET_ENTRY(MTRR_PHYSMASK9),
109 	IOMMU_REGSET_ENTRY(VCCAP),
110 	IOMMU_REGSET_ENTRY(VCMD),
111 	IOMMU_REGSET_ENTRY(VCRSP),
112 };
113 
114 static int iommu_regset_show(struct seq_file *m, void *unused)
115 {
116 	struct dmar_drhd_unit *drhd;
117 	struct intel_iommu *iommu;
118 	unsigned long flag;
119 	int i, ret = 0;
120 	u64 value;
121 
122 	rcu_read_lock();
123 	for_each_active_iommu(iommu, drhd) {
124 		if (!drhd->reg_base_addr) {
125 			seq_puts(m, "IOMMU: Invalid base address\n");
126 			ret = -EINVAL;
127 			goto out;
128 		}
129 
130 		seq_printf(m, "IOMMU: %s Register Base Address: %llx\n",
131 			   iommu->name, drhd->reg_base_addr);
132 		seq_puts(m, "Name\t\t\tOffset\t\tContents\n");
133 		/*
134 		 * Publish the contents of the 64-bit hardware registers
135 		 * by adding the offset to the pointer (virtual address).
136 		 */
137 		raw_spin_lock_irqsave(&iommu->register_lock, flag);
138 		for (i = 0 ; i < ARRAY_SIZE(iommu_regs_32); i++) {
139 			value = dmar_readl(iommu->reg + iommu_regs_32[i].offset);
140 			seq_printf(m, "%-16s\t0x%02x\t\t0x%016llx\n",
141 				   iommu_regs_32[i].regs, iommu_regs_32[i].offset,
142 				   value);
143 		}
144 		for (i = 0 ; i < ARRAY_SIZE(iommu_regs_64); i++) {
145 			value = dmar_readq(iommu->reg + iommu_regs_64[i].offset);
146 			seq_printf(m, "%-16s\t0x%02x\t\t0x%016llx\n",
147 				   iommu_regs_64[i].regs, iommu_regs_64[i].offset,
148 				   value);
149 		}
150 		raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
151 		seq_putc(m, '\n');
152 	}
153 out:
154 	rcu_read_unlock();
155 
156 	return ret;
157 }
158 DEFINE_SHOW_ATTRIBUTE(iommu_regset);
159 
160 static inline void print_tbl_walk(struct seq_file *m)
161 {
162 	struct tbl_walk *tbl_wlk = m->private;
163 
164 	seq_printf(m, "%02x:%02x.%x\t0x%016llx:0x%016llx\t0x%016llx:0x%016llx\t",
165 		   tbl_wlk->bus, PCI_SLOT(tbl_wlk->devfn),
166 		   PCI_FUNC(tbl_wlk->devfn), tbl_wlk->rt_entry->hi,
167 		   tbl_wlk->rt_entry->lo, tbl_wlk->ctx_entry->hi,
168 		   tbl_wlk->ctx_entry->lo);
169 
170 	/*
171 	 * A legacy mode DMAR doesn't support PASID, hence default it to -1
172 	 * indicating that it's invalid. Also, default all PASID related fields
173 	 * to 0.
