opal-fadump.h

  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 * in the capture kernel to process the crash dump.
 35 */
 36struct opal_fadump_mem_struct {
 37	u8	version;
 38	u8	reserved[3];
 39	__be16	region_cnt;		/* number of regions */
 40	__be16	registered_regions;	/* Regions registered for MPIPL */
 41	__be64	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 */
 58struct 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. */
 80struct hdat_fadump_reg_entry {
 81	__be32		reg_type;
 82	__be32		reg_num;
 83	__be64		reg_val;
 84} __packed;
 85
 86static 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
124static 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		       (u64 __force)(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 */