1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Firmware-Assisted Dump support on POWERVM platform.
4 *
5 * Copyright 2011, Mahesh Salgaonkar, IBM Corporation.
6 * Copyright 2019, Hari Bathini, IBM Corporation.
7 */
8
9#ifndef _PSERIES_RTAS_FADUMP_H
10#define _PSERIES_RTAS_FADUMP_H
11
12/*
13 * On some Power systems where RMO is 128MB, it still requires minimum of
14 * 256MB for kernel to boot successfully. When kdump infrastructure is
15 * configured to save vmcore over network, we run into OOM issue while
16 * loading modules related to network setup. Hence we need additional 64M
17 * of memory to avoid OOM issue.
18 */
19#define RTAS_FADUMP_MIN_BOOT_MEM	((0x1UL << 28) + (0x1UL << 26))
20
21/* Firmware provided dump sections */
22#define RTAS_FADUMP_CPU_STATE_DATA	0x0001
23#define RTAS_FADUMP_HPTE_REGION		0x0002
24#define RTAS_FADUMP_REAL_MODE_REGION	0x0011
25
26/* Dump request flag */
27#define RTAS_FADUMP_REQUEST_FLAG	0x00000001
28
29/* Dump status flag */
30#define RTAS_FADUMP_ERROR_FLAG		0x2000
31
32/* Kernel Dump section info */
33struct rtas_fadump_section {
34	__be32	request_flag;
35	__be16	source_data_type;
36	__be16	error_flags;
37	__be64	source_address;
38	__be64	source_len;
39	__be64	bytes_dumped;
40	__be64	destination_address;
41};
42
43/* ibm,configure-kernel-dump header. */
44struct rtas_fadump_section_header {
45	__be32	dump_format_version;
46	__be16	dump_num_sections;
47	__be16	dump_status_flag;
48	__be32	offset_first_dump_section;
49
50	/* Fields for disk dump option. */
51	__be32	dd_block_size;
52	__be64	dd_block_offset;
53	__be64	dd_num_blocks;
54	__be32	dd_offset_disk_path;
55
56	/* Maximum time allowed to prevent an automatic dump-reboot. */
57	__be32	max_time_auto;
58};
59
60/*
61 * Firmware Assisted dump memory structure. This structure is required for
62 * registering future kernel dump with power firmware through rtas call.
63 *
64 * No disk dump option. Hence disk dump path string section is not included.
65 */
66struct rtas_fadump_mem_struct {
67	struct rtas_fadump_section_header	header;
68
69	/* Kernel dump sections */
70	struct rtas_fadump_section		cpu_state_data;
71	struct rtas_fadump_section		hpte_region;
72
73	/*
74	 * TODO: Extend multiple boot memory regions support in the kernel
75	 *       for this platform.
76	 */
77	struct rtas_fadump_section		rmr_region;
78};
79
80/*
81 * The firmware-assisted dump format.
82 *
83 * The register save area is an area in the partition's memory used to preserve
84 * the register contents (CPU state data) for the active CPUs during a firmware
85 * assisted dump. The dump format contains register save area header followed
86 * by register entries. Each list of registers for a CPU starts with "CPUSTRT"
87 * and ends with "CPUEND".
88 */
89
90/* Register save area header. */
91struct rtas_fadump_reg_save_area_header {
92	__be64		magic_number;
93	__be32		version;
94	__be32		num_cpu_offset;
95};
96
97/* Register entry. */
98struct rtas_fadump_reg_entry {
99	__be64		reg_id;
100	__be64		reg_value;
101};
102
103/* Utility macros */
104#define RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry)				\
105({									\
106	while (be64_to_cpu(reg_entry->reg_id) !=			\
107	       fadump_str_to_u64("CPUEND"))				\
108		reg_entry++;						\
109	reg_entry++;							\
110})
111
112#define RTAS_FADUMP_CPU_ID_MASK			((1UL << 32) - 1)
113
114#endif /* _PSERIES_RTAS_FADUMP_H */
115