174 	 */
175 	if (!tbl_wlk->pasid_tbl_entry)
176 		seq_printf(m, "%-6d\t0x%016llx:0x%016llx:0x%016llx\n", -1,
177 			   (u64)0, (u64)0, (u64)0);
178 	else
179 		seq_printf(m, "%-6d\t0x%016llx:0x%016llx:0x%016llx\n",
180 			   tbl_wlk->pasid, tbl_wlk->pasid_tbl_entry->val[2],
181 			   tbl_wlk->pasid_tbl_entry->val[1],
182 			   tbl_wlk->pasid_tbl_entry->val[0]);
183 }
184 
185 static void pasid_tbl_walk(struct seq_file *m, struct pasid_entry *tbl_entry,
186 			   u16 dir_idx)
187 {
188 	struct tbl_walk *tbl_wlk = m->private;
189 	u8 tbl_idx;
190 
191 	for (tbl_idx = 0; tbl_idx < PASID_TBL_ENTRIES; tbl_idx++) {
192 		if (pasid_pte_is_present(tbl_entry)) {
193 			tbl_wlk->pasid_tbl_entry = tbl_entry;
194 			tbl_wlk->pasid = (dir_idx << PASID_PDE_SHIFT) + tbl_idx;
195 			print_tbl_walk(m);
196 		}
197 
198 		tbl_entry++;
199 	}
200 }
201 
202 static void pasid_dir_walk(struct seq_file *m, u64 pasid_dir_ptr,
203 			   u16 pasid_dir_size)
204 {
205 	struct pasid_dir_entry *dir_entry = phys_to_virt(pasid_dir_ptr);
206 	struct pasid_entry *pasid_tbl;
207 	u16 dir_idx;
208 
209 	for (dir_idx = 0; dir_idx < pasid_dir_size; dir_idx++) {
210 		pasid_tbl = get_pasid_table_from_pde(dir_entry);
211 		if (pasid_tbl)
212 			pasid_tbl_walk(m, pasid_tbl, dir_idx);
213 
214 		dir_entry++;
215 	}
216 }
217 
218 static void ctx_tbl_walk(struct seq_file *m, struct intel_iommu *iommu, u16 bus)
219 {
220 	struct context_entry *context;
221 	u16 devfn, pasid_dir_size;
222 	u64 pasid_dir_ptr;
223 
224 	for (devfn = 0; devfn < 256; devfn++) {
225 		struct tbl_walk tbl_wlk = {0};
226 
227 		/*
228 		 * Scalable mode root entry points to upper scalable mode
229 		 * context table and lower scalable mode context table. Each
230 		 * scalable mode context table has 128 context entries where as
231 		 * legacy mode context table has 256 context entries. So in
232 		 * scalable mode, the context entries for former 128 devices are
233 		 * in the lower scalable mode context table, while the latter
234 		 * 128 devices are in the upper scalable mode context table.
235 		 * In scalable mode, when devfn > 127, iommu_context_addr()
236 		 * automatically refers to upper scalable mode context table and
237 		 * hence the caller doesn't have to worry about differences
238 		 * between scalable mode and non scalable mode.
239 		 */
240 		context = iommu_context_addr(iommu, bus, devfn, 0);
241 		if (!context)
242 			return;
243 
244 		if (!context_present(context))
245 			continue;
246 
247 		tbl_wlk.bus = bus;
248 		tbl_wlk.devfn = devfn;
249 		tbl_wlk.rt_entry = &iommu->root_entry[bus];
250 		tbl_wlk.ctx_entry = context;
251 		m->private = &tbl_wlk;
252 
253 		if (dmar_readq(iommu->reg + DMAR_RTADDR_REG) & DMA_RTADDR_SMT) {
254 			pasid_dir_ptr = context->lo & VTD_PAGE_MASK;
255 			pasid_dir_size = get_pasid_dir_size(context);
256 			pasid_dir_walk(m, pasid_dir_ptr, pasid_dir_size);
257 			continue;
258 		}
259 
260 		print_tbl_walk(m);
261 	}
262 }
263 
264 static void root_tbl_walk(struct seq_file *m, struct intel_iommu *iommu)
265 {
266 	u16 bus;
267 
268 	spin_lock(&iommu->lock);
269 	seq_printf(m, "IOMMU %s: Root Table Address: 0x%llx\n", iommu->name,
270 		   (u64)virt_to_phys(iommu->root_entry));
271 	seq_puts(m, "B.D.F\tRoot_entry\t\t\t\tContext_entry\t\t\t\tPASID\tPASID_table_entry\n");
272 
273 	/*
274 	 * No need to check if the root entry is present or not because
275 	 * iommu_context_addr() performs the same check before returning
276 	 * context entry.
