1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Firmware-Assisted Dump support on POWER platform (OPAL).
4 *
5 * Copyright 2019, Hari Bathini, IBM Corporation.
6 */
7
8 #ifndef _POWERNV_OPAL_FADUMP_H
9 #define _POWERNV_OPAL_FADUMP_H
10
11 #include <asm/reg.h>
12
13 /*
14 * With kernel & initrd loaded at 512MB (with 256MB size), enforce a minimum
15 * boot memory size of 768MB to ensure f/w loading kernel and initrd doesn't
16 * mess with crash'ed kernel's memory during MPIPL.
17 */
18 #define OPAL_FADUMP_MIN_BOOT_MEM (0x30000000UL)
19
20 /*
21 * OPAL FADump metadata structure format version
22 *
23 * OPAL FADump kernel metadata structure stores kernel metadata needed to
24 * register-for/process crash dump. Format version is used to keep a tab on
25 * the changes in the structure format. The changes, if any, to the format
26 * are expected to be minimal and backward compatible.
27 */
28 #define OPAL_FADUMP_VERSION 0x1
29
30 /*
31 * OPAL FADump kernel metadata
32 *
33 * The address of this structure will be registered with f/w for retrieving
34 * and processing during crash dump.
35 */
36 struct opal_fadump_mem_struct {
37 u8 version;
38 u8 reserved[3];
39 u16 region_cnt; /* number of regions */
40 u16 registered_regions; /* Regions registered for MPIPL */
41 u64 fadumphdr_addr;
42 struct opal_mpipl_region rgn[FADUMP_MAX_MEM_REGS];
43 } __packed;
44
45 /*
46 * CPU state data
47 *
48 * CPU state data information is provided by f/w. The format for this data
49 * is defined in the HDAT spec. Version is used to keep a tab on the changes
50 * in this CPU state data format. Changes to this format are unlikely, but
51 * if there are any changes, please refer to latest HDAT specification.
52 */
53 #define HDAT_FADUMP_CPU_DATA_VER 1
54
55 #define HDAT_FADUMP_CORE_INACTIVE (0x0F)
56
57 /* HDAT thread header for register entries */
58 struct hdat_fadump_thread_hdr {
59 __be32 pir;
60 /* 0x00 - 0x0F - The corresponding stop state of the core */
61 u8 core_state;
62 u8 reserved[3];
63
64 __be32 offset; /* Offset to Register Entries array */
65 __be32 ecnt; /* Number of entries */
66 __be32 esize; /* Alloc size of each array entry in bytes */
67 __be32 eactsz; /* Actual size of each array entry in bytes */
68 } __packed;
69
70 /* Register types populated by f/w */
71 #define HDAT_FADUMP_REG_TYPE_GPR 0x01
72 #define HDAT_FADUMP_REG_TYPE_SPR 0x02
73
74 /* ID numbers used by f/w while populating certain registers */
75 #define HDAT_FADUMP_REG_ID_NIP 0x7D0
76 #define HDAT_FADUMP_REG_ID_MSR 0x7D1
77 #define HDAT_FADUMP_REG_ID_CCR 0x7D2
78
79 /* HDAT register entry. */
80 struct hdat_fadump_reg_entry {
81 __be32 reg_type;
82 __be32 reg_num;
83 __be64 reg_val;
84 } __packed;
85
86 static inline void opal_fadump_set_regval_regnum(struct pt_regs *regs,
87 u32 reg_type, u32 reg_num,
88 u64 reg_val)
89 {
90 if (reg_type == HDAT_FADUMP_REG_TYPE_GPR) {
91 if (reg_num < 32)
92 regs->gpr[reg_num] = reg_val;
93 return;
94 }
95
96 switch (reg_num) {
97 case SPRN_CTR:
98 regs->ctr = reg_val;
99 break;
100 case SPRN_LR:
101 regs->link = reg_val;
102 break;
103 case SPRN_XER:
104 regs->xer = reg_val;
105 break;
106 case SPRN_DAR:
107 regs->dar = reg_val;
108 break;
109 case SPRN_DSISR:
110 regs->dsisr = reg_val;
111 break;
112 case HDAT_FADUMP_REG_ID_NIP:
113 regs->nip = reg_val;
114 break;
115 case HDAT_FADUMP_REG_ID_MSR:
116 regs->msr = reg_val;
117 break;
118 case HDAT_FADUMP_REG_ID_CCR:
119 regs->ccr = reg_val;
120 break;
121 }
122 }
123
124 static inline void opal_fadump_read_regs(char *bufp, unsigned int regs_cnt,
125 unsigned int reg_entry_size,
126 bool cpu_endian,
127 struct pt_regs *regs)
128 {
129 struct hdat_fadump_reg_entry *reg_entry;
130 u64 val;
131 int i;
132
133 memset(regs, 0, sizeof(struct pt_regs));
134
135 for (i = 0; i < regs_cnt; i++, bufp += reg_entry_size) {
136 reg_entry = (struct hdat_fadump_reg_entry *)bufp;
137 val = (cpu_endian ? be64_to_cpu(reg_entry->reg_val) :
138 reg_entry->reg_val);
139 opal_fadump_set_regval_regnum(regs,
140 be32_to_cpu(reg_entry->reg_type),
141 be32_to_cpu(reg_entry->reg_num),
142 val);
143 }
144 }
145
146 #endif /* _POWERNV_OPAL_FADUMP_H */