qemu/include/hw/nvram/fw_cfg.h

#ifndef FW_CFG_H
#define FW_CFG_H

#include "exec/hwaddr.h"
#include "standard-headers/linux/qemu_fw_cfg.h"
#include "hw/sysbus.h"
#include "sysemu/dma.h"
#include "qom/object.h"

#define TYPE_FW_CFG     "fw_cfg"
#define TYPE_FW_CFG_IO  "fw_cfg_io"
#define TYPE_FW_CFG_MEM "fw_cfg_mem"
#define TYPE_FW_CFG_DATA_GENERATOR_INTERFACE "fw_cfg-data-generator"

OBJECT_DECLARE_SIMPLE_TYPE(FWCfgState, FW_CFG)
OBJECT_DECLARE_SIMPLE_TYPE(FWCfgIoState, FW_CFG_IO)
OBJECT_DECLARE_SIMPLE_TYPE(FWCfgMemState, FW_CFG_MEM)

typedef struct FWCfgDataGeneratorClass FWCfgDataGeneratorClass;
DECLARE_CLASS_CHECKERS(FWCfgDataGeneratorClass, FW_CFG_DATA_GENERATOR,
                       TYPE_FW_CFG_DATA_GENERATOR_INTERFACE)

struct FWCfgDataGeneratorClass {
    /*< private >*/
    InterfaceClass parent_class;
    /*< public >*/

    /**
     * get_data:
     * @obj: the object implementing this interface
     * @errp: pointer to a NULL-initialized error object
     *
     * Returns: reference to a byte array containing the data on success,
     *          or NULL on error.
     *
     * The caller should release the reference when no longer
     * required.
     */
    GByteArray *(*get_data)(Object *obj, Error **errp);
};

typedef struct fw_cfg_file FWCfgFile;

#define FW_CFG_ORDER_OVERRIDE_VGA    70
#define FW_CFG_ORDER_OVERRIDE_NIC    80
#define FW_CFG_ORDER_OVERRIDE_USER   100
#define FW_CFG_ORDER_OVERRIDE_DEVICE 110

void fw_cfg_set_order_override(FWCfgState *fw_cfg, int order);
void fw_cfg_reset_order_override(FWCfgState *fw_cfg);

typedef struct FWCfgFiles {
    uint32_t  count;
    FWCfgFile f[];
} FWCfgFiles;

typedef struct fw_cfg_dma_access FWCfgDmaAccess;

typedef void (*FWCfgCallback)(void *opaque);
typedef void (*FWCfgWriteCallback)(void *opaque, off_t start, size_t len);

struct FWCfgState {
    /*< private >*/
    SysBusDevice parent_obj;
    /*< public >*/

    uint16_t file_slots;
    FWCfgEntry *entries[2];
    int *entry_order;
    FWCfgFiles *files;
    uint16_t cur_entry;
    uint32_t cur_offset;
    Notifier machine_ready;

    int fw_cfg_order_override;

    bool dma_enabled;
    dma_addr_t dma_addr;
    AddressSpace *dma_as;
    MemoryRegion dma_iomem;

    /* restore during migration */
    bool acpi_mr_restore;
    uint64_t table_mr_size;
    uint64_t linker_mr_size;
    uint64_t rsdp_mr_size;
};

struct FWCfgIoState {
    /*< private >*/
    FWCfgState parent_obj;
    /*< public >*/

    MemoryRegion comb_iomem;
};

struct FWCfgMemState {
    /*< private >*/
    FWCfgState parent_obj;
    /*< public >*/

    MemoryRegion ctl_iomem, data_iomem;
    uint32_t data_width;
    MemoryRegionOps wide_data_ops;
};

/**
 * fw_cfg_add_bytes:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @data: pointer to start of item data
 * @len: size of item data
 *
 * Add a new fw_cfg item, available by selecting the given key, as a raw
 * "blob" of the given size. The data referenced by the starting pointer
 * is only linked, NOT copied, into the data structure of the fw_cfg device.
 */
void fw_cfg_add_bytes(FWCfgState *s, uint16_t key, void *data, size_t len);

/**
 * fw_cfg_add_bytes_callback:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @select_cb: callback function when selecting
 * @write_cb: callback function after a write
 * @callback_opaque: argument to be passed into callback function
 * @data: pointer to start of item data
 * @len: size of item data
 * @read_only: is file read only
 *
 * Add a new fw_cfg item, available by selecting the given key, as a raw
 * "blob" of the given size. The data referenced by the starting pointer
 * is only linked, NOT copied, into the data structure of the fw_cfg device.
 */
void fw_cfg_add_bytes_callback(FWCfgState *s, uint16_t key,
                               FWCfgCallback select_cb,
                               FWCfgWriteCallback write_cb,
                               void *callback_opaque,
                               void *data, size_t len,
                               bool read_only);