277 	 */
278 	for (bus = 0; bus < 256; bus++)
279 		ctx_tbl_walk(m, iommu, bus);
280 	spin_unlock(&iommu->lock);
281 }
282 
283 static int dmar_translation_struct_show(struct seq_file *m, void *unused)
284 {
285 	struct dmar_drhd_unit *drhd;
286 	struct intel_iommu *iommu;
287 	u32 sts;
288 
289 	rcu_read_lock();
290 	for_each_active_iommu(iommu, drhd) {
291 		sts = dmar_readl(iommu->reg + DMAR_GSTS_REG);
292 		if (!(sts & DMA_GSTS_TES)) {
293 			seq_printf(m, "DMA Remapping is not enabled on %s\n",
294 				   iommu->name);
295 			continue;
296 		}
297 		root_tbl_walk(m, iommu);
298 		seq_putc(m, '\n');
299 	}
300 	rcu_read_unlock();
301 
302 	return 0;
303 }
304 DEFINE_SHOW_ATTRIBUTE(dmar_translation_struct);
305 
306 static inline unsigned long level_to_directory_size(int level)
307 {
308 	return BIT_ULL(VTD_PAGE_SHIFT + VTD_STRIDE_SHIFT * (level - 1));
309 }
310 
311 static inline void
312 dump_page_info(struct seq_file *m, unsigned long iova, u64 *path)
313 {
314 	seq_printf(m, "0x%013lx |\t0x%016llx\t0x%016llx\t0x%016llx\t0x%016llx\t0x%016llx\n",
315 		   iova >> VTD_PAGE_SHIFT, path[5], path[4],
316 		   path[3], path[2], path[1]);
317 }
318 
319 static void pgtable_walk_level(struct seq_file *m, struct dma_pte *pde,
320 			       int level, unsigned long start,
321 			       u64 *path)
322 {
323 	int i;
324 
325 	if (level > 5 || level < 1)
326 		return;
327 
328 	for (i = 0; i < BIT_ULL(VTD_STRIDE_SHIFT);
329 			i++, pde++, start += level_to_directory_size(level)) {
330 		if (!dma_pte_present(pde))
331 			continue;
332 
333 		path[level] = pde->val;
334 		if (dma_pte_superpage(pde) || level == 1)
335 			dump_page_info(m, start, path);
336 		else
337 			pgtable_walk_level(m, phys_to_virt(dma_pte_addr(pde)),
338 					   level - 1, start, path);
339 		path[level] = 0;
340 	}
341 }
342 
343 static int __show_device_domain_translation(struct device *dev, void *data)
344 {
345 	struct dmar_domain *domain;
346 	struct seq_file *m = data;
347 	u64 path[6] = { 0 };
348 
349 	domain = to_dmar_domain(iommu_get_domain_for_dev(dev));
350 	if (!domain)
351 		return 0;
352 
353 	seq_printf(m, "Device %s @0x%llx\n", dev_name(dev),
354 		   (u64)virt_to_phys(domain->pgd));
355 	seq_puts(m, "IOVA_PFN\t\tPML5E\t\t\tPML4E\t\t\tPDPE\t\t\tPDE\t\t\tPTE\n");
356 
357 	pgtable_walk_level(m, domain->pgd, domain->agaw + 2, 0, path);
358 	seq_putc(m, '\n');
359 
360 	/* Don't iterate */
361 	return 1;
362 }
363 
364 static int show_device_domain_translation(struct device *dev, void *data)
365 {
366 	struct iommu_group *group;
367 
368 	group = iommu_group_get(dev);
369 	if (group) {
370 		/*
371 		 * The group->mutex is held across the callback, which will
372 		 * block calls to iommu_attach/detach_group/device. Hence,
373 		 * the domain of the device will not change during traversal.
374 		 *
375 		 * All devices in an iommu group share a single domain, hence
376 		 * we only dump the domain of the first device. Even though,
377 		 * this code still possibly races with the iommu_unmap()
378 		 * interface. This could be solved by RCU-freeing the page
379 		 * table pages in the iommu_unmap() path.
