GNU Linux-libre 5.10.219-gnu1
[releases.git] / drivers / iommu / omap-iommu-debug.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * omap iommu: debugfs interface
4  *
5  * Copyright (C) 2008-2009 Nokia Corporation
6  *
7  * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
8  */
9
10 #include <linux/err.h>
11 #include <linux/io.h>
12 #include <linux/slab.h>
13 #include <linux/uaccess.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/debugfs.h>
16 #include <linux/platform_data/iommu-omap.h>
17
18 #include "omap-iopgtable.h"
19 #include "omap-iommu.h"
20
21 static DEFINE_MUTEX(iommu_debug_lock);
22
23 static struct dentry *iommu_debug_root;
24
25 static inline bool is_omap_iommu_detached(struct omap_iommu *obj)
26 {
27         return !obj->domain;
28 }
29
30 #define pr_reg(name)                                                    \
31         do {                                                            \
32                 ssize_t bytes;                                          \
33                 const char *str = "%20s: %08x\n";                       \
34                 const int maxcol = 32;                                  \
35                 if (len < maxcol)                                       \
36                         goto out;                                       \
37                 bytes = scnprintf(p, maxcol, str, __stringify(name),    \
38                                  iommu_read_reg(obj, MMU_##name));      \
39                 p += bytes;                                             \
40                 len -= bytes;                                           \
41         } while (0)
42
43 static ssize_t
44 omap2_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t len)
45 {
46         char *p = buf;
47
48         pr_reg(REVISION);
49         pr_reg(IRQSTATUS);
50         pr_reg(IRQENABLE);
51         pr_reg(WALKING_ST);
52         pr_reg(CNTL);
53         pr_reg(FAULT_AD);
54         pr_reg(TTB);
55         pr_reg(LOCK);
56         pr_reg(LD_TLB);
57         pr_reg(CAM);
58         pr_reg(RAM);
59         pr_reg(GFLUSH);
60         pr_reg(FLUSH_ENTRY);
61         pr_reg(READ_CAM);
62         pr_reg(READ_RAM);
63         pr_reg(EMU_FAULT_AD);
64 out:
65         return p - buf;
66 }
67
68 static ssize_t omap_iommu_dump_ctx(struct omap_iommu *obj, char *buf,
69                                    ssize_t bytes)
70 {
71         if (!obj || !buf)
72                 return -EINVAL;
73
74         pm_runtime_get_sync(obj->dev);
75
76         bytes = omap2_iommu_dump_ctx(obj, buf, bytes);
77
78         pm_runtime_put_sync(obj->dev);
79
80         return bytes;
81 }
82
83 static ssize_t debug_read_regs(struct file *file, char __user *userbuf,
84                                size_t count, loff_t *ppos)
85 {
86         struct omap_iommu *obj = file->private_data;
87         char *p, *buf;
88         ssize_t bytes;
89
90         if (is_omap_iommu_detached(obj))
91                 return -EPERM;
92
93         buf = kmalloc(count, GFP_KERNEL);
94         if (!buf)
95                 return -ENOMEM;
96         p = buf;
97
98         mutex_lock(&iommu_debug_lock);
99
100         bytes = omap_iommu_dump_ctx(obj, p, count);
101         if (bytes < 0)
102                 goto err;
103         bytes = simple_read_from_buffer(userbuf, count, ppos, buf, bytes);
104
105 err:
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         seq_printf(s, "%08x %08x %01x\n", cr->cam, cr->ram,
139                    (cr->cam & MMU_CAM_P) ? 1 : 0);
140         return 0;
141 }
142
143 static size_t omap_dump_tlb_entries(struct omap_iommu *obj, struct seq_file *s)
144 {
145         int i, num;
146         struct cr_regs *cr;
147
148         num = obj->nr_tlb_entries;
149
150         cr = kcalloc(num, sizeof(*cr), GFP_KERNEL);
151         if (!cr)
