linux/arch/powerpc/platforms/powernv/opal-fadump.h
Hari Bathini b74196af37 powerpc/fadump: Fix fadump to work with a different endian capture kernel
Dump capture would fail if capture kernel is not of the endianess as the
production kernel, because the in-memory data structure (struct
opal_fadump_mem_struct) shared across production kernel and capture
kernel assumes the same endianess for both the kernels, which doesn't
have to be true always. Fix it by having a well-defined endianess for
struct opal_fadump_mem_struct.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161902744901.86147.14719228311655123526.stgit@hbathini
2022-04-26 22:35:46 +10:00

147 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Firmware-Assisted Dump support on POWER platform (OPAL).
*
* Copyright 2019, Hari Bathini, IBM Corporation.
*/
#ifndef _POWERNV_OPAL_FADUMP_H
#define _POWERNV_OPAL_FADUMP_H
#include <asm/reg.h>
/*
* With kernel & initrd loaded at 512MB (with 256MB size), enforce a minimum
* boot memory size of 768MB to ensure f/w loading kernel and initrd doesn't
* mess with crash'ed kernel's memory during MPIPL.
*/
#define OPAL_FADUMP_MIN_BOOT_MEM (0x30000000UL)
/*
* OPAL FADump metadata structure format version
*
* OPAL FADump kernel metadata structure stores kernel metadata needed to
* register-for/process crash dump. Format version is used to keep a tab on
* the changes in the structure format. The changes, if any, to the format
* are expected to be minimal and backward compatible.
*/
#define OPAL_FADUMP_VERSION 0x1
/*
* OPAL FADump kernel metadata
*
* The address of this structure will be registered with f/w for retrieving
* in the capture kernel to process the crash dump.
*/
struct opal_fadump_mem_struct {
u8 version;
u8 reserved[3];
__be16 region_cnt; /* number of regions */
__be16 registered_regions; /* Regions registered for MPIPL */
__be64 fadumphdr_addr;
struct opal_mpipl_region rgn[FADUMP_MAX_MEM_REGS];
} __packed;
/*
* CPU state data
*
* CPU state data information is provided by f/w. The format for this data
* is defined in the HDAT spec. Version is used to keep a tab on the changes
* in this CPU state data format. Changes to this format are unlikely, but
* if there are any changes, please refer to latest HDAT specification.
*/
#define HDAT_FADUMP_CPU_DATA_VER 1
#define HDAT_FADUMP_CORE_INACTIVE (0x0F)
/* HDAT thread header for register entries */
struct hdat_fadump_thread_hdr {
__be32 pir;
/* 0x00 - 0x0F - The corresponding stop state of the core */
u8 core_state;
u8 reserved[3];
__be32 offset; /* Offset to Register Entries array */
__be32 ecnt; /* Number of entries */
__be32 esize; /* Alloc size of each array entry in bytes */
__be32 eactsz; /* Actual size of each array entry in bytes */
} __packed;
/* Register types populated by f/w */
#define HDAT_FADUMP_REG_TYPE_GPR 0x01
#define HDAT_FADUMP_REG_TYPE_SPR 0x02
/* ID numbers used by f/w while populating certain registers */
#define HDAT_FADUMP_REG_ID_NIP 0x7D0
#define HDAT_FADUMP_REG_ID_MSR 0x7D1
#define HDAT_FADUMP_REG_ID_CCR 0x7D2
/* HDAT register entry. */
struct hdat_fadump_reg_entry {
__be32 reg_type;
__be32 reg_num;
__be64 reg_val;
} __packed;
static inline void opal_fadump_set_regval_regnum(struct pt_regs *regs,
u32 reg_type, u32 reg_num,
u64 reg_val)
{
if (reg_type == HDAT_FADUMP_REG_TYPE_GPR) {
if (reg_num < 32)
regs->gpr[reg_num] = reg_val;
return;
}
switch (reg_num) {
case SPRN_CTR:
regs->ctr = reg_val;
break;
case SPRN_LR:
regs->link = reg_val;
break;
case SPRN_XER:
regs->xer = reg_val;
break;
case SPRN_DAR:
regs->dar = reg_val;
break;
case SPRN_DSISR:
regs->dsisr = reg_val;
break;
case HDAT_FADUMP_REG_ID_NIP:
regs->nip = reg_val;
break;
case HDAT_FADUMP_REG_ID_MSR:
regs->msr = reg_val;
break;
case HDAT_FADUMP_REG_ID_CCR:
regs->ccr = reg_val;
break;
}
}
static inline void opal_fadump_read_regs(char *bufp, unsigned int regs_cnt,
unsigned int reg_entry_size,
bool cpu_endian,
struct pt_regs *regs)
{
struct hdat_fadump_reg_entry *reg_entry;
u64 val;
int i;
memset(regs, 0, sizeof(struct pt_regs));
for (i = 0; i < regs_cnt; i++, bufp += reg_entry_size) {
reg_entry = (struct hdat_fadump_reg_entry *)bufp;
val = (cpu_endian ? be64_to_cpu(reg_entry->reg_val) :
(u64)(reg_entry->reg_val));
opal_fadump_set_regval_regnum(regs,
be32_to_cpu(reg_entry->reg_type),
be32_to_cpu(reg_entry->reg_num),
val);
}
}
#endif /* _POWERNV_OPAL_FADUMP_H */