xref: /openbmc/linux/arch/mips/lib/dump_tlb.c (revision 3dc4b6fb)
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/pgtable.h>
16 #include <asm/tlbdebug.h>
17 
18 void dump_tlb_regs(void)
19 {
20 	const int field = 2 * sizeof(unsigned long);
21 
22 	pr_info("Index    : %0x\n", read_c0_index());
23 	pr_info("PageMask : %0x\n", read_c0_pagemask());
24 	if (cpu_has_guestid)
25 		pr_info("GuestCtl1: %0x\n", read_c0_guestctl1());
26 	pr_info("EntryHi  : %0*lx\n", field, read_c0_entryhi());
27 	pr_info("EntryLo0 : %0*lx\n", field, read_c0_entrylo0());
28 	pr_info("EntryLo1 : %0*lx\n", field, read_c0_entrylo1());
29 	pr_info("Wired    : %0x\n", read_c0_wired());
30 	switch (current_cpu_type()) {
31 	case CPU_R10000:
32 	case CPU_R12000:
33 	case CPU_R14000:
34 	case CPU_R16000:
35 		pr_info("FrameMask: %0x\n", read_c0_framemask());
36 		break;
37 	}
38 	if (cpu_has_small_pages || cpu_has_rixi || cpu_has_xpa)
39 		pr_info("PageGrain: %0x\n", read_c0_pagegrain());
40 	if (cpu_has_htw) {
41 		pr_info("PWField  : %0*lx\n", field, read_c0_pwfield());
42 		pr_info("PWSize   : %0*lx\n", field, read_c0_pwsize());
43 		pr_info("PWCtl    : %0x\n", read_c0_pwctl());
44 	}
45 }
46 
47 static inline const char *msk2str(unsigned int mask)
48 {
49 	switch (mask) {
50 	case PM_4K:	return "4kb";
51 	case PM_16K:	return "16kb";
52 	case PM_64K:	return "64kb";
53 	case PM_256K:	return "256kb";
54 #ifdef CONFIG_CPU_CAVIUM_OCTEON
55 	case PM_8K:	return "8kb";
56 	case PM_32K:	return "32kb";
57 	case PM_128K:	return "128kb";
58 	case PM_512K:	return "512kb";
59 	case PM_2M:	return "2Mb";
60 	case PM_8M:	return "8Mb";
61 	case PM_32M:	return "32Mb";
62 #endif
63 #ifndef CONFIG_CPU_VR41XX
64 	case PM_1M:	return "1Mb";
65 	case PM_4M:	return "4Mb";
66 	case PM_16M:	return "16Mb";
67 	case PM_64M:	return "64Mb";
68 	case PM_256M:	return "256Mb";
69 	case PM_1G:	return "1Gb";
70 #endif
71 	}
72 	return "";
73 }
74 
75 static void dump_tlb(int first, int last)
76 {
77 	unsigned long s_entryhi, entryhi, asid, mmid;
78 	unsigned long long entrylo0, entrylo1, pa;
79 	unsigned int s_index, s_pagemask, s_guestctl1 = 0;
80 	unsigned int pagemask, guestctl1 = 0, c0, c1, i;
81 	unsigned long asidmask = cpu_asid_mask(&current_cpu_data);
82 	int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4);
83 	unsigned long uninitialized_var(s_mmid);
84 #ifdef CONFIG_32BIT
85 	bool xpa = cpu_has_xpa && (read_c0_pagegrain() & PG_ELPA);
86 	int pwidth = xpa ? 11 : 8;
87 	int vwidth = 8;
88 #else
89 	bool xpa = false;
90 	int pwidth = 11;
91 	int vwidth = 11;
92 #endif
93 
94 	s_pagemask = read_c0_pagemask();
95 	s_entryhi = read_c0_entryhi();
96 	s_index = read_c0_index();
97 
98 	if (cpu_has_mmid)
99 		asid = s_mmid = read_c0_memorymapid();
100 	else
101 		asid = s_entryhi & asidmask;
102 
103 	if (cpu_has_guestid)
104 		s_guestctl1 = read_c0_guestctl1();
105 
106 	for (i = first; i <= last; i++) {
107 		write_c0_index(i);
108 		mtc0_tlbr_hazard();
109 		tlb_read();
110 		tlb_read_hazard();
111 		pagemask = read_c0_pagemask();
112 		entryhi	 = read_c0_entryhi();
113 		entrylo0 = read_c0_entrylo0();
114 		entrylo1 = read_c0_entrylo1();
115 
116 		if (cpu_has_mmid)
117 			mmid = read_c0_memorymapid();
118 		else
119 			mmid = entryhi & asidmask;
120 
121 		if (cpu_has_guestid)
122 			guestctl1 = read_c0_guestctl1();
123 
124 		/* EHINV bit marks entire entry as invalid */
125 		if (cpu_has_tlbinv && entryhi & MIPS_ENTRYHI_EHINV)
126 			continue;
127 		/*
128 		 * Prior to tlbinv, unused entries have a virtual address of
129 		 * CKSEG0.
