xref: /openbmc/linux/arch/mips/lib/dump_tlb.c (revision 65417d9f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Dump R4x00 TLB for debugging purposes.
4  *
5  * Copyright (C) 1994, 1995 by Waldorf Electronics, written by Ralf Baechle.
6  * Copyright (C) 1999 by Silicon Graphics, Inc.
7  */
8 #include <linux/kernel.h>
9 #include <linux/mm.h>
10 
11 #include <asm/hazards.h>
12 #include <asm/mipsregs.h>
13 #include <asm/page.h>
14 #include <asm/pgtable.h>
15 #include <asm/tlbdebug.h>
16 
17 void dump_tlb_regs(void)
18 {
19 	const int field = 2 * sizeof(unsigned long);
20 
21 	pr_info("Index    : %0x\n", read_c0_index());
22 	pr_info("PageMask : %0x\n", read_c0_pagemask());
23 	if (cpu_has_guestid)
24 		pr_info("GuestCtl1: %0x\n", read_c0_guestctl1());
25 	pr_info("EntryHi  : %0*lx\n", field, read_c0_entryhi());
26 	pr_info("EntryLo0 : %0*lx\n", field, read_c0_entrylo0());
27 	pr_info("EntryLo1 : %0*lx\n", field, read_c0_entrylo1());
28 	pr_info("Wired    : %0x\n", read_c0_wired());
29 	switch (current_cpu_type()) {
30 	case CPU_R10000:
31 	case CPU_R12000:
32 	case CPU_R14000:
33 	case CPU_R16000:
34 		pr_info("FrameMask: %0x\n", read_c0_framemask());
35 		break;
36 	}
37 	if (cpu_has_small_pages || cpu_has_rixi || cpu_has_xpa)
38 		pr_info("PageGrain: %0x\n", read_c0_pagegrain());
39 	if (cpu_has_htw) {
40 		pr_info("PWField  : %0*lx\n", field, read_c0_pwfield());
41 		pr_info("PWSize   : %0*lx\n", field, read_c0_pwsize());
42 		pr_info("PWCtl    : %0x\n", read_c0_pwctl());
43 	}
44 }
45 
46 static inline const char *msk2str(unsigned int mask)
47 {
48 	switch (mask) {
49 	case PM_4K:	return "4kb";
50 	case PM_16K:	return "16kb";
51 	case PM_64K:	return "64kb";
52 	case PM_256K:	return "256kb";
53 #ifdef CONFIG_CPU_CAVIUM_OCTEON
54 	case PM_8K:	return "8kb";
55 	case PM_32K:	return "32kb";
56 	case PM_128K:	return "128kb";
57 	case PM_512K:	return "512kb";
58 	case PM_2M:	return "2Mb";
59 	case PM_8M:	return "8Mb";
60 	case PM_32M:	return "32Mb";
61 #endif
62 #ifndef CONFIG_CPU_VR41XX
63 	case PM_1M:	return "1Mb";
64 	case PM_4M:	return "4Mb";
65 	case PM_16M:	return "16Mb";
66 	case PM_64M:	return "64Mb";
67 	case PM_256M:	return "256Mb";
68 	case PM_1G:	return "1Gb";
69 #endif
70 	}
71 	return "";
72 }
73 
74 static void dump_tlb(int first, int last)
75 {
76 	unsigned long s_entryhi, entryhi, asid;
77 	unsigned long long entrylo0, entrylo1, pa;
78 	unsigned int s_index, s_pagemask, s_guestctl1 = 0;
79 	unsigned int pagemask, guestctl1 = 0, c0, c1, i;
80 	unsigned long asidmask = cpu_asid_mask(&current_cpu_data);
81 	int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4);
82 #ifdef CONFIG_32BIT
83 	bool xpa = cpu_has_xpa && (read_c0_pagegrain() & PG_ELPA);
84 	int pwidth = xpa ? 11 : 8;
85 	int vwidth = 8;
86 #else
87 	bool xpa = false;
88 	int pwidth = 11;
89 	int vwidth = 11;
90 #endif
91 
92 	s_pagemask = read_c0_pagemask();
93 	s_entryhi = read_c0_entryhi();
94 	s_index = read_c0_index();
95 	asid = s_entryhi & asidmask;
96 	if (cpu_has_guestid)
97 		s_guestctl1 = read_c0_guestctl1();
98 
99 	for (i = first; i <= last; i++) {
100 		write_c0_index(i);
101 		mtc0_tlbr_hazard();
102 		tlb_read();
103 		tlb_read_hazard();
104 		pagemask = read_c0_pagemask();
105 		entryhi	 = read_c0_entryhi();
106 		entrylo0 = read_c0_entrylo0();
107 		entrylo1 = read_c0_entrylo1();
108 		if (cpu_has_guestid)
109 			guestctl1 = read_c0_guestctl1();
110 
111 		/* EHINV bit marks entire entry as invalid */
112 		if (cpu_has_tlbinv && entryhi & MIPS_ENTRYHI_EHINV)
113 			continue;
114 		/*
115 		 * Prior to tlbinv, unused entries have a virtual address of
116 		 * CKSEG0.