380 		 */
381 		iommu_group_for_each_dev(group, data,
382 					 __show_device_domain_translation);
383 		iommu_group_put(group);
384 	}
385 
386 	return 0;
387 }
388 
389 static int domain_translation_struct_show(struct seq_file *m, void *unused)
390 {
391 	return bus_for_each_dev(&pci_bus_type, NULL, m,
392 				show_device_domain_translation);
393 }
394 DEFINE_SHOW_ATTRIBUTE(domain_translation_struct);
395 
396 static void invalidation_queue_entry_show(struct seq_file *m,
397 					  struct intel_iommu *iommu)
398 {
399 	int index, shift = qi_shift(iommu);
400 	struct qi_desc *desc;
401 	int offset;
402 
403 	if (ecap_smts(iommu->ecap))
404 		seq_puts(m, "Index\t\tqw0\t\t\tqw1\t\t\tqw2\t\t\tqw3\t\t\tstatus\n");
405 	else
406 		seq_puts(m, "Index\t\tqw0\t\t\tqw1\t\t\tstatus\n");
407 
408 	for (index = 0; index < QI_LENGTH; index++) {
409 		offset = index << shift;
410 		desc = iommu->qi->desc + offset;
411 		if (ecap_smts(iommu->ecap))
412 			seq_printf(m, "%5d\t%016llx\t%016llx\t%016llx\t%016llx\t%016x\n",
413 				   index, desc->qw0, desc->qw1,
414 				   desc->qw2, desc->qw3,
415 				   iommu->qi->desc_status[index]);
416 		else
417 			seq_printf(m, "%5d\t%016llx\t%016llx\t%016x\n",
418 				   index, desc->qw0, desc->qw1,
419 				   iommu->qi->desc_status[index]);
420 	}
421 }
422 
423 static int invalidation_queue_show(struct seq_file *m, void *unused)
424 {
425 	struct dmar_drhd_unit *drhd;
426 	struct intel_iommu *iommu;
427 	unsigned long flags;
428 	struct q_inval *qi;
429 	int shift;
430 
431 	rcu_read_lock();
432 	for_each_active_iommu(iommu, drhd) {
433 		qi = iommu->qi;
434 		shift = qi_shift(iommu);
435 
436 		if (!qi || !ecap_qis(iommu->ecap))
437 			continue;
438 
439 		seq_printf(m, "Invalidation queue on IOMMU: %s\n", iommu->name);
440 
441 		raw_spin_lock_irqsave(&qi->q_lock, flags);
442 		seq_printf(m, " Base: 0x%llx\tHead: %lld\tTail: %lld\n",
443 			   (u64)virt_to_phys(qi->desc),
444 			   dmar_readq(iommu->reg + DMAR_IQH_REG) >> shift,
445 			   dmar_readq(iommu->reg + DMAR_IQT_REG) >> shift);
446 		invalidation_queue_entry_show(m, iommu);
447 		raw_spin_unlock_irqrestore(&qi->q_lock, flags);
448 		seq_putc(m, '\n');
449 	}
450 	rcu_read_unlock();
451 
452 	return 0;
453 }
454 DEFINE_SHOW_ATTRIBUTE(invalidation_queue);
455 
456 #ifdef CONFIG_IRQ_REMAP
457 static void ir_tbl_remap_entry_show(struct seq_file *m,
458 				    struct intel_iommu *iommu)
459 {
460 	struct irte *ri_entry;
461 	unsigned long flags;
462 	int idx;
463 
464 	seq_puts(m, " Entry SrcID   DstID    Vct IRTE_high\t\tIRTE_low\n");
465 
466 	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
467 	for (idx = 0; idx < INTR_REMAP_TABLE_ENTRIES; idx++) {
468 		ri_entry = &iommu->ir_table->base[idx];
469 		if (!ri_entry->present || ri_entry->p_pst)
470 			continue;
471 
472 		seq_printf(m, " %-5d %02x:%02x.%01x %08x %02x  %016llx\t%016llx\n",
473 			   idx, PCI_BUS_NUM(ri_entry->sid),
474 			   PCI_SLOT(ri_entry->sid), PCI_FUNC(ri_entry->sid),
475 			   ri_entry->dest_id, ri_entry->vector,
476 			   ri_entry->high, ri_entry->low);
477 	}
478 	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
479 }
480 
481 static void ir_tbl_posted_entry_show(struct seq_file *m,
482 				     struct intel_iommu *iommu)
483 {
484 	struct irte *pi_entry;
485 	unsigned long flags;
486 	int idx;
487 
488 	seq_puts(m, " Entry SrcID   PDA_high PDA_low  Vct IRTE_high\t\tIRTE_low\n");
489 
490 	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
491 	for (idx = 0; idx < INTR_REMAP_TABLE_ENTRIES; idx++) {
492 		pi_entry = &iommu->ir_table->base[idx];
493 		if (!pi_entry->present || !pi_entry->p_pst)
494 			continue;
495 
496 		seq_printf(m, " %-5d %02x:%02x.%01x %08x %08x %02x  %016llx\t%016llx\n",
497 			   idx, PCI_BUS_NUM(pi_entry->sid),
498 			   PCI_SLOT(pi_entry->sid), PCI_FUNC(pi_entry->sid),
499 			   pi_entry->pda_h, pi_entry->pda_l << 6,
500 			   pi_entry->vector, pi_entry->high,
501 			   pi_entry->low);
502 	}
503 	raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
504 }
505 
506 /*
507  * For active IOMMUs go through the Interrupt remapping
508  * table and print valid entries in a table format for
509  * Remapped and Posted Interrupts.
