Driver_Storage.h

00001 
00002 /** \addtogroup hal */
00003 /** @{*/
00004 /*
00005  * Copyright (c) 2006-2016, ARM Limited, All Rights Reserved
00006  * SPDX-License-Identifier: Apache-2.0
00007  *
00008  * Licensed under the Apache License, Version 2.0 (the "License"); you may
00009  * not use this file except in compliance with the License.
00010  * You may obtain a copy of the License at
00011  *
00012  * http://www.apache.org/licenses/LICENSE-2.0
00013  *
00014  * Unless required by applicable law or agreed to in writing, software
00015  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00016  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00017  * See the License for the specific language governing permissions and
00018  * limitations under the License.
00019  */
00020 
00021 #ifndef __DRIVER_STORAGE_H
00022 #define __DRIVER_STORAGE_H
00023 
00024 #include <stdint.h>
00025 
00026 #ifdef __cplusplus
00027 extern "C" {
00028 #endif // __cplusplus
00029 
00030 #include "Driver_Common.h"
00031 
00032 #define ARM_STORAGE_API_VERSION ARM_DRIVER_VERSION_MAJOR_MINOR(1,00)  /* API version */
00033 
00034 
00035 #define _ARM_Driver_Storage_(n)      Driver_Storage##n
00036 #define  ARM_Driver_Storage_(n) _ARM_Driver_Storage_(n)
00037 
00038 #define ARM_STORAGE_INVALID_OFFSET  (0xFFFFFFFFFFFFFFFFULL) ///< Invalid address (relative to a storage controller's
00039                                                             ///< address space). A storage block may never start at this address.
00040 
00041 #define ARM_STORAGE_INVALID_ADDRESS (0xFFFFFFFFUL)          ///< Invalid address within the processor's memory address space.
00042                                                             ///< Refer to memory-mapped storage, i.e. < \ref ARM_DRIVER_STORAGE::ResolveAddress().
00043 
00044 /****** Storage specific error codes *****/
00045 #define ARM_STORAGE_ERROR_NOT_ERASABLE      (ARM_DRIVER_ERROR_SPECIFIC - 1) ///< Part (or all) of the range provided to Erase() isn't erasable.
00046 #define ARM_STORAGE_ERROR_NOT_PROGRAMMABLE  (ARM_DRIVER_ERROR_SPECIFIC - 2) ///< Part (or all) of the range provided to ProgramData() isn't programmable.
00047 #define ARM_STORAGE_ERROR_PROTECTED         (ARM_DRIVER_ERROR_SPECIFIC - 3) ///< Part (or all) of the range to Erase() or ProgramData() is protected.
00048 #define ARM_STORAGE_ERROR_RUNTIME_OR_INTEGRITY_FAILURE (ARM_DRIVER_ERROR_SPECIFIC - 4) ///< Runtime or sanity-check failure.
00049 
00050 /**
00051  * \brief Attributes of the storage range within a storage block.
00052  */
00053 typedef struct _ARM_STORAGE_BLOCK_ATTRIBUTES {
00054   uint32_t erasable      :  1;   ///< Erasing blocks is permitted with a minimum granularity of 'erase_unit'.
00055                                  ///<   @note: if 'erasable' is 0--i.e. the 'erase' operation isn't available--then
00056                                  ///<   'erase_unit' (see below) is immaterial and should be 0.
00057   uint32_t programmable  :  1;   ///< Writing to ranges is permitted with a minimum granularity of 'program_unit'.
00058                                  ///<   Writes are typically achieved through the ProgramData operation (following an erase);
00059                                  ///<   if storage isn't erasable (see 'erasable' above) but is memory-mapped
00060                                  ///<   (i.e. 'memory_mapped'), it can be written directly using memory-store operations.
00061   uint32_t executable    :  1;   ///< This storage block can hold program data; the processor can fetch and execute code
00062                                  ///<   sourced from it. Often this is accompanied with the device being 'memory_mapped' (see \ref ARM_STORAGE_INFO).
00063   uint32_t protectable   :  1;   ///< The entire block can be protected from program and erase operations. Once protection
00064                                  ///<   is enabled for a block, its 'erasable' and 'programmable' bits are turned off.
