xref: /linux/drivers/iommu/omap-iommu-debug.c (revision 91e60eb60bdf078fc58b8d2fd1ac12f3c09bb893)
1 /*
2  * omap iommu: debugfs interface
3  *
4  * Copyright (C) 2008-2009 Nokia Corporation
5  *
6  * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/err.h>
14 #include <linux/io.h>
15 #include <linux/slab.h>
16 #include <linux/uaccess.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/debugfs.h>
19 #include <linux/platform_data/iommu-omap.h>
20 
21 #include "omap-iopgtable.h"
22 #include "omap-iommu.h"
23 
24 static DEFINE_MUTEX(iommu_debug_lock);
25 
26 static struct dentry *iommu_debug_root;
27 
28 static inline bool is_omap_iommu_detached(struct omap_iommu *obj)
29 {
30 	return !obj->domain;
31 }
32 
33 #define pr_reg(name)							\
34 	do {								\
35 		ssize_t bytes;						\
36 		const char *str = "%20s: %08x\n";			\
37 		const int maxcol = 32;					\
38 		bytes = snprintf(p, maxcol, str, __stringify(name),	\
39 				 iommu_read_reg(obj, MMU_##name));	\
40 		p += bytes;						\
41 		len -= bytes;						\
42 		if (len < maxcol)					\
43 			goto out;					\
44 	} while (0)
45 
46 static ssize_t
47 omap2_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t len)
48 {
49 	char *p = buf;
50 
51 	pr_reg(REVISION);
52 	pr_reg(IRQSTATUS);
53 	pr_reg(IRQENABLE);
54 	pr_reg(WALKING_ST);
55 	pr_reg(CNTL);
56 	pr_reg(FAULT_AD);
57 	pr_reg(TTB);
58 	pr_reg(LOCK);
59 	pr_reg(LD_TLB);
60 	pr_reg(CAM);
61 	pr_reg(RAM);
62 	pr_reg(GFLUSH);
63 	pr_reg(FLUSH_ENTRY);
64 	pr_reg(READ_CAM);
65 	pr_reg(READ_RAM);
66 	pr_reg(EMU_FAULT_AD);
67 out:
68 	return p - buf;
69 }
70 
71 static ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf,
72 				   ssize_t bytes)
73 {
74 	if (!obj || !buf)
75 		return -EINVAL;
76 
77 	pm_runtime_get_sync(obj->dev);
78 
79 	bytes = omap2_iommu_dump_ctx(obj, buf, bytes);
80 
81 	pm_runtime_put_sync(obj->dev);
82 
83 	return bytes;
84 }
85 
86 static ssize_t debug_read_regs(struct file *file, char __user *userbuf,
87 			       size_t count, loff_t *ppos)
88 {
89 	struct omap_iommu *obj = file->private_data;
90 	char *p, *buf;
91 	ssize_t bytes;
92 
93 	if (is_omap_iommu_detached(obj))
94 		return -EPERM;
95 
96 	buf = kmalloc(count, GFP_KERNEL);
97 	if (!buf)
98 		return -ENOMEM;
99 	p = buf;
100 
101 	mutex_lock(&iommu_debug_lock);
102 
103 	bytes = omap_iommu_dump_ctx(obj, p, count);
104 	bytes = simple_read_from_buffer(userbuf, count, ppos, buf, bytes);
105 
106 	mutex_unlock(&iommu_debug_lock);
107 	kfree(buf);
108 
109 	return bytes;
110 }
111 
112 static int
113 __dump_tlb_entries(struct omap_iommu *obj, struct cr_regs *crs, int num)
114 {
115 	int i;
116 	struct iotlb_lock saved;
117 	struct cr_regs tmp;
118 	struct cr_regs *p = crs;
119 
120 	pm_runtime_get_sync(obj->dev);
121 	iotlb_lock_get(obj, &saved);
122 
123 	for_each_iotlb_cr(obj, num, i, tmp) {
124 		if (!iotlb_cr_valid(&tmp))
125 			continue;
126 		*p++ = tmp;
127 	}
128 
129 	iotlb_lock_set(obj, &saved);
130 	pm_runtime_put_sync(obj->dev);
131 
132 	return  p - crs;
133 }
134 
135 static ssize_t iotlb_dump_cr(struct omap_iommu *obj, struct cr_regs *cr,
136 			     struct seq_file *s)
137 {
138 	return seq_printf(s, "%08x %08x %01x\n", cr->cam, cr->ram,
139 			  (cr->cam & MMU_CAM_P) ? 1 : 0);
140 }
141 
142 static size_t omap_dump_tlb_entries(struct omap_iommu *obj, struct seq_file *s)
143 {
144 	int i, num;
145 	struct cr_regs *cr;
146 
147 	num = obj->nr_tlb_entries;
148 
149 	cr = kcalloc(num, sizeof(*cr), GFP_KERNEL);
150 	if (!cr)
151 		return 0;
152 
153 	num = __dump_tlb_entries(obj, cr, num);
154 	for (i = 0; i < num; i++)
155 		iotlb_dump_cr(obj, cr + i, s);
156 	kfree(cr);
157 
158 	return 0;
159 }
160 
161 static int debug_read_tlb(struct seq_file *s, void *data)
162 {
163 	struct omap_iommu *obj = s->private;