510  */
511 static int ir_translation_struct_show(struct seq_file *m, void *unused)
512 {
513 	struct dmar_drhd_unit *drhd;
514 	struct intel_iommu *iommu;
515 	u64 irta;
516 	u32 sts;
517 
518 	rcu_read_lock();
519 	for_each_active_iommu(iommu, drhd) {
520 		if (!ecap_ir_support(iommu->ecap))
521 			continue;
522 
523 		seq_printf(m, "Remapped Interrupt supported on IOMMU: %s\n",
524 			   iommu->name);
525 
526 		sts = dmar_readl(iommu->reg + DMAR_GSTS_REG);
527 		if (iommu->ir_table && (sts & DMA_GSTS_IRES)) {
528 			irta = virt_to_phys(iommu->ir_table->base);
529 			seq_printf(m, " IR table address:%llx\n", irta);
530 			ir_tbl_remap_entry_show(m, iommu);
531 		} else {
532 			seq_puts(m, "Interrupt Remapping is not enabled\n");
533 		}
534 		seq_putc(m, '\n');
535 	}
536 
537 	seq_puts(m, "****\n\n");
538 
539 	for_each_active_iommu(iommu, drhd) {
540 		if (!cap_pi_support(iommu->cap))
541 			continue;
542 
543 		seq_printf(m, "Posted Interrupt supported on IOMMU: %s\n",
544 			   iommu->name);
545 
546 		if (iommu->ir_table) {
547 			irta = virt_to_phys(iommu->ir_table->base);
548 			seq_printf(m, " IR table address:%llx\n", irta);
549 			ir_tbl_posted_entry_show(m, iommu);
550 		} else {
551 			seq_puts(m, "Interrupt Remapping is not enabled\n");
552 		}
553 		seq_putc(m, '\n');
554 	}
555 	rcu_read_unlock();
556 
557 	return 0;
558 }
559 DEFINE_SHOW_ATTRIBUTE(ir_translation_struct);
560 #endif
561 
562 static void latency_show_one(struct seq_file *m, struct intel_iommu *iommu,
563 			     struct dmar_drhd_unit *drhd)
564 {
565 	int ret;
566 
567 	seq_printf(m, "IOMMU: %s Register Base Address: %llx\n",
568 		   iommu->name, drhd->reg_base_addr);
569 
570 	ret = dmar_latency_snapshot(iommu, debug_buf, DEBUG_BUFFER_SIZE);
571 	if (ret < 0)
572 		seq_puts(m, "Failed to get latency snapshot");
573 	else
574 		seq_puts(m, debug_buf);
575 	seq_puts(m, "\n");
576 }
577 
578 static int latency_show(struct seq_file *m, void *v)
579 {
580 	struct dmar_drhd_unit *drhd;
581 	struct intel_iommu *iommu;
582 
583 	rcu_read_lock();
584 	for_each_active_iommu(iommu, drhd)
585 		latency_show_one(m, iommu, drhd);
586 	rcu_read_unlock();
587 
588 	return 0;
589 }
590 
591 static int dmar_perf_latency_open(struct inode *inode, struct file *filp)
592 {
593 	return single_open(filp, latency_show, NULL);
594 }
595 
596 static ssize_t dmar_perf_latency_write(struct file *filp,
597 				       const char __user *ubuf,
598 				       size_t cnt, loff_t *ppos)
599 {
600 	struct dmar_drhd_unit *drhd;
601 	struct intel_iommu *iommu;
602 	int counting;
