/**
 * @file    firmware_map.h
 * @brief   Flash memory map definition for Donghui OTA project
 *
 * Memory map (STM32G474RET6 - 512KB Flash, 128KB RAM):
 *
 * +-----------------------+ 0x08000000
 * | Bootloader            | 28KB
 * | - Vector table        |
 * | - Crypto context      |
 * | - SPI Flash driver    |
 * +-----------------------+ 0x08007000
 * | Parameter Sector      | 4KB
 * | - Boot flags          |
 * | - Version info        |
 * | - Upgrade status      |
 * +-----------------------+ 0x08008000
 * | App A (Active Bank)   | 240KB
 * +-----------------------+ 0x08044000
 * | App B (Backup Bank)   | 240KB
 * +-----------------------+ 0x08080000 (End of Flash)
 *
 * External SPI Flash (W25Q64 - 8MB):
 * +-----------------------+ 0x00000000
 * | OTA Download Buffer   | 1MB (for incoming encrypted firmware)
 * | (Multiple versions)   |
 * +-----------------------+ 0x00100000
 * | Factory Backup        | 512KB (golden firmware copy)
 * +-----------------------+ 0x00180000
 * | Log / Config Data     | 512KB
 * +-----------------------+ 0x00200000
 * | Reserved              | 6MB
 * +-----------------------+ 0x00800000 (End)
 */

#ifndef _FIRMWARE_MAP_H_
#define _FIRMWARE_MAP_H_

#include <stdint.h>

/* ========== Internal Flash Map ========== */

#define FLASH_BASE_ADDR         0x08000000UL
#define FLASH_TOTAL_SIZE        (512 * 1024)    /* 512KB */

/* Bootloader region */
#define BOOTLOADER_ADDR         0x08000000UL
#define BOOTLOADER_SIZE         (28 * 1024)     /* 28KB */
#define BOOTLOADER_SECTORS      7               /* 4KB per sector */

/* Parameter / Flag sector */
#define PARAM_SECTOR_ADDR       0x08007000UL
#define PARAM_SECTOR_SIZE       (4 * 1024)      /* 4KB, single sector */

/* App A (active bank) */
#define APP_A_ADDR              0x08008000UL
#define APP_A_SIZE              (240 * 1024)    /* 240KB */
#define APP_A_SECTORS           60

/* App B (backup bank) */
#define APP_B_ADDR              0x08044000UL
#define APP_B_SIZE              (240 * 1024)    /* 240KB */
#define APP_B_SECTORS           60

/* ========== External SPI Flash Map (W25Q64) ========== */

#define SPI_FLASH_TOTAL_SIZE    (8 * 1024 * 1024)   /* 8MB */

#define OTA_BUF_ADDR            0x00000000UL
#define OTA_BUF_SIZE            (1 * 1024 * 1024)   /* 1MB */

#define FACTORY_BACKUP_ADDR     0x00100000UL
#define FACTORY_BACKUP_SIZE     (512 * 1024)        /* 512KB */

#define LOG_CFG_ADDR            0x00180000UL
#define LOG_CFG_SIZE            (512 * 1024)        /* 512KB */

/* ========== Parameter Sector Structure ========== */

/* Stored at PARAM_SECTOR_ADDR in internal flash */
typedef struct __attribute__((packed)) {
    /* Boot configuration */
    uint32_t magic;                 /* 0xA5A5A5A5 for valid sector */
    uint32_t active_bank;           /* 0 = App A, 1 = App B */
    uint32_t upgrade_status;        /* See UPGRADE_STATUS_* */
    uint32_t boot_count;            /* Number of boots (for health check) */

    /* Firmware version info */
    uint32_t app_a_version;         /* Version code (e.g. 0x0201 = v2.1) */
    uint32_t app_b_version;
    uint32_t app_a_crc32;           /* CRC32 of App A firmware */
    uint32_t app_b_crc32;           /* CRC32 of App B firmware */

    /* OTA state */
    uint32_t ota_file_size;         /* Total size of OTA file in SPI flash */
    uint32_t ota_file_crc32;        /* CRC32 of OTA file content */
    uint32_t ota_downloaded;        /* 1 = fully downloaded, 0 = incomplete */
    uint32_t reserve[8];            /* Future use */

    /* End marker */
    uint32_t tail_magic;            /* 0x5A5A5A5A */
} BootParam_t;

/* ========== Upgrade Status Definitions ========== */

#define UPGRADE_STATUS_IDLE         0
#define UPGRADE_STATUS_DOWNLOADING  1
#define UPGRADE_STATUS_DOWNLOADED   2
#define UPGRADE_STATUS_VERIFIED     3
#define UPGRADE_STATUS_FLASHING     4
#define UPGRADE_STATUS_DONE         5
#define UPGRADE_STATUS_FAILED       0xFFFFFFFF

/* ========== Bootloader Version ========== */

#define BOOTLOADER_VERSION_MAJOR    1
#define BOOTLOADER_VERSION_MINOR    0
#define BOOTLOADER_VERSION_PATCH    0

#define BOOTLOADER_VERSION_HEX \
    ((BOOTLOADER_VERSION_MAJOR << 16) | \
     (BOOTLOADER_VERSION_MINOR << 8)  | \
     (BOOTLOADER_VERSION_PATCH))

/* ========== OTA Protocol Constants ========== */

#define OTA_PACKET_MAX_DATA        256     /* Max payload bytes per packet */
#define OTA_HEADER_SIZE            10      /* Sync(2) + Len(2) + Seq(2) + Type(2) + CRC16(2) */

#define OTA_TYPE_HELLO             0x0001  /* Handshake request */
#define OTA_TYPE_HELLO_ACK         0x0002  /* Handshake response */
#define OTA_TYPE_DATA              0x0010  /* Firmware data packet */
#define OTA_TYPE_DATA_ACK          0x0011  /* Data ACK */
#define OTA_TYPE_END               0x00FF  /* Transfer complete */
#define OTA_TYPE_ABORT             0x00FE  /* Abort transfer */

/* ========== Flash Protection ========== */

#define FLASH_OPT_RDP_LEVEL0       0xAA    /* No read protection */
#define FLASH_OPT_RDP_LEVEL1       0xBB    /* Read protection Level 1 */
#define FLASH_OPT_RDP_LEVEL2       0xCC    /* Read protection Level 2 (permanent) */

#endif /* _FIRMWARE_MAP_H_ */