00065   uint32_t reserved      : 28;
00066   uint32_t erase_unit;           ///< Minimum erase size in bytes.
00067                                  ///<   The offset of the start of the erase-range should also be aligned with this value.
00068                                  ///<   Applicable if the 'erasable' attribute is set for the block.
00069                                  ///<   @note: if 'erasable' (see above) is 0--i.e. the 'erase' operation isn't available--then
00070                                  ///<   'erase_unit' is immaterial and should be 0.
00071   uint32_t protection_unit;      ///< Minimum protectable size in bytes. Applicable if the 'protectable'
00072                                  ///<   attribute is set for the block. This should be a divisor of the block's size. A
00073                                  ///<   block can be considered to be made up of consecutive, individually-protectable fragments.
00074 } ARM_STORAGE_BLOCK_ATTRIBUTES;
00075 
00076 /**
00077  * \brief A storage block is a range of memory with uniform attributes. Storage blocks
00078  * combine to make up the address map of a storage controller.
00079  */
00080 typedef struct _ARM_STORAGE_BLOCK {
00081   uint64_t                     addr;       ///< This is the start address of the storage block. It is
00082                                            ///<   expressed as an offset from the start of the storage map
00083                                            ///<   maintained by the owning storage controller.
00084   uint64_t                     size;       ///< This is the size of the storage block, in units of bytes.
00085                                            ///<   Together with addr, it describes a range [addr, addr+size).
00086   ARM_STORAGE_BLOCK_ATTRIBUTES attributes; ///< Attributes for this block.
00087 } ARM_STORAGE_BLOCK;
00088 
00089 /**
00090  * The check for a valid ARM_STORAGE_BLOCK.
00091  */
00092 #define ARM_STORAGE_VALID_BLOCK(BLK) (((BLK)->addr != ARM_STORAGE_INVALID_OFFSET) && ((BLK)->size != 0))
00093 
00094 /**
00095  * \brief Values for encoding storage memory-types with respect to programmability.
00096  *
00097  * Please ensure that the maximum of the following memory types doesn't exceed 16; we
00098  * encode this in a 4-bit field within ARM_STORAGE_INFO::programmability.
00099  */
00100 #define ARM_STORAGE_PROGRAMMABILITY_RAM       (0x0)
00101 #define ARM_STORAGE_PROGRAMMABILITY_ROM       (0x1) ///< Read-only memory.
00102 #define ARM_STORAGE_PROGRAMMABILITY_WORM      (0x2) ///< write-once-read-only-memory (WORM).
00103 #define ARM_STORAGE_PROGRAMMABILITY_ERASABLE  (0x3) ///< re-programmable based on erase. Supports multiple writes.
00104 
00105 /**
00106  * Values for encoding data-retention levels for storage blocks.
00107  *
00108  * Please ensure that the maximum of the following retention types doesn't exceed 16; we
00109  * encode this in a 4-bit field within ARM_STORAGE_INFO::retention_level.
00110  */
00111 #define ARM_RETENTION_WHILE_DEVICE_ACTIVE     (0x0) ///< Data is retained only during device activity.
00112 #define ARM_RETENTION_ACROSS_SLEEP            (0x1) ///< Data is retained across processor sleep.
00113 #define ARM_RETENTION_ACROSS_DEEP_SLEEP       (0x2) ///< Data is retained across processor deep-sleep.
00114 #define ARM_RETENTION_BATTERY_BACKED          (0x3) ///< Data is battery-backed. Device can be powered off.
00115 #define ARM_RETENTION_NVM                     (0x4) ///< Data is retained in non-volatile memory.
00116 
00117 /**
00118  * Device Data Security Protection Features. Applicable mostly to EXTERNAL_NVM.
00119  */
00120 typedef struct _ARM_STORAGE_SECURITY_FEATURES {
00121   uint32_t acls                :  1; ///< Protection against internal software attacks using ACLs.
00122   uint32_t rollback_protection :  1; ///< Roll-back protection. Set to true if the creator of the storage
00123                                      ///<   can ensure that an external attacker can't force an
00124                                      ///<   older firmware to run or to revert back to a previous state.