152                 return 0;
153
154         num = __dump_tlb_entries(obj, cr, num);
155         for (i = 0; i < num; i++)
156                 iotlb_dump_cr(obj, cr + i, s);
157         kfree(cr);
158
159         return 0;
160 }
161
162 static int tlb_show(struct seq_file *s, void *data)
163 {
164         struct omap_iommu *obj = s->private;
165
166         if (is_omap_iommu_detached(obj))
167                 return -EPERM;
168
169         mutex_lock(&iommu_debug_lock);
170
171         seq_printf(s, "%8s %8s\n", "cam:", "ram:");
172         seq_puts(s, "-----------------------------------------\n");
173         omap_dump_tlb_entries(obj, s);
174
175         mutex_unlock(&iommu_debug_lock);
176
177         return 0;
178 }
179
180 static void dump_ioptable(struct seq_file *s)
181 {
182         int i, j;
183         u32 da;
184         u32 *iopgd, *iopte;
185         struct omap_iommu *obj = s->private;
186
187         spin_lock(&obj->page_table_lock);
188
189         iopgd = iopgd_offset(obj, 0);
190         for (i = 0; i < PTRS_PER_IOPGD; i++, iopgd++) {
191                 if (!*iopgd)
192                         continue;
193
194                 if (!(*iopgd & IOPGD_TABLE)) {
195                         da = i << IOPGD_SHIFT;
196                         seq_printf(s, "1: 0x%08x 0x%08x\n", da, *iopgd);
197                         continue;
198                 }
199
200                 iopte = iopte_offset(iopgd, 0);
201                 for (j = 0; j < PTRS_PER_IOPTE; j++, iopte++) {
202                         if (!*iopte)
203                                 continue;
204
205                         da = (i << IOPGD_SHIFT) + (j << IOPTE_SHIFT);
206                         seq_printf(s, "2: 0x%08x 0x%08x\n", da, *iopte);
207                 }
208         }
209
210         spin_unlock(&obj->page_table_lock);
211 }
212
213 static int pagetable_show(struct seq_file *s, void *data)
214 {
215         struct omap_iommu *obj = s->private;
216
217         if (is_omap_iommu_detached(obj))
218                 return -EPERM;
219
220         mutex_lock(&iommu_debug_lock);
221
222         seq_printf(s, "L: %8s %8s\n", "da:", "pte:");
223         seq_puts(s, "--------------------------\n");
224         dump_ioptable(s);
225
226         mutex_unlock(&iommu_debug_lock);
227
228         return 0;
229 }
230
231 #define DEBUG_FOPS_RO(name)                                             \
232         static const struct file_operations name##_fops = {             \
233                 .open = simple_open,                                    \
234                 .read = debug_read_##name,                              \
235                 .llseek = generic_file_llseek,                          \
236         }
237
238 DEBUG_FOPS_RO(regs);
239 DEFINE_SHOW_ATTRIBUTE(tlb);
240 DEFINE_SHOW_ATTRIBUTE(pagetable);
241
242 void omap_iommu_debugfs_add(struct omap_iommu *obj)
243 {
244         struct dentry *d;
245
246         if (!iommu_debug_root)
247                 return;
248
249         d = debugfs_create_dir(obj->name, iommu_debug_root);
250         obj->debug_dir = d;
251
252         debugfs_create_u32("nr_tlb_entries", 0400, d, &obj->nr_tlb_entries);
253         debugfs_create_file("regs", 0400, d, obj, &regs_fops);
254         debugfs_create_file("tlb", 0400, d, obj, &tlb_fops);
255         debugfs_create_file("pagetable", 0400, d, obj, &pagetable_fops);
256 }
257
258 void omap_iommu_debugfs_remove(struct omap_iommu *obj)
259 {
260         if (!obj->debug_dir)
261                 return;
262
263         debugfs_remove_recursive(obj->debug_dir);
264 }
265
266 void __init omap_iommu_debugfs_init(void)
267 {
268         iommu_debug_root = debugfs_create_dir("omap_iommu", NULL);
269 }
270
271 void __exit omap_iommu_debugfs_exit(void)
272 {
273         debugfs_remove(iommu_debug_root);
274 }