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 /* weird loop because pt_regs regs rev r12..r0, r25..r13 */
30 for (i
= start_num
; i
< start_num
+ 13; i
++) {
31 n
+= scnprintf(buf
+ n
, len
- n
, "r%02u: 0x%08lx\t",
32 i
, (unsigned long)*reg_rev
);
34 if (((i
+ 1) % 3) == 0)
35 n
+= scnprintf(buf
+ n
, len
- n
, "\n");
41 n
+= scnprintf(buf
+ n
, len
- n
, "\n\n");
46 static void show_callee_regs(struct callee_regs
*cregs
)
48 print_reg_file(&(cregs
->r13
), 13);
51 void print_task_path_n_nm(struct task_struct
*tsk
, char *buf
)
56 struct file
*exe_file
;
58 mm
= get_task_mm(tsk
);
62 exe_file
= get_mm_exe_file(mm
);
66 path
= exe_file
->f_path
;
67 path_get(&exe_file
->f_path
);
69 path_nm
= d_path(&path
, buf
, 255);
74 pr_info("%s, TGID %u\n", path_nm
, tsk
->tgid
);
76 EXPORT_SYMBOL(print_task_path_n_nm
);
78 static void show_faulting_vma(unsigned long address
, char *buf
)
80 struct vm_area_struct
*vma
;
82 unsigned long ino
= 0;
86 vma
= find_vma(current
->active_mm
, address
);
88 /* check against the find_vma( ) behaviour which returns the next VMA
89 * if the container VMA is not found
91 if (vma
&& (vma
->vm_start
<= address
)) {
92 struct file
*file
= vma
->vm_file
;
94 struct path
*path
= &file
->f_path
;
95 nm
= d_path(path
, buf
, PAGE_SIZE
- 1);
96 inode
= vma
->vm_file
->f_path
.dentry
->d_inode
;
97 dev
= inode
->i_sb
->s_dev
;
100 pr_info(" @off 0x%lx in [%s]\n"
101 " VMA: 0x%08lx to 0x%08lx\n\n",
102 address
- vma
->vm_start
, nm
, vma
->vm_start
, vma
->vm_end
);
104 pr_info(" @No matching VMA found\n");
107 static void show_ecr_verbose(struct pt_regs
*regs
)
109 unsigned int vec
, cause_code
, cause_reg
;
110 unsigned long address
;
112 cause_reg
= current
->thread
.cause_code
;
113 pr_info("\n[ECR]: 0x%08x => ", cause_reg
);
115 /* For Data fault, this is data address not instruction addr */
116 address
= current
->thread
.fault_address
;
118 vec
= cause_reg
>> 16;
119 cause_code
= (cause_reg
>> 8) & 0xFF;
121 /* For DTLB Miss or ProtV, display the memory involved too */
122 if (vec
== ECR_V_DTLB_MISS
) {
123 pr_cont("Invalid (%s) @ 0x%08lx by insn @ 0x%08lx\n",
124 (cause_code
== 0x01) ? "Read From" :
125 ((cause_code
== 0x02) ? "Write to" : "EX"),
127 } else if (vec
== ECR_V_ITLB_MISS
) {
128 pr_cont("Insn could not be fetched\n");
129 } else if (vec
== ECR_V_MACH_CHK
) {
130 pr_cont("%s\n", (cause_code
== 0x0) ?
131 "Double Fault" : "Other Fatal Err");
133 } else if (vec
== ECR_V_PROTV
) {
134 if (cause_code
== ECR_C_PROTV_INST_FETCH
)
135 pr_cont("Execute from Non-exec Page\n");
136 else if (cause_code
== ECR_C_PROTV_LOAD
)
137 pr_cont("Read from Non-readable Page\n");
138 else if (cause_code
== ECR_C_PROTV_STORE
)
139 pr_cont("Write to Non-writable Page\n");
140 else if (cause_code
== ECR_C_PROTV_XCHG
)
141 pr_cont("Data exchange protection violation\n");
142 else if (cause_code
== ECR_C_PROTV_MISALIG_DATA
)
143 pr_cont("Misaligned r/w from 0x%08lx\n", address
);
144 } else if (vec
== ECR_V_INSN_ERR
) {
145 pr_cont("Illegal Insn\n");
147 pr_cont("Check Programmer's Manual\n");
151 /************************************************************************
152 * API called by rest of kernel
153 ***********************************************************************/
155 void show_regs(struct pt_regs
*regs
)
157 struct task_struct
*tsk
= current
;
158 struct callee_regs
*cregs
;
161 buf
= (char *)__get_free_page(GFP_TEMPORARY
);
165 print_task_path_n_nm(tsk
, buf
);
167 if (current
->thread
.cause_code
)
168 show_ecr_verbose(regs
);
170 pr_info("[EFA]: 0x%08lx\n", current
->thread
.fault_address
);
171 pr_info("[ERET]: 0x%08lx (PC of Faulting Instr)\n", regs
->ret
);
173 show_faulting_vma(regs
->ret
, buf
); /* faulting code, not data */
175 /* can't use print_vma_addr() yet as it doesn't check for