130 		 */
131 		if ((entryhi & ~0x1ffffUL) == CKSEG0)
132 			continue;
133 		/*
134 		 * ASID takes effect in absence of G (global) bit.
135 		 * We check both G bits, even though architecturally they should
136 		 * match one another, because some revisions of the SB1 core may
137 		 * leave only a single G bit set after a machine check exception
138 		 * due to duplicate TLB entry.
139 		 */
140 		if (!((entrylo0 | entrylo1) & ENTRYLO_G) && (mmid != asid))
141 			continue;
142 
143 		/*
144 		 * Only print entries in use
145 		 */
146 		printk("Index: %2d pgmask=%s ", i, msk2str(pagemask));
147 
148 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
149 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
150 
151 		pr_cont("va=%0*lx asid=%0*lx",
152 			vwidth, (entryhi & ~0x1fffUL),
153 			asidwidth, mmid);
154 		if (cpu_has_guestid)
155 			pr_cont(" gid=%02lx",
156 				(guestctl1 & MIPS_GCTL1_RID)
157 					>> MIPS_GCTL1_RID_SHIFT);
158 		/* RI/XI are in awkward places, so mask them off separately */
159 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
160 		if (xpa)
161 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
162 		pa = (pa << 6) & PAGE_MASK;
163 		pr_cont("\n\t[");
164 		if (cpu_has_rixi)
165 			pr_cont("ri=%d xi=%d ",
166 				(entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
167 				(entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
168 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d] [",
169 			pwidth, pa, c0,
170 			(entrylo0 & ENTRYLO_D) ? 1 : 0,
171 			(entrylo0 & ENTRYLO_V) ? 1 : 0,
172 			(entrylo0 & ENTRYLO_G) ? 1 : 0);
173 		/* RI/XI are in awkward places, so mask them off separately */
174 		pa = entrylo1 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
175 		if (xpa)
176 			pa |= (unsigned long long)readx_c0_entrylo1() << 30;
177 		pa = (pa << 6) & PAGE_MASK;
178 		if (cpu_has_rixi)
179 			pr_cont("ri=%d xi=%d ",
180 				(entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
181 				(entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
182 		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
183 			pwidth, pa, c1,
184 			(entrylo1 & ENTRYLO_D) ? 1 : 0,
185 			(entrylo1 & ENTRYLO_V) ? 1 : 0,
186 			(entrylo1 & ENTRYLO_G) ? 1 : 0);
187 	}
188 	printk("\n");
189 
190 	write_c0_entryhi(s_entryhi);
191 	write_c0_index(s_index);
192 	write_c0_pagemask(s_pagemask);
193 	if (cpu_has_guestid)
194 		write_c0_guestctl1(s_guestctl1);
195 }
196 
197 void dump_tlb_all(void)
198 {
199 	dump_tlb(0, current_cpu_data.tlbsize - 1);
200 }
201