/*
 * Firmware Assisted dump header file.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright 2011 IBM Corporation
 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
 */

#ifndef __PPC64_FA_DUMP_H__
#define __PPC64_FA_DUMP_H__

#ifdef CONFIG_FA_DUMP

/*
 * The RMA region will be saved for later dumping when kernel crashes.
 * RMA is Real Mode Area, the first block of logical memory address owned
 * by logical partition, containing the storage that may be accessed with
 * translate off.
 */
#define RMA_START       0x0
#define RMA_END         (ppc64_rma_size)

/*
 * 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 aditional 64M
 * of memory to avoid OOM issue.
 */
#define MIN_BOOT_MEM    (((RMA_END < (0x1UL << 28)) ? (0x1UL << 28) : RMA_END) \
                        + (0x1UL << 26))

#define memblock_num_regions(memblock_type)     (memblock.memblock_type.cnt)

#ifndef ELF_CORE_EFLAGS
#define ELF_CORE_EFLAGS 0
#endif

/* Firmware provided dump sections */
#define FADUMP_CPU_STATE_DATA   0x0001
#define FADUMP_HPTE_REGION      0x0002
#define FADUMP_REAL_MODE_REGION 0x0011

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

/* FAD commands */
#define FADUMP_REGISTER         1
#define FADUMP_UNREGISTER       2
#define FADUMP_INVALIDATE       3

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

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

#define CPU_UNKNOWN             (~((u32)0))

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

/* Kernel Dump section info */
struct fadump_section {
        u32     request_flag;
        u16     source_data_type;
        u16     error_flags;
        u64     source_address;
        u64     source_len;
        u64     bytes_dumped;
        u64     destination_address;
};

/* ibm,configure-kernel-dump header. */
struct fadump_section_header {
        u32     dump_format_version;
        u16     dump_num_sections;
        u16     dump_status_flag;
        u32     offset_first_dump_section;

        /* Fields for disk dump option. */
        u32     dd_block_size;
        u64     dd_block_offset;
        u64     dd_num_blocks;
        u32     dd_offset_disk_path;

        /* Maximum time allowed to prevent an automatic dump-reboot. */
        u32     max_time_auto;
};

/*
 * Firmware Assisted dump memory structure. This structure is required for
 * registering future kernel dump with power firmware through rtas call.
 *
 * No disk dump option. Hence disk dump path string section is not included.
 */
struct fadump_mem_struct {
        struct fadump_section_header    header;

        /* Kernel dump sections */
        struct fadump_section           cpu_state_data;
        struct fadump_section           hpte_region;
        struct fadump_section           rmr_region;
};

/* Firmware-assisted dump configuration details. */
struct fw_dump {
        unsigned long   cpu_state_data_size;
        unsigned long   hpte_region_size;
        unsigned long   boot_memory_size;
        unsigned long   reserve_dump_area_start;
        unsigned long   reserve_dump_area_size;
        /* cmd line option during boot */
        unsigned long   reserve_bootvar;

        unsigned long   fadumphdr_addr;
        unsigned long   cpu_notes_buf;
        unsigned long   cpu_notes_buf_size;

        int             ibm_configure_kernel_dump;

        unsigned long   fadump_enabled:1;
        unsigned long   fadump_supported:1;
        unsigned long   dump_active:1;
        unsigned long   dump_registered:1;
};

/*
 * Copy the ascii values for first 8 characters from a string into u64
 * variable at their respective indexes.
 * e.g.
 *  The string "FADMPINF" will be converted into 0x4641444d50494e46
 */
static inline u64 str_to_u64(const char *str)
{
        u64 val = 0;
        int i;

        for (i = 0; i < sizeof(val); i++)
                val = (*str) ? (val << 8) | *str++ : val << 8;
        return val;
}
#define STR_TO_HEX(x)   str_to_u64(x)
#define REG_ID(x)       str_to_u64(x)

#define FADUMP_CRASH_INFO_MAGIC         STR_TO_HEX("FADMPINF")
#define REGSAVE_AREA_MAGIC              STR_TO_HEX("REGSAVE")

/* 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 fadump_reg_save_area_header {
        u64             magic_number;
        u32             version;
        u32             num_cpu_offset;
};

/* Register entry. */
struct fadump_reg_entry {
        u64             reg_id;
        u64             reg_value;
};

/* fadump crash info structure */
struct fadump_crash_info_header {
        u64             magic_number;
        u64             elfcorehdr_addr;
        u32             crashing_cpu;
        struct pt_regs  regs;
        struct cpumask  cpu_online_mask;
};

/* Crash memory ranges */
#define INIT_CRASHMEM_RANGES    (INIT_MEMBLOCK_REGIONS + 2)

struct fad_crash_memory_ranges {
        unsigned long long      base;
        unsigned long long      size;
};

extern int early_init_dt_scan_fw_dump(unsigned long node,
                const char *uname, int depth, void *data);
extern int fadump_reserve_mem(void);
extern int setup_fadump(void);
extern int is_fadump_active(void);
extern void crash_fadump(struct pt_regs *, const char *);
extern void fadump_cleanup(void);

#else   /* CONFIG_FA_DUMP */
static inline int is_fadump_active(void) { return 0; }
static inline void crash_fadump(struct pt_regs *regs, const char *str) { }
#endif
#endif