00125   uint32_t tamper_proof        :  1; ///< Tamper-proof memory (will be deleted on tamper-attempts using board level or chip level sensors).
00126   uint32_t internal_flash      :  1; ///< Internal flash.
00127   uint32_t reserved1           : 12;
00128 
00129   /**
00130    * Encode support for hardening against various classes of attacks.
00131    */
00132   uint32_t software_attacks     :  1; ///< device software (malware running on the device).
00133   uint32_t board_level_attacks  :  1; ///< board level attacks (debug probes, copy protection fuses.)
00134   uint32_t chip_level_attacks   :  1; ///< chip level attacks (tamper-protection).
00135   uint32_t side_channel_attacks :  1; ///< side channel attacks.
00136   uint32_t reserved2            : 12;
00137 } ARM_STORAGE_SECURITY_FEATURES;
00138 
00139 #define ARM_STORAGE_PROGRAM_CYCLES_INFINITE (0UL) /**< Infinite or unknown endurance for reprogramming. */
00140 
00141 /**
00142  * \brief Storage information. This contains device-metadata. It is the return
00143  *     value from calling GetInfo() on the storage driver.
00144  *
00145  * \details These fields serve a different purpose than the ones contained in
00146  *     \ref ARM_STORAGE_CAPABILITIES, which is another structure containing
00147  *     device-level metadata. ARM_STORAGE_CAPABILITIES describes the API
00148  *     capabilities, whereas ARM_STORAGE_INFO describes the device. Furthermore
00149  *     ARM_STORAGE_CAPABILITIES fits within a single word, and is designed to be
00150  *     passed around by value; ARM_STORAGE_INFO, on the other hand, contains
00151  *     metadata which doesn't fit into a single word and requires the use of
00152  *     pointers to be moved around.
00153  */
00154 typedef struct _ARM_STORAGE_INFO {
00155   uint64_t                      total_storage;        ///< Total available storage, in bytes.
00156   uint32_t                      program_unit;         ///< Minimum programming size in bytes.
00157                                                       ///<   The offset of the start of the program-range should also be aligned with this value.
00158                                                       ///<   Applicable only if the 'programmable' attribute is set for a block.
00159                                                       ///<   @note: setting program_unit to 0 has the effect of disabling the size and alignment
00160                                                       ///<   restrictions (setting it to 1 also has the same effect).
00161   uint32_t                      optimal_program_unit; ///< Optimal programming page-size in bytes. Some storage controllers
00162                                                       ///<   have internal buffers into which to receive data. Writing in chunks of
00163                                                       ///<   'optimal_program_unit' would achieve maximum programming speed.
00164                                                       ///<   Applicable only if the 'programmable' attribute is set for the underlying block(s).
00165   uint32_t                      program_cycles;       ///< A measure of endurance for reprogramming.
00166                                                       ///<   Use ARM_STORAGE_PROGRAM_CYCLES_INFINITE for infinite or unknown endurance.
00167   uint32_t                      erased_value    :  1; ///< Contents of erased memory (usually 1 to indicate erased bytes with state 0xFF).
00168   uint32_t                      memory_mapped   :  1; ///< This storage device has a mapping onto the processor's memory address space.
00169                                                       ///<   @note: For a memory-mapped block which isn't erasable but is programmable (i.e. if
00170                                                       ///<   'erasable' is set to 0, but 'programmable' is 1), writes should be possible directly to
00171                                                       ///<   the memory-mapped storage without going through the ProgramData operation.
00172   uint32_t                      programmability :  4; ///< A value to indicate storage programmability.
00173   uint32_t                      retention_level :  4;
00174   uint32_t                      reserved        : 22;
00175   ARM_STORAGE_SECURITY_FEATURES security;             ///< \ref ARM_STORAGE_SECURITY_FEATURES
00176 } ARM_STORAGE_INFO;
00177 
00178 /**
00179 \brief Operating status of the storage controller.