117 		 */
118 		if ((entryhi & ~0x1ffffUL) == CKSEG0)
119 			continue;
120 		/*
121 		 * ASID takes effect in absence of G (global) bit.
122 		 * We check both G bits, even though architecturally they should
123 		 * match one another, because some revisions of the SB1 core may
124 		 * leave only a single G bit set after a machine check exception
125 		 * due to duplicate TLB entry.
126 		 */
127 		if (!((entrylo0 | entrylo1) & ENTRYLO_G) &&
128 		    (entryhi & asidmask) != asid)
129 			continue;
130 
131 		/*
132 		 * Only print entries in use
133 		 */
134 		printk("Index: %2d pgmask=%s ", i, msk2str(pagemask));
135 
136 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
137 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
138 
139 		pr_cont("va=%0*lx asid=%0*lx",
140 			vwidth, (entryhi & ~0x1fffUL),
141 			asidwidth, entryhi & asidmask);
142 		if (cpu_has_guestid)
143 			pr_cont(" gid=%02lx",
144 				(guestctl1 & MIPS_GCTL1_RID)
145 					>> MIPS_GCTL1_RID_SHIFT);
146 		/* RI/XI are in awkward places, so mask them off separately */
147 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
148 		if (xpa)
149 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
150 		pa = (pa << 6) & PAGE_MASK;
151 		pr_cont("\n\t[");
152 		if (cpu_has_rixi)
153 			pr_cont("ri=%d xi=%d ",
154 				(entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
155 				(entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
156 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d] [",
157 			pwidth, pa, c0,
158 			(entrylo0 & ENTRYLO_D) ? 1 : 0,
159 			(entrylo0 & ENTRYLO_V) ? 1 : 0,
160 			(entrylo0 & ENTRYLO_G) ? 1 : 0);
161 		/* RI/XI are in awkward places, so mask them off separately */
162 		pa = entrylo1 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
163 		if (xpa)
164 			pa |= (unsigned long long)readx_c0_entrylo1() << 30;
165 		pa = (pa << 6) & PAGE_MASK;
166 		if (cpu_has_rixi)
167 			pr_cont("ri=%d xi=%d ",
168 				(entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
169 				(entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
170 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
171 			pwidth, pa, c1,
172 			(entrylo1 & ENTRYLO_D) ? 1 : 0,
173 			(entrylo1 & ENTRYLO_V) ? 1 : 0,
174 			(entrylo1 & ENTRYLO_G) ? 1 : 0);
175 	}
176 	printk("\n");
177 
178 	write_c0_entryhi(s_entryhi);
179 	write_c0_index(s_index);
180 	write_c0_pagemask(s_pagemask);
181 	if (cpu_has_guestid)
182 		write_c0_guestctl1(s_guestctl1);
183 }
184 
185 void dump_tlb_all(void)
186 {
187 	dump_tlb(0, current_cpu_data.tlbsize - 1);
188 }
189