xref: /openbmc/linux/arch/mips/lib/dump_tlb.c (revision 2dec9e09)
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/mmu_context.h>
14 #include <asm/page.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 	}
63 	return "";
64 }
65 
66 static void dump_tlb(int first, int last)
67 {
68 	unsigned long s_entryhi, entryhi, asid, mmid;
69 	unsigned long long entrylo0, entrylo1, pa;
70 	unsigned int s_index, s_pagemask, s_guestctl1 = 0;
71 	unsigned int pagemask, guestctl1 = 0, c0, c1, i;
72 	unsigned long asidmask = cpu_asid_mask(&current_cpu_data);
73 	int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4);
74 	unsigned long s_mmid;
75 #ifdef CONFIG_32BIT
76 	bool xpa = cpu_has_xpa && (read_c0_pagegrain() & PG_ELPA);
77 	int pwidth = xpa ? 11 : 8;
78 	int vwidth = 8;
79 #else
80 	bool xpa = false;
81 	int pwidth = 11;
82 	int vwidth = 11;
83 #endif
84 
85 	s_pagemask = read_c0_pagemask();
86 	s_entryhi = read_c0_entryhi();
87 	s_index = read_c0_index();
88 
89 	if (cpu_has_mmid)
90 		asid = s_mmid = read_c0_memorymapid();
91 	else
92 		asid = s_entryhi & asidmask;
93 
94 	if (cpu_has_guestid)
95 		s_guestctl1 = read_c0_guestctl1();
96 
97 	for (i = first; i <= last; i++) {
98 		write_c0_index(i);
99 		mtc0_tlbr_hazard();
100 		tlb_read();
101 		tlb_read_hazard();
102 		pagemask = read_c0_pagemask();
103 		entryhi	 = read_c0_entryhi();
104 		entrylo0 = read_c0_entrylo0();
105 		entrylo1 = read_c0_entrylo1();
106 
107 		if (cpu_has_mmid)
108 			mmid = read_c0_memorymapid();
109 		else
110 			mmid = entryhi & asidmask;
111 
112 		if (cpu_has_guestid)
113 			guestctl1 = read_c0_guestctl1();
114 
115 		/* EHINV bit marks entire entry as invalid */
116 		if (cpu_has_tlbinv && entryhi & MIPS_ENTRYHI_EHINV)
117 			continue;
118 		/*
119 		 * Prior to tlbinv, unused entries have a virtual address of
120 		 * CKSEG0.
121 		 */
122 		if ((entryhi & ~0x1ffffUL) == CKSEG0)
123 			continue;
124 		/*
125 		 * ASID takes effect in absence of G (global) bit.
126 		 * We check both G bits, even though architecturally they should
127 		 * match one another, because some revisions of the SB1 core may
128 		 * leave only a single G bit set after a machine check exception
129 		 * due to duplicate TLB entry.
130 		 */
131 		if (!((entrylo0 | entrylo1) & ENTRYLO_G) && (mmid != asid))
132 			continue;
133 
134 		/*
135 		 * Only print entries in use
136 		 */
137 		printk("Index: %2d pgmask=%s ", i, msk2str(pagemask));
138 
139 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
140 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
141 
142 		pr_cont("va=%0*lx asid=%0*lx",
143 			vwidth, (entryhi & ~0x1fffUL),
144 			asidwidth, mmid);
145 		if (cpu_has_guestid)
146 			pr_cont(" gid=%02lx",
147 				(guestctl1 & MIPS_GCTL1_RID)
148 					>> MIPS_GCTL1_RID_SHIFT);
149 		/* RI/XI are in awkward places, so mask them off separately */
150 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
151 		if (xpa)
152 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
153 		pa = (pa << 6) & PAGE_MASK;
154 		pr_cont("\n\t[");
155 		if (cpu_has_rixi)
156 			pr_cont("ri=%d xi=%d ",
157 				(entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
158 				(entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
159 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d] [",
160 			pwidth, pa, c0,
161 			(entrylo0 & ENTRYLO_D) ? 1 : 0,
162 			(entrylo0 & ENTRYLO_V) ? 1 : 0,
163 			(entrylo0 & ENTRYLO_G) ? 1 : 0);
164 		/* RI/XI are in awkward places, so mask them off separately */
165 		pa = entrylo1 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
166 		if (xpa)
167 			pa |= (unsigned long long)readx_c0_entrylo1() << 30;
168 		pa = (pa << 6) & PAGE_MASK;
169 		if (cpu_has_rixi)
170 			pr_cont("ri=%d xi=%d ",
171 				(entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
172 				(entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
173 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
174 			pwidth, pa, c1,
175 			(entrylo1 & ENTRYLO_D) ? 1 : 0,
176 			(entrylo1 & ENTRYLO_V) ? 1 : 0,
177 			(entrylo1 & ENTRYLO_G) ? 1 : 0);
178 	}
179 	printk("\n");
180 
181 	write_c0_entryhi(s_entryhi);
182 	write_c0_index(s_index);
183 	write_c0_pagemask(s_pagemask);
184 	if (cpu_has_guestid)
185 		write_c0_guestctl1(s_guestctl1);
186 }
187 
188 void dump_tlb_all(void)
189 {
190 	dump_tlb(0, current_cpu_data.tlbsize - 1);
191 }
192