xref: /openbmc/u-boot/arch/mips/lib/traps.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle
4  * Copyright (C) 1995, 1996 Paul M. Antoine
5  * Copyright (C) 1998 Ulf Carlsson
6  * Copyright (C) 1999 Silicon Graphics, Inc.
7  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
8  * Copyright (C) 2002, 2003, 2004, 2005, 2007  Maciej W. Rozycki
9  * Copyright (C) 2000, 2001, 2012 MIPS Technologies, Inc.  All rights reserved.
10  * Copyright (C) 2014, Imagination Technologies Ltd.
11  */
12 
13 #include <common.h>
14 #include <asm/mipsregs.h>
15 #include <asm/addrspace.h>
16 #include <asm/system.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 static void show_regs(const struct pt_regs *regs)
21 {
22 	const int field = 2 * sizeof(unsigned long);
23 	unsigned int cause = regs->cp0_cause;
24 	unsigned int exccode;
25 	int i;
26 
27 	/*
28 	 * Saved main processor registers
29 	 */
30 	for (i = 0; i < 32; ) {
31 		if ((i % 4) == 0)
32 			printf("$%2d   :", i);
33 		if (i == 0)
34 			printf(" %0*lx", field, 0UL);
35 		else if (i == 26 || i == 27)
36 			printf(" %*s", field, "");
37 		else
38 			printf(" %0*lx", field, regs->regs[i]);
39 
40 		i++;
41 		if ((i % 4) == 0)
42 			puts("\n");
43 	}
44 
45 	printf("Hi    : %0*lx\n", field, regs->hi);
46 	printf("Lo    : %0*lx\n", field, regs->lo);
47 
48 	/*
49 	 * Saved cp0 registers
50 	 */
51 	printf("epc   : %0*lx (text %0*lx)\n", field, regs->cp0_epc,
52 	       field, regs->cp0_epc - gd->reloc_off);
53 	printf("ra    : %0*lx (text %0*lx)\n", field, regs->regs[31],
54 	       field, regs->regs[31] - gd->reloc_off);
55 
56 	printf("Status: %08x\n", (uint32_t) regs->cp0_status);
57 
58 	exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
59 	printf("Cause : %08x (ExcCode %02x)\n", cause, exccode);
60 
61 	if (1 <= exccode && exccode <= 5)
62 		printf("BadVA : %0*lx\n", field, regs->cp0_badvaddr);
63 
64 	printf("PrId  : %08x\n", read_c0_prid());
65 }
66 
67 void do_reserved(const struct pt_regs *regs)
68 {
69 	puts("\nOoops:\n");
70 	show_regs(regs);
71 	hang();
72 }
73 
74 void do_ejtag_debug(const struct pt_regs *regs)
75 {
76 	const int field = 2 * sizeof(unsigned long);
77 	unsigned long depc;
78 	unsigned int debug;
79 
80 	depc = read_c0_depc();
81 	debug = read_c0_debug();
82 
83 	printf("SDBBP EJTAG debug exception: c0_depc = %0*lx, DEBUG = %08x\n",
84 	       field, depc, debug);
85 }
86 
87 static void set_handler(unsigned long offset, void *addr, unsigned long size)
88 {
89 	unsigned long ebase = gd->irq_sp;
90 
91 	memcpy((void *)(ebase + offset), addr, size);
92 	flush_cache(ebase + offset, size);
93 }
94 
95 void trap_init(ulong reloc_addr)
96 {
97 	unsigned long ebase = gd->irq_sp;
98 
99 	set_handler(0x180, &except_vec3_generic, 0x80);
100 	set_handler(0x280, &except_vec_ejtag_debug, 0x80);
101 
102 	write_c0_ebase(ebase);
103 	clear_c0_status(ST0_BEV);
104 	execution_hazard_barrier();
105 }
106