179 /* print special regs */
180 pr_info("status32: 0x%08lx\n", regs
->status32
);
181 pr_info(" SP: 0x%08lx\tFP: 0x%08lx\n", regs
->sp
, regs
->fp
);
182 pr_info("BTA: 0x%08lx\tBLINK: 0x%08lx\n",
183 regs
->bta
, regs
->blink
);
184 pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
185 regs
->lp_start
, regs
->lp_end
, regs
->lp_count
);
187 /* print regs->r0 thru regs->r12
188 * Sequential printing was generating horrible code
190 print_reg_file(&(regs
->r0
), 0);
192 /* If Callee regs were saved, display them too */
193 cregs
= (struct callee_regs
*)current
->thread
.callee_reg
;
195 show_callee_regs(cregs
);
197 free_page((unsigned long)buf
);
200 void show_kernel_fault_diag(const char *str
, struct pt_regs
*regs
,
201 unsigned long address
, unsigned long cause_reg
)
203 current
->thread
.fault_address
= address
;
204 current
->thread
.cause_code
= cause_reg
;
206 /* Caller and Callee regs */
209 /* Show stack trace if this Fatality happened in kernel mode */
210 if (!user_mode(regs
))
211 show_stacktrace(current
, regs
);
214 #ifdef CONFIG_DEBUG_FS
216 #include <linux/module.h>
217 #include <linux/fs.h>
218 #include <linux/mount.h>
219 #include <linux/pagemap.h>
220 #include <linux/init.h>
221 #include <linux/namei.h>
222 #include <linux/debugfs.h>
224 static struct dentry
*test_dentry
;
225 static struct dentry
*test_dir
;
226 static struct dentry
*test_u32_dentry
;
228 static u32 clr_on_read
= 1;
230 #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
231 u32 numitlb
, numdtlb
, num_pte_not_present
;
233 static int fill_display_data(char *kbuf
)
236 num
+= sprintf(kbuf
+ num
, "I-TLB Miss %x\n", numitlb
);
237 num
+= sprintf(kbuf
+ num
, "D-TLB Miss %x\n", numdtlb
);
238 num
+= sprintf(kbuf
+ num
, "PTE not present %x\n", num_pte_not_present
);
241 numitlb
= numdtlb
= num_pte_not_present
= 0;
246 static int tlb_stats_open(struct inode
*inode
, struct file
*file
)
248 file
->private_data
= (void *)__get_free_page(GFP_KERNEL
);
252 /* called on user read(): display the couters */
253 static ssize_t
tlb_stats_output(struct file
*file
, /* file descriptor */
254 char __user
*user_buf
, /* user buffer */
255 size_t len
, /* length of buffer */
256 loff_t
*offset
) /* offset in the file */
259 char *kbuf
= (char *)file
->private_data
;
261 /* All of the data can he shoved in one iteration */
265 num
= fill_display_data(kbuf
);
267 /* simple_read_from_buffer() is helper for copy to user space
268 It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
269 @3 (offset) into the user space address starting at @1 (user_buf).
270 @5 (len) is max size of user buffer
272 return simple_read_from_buffer(user_buf
, num
, offset
, kbuf
, len
);
275 /* called on user write : clears the counters */
276 static ssize_t
tlb_stats_clear(struct file
*file
, const char __user
*user_buf
,
277 size_t length
, loff_t
*offset
)
279 numitlb
= numdtlb
= num_pte_not_present
= 0;
283 static int tlb_stats_close(struct inode
*inode
, struct file
*file
)
285 free_page((unsigned long)(file
->private_data
));
289 static const struct file_operations tlb_stats_file_ops
= {
290 .read
= tlb_stats_output
,
291 .write
= tlb_stats_clear
,
292 .open
= tlb_stats_open
,
293 .release
= tlb_stats_close
297 static int __init
arc_debugfs_init(void)
299 test_dir
= debugfs_create_dir("arc", NULL
);
301 #ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
302 test_dentry
= debugfs_create_file("tlb_stats", 0444, test_dir
, NULL
,
303 &tlb_stats_file_ops
);
307 debugfs_create_u32("clr_on_read", 0444, test_dir
, &clr_on_read
);
312 module_init(arc_debugfs_init
);
314 static void __exit
arc_debugfs_exit(void)
316 debugfs_remove(test_u32_dentry
);
317 debugfs_remove(test_dentry
);
318 debugfs_remove(test_dir
);
320 module_exit(arc_debugfs_exit
);