xref: /openbmc/linux/arch/loongarch/lib/dump_tlb.c (revision 7effbd18)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  *
5  * Derived from MIPS:
6  * Copyright (C) 1994, 1995 by Waldorf Electronics, written by Ralf Baechle.
7  * Copyright (C) 1999 by Silicon Graphics, Inc.
8  */
9 #include <linux/kernel.h>
10 #include <linux/mm.h>
11 
12 #include <asm/loongarch.h>
13 #include <asm/page.h>
14 #include <asm/pgtable.h>
15 #include <asm/tlb.h>
16 
17 void dump_tlb_regs(void)
18 {
19 	const int field = 2 * sizeof(unsigned long);
20 
21 	pr_info("Index    : 0x%0x\n", read_csr_tlbidx());
22 	pr_info("PageSize : 0x%0x\n", read_csr_pagesize());
23 	pr_info("EntryHi  : 0x%0*llx\n", field, read_csr_entryhi());
24 	pr_info("EntryLo0 : 0x%0*llx\n", field, read_csr_entrylo0());
25 	pr_info("EntryLo1 : 0x%0*llx\n", field, read_csr_entrylo1());
26 }
27 
28 static void dump_tlb(int first, int last)
29 {
30 	unsigned long s_entryhi, entryhi, asid;
31 	unsigned long long entrylo0, entrylo1, pa;
32 	unsigned int index;
33 	unsigned int s_index, s_asid;
34 	unsigned int pagesize, c0, c1, i;
35 	unsigned long asidmask = cpu_asid_mask(&current_cpu_data);
36 	int pwidth = 16;
37 	int vwidth = 16;
38 	int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4);
39 
40 	s_entryhi = read_csr_entryhi();
41 	s_index = read_csr_tlbidx();
42 	s_asid = read_csr_asid();
43 
44 	for (i = first; i <= last; i++) {
45 		write_csr_index(i);
46 		tlb_read();
47 		pagesize = read_csr_pagesize();
48 		entryhi	 = read_csr_entryhi();
49 		entrylo0 = read_csr_entrylo0();
50 		entrylo1 = read_csr_entrylo1();
51 		index = read_csr_tlbidx();
52 		asid = read_csr_asid();
53 
54 		/* EHINV bit marks entire entry as invalid */
55 		if (index & CSR_TLBIDX_EHINV)
56 			continue;
57 		/*
58 		 * ASID takes effect in absence of G (global) bit.
59 		 */
60 		if (!((entrylo0 | entrylo1) & ENTRYLO_G) &&
61 		    asid != s_asid)
62 			continue;
63 
64 		/*
65 		 * Only print entries in use
66 		 */
67 		pr_info("Index: %4d pgsize=0x%x ", i, (1 << pagesize));
68 
69 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
70 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
71 
72 		pr_cont("va=0x%0*lx asid=0x%0*lx",
73 			vwidth, (entryhi & ~0x1fffUL), asidwidth, asid & asidmask);
74 
75 		/* NR/NX are in awkward places, so mask them off separately */
76 		pa = entrylo0 & ~(ENTRYLO_NR | ENTRYLO_NX);
77 		pa = pa & PAGE_MASK;
78 		pr_cont("\n\t[");
79 		pr_cont("nr=%d nx=%d ",
80 			(entrylo0 & ENTRYLO_NR) ? 1 : 0,
81 			(entrylo0 & ENTRYLO_NX) ? 1 : 0);
82 		pr_cont("pa=0x%0*llx c=%d d=%d v=%d g=%d plv=%lld] [",
83 			pwidth, pa, c0,
84 			(entrylo0 & ENTRYLO_D) ? 1 : 0,
85 			(entrylo0 & ENTRYLO_V) ? 1 : 0,
86 			(entrylo0 & ENTRYLO_G) ? 1 : 0,
87 			(entrylo0 & ENTRYLO_PLV) >> ENTRYLO_PLV_SHIFT);
88 		/* NR/NX are in awkward places, so mask them off separately */
89 		pa = entrylo1 & ~(ENTRYLO_NR | ENTRYLO_NX);
90 		pa = pa & PAGE_MASK;
91 		pr_cont("nr=%d nx=%d ",
92 			(entrylo1 & ENTRYLO_NR) ? 1 : 0,
93 			(entrylo1 & ENTRYLO_NX) ? 1 : 0);
94 		pr_cont("pa=0x%0*llx c=%d d=%d v=%d g=%d plv=%lld]\n",
95 			pwidth, pa, c1,
96 			(entrylo1 & ENTRYLO_D) ? 1 : 0,
97 			(entrylo1 & ENTRYLO_V) ? 1 : 0,
98 			(entrylo1 & ENTRYLO_G) ? 1 : 0,
99 			(entrylo1 & ENTRYLO_PLV) >> ENTRYLO_PLV_SHIFT);
100 	}
101 	pr_info("\n");
102 
103 	write_csr_entryhi(s_entryhi);
104 	write_csr_tlbidx(s_index);
105 	write_csr_asid(s_asid);
106 }
107 
108 void dump_tlb_all(void)
109 {
110 	dump_tlb(0, current_cpu_data.tlbsize - 1);
111 }
112