164 
165 	if (is_omap_iommu_detached(obj))
166 		return -EPERM;
167 
168 	mutex_lock(&iommu_debug_lock);
169 
170 	seq_printf(s, "%8s %8s\n", "cam:", "ram:");
171 	seq_puts(s, "-----------------------------------------\n");
172 	omap_dump_tlb_entries(obj, s);
173 
174 	mutex_unlock(&iommu_debug_lock);
175 
176 	return 0;
177 }
178 
179 static void dump_ioptable(struct seq_file *s)
180 {
181 	int i, j;
182 	u32 da;
183 	u32 *iopgd, *iopte;
184 	struct omap_iommu *obj = s->private;
185 
186 	spin_lock(&obj->page_table_lock);
187 
188 	iopgd = iopgd_offset(obj, 0);
189 	for (i = 0; i < PTRS_PER_IOPGD; i++, iopgd++) {
190 		if (!*iopgd)
191 			continue;
192 
193 		if (!(*iopgd & IOPGD_TABLE)) {
194 			da = i << IOPGD_SHIFT;
195 			seq_printf(s, "1: 0x%08x 0x%08x\n", da, *iopgd);
196 			continue;
197 		}
198 
199 		iopte = iopte_offset(iopgd, 0);
200 		for (j = 0; j < PTRS_PER_IOPTE; j++, iopte++) {
201 			if (!*iopte)
202 				continue;
203 
204 			da = (i << IOPGD_SHIFT) + (j << IOPTE_SHIFT);
205 			seq_printf(s, "2: 0x%08x 0x%08x\n", da, *iopte);
206 		}
207 	}
208 
209 	spin_unlock(&obj->page_table_lock);
210 }
211 
212 static int debug_read_pagetable(struct seq_file *s, void *data)
213 {
214 	struct omap_iommu *obj = s->private;
215 
216 	if (is_omap_iommu_detached(obj))
217 		return -EPERM;
218 
219 	mutex_lock(&iommu_debug_lock);
220 
221 	seq_printf(s, "L: %8s %8s\n", "da:", "pte:");
222 	seq_puts(s, "--------------------------\n");
223 	dump_ioptable(s);
224 
225 	mutex_unlock(&iommu_debug_lock);
226 
227 	return 0;
228 }
229 
230 #define DEBUG_SEQ_FOPS_RO(name)						       \
231 	static int debug_open_##name(struct inode *inode, struct file *file)   \
232 	{								       \
233 		return single_open(file, debug_read_##name, inode->i_private); \
234 	}								       \
235 									       \
236 	static const struct file_operations debug_##name##_fops = {	       \
237 		.open		= debug_open_##name,			       \
238 		.read		= seq_read,				       \
239 		.llseek		= seq_lseek,				       \
240 		.release	= single_release,			       \
241 	}
242 
243 #define DEBUG_FOPS_RO(name)						\
244 	static const struct file_operations debug_##name##_fops = {	\
245 		.open = simple_open,					\
246 		.read = debug_read_##name,				\
247 		.llseek = generic_file_llseek,				\
248 	}
249 
250 DEBUG_FOPS_RO(regs);
251 DEBUG_SEQ_FOPS_RO(tlb);
252 DEBUG_SEQ_FOPS_RO(pagetable);
253 
254 #define __DEBUG_ADD_FILE(attr, mode)					\
255 	{								\
256 		struct dentry *dent;					\
257 		dent = debugfs_create_file(#attr, mode, obj->debug_dir,	\
258 					   obj, &debug_##attr##_fops);	\
259 		if (!dent)						\
260 			goto err;					\
261 	}
262 
263 #define DEBUG_ADD_FILE_RO(name) __DEBUG_ADD_FILE(name, 0400)
264 
265 void omap_iommu_debugfs_add(struct omap_iommu *obj)
266 {
267 	struct dentry *d;
268 
269 	if (!iommu_debug_root)
270 		return;
271 
272 	obj->debug_dir = debugfs_create_dir(obj->name, iommu_debug_root);
273 	if (!obj->debug_dir)
274 		return;
275 
276 	d = debugfs_create_u8("nr_tlb_entries", 0400, obj->debug_dir,
277 			      (u8 *)&obj->nr_tlb_entries);
278 	if (!d)
279 		return;
280 
281 	DEBUG_ADD_FILE_RO(regs);
282 	DEBUG_ADD_FILE_RO(tlb);
283 	DEBUG_ADD_FILE_RO(pagetable);
284 
285 	return;
286 
287 err:
288 	debugfs_remove_recursive(obj->debug_dir);
289 }
290 
291 void omap_iommu_debugfs_remove(struct omap_iommu *obj)
292 {
293 	if (!obj->debug_dir)
294 		return;
295 
296 	debugfs_remove_recursive(obj->debug_dir);
297 }
298 
299 void __init omap_iommu_debugfs_init(void)
300 {
301 	iommu_debug_root = debugfs_create_dir("omap_iommu", NULL);
302 	if (!iommu_debug_root)
303 		pr_err("can't create debugfs dir\n");
304 }
305 
306 void __exit omap_iommu_debugfs_exit(void)
307 {
308 	debugfs_remove(iommu_debug_root);
309 }
310