xref: /openbmc/linux/arch/mips/lib/r3k_dump_tlb.c (revision 8dd3cdea)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Dump R3000 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  * Copyright (C) 1999 by Harald Koerfgen
8  */
9 #include <linux/kernel.h>
10 #include <linux/mm.h>
11 
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 	pr_info("Index    : %0x\n", read_c0_index());
20 	pr_info("EntryHi  : %0lx\n", read_c0_entryhi());
21 	pr_info("EntryLo  : %0lx\n", read_c0_entrylo0());
22 }
23 
24 static void dump_tlb(int first, int last)
25 {
26 	int	i;
27 	unsigned int asid;
28 	unsigned long entryhi, entrylo0, asid_mask;
29 
30 	asid_mask = cpu_asid_mask(&current_cpu_data);
31 	asid = read_c0_entryhi() & asid_mask;
32 
33 	for (i = first; i <= last; i++) {
34 		write_c0_index(i<<8);
35 		__asm__ __volatile__(
36 			".set\tnoreorder\n\t"
37 			"tlbr\n\t"
38 			"nop\n\t"
39 			".set\treorder");
40 		entryhi	 = read_c0_entryhi();
41 		entrylo0 = read_c0_entrylo0();
42 
43 		/* Unused entries have a virtual address of KSEG0.  */
44 		if ((entryhi & PAGE_MASK) != KSEG0 &&
45 		    (entrylo0 & R3K_ENTRYLO_G ||
46 		     (entryhi & asid_mask) == asid)) {
47 			/*
48 			 * Only print entries in use
49 			 */
50 			printk("Index: %2d ", i);
51 
52 			pr_cont("va=%08lx asid=%08lx"
53 				"  [pa=%06lx n=%d d=%d v=%d g=%d]",
54 				entryhi & PAGE_MASK,
55 				entryhi & asid_mask,
56 				entrylo0 & PAGE_MASK,
57 				(entrylo0 & R3K_ENTRYLO_N) ? 1 : 0,
58 				(entrylo0 & R3K_ENTRYLO_D) ? 1 : 0,
59 				(entrylo0 & R3K_ENTRYLO_V) ? 1 : 0,
60 				(entrylo0 & R3K_ENTRYLO_G) ? 1 : 0);
61 		}
62 	}
63 	printk("\n");
64 
65 	write_c0_entryhi(asid);
66 }
67 
68 void dump_tlb_all(void)
69 {
70 	dump_tlb(0, current_cpu_data.tlbsize - 1);
71 }
72