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, ®s_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 } 275