/**
 * fw_cfg_add_string:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: NUL-terminated ascii string
 *
 * Add a new fw_cfg item, available by selecting the given key. The item
 * data will consist of a dynamically allocated copy of the provided string,
 * including its NUL terminator.
 */
void fw_cfg_add_string(FWCfgState *s, uint16_t key, const char *value);

/**
 * fw_cfg_modify_string:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: NUL-terminated ascii string
 *
 * Replace the fw_cfg item available by selecting the given key. The new
 * data will consist of a dynamically allocated copy of the provided string,
 * including its NUL terminator. The data being replaced, assumed to have
 * been dynamically allocated during an earlier call to either
 * fw_cfg_add_string() or fw_cfg_modify_string(), is freed before returning.
 */
void fw_cfg_modify_string(FWCfgState *s, uint16_t key, const char *value);

/**
 * fw_cfg_add_i16:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 16-bit integer
 *
 * Add a new fw_cfg item, available by selecting the given key. The item
 * data will consist of a dynamically allocated copy of the given 16-bit
 * value, converted to little-endian representation.
 */
void fw_cfg_add_i16(FWCfgState *s, uint16_t key, uint16_t value);

/**
 * fw_cfg_modify_i16:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 16-bit integer
 *
 * Replace the fw_cfg item available by selecting the given key. The new
 * data will consist of a dynamically allocated copy of the given 16-bit
 * value, converted to little-endian representation. The data being replaced,
 * assumed to have been dynamically allocated during an earlier call to
 * either fw_cfg_add_i16() or fw_cfg_modify_i16(), is freed before returning.
 */
void fw_cfg_modify_i16(FWCfgState *s, uint16_t key, uint16_t value);

/**
 * fw_cfg_add_i32:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 32-bit integer
 *
 * Add a new fw_cfg item, available by selecting the given key. The item
 * data will consist of a dynamically allocated copy of the given 32-bit
 * value, converted to little-endian representation.
 */
void fw_cfg_add_i32(FWCfgState *s, uint16_t key, uint32_t value);

/**
 * fw_cfg_modify_i32:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 32-bit integer
 *
 * Replace the fw_cfg item available by selecting the given key. The new
 * data will consist of a dynamically allocated copy of the given 32-bit
 * value, converted to little-endian representation. The data being replaced,
 * assumed to have been dynamically allocated during an earlier call to
 * either fw_cfg_add_i32() or fw_cfg_modify_i32(), is freed before returning.
 */
void fw_cfg_modify_i32(FWCfgState *s, uint16_t key, uint32_t value);

/**
 * fw_cfg_add_i64:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 64-bit integer
 *
 * Add a new fw_cfg item, available by selecting the given key. The item
 * data will consist of a dynamically allocated copy of the given 64-bit
 * value, converted to little-endian representation.
 */
void fw_cfg_add_i64(FWCfgState *s, uint16_t key, uint64_t value);

/**
 * fw_cfg_modify_i64:
 * @s: fw_cfg device being modified
 * @key: selector key value for new fw_cfg item
 * @value: 64-bit integer
 *
 * Replace the fw_cfg item available by selecting the given key. The new
 * data will consist of a dynamically allocated copy of the given 64-bit
 * value, converted to little-endian representation. The data being replaced,
 * assumed to have been dynamically allocated during an earlier call to
 * either fw_cfg_add_i64() or fw_cfg_modify_i64(), is freed before returning.
 */
void fw_cfg_modify_i64(FWCfgState *s, uint16_t key, uint64_t value);

/**
 * fw_cfg_add_file:
 * @s: fw_cfg device being modified
 * @filename: name of new fw_cfg file item
 * @data: pointer to start of item data
 * @len: size of item data
 *
 * Add a new NAMED fw_cfg item as a raw "blob" of the given size. The data
 * referenced by the starting pointer is only linked, NOT copied, into the
 * data structure of the fw_cfg device.
 * The next available (unused) selector key starting at FW_CFG_FILE_FIRST
 * will be used; also, a new entry will be added to the file directory
 * structure residing at key value FW_CFG_FILE_DIR, containing the item name,
 * data size, and assigned selector key value.
 */
void fw_cfg_add_file(FWCfgState *s, const char *filename, void *data,
                     size_t len);

