/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Firmware-Assisted Dump support on POWERVM platform.
 *
 * Copyright 2011, Mahesh Salgaonkar, IBM Corporation.
 * Copyright 2019, Hari Bathini, IBM Corporation.
 */

#ifndef _PSERIES_RTAS_FADUMP_H
#define _PSERIES_RTAS_FADUMP_H

/*
 * On some Power systems where RMO is 128MB, it still requires minimum of
 * 256MB for kernel to boot successfully. When kdump infrastructure is
 * configured to save vmcore over network, we run into OOM issue while
 * loading modules related to network setup. Hence we need additional 64M
 * of memory to avoid OOM issue.
 */
#define RTAS_FADUMP_MIN_BOOT_MEM        ((0x1UL << 28) + (0x1UL << 26))

/* Firmware provided dump sections */
#define RTAS_FADUMP_CPU_STATE_DATA      0x0001
#define RTAS_FADUMP_HPTE_REGION         0x0002
#define RTAS_FADUMP_REAL_MODE_REGION    0x0011

/* OS defined sections */
#define RTAS_FADUMP_PARAM_AREA          0x0100

/* Dump request flag */
#define RTAS_FADUMP_REQUEST_FLAG        0x00000001

/* Dump status flag */
#define RTAS_FADUMP_ERROR_FLAG          0x2000

/*
 * The Firmware Assisted Dump Memory structure supports a maximum of 10 sections
 * in the dump memory structure. Presently, three sections are used for
 * CPU state data, HPTE & Parameters area, while the remaining seven sections
 * can be used for boot memory regions.
 */
#define MAX_SECTIONS                            10
#define RTAS_FADUMP_MAX_BOOT_MEM_REGS           7

/* Kernel Dump section info */
struct rtas_fadump_section {
        __be32  request_flag;
        __be16  source_data_type;
        __be16  error_flags;
        __be64  source_address;
        __be64  source_len;
        __be64  bytes_dumped;
        __be64  destination_address;
};

/* ibm,configure-kernel-dump header. */
struct rtas_fadump_section_header {
        __be32  dump_format_version;
        __be16  dump_num_sections;
        __be16  dump_status_flag;
        __be32  offset_first_dump_section;

        /* Fields for disk dump option. */
        __be32  dd_block_size;
        __be64  dd_block_offset;
        __be64  dd_num_blocks;
        __be32  dd_offset_disk_path;

        /* Maximum time allowed to prevent an automatic dump-reboot. */
        __be32  max_time_auto;
};

/*
 * Firmware Assisted dump memory structure. This structure is required for
 * registering future kernel dump with power firmware through rtas call.
 *
 * In version 1, the platform permits one section header, dump-disk path
 * and ten sections.
 *
 * Note: No disk dump option. Hence disk dump path string section is not
 * included.
 */
struct rtas_fadump_mem_struct {
        struct rtas_fadump_section_header       header;
        struct rtas_fadump_section              rgn[MAX_SECTIONS];
};

/*
 * The firmware-assisted dump format.
 *
 * The register save area is an area in the partition's memory used to preserve
 * the register contents (CPU state data) for the active CPUs during a firmware
 * assisted dump. The dump format contains register save area header followed
 * by register entries. Each list of registers for a CPU starts with "CPUSTRT"
 * and ends with "CPUEND".
 */

/* Register save area header. */
struct rtas_fadump_reg_save_area_header {
        __be64          magic_number;
        __be32          version;
        __be32          num_cpu_offset;
};

/* Register entry. */
struct rtas_fadump_reg_entry {
        __be64          reg_id;
        __be64          reg_value;
};

/* Utility macros */
#define RTAS_FADUMP_SKIP_TO_NEXT_CPU(reg_entry)                         \
({                                                                      \
        while (be64_to_cpu(reg_entry->reg_id) !=                        \
               fadump_str_to_u64("CPUEND"))                             \
                reg_entry++;                                            \
        reg_entry++;                                                    \
})

#define RTAS_FADUMP_CPU_ID_MASK                 ((1UL << 32) - 1)

#endif /* _PSERIES_RTAS_FADUMP_H */