00180 */
00181 typedef struct _ARM_STORAGE_STATUS {
00182   uint32_t busy  : 1;                   ///< Controller busy flag
00183   uint32_t error : 1;                   ///< Read/Program/Erase error flag (cleared on start of next operation)
00184 } ARM_STORAGE_STATUS;
00185 
00186 /**
00187  * \brief Storage Driver API Capabilities.
00188  *
00189  * This data structure is designed to fit within a single word so that it can be
00190  * fetched cheaply using a call to driver->GetCapabilities().
00191  */
00192 typedef struct _ARM_STORAGE_CAPABILITIES {
00193   uint32_t asynchronous_ops :  1; ///< Used to indicate if APIs like initialize,
00194                                   ///<   read, erase, program, etc. can operate in asynchronous mode.
00195                                   ///<   Setting this bit to 1 means that the driver is capable
00196                                   ///<   of launching asynchronous operations; command completion is
00197                                   ///<   signaled by the invocation of a completion callback. If
00198                                   ///<   set to 1, drivers may still complete asynchronous
00199                                   ///<   operations synchronously as necessary--in which case they
00200                                   ///<   return a positive error code to indicate synchronous completion.
00201   uint32_t erase_all        :  1; ///< Supports EraseAll operation.
00202   uint32_t reserved         : 30;
00203 } ARM_STORAGE_CAPABILITIES;
00204 
00205 /**
00206  * Command opcodes for Storage. Completion callbacks use these codes to refer to
00207  * completing commands. Refer to \ref ARM_Storage_Callback_t.
00208  */
00209 typedef enum _ARM_STORAGE_OPERATION {
00210   ARM_STORAGE_OPERATION_GET_VERSION,
00211   ARM_STORAGE_OPERATION_GET_CAPABILITIES,
00212   ARM_STORAGE_OPERATION_INITIALIZE,
00213   ARM_STORAGE_OPERATION_UNINITIALIZE,
00214   ARM_STORAGE_OPERATION_POWER_CONTROL,
00215   ARM_STORAGE_OPERATION_READ_DATA,
00216   ARM_STORAGE_OPERATION_PROGRAM_DATA,
00217   ARM_STORAGE_OPERATION_ERASE,
00218   ARM_STORAGE_OPERATION_ERASE_ALL,
00219   ARM_STORAGE_OPERATION_GET_STATUS,
00220   ARM_STORAGE_OPERATION_GET_INFO,
00221   ARM_STORAGE_OPERATION_RESOLVE_ADDRESS,
00222   ARM_STORAGE_OPERATION_GET_NEXT_BLOCK,
00223   ARM_STORAGE_OPERATION_GET_BLOCK
00224 } ARM_STORAGE_OPERATION;
00225 
00226 /**
00227  * Declaration of the callback-type for command completion.
00228  *
00229  * @param [in] status
00230  *               A code to indicate the status of the completed operation. For data
00231  *               transfer operations, the status field is overloaded in case of
00232  *               success to return the count of items successfully transferred; this
00233  *               can be done safely because error codes are negative values.
00234  *
00235  * @param [in] operation
00236  *               The command op-code. This value isn't essential for the callback in
00237  *               the presence of the command instance-id, but it is expected that
00238  *               this information could be a quick and useful filter.
00239  */
00240 typedef void (*ARM_Storage_Callback_t)(int32_t status, ARM_STORAGE_OPERATION operation);
00241 
00242 /**
00243  * This is the set of operations constituting the Storage driver. Their
00244  * implementation is platform-specific, and needs to be supplied by the
00245  * porting effort.
00246  *
00247  * Some APIs within `ARM_DRIVER_STORAGE` will always operate synchronously:
00248  * GetVersion, GetCapabilities, GetStatus, GetInfo, ResolveAddress,
00249  * GetNextBlock, and GetBlock. This means that control returns to the caller
00250  * with a relevant status code only after the completion of the operation (or
00251  * the discovery of a failure condition).
00252  *
00253  * The remainder of the APIs: Initialize, Uninitialize, PowerControl, ReadData,
00254  * ProgramData, Erase, EraseAll, can function asynchronously if the underlying
00255  * controller supports it--i.e. if ARM_STORAGE_CAPABILITIES::asynchronous_ops is
00256  * set. In the case of asynchronous operation, the invocation returns early
00257  * (with ARM_DRIVER_OK) and results in a completion callback later. If
00258  * ARM_STORAGE_CAPABILITIES::asynchronous_ops is not set, then all such APIs
00259  * execute synchronously, and control returns to the caller with a status code
00260  * only after the completion of the operation (or the discovery of a failure
00261  * condition).