/**
 * fw_cfg_add_file_callback:
 * @s: fw_cfg device being modified
 * @filename: name of new fw_cfg file item
 * @select_cb: callback function when selecting
 * @write_cb: callback function after a write
 * @callback_opaque: argument to be passed into callback function
 * @data: pointer to start of item data
 * @len: size of item data
 * @read_only: is file read only
 *
 * Add a new NAMED fw_cfg item as a raw "blob" of the given size. The data
 * referenced by the starting pointer is only linked, NOT copied, into the
 * data structure of the fw_cfg device.
 * The next available (unused) selector key starting at FW_CFG_FILE_FIRST
 * will be used; also, a new entry will be added to the file directory
 * structure residing at key value FW_CFG_FILE_DIR, containing the item name,
 * data size, and assigned selector key value.
 * Additionally, set a callback function (and argument) to be called each
 * time this item is selected (by having its selector key either written to
 * the fw_cfg control register, or passed to QEMU in FWCfgDmaAccess.control
 * with FW_CFG_DMA_CTL_SELECT).
 */
void fw_cfg_add_file_callback(FWCfgState *s, const char *filename,
                              FWCfgCallback select_cb,
                              FWCfgWriteCallback write_cb,
                              void *callback_opaque,
                              void *data, size_t len, bool read_only);

/**
 * fw_cfg_modify_file:
 * @s: fw_cfg device being modified
 * @filename: name of new fw_cfg file item
 * @data: pointer to start of item data
 * @len: size of item data
 *
 * Replace a NAMED fw_cfg item. If an existing item is found, its callback
 * information will be cleared, and a pointer to its data will be returned
 * to the caller, so that it may be freed if necessary. If an existing item
 * is not found, this call defaults to fw_cfg_add_file(), and NULL is
 * returned to the caller.
 * In either case, the new item data is only linked, NOT copied, into the
 * data structure of the fw_cfg device.
 *
 * Returns: pointer to old item's data, or NULL if old item does not exist.
 */
void *fw_cfg_modify_file(FWCfgState *s, const char *filename, void *data,
                         size_t len);

/**
 * fw_cfg_add_from_generator:
 * @s: fw_cfg device being modified
 * @filename: name of new fw_cfg file item
 * @gen_id: name of object implementing FW_CFG_DATA_GENERATOR interface
 * @errp: pointer to a NULL initialized error object
 *
 * Add a new NAMED fw_cfg item with the content generated from the
 * @gen_id object. The data generated by the @gen_id object is copied
 * into the data structure of the fw_cfg device.
 * The next available (unused) selector key starting at FW_CFG_FILE_FIRST
 * will be used; also, a new entry will be added to the file directory
 * structure residing at key value FW_CFG_FILE_DIR, containing the item name,
 * data size, and assigned selector key value.
 *
 * Returns: %true on success, %false on error.
 */
bool fw_cfg_add_from_generator(FWCfgState *s, const char *filename,
                               const char *gen_id, Error **errp);

/**
 * fw_cfg_add_extra_pci_roots:
 * @bus: main pci root bus to be scanned from
 * @s: fw_cfg device being modified
 *
 * Add a new fw_cfg item...
 */
void fw_cfg_add_extra_pci_roots(PCIBus *bus, FWCfgState *s);

FWCfgState *fw_cfg_init_io_dma(uint32_t iobase, uint32_t dma_iobase,
                                AddressSpace *dma_as);
FWCfgState *fw_cfg_init_io(uint32_t iobase);
FWCfgState *fw_cfg_init_mem(hwaddr ctl_addr, hwaddr data_addr);
FWCfgState *fw_cfg_init_mem_wide(hwaddr ctl_addr,
                                 hwaddr data_addr, uint32_t data_width,
                                 hwaddr dma_addr, AddressSpace *dma_as);

FWCfgState *fw_cfg_find(void);
bool fw_cfg_dma_enabled(void *opaque);

/**
 * fw_cfg_arch_key_name:
 *
 * @key: The uint16 selector key.
 *
 * The key is architecture-specific (the FW_CFG_ARCH_LOCAL mask is expected
 * to be set in the key).
 *
 * Returns: The stringified architecture-specific name if the selector
 *          refers to a well-known numerically defined item, or NULL on
 *          key lookup failure.
 */
const char *fw_cfg_arch_key_name(uint16_t key);

/**
 * load_image_to_fw_cfg() - Load an image file into an fw_cfg entry identified
 *                          by key.
 * @fw_cfg:         The firmware config instance to store the data in.
 * @size_key:       The firmware config key to store the size of the loaded
 *                  data under, with fw_cfg_add_i32().
 * @data_key:       The firmware config key to store the loaded data under,
 *                  with fw_cfg_add_bytes().
 * @image_name:     The name of the image file to load. If it is NULL, the
 *                  function returns without doing anything.
 * @try_decompress: Whether the image should be decompressed (gunzipped) before
 *                  adding it to fw_cfg. If decompression fails, the image is
 *                  loaded as-is.
 *
 * In case of failure, the function prints an error message to stderr and the
 * process exits with status 1.
 */
void load_image_to_fw_cfg(FWCfgState *fw_cfg, uint16_t size_key,
                          uint16_t data_key, const char *image_name,
                          bool try_decompress);

#endif