1/*
2 * arch/sh/mm/tlb-debugfs.c
3 *
4 * debugfs ops for SH-4 ITLB/UTLBs.
5 *
6 * Copyright (C) 2010  Matt Fleming
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License.  See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/debugfs.h>
15#include <linux/seq_file.h>
16#include <asm/processor.h>
17#include <asm/mmu_context.h>
18#include <asm/tlbflush.h>
19
20enum tlb_type {
21	TLB_TYPE_ITLB,
22	TLB_TYPE_UTLB,
23};
24
25static struct {
26	int bits;
27	const char *size;
28} tlb_sizes[] = {
29	{ 0x0, "  1KB" },
30	{ 0x1, "  4KB" },
31	{ 0x2, "  8KB" },
32	{ 0x4, " 64KB" },
33	{ 0x5, "256KB" },
34	{ 0x7, "  1MB" },
35	{ 0x8, "  4MB" },
36	{ 0xc, " 64MB" },
37};
38
39static int tlb_seq_show(struct seq_file *file, void *iter)
40{
41	unsigned int tlb_type = (unsigned int)file->private;
42	unsigned long addr1, addr2, data1, data2;
43	unsigned long flags;
44	unsigned long mmucr;
45	unsigned int nentries, entry;
46	unsigned int urb;
47
48	mmucr = __raw_readl(MMUCR);
49	if ((mmucr & 0x1) == 0) {
50		seq_printf(file, "address translation disabled\n");
51		return 0;
52	}
53
54	if (tlb_type == TLB_TYPE_ITLB) {
55		addr1 = MMU_ITLB_ADDRESS_ARRAY;
56		addr2 = MMU_ITLB_ADDRESS_ARRAY2;
57		data1 = MMU_ITLB_DATA_ARRAY;
58		data2 = MMU_ITLB_DATA_ARRAY2;
59		nentries = 4;
60	} else {
61		addr1 = MMU_UTLB_ADDRESS_ARRAY;
62		addr2 = MMU_UTLB_ADDRESS_ARRAY2;
63		data1 = MMU_UTLB_DATA_ARRAY;
64		data2 = MMU_UTLB_DATA_ARRAY2;
65		nentries = 64;
66	}
67
68	local_irq_save(flags);
69	jump_to_uncached();
70
71	urb = (mmucr & MMUCR_URB) >> MMUCR_URB_SHIFT;
72
73	/* Make the "entry >= urb" test fail. */
74	if (urb == 0)
75		urb = MMUCR_URB_NENTRIES + 1;
76
77	if (tlb_type == TLB_TYPE_ITLB) {
78		addr1 = MMU_ITLB_ADDRESS_ARRAY;
79		addr2 = MMU_ITLB_ADDRESS_ARRAY2;
80		data1 = MMU_ITLB_DATA_ARRAY;
81		data2 = MMU_ITLB_DATA_ARRAY2;
82		nentries = 4;
83	} else {
84		addr1 = MMU_UTLB_ADDRESS_ARRAY;
85		addr2 = MMU_UTLB_ADDRESS_ARRAY2;
86		data1 = MMU_UTLB_DATA_ARRAY;
87		data2 = MMU_UTLB_DATA_ARRAY2;
88		nentries = 64;
89	}
90
91	seq_printf(file, "entry:     vpn        ppn     asid  size valid wired\n");
92
93	for (entry = 0; entry < nentries; entry++) {
94		unsigned long vpn, ppn, asid, size;
95		unsigned long valid;
96		unsigned long val;
97		const char *sz = "    ?";
98		int i;
99
100		val = __raw_readl(addr1 | (entry << MMU_TLB_ENTRY_SHIFT));
101		ctrl_barrier();
102		vpn = val & 0xfffffc00;
103		valid = val & 0x100;
104
105		val = __raw_readl(addr2 | (entry << MMU_TLB_ENTRY_SHIFT));
106		ctrl_barrier();
107		asid = val & MMU_CONTEXT_ASID_MASK;
108
109		val = __raw_readl(data1 | (entry << MMU_TLB_ENTRY_SHIFT));
110		ctrl_barrier();
111		ppn = (val & 0x0ffffc00) << 4;
112
113		val = __raw_readl(data2 | (entry << MMU_TLB_ENTRY_SHIFT));
114		ctrl_barrier();
115		size = (val & 0xf0) >> 4;
116
117		for (i = 0; i < ARRAY_SIZE(tlb_sizes); i++) {
118			if (tlb_sizes[i].bits == size)
119				break;
120		}
121
122		if (i != ARRAY_SIZE(tlb_sizes))
123			sz = tlb_sizes[i].size;
124
125		seq_printf(file, "%2d:    0x%08lx 0x%08lx %5lu %s   %s     %s\n",
126			   entry, vpn, ppn, asid,
127			   sz, valid ? "V" : "-",
128			   (urb <= entry) ? "W" : "-");
129	}
130
131	back_to_cached();
132	local_irq_restore(flags);
133
134	return 0;
135}
136
137static int tlb_debugfs_open(struct inode *inode, struct file *file)
138{
139	return single_open(file, tlb_seq_show, inode->i_private);
140}
141
142static const struct file_operations tlb_debugfs_fops = {
143	.owner		= THIS_MODULE,
144	.open		= tlb_debugfs_open,
145	.read		= seq_read,
146	.llseek		= seq_lseek,
147	.release	= single_release,
148};
149
150static int __init tlb_debugfs_init(void)
151{
152	struct dentry *itlb, *utlb;
153
154	itlb = debugfs_create_file("itlb", S_IRUSR, arch_debugfs_dir,
155				   (unsigned int *)TLB_TYPE_ITLB,
156				   &tlb_debugfs_fops);
157	if (unlikely(!itlb))
158		return -ENOMEM;
159
160	utlb = debugfs_create_file("utlb", S_IRUSR, arch_debugfs_dir,
161				   (unsigned int *)TLB_TYPE_UTLB,
162				   &tlb_debugfs_fops);
163	if (unlikely(!utlb)) {
164		debugfs_remove(itlb);
165		return -ENOMEM;
166	}
167
168	return 0;
169}
170module_init(tlb_debugfs_init);
171
172MODULE_LICENSE("GPL v2");
173