xref: /linux/arch/mips/lib/dump_tlb.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * Dump R4x00 TLB for debugging purposes.
3  *
4  * Copyright (C) 1994, 1995 by Waldorf Electronics, written by Ralf Baechle.
5  * Copyright (C) 1999 by Silicon Graphics, Inc.
6  */
7 #include <linux/kernel.h>
8 #include <linux/mm.h>
9 
10 #include <asm/hazards.h>
11 #include <asm/mipsregs.h>
12 #include <asm/page.h>
13 #include <asm/pgtable.h>
14 #include <asm/tlbdebug.h>
15 
16 static inline const char *msk2str(unsigned int mask)
17 {
18 	switch (mask) {
19 	case PM_4K:	return "4kb";
20 	case PM_16K:	return "16kb";
21 	case PM_64K:	return "64kb";
22 	case PM_256K:	return "256kb";
23 #ifdef CONFIG_CPU_CAVIUM_OCTEON
24 	case PM_8K:	return "8kb";
25 	case PM_32K:	return "32kb";
26 	case PM_128K:	return "128kb";
27 	case PM_512K:	return "512kb";
28 	case PM_2M:	return "2Mb";
29 	case PM_8M:	return "8Mb";
30 	case PM_32M:	return "32Mb";
31 #endif
32 #ifndef CONFIG_CPU_VR41XX
33 	case PM_1M:	return "1Mb";
34 	case PM_4M:	return "4Mb";
35 	case PM_16M:	return "16Mb";
36 	case PM_64M:	return "64Mb";
37 	case PM_256M:	return "256Mb";
38 	case PM_1G:	return "1Gb";
39 #endif
40 	}
41 	return "";
42 }
43 
44 static void dump_tlb(int first, int last)
45 {
46 	unsigned long s_entryhi, entryhi, asid;
47 	unsigned long long entrylo0, entrylo1, pa;
48 	unsigned int s_index, s_pagemask, pagemask, c0, c1, i;
49 #ifdef CONFIG_32BIT
50 	bool xpa = cpu_has_xpa && (read_c0_pagegrain() & PG_ELPA);
51 	int pwidth = xpa ? 11 : 8;
52 	int vwidth = 8;
53 #else
54 	bool xpa = false;
55 	int pwidth = 11;
56 	int vwidth = 11;
57 #endif
58 
59 	s_pagemask = read_c0_pagemask();
60 	s_entryhi = read_c0_entryhi();
61 	s_index = read_c0_index();
62 	asid = s_entryhi & 0xff;
63 
64 	for (i = first; i <= last; i++) {
65 		write_c0_index(i);
66 		mtc0_tlbr_hazard();
67 		tlb_read();
68 		tlb_read_hazard();
69 		pagemask = read_c0_pagemask();
70 		entryhi	 = read_c0_entryhi();
71 		entrylo0 = read_c0_entrylo0();
72 		entrylo1 = read_c0_entrylo1();
73 
74 		/* EHINV bit marks entire entry as invalid */
75 		if (cpu_has_tlbinv && entryhi & MIPS_ENTRYHI_EHINV)
76 			continue;
77 		/*
78 		 * Prior to tlbinv, unused entries have a virtual address of
79 		 * CKSEG0.
80 		 */
81 		if ((entryhi & ~0x1ffffUL) == CKSEG0)
82 			continue;
83 		/*
84 		 * ASID takes effect in absence of G (global) bit.
85 		 * We check both G bits, even though architecturally they should
86 		 * match one another, because some revisions of the SB1 core may
87 		 * leave only a single G bit set after a machine check exception
88 		 * due to duplicate TLB entry.
89 		 */
90 		if (!((entrylo0 | entrylo1) & MIPS_ENTRYLO_G) &&
91 		    (entryhi & 0xff) != asid)
92 			continue;
93 
94 		/*
95 		 * Only print entries in use
96 		 */
97 		printk("Index: %2d pgmask=%s ", i, msk2str(pagemask));
98 
99 		c0 = (entrylo0 & MIPS_ENTRYLO_C) >> MIPS_ENTRYLO_C_SHIFT;
100 		c1 = (entrylo1 & MIPS_ENTRYLO_C) >> MIPS_ENTRYLO_C_SHIFT;
101 
102 		printk("va=%0*lx asid=%02lx\n",
103 		       vwidth, (entryhi & ~0x1fffUL),
104 		       entryhi & 0xff);
105 		/* RI/XI are in awkward places, so mask them off separately */
106 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
107 		if (xpa)
108 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
109 		pa = (pa << 6) & PAGE_MASK;
110 		printk("\t[");
111 		if (cpu_has_rixi)
112 			printk("ri=%d xi=%d ",
113 			       (entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
114 			       (entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
115 		printk("pa=%0*llx c=%d d=%d v=%d g=%d] [",
116 		       pwidth, pa, c0,
117 		       (entrylo0 & MIPS_ENTRYLO_D) ? 1 : 0,
118 		       (entrylo0 & MIPS_ENTRYLO_V) ? 1 : 0,
119 		       (entrylo0 & MIPS_ENTRYLO_G) ? 1 : 0);
120 		/* RI/XI are in awkward places, so mask them off separately */
121 		pa = entrylo1 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
122 		if (xpa)
123 			pa |= (unsigned long long)readx_c0_entrylo1() << 30;
124 		pa = (pa << 6) & PAGE_MASK;
125 		if (cpu_has_rixi)
126 			printk("ri=%d xi=%d ",
127 			       (entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
128 			       (entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
129 		printk("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
130 		       pwidth, pa, c1,
131 		       (entrylo1 & MIPS_ENTRYLO_D) ? 1 : 0,
132 		       (entrylo1 & MIPS_ENTRYLO_V) ? 1 : 0,
133 		       (entrylo1 & MIPS_ENTRYLO_G) ? 1 : 0);
134 	}
135 	printk("\n");
136 
137 	write_c0_entryhi(s_entryhi);
138 	write_c0_index(s_index);
139 	write_c0_pagemask(s_pagemask);
140 }
141 
142 void dump_tlb_all(void)
143 {
144 	dump_tlb(0, current_cpu_data.tlbsize - 1);
145 }
146