2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
8 #include <linux/ptrace.h>
9 #include <linux/module.h>
12 #include <linux/kdev_t.h>
13 #include <linux/fs_struct.h>
14 #include <linux/proc_fs.h>
15 #include <linux/file.h>
16 #include <asm/arcregs.h>
19 * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25)
20 * -Prints 3 regs per line and a CR.
21 * -To continue, callee regs right after scratch, special handling of CR
23 static noinline void print_reg_file(long *reg_rev, int start_num)
27 int n = 0, len = sizeof(buf);
29 for (i = start_num; i < start_num + 13; i++) {
30 n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t",
31 i, (unsigned long)*reg_rev);
33 if (((i + 1) % 3) == 0)
34 n += scnprintf(buf + n, len - n, "\n");
36 /* because pt_regs has regs reversed: r12..r0, r25..r13 */
41 n += scnprintf(buf + n, len - n, "\n\n");
43 /* To continue printing callee regs on same line as scratch regs */
50 static void show_callee_regs(struct callee_regs *cregs)
52 print_reg_file(&(cregs->r13), 13);
55 static void print_task_path_n_nm(struct task_struct *tsk, char *buf)
60 struct file *exe_file;
62 mm = get_task_mm(tsk);
66 exe_file = get_mm_exe_file(mm);
70 path_nm = file_path(exe_file, buf, 255);
75 pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?");
78 static void show_faulting_vma(unsigned long address, char *buf)
80 struct vm_area_struct *vma;
82 unsigned long ino = 0;
85 struct mm_struct *active_mm = current->active_mm;
87 /* can't use print_vma_addr() yet as it doesn't check for
90 down_read(&active_mm->mmap_sem);
91 vma = find_vma(active_mm, address);
93 /* check against the find_vma( ) behaviour which returns the next VMA
94 * if the container VMA is not found
96 if (vma && (vma->vm_start <= address)) {
97 struct file *file = vma->vm_file;
99 nm = file_path(file, buf, PAGE_SIZE - 1);
100 inode = file_inode(vma->vm_file);
101 dev = inode->i_sb->s_dev;
104 pr_info(" @off 0x%lx in [%s]\n"
105 " VMA: 0x%08lx to 0x%08lx\n",
106 vma->vm_start < TASK_UNMAPPED_BASE ?
107 address : address - vma->vm_start,
108 nm, vma->vm_start, vma->vm_end);
110 pr_info(" @No matching VMA found\n");
112 up_read(&active_mm->mmap_sem);
115 static void show_ecr_verbose(struct pt_regs *regs)
117 unsigned int vec, cause_code;
118 unsigned long address;
120 pr_info("\n[ECR ]: 0x%08lx => ", regs->event);
122 /* For Data fault, this is data address not instruction addr */
123 address = current->thread.fault_address;
126 cause_code = regs->ecr_cause;
128 /* For DTLB Miss or ProtV, display the memory involved too */
129 if (vec == ECR_V_DTLB_MISS) {
130 pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n",
131 (cause_code == 0x01) ? "Read" :
132 ((cause_code == 0x02) ? "Write" : "EX"),
134 } else if (vec == ECR_V_ITLB_MISS) {
135 pr_cont("Insn could not be fetched\n");
136 } else if (vec == ECR_V_MACH_CHK) {
137 pr_cont("%s\n", (cause_code == 0x0) ?
