From 188cf8d96080f1c5ae37232d1595d5282ee0ff1d Mon Sep 17 00:00:00 2001 From: zwelch Date: Fri, 29 May 2009 04:00:51 +0000 Subject: [PATCH] Add documentation to flash.h: - provides low-level information about each flash API interface, - gives driver authors some documentation about the driver interface, - updated extensively from the original patch provided by Duane Ellis. git-svn-id: svn://svn.berlios.de/openocd/trunk@1942 b42882b7-edfa-0310-969c-e2dbd0fdcd60 --- src/flash/flash.h | 257 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 245 insertions(+), 12 deletions(-) diff --git a/src/flash/flash.h b/src/flash/flash.h index 1a98286c..26b3b118 100644 --- a/src/flash/flash.h +++ b/src/flash/flash.h @@ -33,65 +33,298 @@ struct image_s; #define FLASH_MAX_ERROR_STR (128) +/** + * Describes the geometry and status of a single flash sector + * within a flash bank. A single bank typically consists of multiple + * sectors, each of which can be erased and protected independently. + */ typedef struct flash_sector_s { + /// Bus offset from start of the flash chip (in bytes). u32 offset; + /// Number of bytes in this flash sector. u32 size; + /** + * Indication of erasure status: 0=not erased, 1=erased, + * other=unknown. Set by @c flash_driver_s::erase_check. + */ int is_erased; + /** + * Indication of protection status: 0=unprotected/unlocked, + * 1=protected/locked, other=unknown. Set by + * @c flash_driver_s::protect_check. + */ int is_protected; } flash_sector_t; struct flash_bank_s; +/** + * @brief Provides the implementation-independent structure that defines + * all of the callbacks required by OpenOCD flash drivers. + * + * Driver authors must implement the routines defined here, providing an + * instance with the fields filled out. After that, the instance must + * be registered in flash.c, so it can be used by the driver lookup system. + * + * Specifically, the user can issue the command: @par + * @code + * flash bank DRIVERNAME ...parameters... + * @endcode + * + * OpenOCD will search for the driver with a @c flash_driver_s::name + * that matches @c DRIVERNAME. + * + * The flash subsystem calls some of the other drivers routines a using + * corresponding static flash_driver_callback() + * routine in flash.c. + */ typedef struct flash_driver_s { + /** + * Gives a human-readable name of this flash driver, + * This field is used to select and initialize the driver. + */ char *name; + + /** + * Registers driver-specific commands. When called (during the + * "flash bank" command), the driver may register addition + * commands to support new flash chip functions. + * + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*register_commands)(struct command_context_s *cmd_ctx); + + /** + * Finish the "flash bank" command for @a bank. The + * @a bank parameter will have been filled in by the core flash + * layer when this routine is called, and the driver can store + * additional information in its flash_bank_t::driver_priv field. + * + * @param cmd_ctx - the command context + * @param cmd - the command, in this case 'flash' + * @param args - parameters, see below + * @param argc - number of parameters on command line + * @param bank - new filled in flash bank. + * + * The args are: @par + * @code + * args[0] = bank + * args[1] = drivername {name above} + * args[2] = baseaddress + * args[3] = lengthbytes + * args[4] = chip_width_in bytes + * args[5] = bus_width_bytes + * args[6] = driver-specific parameters + * @endcode + * + * For example, args[4] = 16 bit flash, args[5] = 32bit bus. + * + * If extra arguments are provided (@a argc > 6), they will + * start in @a args[6]. These can be used to implement + * driver-specific extensions. + * + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*flash_bank_command)(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc, struct flash_bank_s *bank); - /* use flash_driver_erase() wrapper to invoke */ + /** + * Bank/sector erase routine (target-specific). When + * called, the flash driver should erase the specified sectors + * using whatever means are at its disposal. + * + * @param bank The bank of flash to be erased. + * @param first The number of the first sector to erase, typically 0. + * @param last The number of the last sector to erase, typically N-1. + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*erase)(struct flash_bank_s *bank, int first, int last); - /* use flash_driver_protect() wrapper to invoke */ + /** + * Bank/sector protection routine (target-specific). + * When called, the driver should disable 'flash write' bits (or + * enable 'erase protection' bits) for the given @a bank and @a + * sectors. + * + * @param bank The bank to protect or unprotect. + * @param set If non-zero, enable protection; if 0, disable it. + * @param first The first sector to (un)protect, typicaly 0. + * @param last The last sector to (un)project, typically N-1. + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*protect)(struct flash_bank_s *bank, int set, int first, int last); - /* use the flash_driver_write() wrapper to invoke. */ + /** + * Program data into the flash. Note CPU address will be + * "bank->base + offset", while the physical address is + * dependent upon current target MMU mappings. + * + * @param bank The bank to program + * @param buffer The data bytes to write. + * @param offset The offset into the chip to program. + * @param count The number of bytes to write. + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*write)(struct flash_bank_s *bank, u8 *buffer, u32 offset, u32 count); + /** + * Probe to determine what kind of flash is present. + * This is invoked by the "probe" script command. + * + * @param bank The bank to probe + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*probe)(struct flash_bank_s *bank); + + /** + * Check the erasure status of a flash bank. + * When called, the driver routine must perform the required + * checks and then set the @c flash_sector_s::is_erased field + * for each of the flash banks's sectors. + * + * @param bank The bank to check + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*erase_check)(struct flash_bank_s *bank); + + /** + * Determine if the specific bank is "protected" or not. + * When called, the driver routine must must perform the + * required protection check(s) and then set the @c + * flash_sector_s::is_protected field for each of the flash + * bank's sectors. + * + * @param bank - the bank to check + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*protect_check)(struct flash_bank_s *bank); + + /** + * Display human-readable information about the flash + * bank into the given buffer. Drivers must be careful to avoid + * overflowing the buffer. + * + * @param bank - the bank to get info about + * @param char - where to put the text for the human to read + * @param buf_size - the size of the human buffer. + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*info)(struct flash_bank_s *bank, char *buf, int buf_size); + + /** + * A more gentle flavor of filash_driver_s::probe, performing + * setup with less noise. Generally, driver routines should test + * to seee if the bank has already been probed; if it has, the + * driver probably should not perform its probe a second time. + * + * This callback is often called from the inside of other + * routines (e.g. GDB flash downloads) to autoprobe the flash as + * it is programing the flash. + * + * @param bank - the bank to probe + * @returns ERROR_OK if successful; otherwise, an error code. + */ int (*auto_probe)(struct flash_bank_s *bank); } flash_driver_t; +/** + * Provides details of a flash bank, available either on-chip or through + * a major interface. + * + * This structure will be passed as a parameter to the callbacks in the + * flash_driver_s structure, some of which may modify the contents of + * this structure of the area of flash that it defines. Driver writers + * may use the @c driver_priv member to store additional data on a + * per-bank basis, if required. + */ typedef struct flash_bank_s { - struct target_s *target; - flash_driver_t *driver; - void *driver_priv; - int bank_number; - u32 base; - u32 size; - int chip_width; - int bus_width; + struct target_s *target; /**< Target to which this bank belongs. */ + + flash_driver_t *driver; /**< Driver for this bank. */ + void *driver_priv; /**< Private driver storage pointer */ + + int bank_number; /**< The 'bank' (or chip number) of this instance. */ + u32 base; /**< The base address of this bank */ + u32 size; /**< The size of this chip bank, in bytes */ + + int chip_width; /**< Width of the chip in bytes (1,2,4 bytes) */ + int bus_width; /**< Maximum bus width, in bytes (1,2,4 bytes) */ + + /** + * The number of sectors on this chip. This value will + * be set intially to 0, and the flash driver must set this to + * some non-zero value during "probe()" or "auto_probe()". + */ int num_sectors; + /// Array of sectors, allocated and initilized by the flash driver flash_sector_t *sectors; - struct flash_bank_s *next; + + struct flash_bank_s *next; /**< The next flash bank on this chip */ } flash_bank_t; +/// Registers the 'flash' subsystem commands extern int flash_register_commands(struct command_context_s *cmd_ctx); +/// Initializes the 'flash' subsystem drivers extern int flash_init_drivers(struct command_context_s *cmd_ctx); +/** + * Erases @a length bytes in the @a target flash, starting at @a addr. + * @returns ERROR_OK if successful; otherwise, an error code. + */ extern int flash_erase_address_range(struct target_s *target, u32 addr, u32 length); +/** + * Writes @a image into the @a target flash. The @a written parameter + * will contain the + * @param target The target with the flash to be programmed. + * @param image The image that will be programmed to flash. + * @param written On return, contains the number of bytes written. + * @param erase If non-zero, indicates the flash driver should first + * erase the corresponding banks or sectors before programming. + * @returns ERROR_OK if successful; otherwise, an error code. + */ extern int flash_write(struct target_s *target, struct image_s *image, u32 *written, int erase); +/** + * Forces targets to re-examine their erase/protection state. + * This routine must be called when the system may modify the status. + */ extern void flash_set_dirty(void); +/// @returns The number of flash banks currently defined. extern int flash_get_bank_count(void); +/** + * Provides default erased-bank check handling. Checks to see if + * the flash driver knows they are erased; if things look uncertain, + * this routine will call default_flash_mem_blank_check() to confirm. + * @returns ERROR_OK if successful; otherwise, an error code. + */ extern int default_flash_blank_check(struct flash_bank_s *bank); +/** + * Provides a default blank flash memory check. Ensures the contents + * of the given bank have truly been erased. + * @param bank The flash bank. + * @returns ERROR_OK if successful; otherwise, an error code. + */ extern int default_flash_mem_blank_check(struct flash_bank_s *bank); +/** + * Returns a flash bank by the specified flash_bank_s bank_number, @a num. + * @param num The flash bank number. + * @returns A flash_bank_t for flash bank @a num, or NULL + */ extern flash_bank_t *get_flash_bank_by_num(int num); +/** + * Returns the flash bank like get_flash_bank_by_num(), without probing. + * @param num The flash bank number. + * @returns A flash_bank_t for flash bank @a num, or NULL. + */ extern flash_bank_t *get_flash_bank_by_num_noprobe(int num); +/** + * Returns the flash bank located at a specified address. + * @param target The target, presumed to contain one or more banks. + * @param addr An address that is within the range of the bank. + * @returns The flash_bank_t located at @a addr, or NULL. + */ extern flash_bank_t *get_flash_bank_by_addr(struct target_s *target, u32 addr); #define ERROR_FLASH_BANK_INVALID (-900) -- 2.39.5