603 	char buf[64];
604 
605 	if (cnt > 63)
606 		cnt = 63;
607 
608 	if (copy_from_user(&buf, ubuf, cnt))
609 		return -EFAULT;
610 
611 	buf[cnt] = 0;
612 
613 	if (kstrtoint(buf, 0, &counting))
614 		return -EINVAL;
615 
616 	switch (counting) {
617 	case 0:
618 		rcu_read_lock();
619 		for_each_active_iommu(iommu, drhd) {
620 			dmar_latency_disable(iommu, DMAR_LATENCY_INV_IOTLB);
621 			dmar_latency_disable(iommu, DMAR_LATENCY_INV_DEVTLB);
622 			dmar_latency_disable(iommu, DMAR_LATENCY_INV_IEC);
623 			dmar_latency_disable(iommu, DMAR_LATENCY_PRQ);
624 		}
625 		rcu_read_unlock();
626 		break;
627 	case 1:
628 		rcu_read_lock();
629 		for_each_active_iommu(iommu, drhd)
630 			dmar_latency_enable(iommu, DMAR_LATENCY_INV_IOTLB);
631 		rcu_read_unlock();
632 		break;
633 	case 2:
634 		rcu_read_lock();
635 		for_each_active_iommu(iommu, drhd)
636 			dmar_latency_enable(iommu, DMAR_LATENCY_INV_DEVTLB);
637 		rcu_read_unlock();
638 		break;
639 	case 3:
640 		rcu_read_lock();
641 		for_each_active_iommu(iommu, drhd)
642 			dmar_latency_enable(iommu, DMAR_LATENCY_INV_IEC);
643 		rcu_read_unlock();
644 		break;
645 	case 4:
646 		rcu_read_lock();
647 		for_each_active_iommu(iommu, drhd)
648 			dmar_latency_enable(iommu, DMAR_LATENCY_PRQ);
649 		rcu_read_unlock();
650 		break;
651 	default:
652 		return -EINVAL;
653 	}
654 
655 	*ppos += cnt;
656 	return cnt;
657 }
658 
659 static const struct file_operations dmar_perf_latency_fops = {
660 	.open		= dmar_perf_latency_open,
661 	.write		= dmar_perf_latency_write,
662 	.read		= seq_read,
663 	.llseek		= seq_lseek,
664 	.release	= single_release,
665 };
666 
667 void __init intel_iommu_debugfs_init(void)
668 {
669 	struct dentry *intel_iommu_debug = debugfs_create_dir("intel",
670 						iommu_debugfs_dir);
671 
672 	debugfs_create_file("iommu_regset", 0444, intel_iommu_debug, NULL,
673 			    &iommu_regset_fops);
674 	debugfs_create_file("dmar_translation_struct", 0444, intel_iommu_debug,
675 			    NULL, &dmar_translation_struct_fops);
676 	debugfs_create_file("domain_translation_struct", 0444,
677 			    intel_iommu_debug, NULL,
678 			    &domain_translation_struct_fops);
679 	debugfs_create_file("invalidation_queue", 0444, intel_iommu_debug,
680 			    NULL, &invalidation_queue_fops);
681 #ifdef CONFIG_IRQ_REMAP
682 	debugfs_create_file("ir_translation_struct", 0444, intel_iommu_debug,
683 			    NULL, &ir_translation_struct_fops);
684 #endif
685 	debugfs_create_file("dmar_perf_latency", 0644, intel_iommu_debug,
686 			    NULL, &dmar_perf_latency_fops);
687 }
688