138 "Double Fault" : "Other Fatal Err");
140 } else if (vec == ECR_V_PROTV) {
141 if (cause_code == ECR_C_PROTV_INST_FETCH)
142 pr_cont("Execute from Non-exec Page\n");
143 else if (cause_code == ECR_C_PROTV_MISALIG_DATA)
144 pr_cont("Misaligned r/w from 0x%08lx\n", address);
146 pr_cont("%s access not allowed on page\n",
147 (cause_code == 0x01) ? "Read" :
148 ((cause_code == 0x02) ? "Write" : "EX"));
149 } else if (vec == ECR_V_INSN_ERR) {
150 pr_cont("Illegal Insn\n");
152 pr_cont("Check Programmer's Manual\n");
156 /************************************************************************
157 * API called by rest of kernel
158 ***********************************************************************/
160 void show_regs(struct pt_regs *regs)
162 struct task_struct *tsk = current;
163 struct callee_regs *cregs;
166 buf = (char *)__get_free_page(GFP_TEMPORARY);
170 print_task_path_n_nm(tsk, buf);
171 show_regs_print_info(KERN_INFO);
173 show_ecr_verbose(regs);
175 pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n",
176 current->thread.fault_address,
177 (void *)regs->blink, (void *)regs->ret);
180 show_faulting_vma(regs->ret, buf); /* faulting code, not data */
182 pr_info("[STAT32]: 0x%08lx", regs->status32);
184 #define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit : ""
185 if (!user_mode(regs))
186 pr_cont(" : %2s %2s %2s %2s %2s\n",
187 STS_BIT(regs, AE), STS_BIT(regs, A2), STS_BIT(regs, A1),
188 STS_BIT(regs, E2), STS_BIT(regs, E1));
190 pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n",
191 regs->bta, regs->sp, regs->fp);
192 pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
193 regs->lp_start, regs->lp_end, regs->lp_count);
195 /* print regs->r0 thru regs->r12
196 * Sequential printing was generating horrible code
198 print_reg_file(&(regs->r0), 0);
200 /* If Callee regs were saved, display them too */
201 cregs = (struct callee_regs *)current->thread.callee_reg;
203 show_callee_regs(cregs);
205 free_page((unsigned long)buf);
208 void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
209 unsigned long address)
211 current->thread.fault_address = address;
213 /* Caller and Callee regs */
216 /* Show stack trace if this Fatality happened in kernel mode */
217 if (!user_mode(regs))
218 show_stacktrace(current, regs);
221 #ifdef CONFIG_DEBUG_FS
223 #include <linux/module.h>
224 #include <linux/fs.h>
225 #include <linux/mount.h>
226 #include <linux/pagemap.h>
227 #include <linux/init.h>
228 #include <linux/namei.h>
229 #include <linux/debugfs.h>
231 static struct dentry *test_dentry;
232 static struct dentry *test_dir;
233 static struct dentry *test_u32_dentry;
235 static u32 clr_on_read = 1;
237 #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
238 u32 numitlb, numdtlb, num_pte_not_present;
240 static int fill_display_data(char *kbuf)
243 num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
244 num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
245 num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);
248 numitlb = numdtlb = num_pte_not_present = 0;
253 static int tlb_stats_open(struct inode *inode, struct file *file)
255 file->private_data = (void *)__get_free_page(GFP_KERNEL);
259 /* called on user read(): display the couters */
260 static ssize_t tlb_stats_output(struct file *file, /* file descriptor */
261 char __user *user_buf, /* user buffer */
262 size_t len, /* length of buffer */
263 loff_t *offset) /* offset in the file */
266 char *kbuf = (char *)file->private_data;
268 /* All of the data can he shoved in one iteration */
272 num = fill_display_data(kbuf);
274 /* simple_read_from_buffer() is helper for copy to user space
275 It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
276 @3 (offset) into the user space address starting at @1 (user_buf).
277 @5 (len) is max size of user buffer
279 return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
282 /* called on user write : clears the counters */
283 static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf,
284 size_t length, loff_t *offset)
286 numitlb = numdtlb = num_pte_not_present = 0;
290 static int tlb_stats_close(struct inode *inode, struct file *file)
292 free_page((unsigned long)(file->private_data));
296 static const struct file_operations tlb_stats_file_ops = {
297 .read = tlb_stats_output,
298 .write = tlb_stats_clear,
299 .open = tlb_stats_open,
300 .release = tlb_stats_close
304 static int __init arc_debugfs_init(void)
306 test_dir = debugfs_create_dir("arc", NULL);
308 #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
309 test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
310 &tlb_stats_file_ops);
314 debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);
319 module_init(arc_debugfs_init);
321 static void __exit arc_debugfs_exit(void)
323 debugfs_remove(test_u32_dentry);
324 debugfs_remove(test_dentry);
325 debugfs_remove(test_dir);
327 module_exit(arc_debugfs_exit);