00262  *
00263  * If ARM_STORAGE_CAPABILITIES::asynchronous_ops is set, a storage driver may
00264  * still choose to execute asynchronous operations in a synchronous manner. If
00265  * so, the driver returns a positive value to indicate successful synchronous
00266  * completion (or an error code in case of failure) and no further invocation of
00267  * completion callback should be expected. The expected return value for
00268  * synchronous completion of such asynchronous operations varies depending on
00269  * the operation. For operations involving data access, it often equals the
00270  * amount of data transferred or affected. For non data-transfer operations,
00271  * such as EraseAll or Initialize, it is usually 1.
00272  *
00273  * Here's a code snippet to suggest how asynchronous APIs might be used by
00274  * callers to handle both synchronous and asynchronous execution by the
00275  * underlying storage driver:
00276  * \code
00277  *     ASSERT(ARM_DRIVER_OK == 0); // this is a precondition; it doesn't need to be put in code
00278  *     int32_t returnValue = drv->asynchronousAPI(...);
00279  *     if (returnValue < ARM_DRIVER_OK) {
00280  *         // handle error.
00281  *     } else if (returnValue == ARM_DRIVER_OK) {
00282  *         ASSERT(drv->GetCapabilities().asynchronous_ops == 1);
00283  *         // handle early return from asynchronous execution; remainder of the work is done in the callback handler.
00284  *     } else {
00285  *         ASSERT(returnValue == EXPECTED_RETURN_VALUE_FOR_SYNCHRONOUS_COMPLETION);
00286  *         // handle synchronous completion.
00287  *     }
00288  * \endcode
00289  */
00290 typedef struct _ARM_DRIVER_STORAGE {
00291   /**
00292    * \brief Get driver version.
00293    *
00294    * The function GetVersion() returns version information of the driver implementation in ARM_DRIVER_VERSION.
00295    *
00296    *    - API version is the version of the CMSIS-Driver specification used to implement this driver.
00297    *    - Driver version is source code version of the actual driver implementation.
00298    *
00299    * Example:
00300    * \code
00301    *     extern ARM_DRIVER_STORAGE *drv_info;
00302    *
00303    *     void read_version (void)  {
00304    *       ARM_DRIVER_VERSION  version;
00305    *
00306    *       version = drv_info->GetVersion ();
00307    *       if (version.api < 0x10A)   {      // requires at minimum API version 1.10 or higher
00308    *         // error handling
00309    *         return;
00310    *       }
00311    *     }
00312    * \endcode
00313    *
00314    * @return \ref ARM_DRIVER_VERSION.
00315    *
00316    * @note This API returns synchronously--it does not result in an invocation
00317    *     of a completion callback.
00318    *
00319    * @note The function GetVersion() can be called any time to obtain the
00320    *     required information from the driver (even before initialization). It
00321    *     always returns the same information.
00322    */
00323   ARM_DRIVER_VERSION (*GetVersion)(void);
00324 
00325   /**
00326    * \brief Get driver capabilities.
00327    *
00328    * \details The function GetCapabilities() returns information about
00329    * capabilities in this driver implementation. The data fields of the struct
00330    * ARM_STORAGE_CAPABILITIES encode various capabilities, for example if the device
00331    * is able to execute operations asynchronously.
00332    *
00333    * Example:
00334    * \code
00335    *     extern ARM_DRIVER_STORAGE *drv_info;
00336    *
00337    *     void read_capabilities (void)  {
00338    *       ARM_STORAGE_CAPABILITIES drv_capabilities;
00339    *
00340    *       drv_capabilities = drv_info->GetCapabilities ();
00341    *       // interrogate capabilities
00342    *
00343    *     }
00344    * \endcode
00345    *
00346    * @return \ref ARM_STORAGE_CAPABILITIES.
00347    *
00348    * @note This API returns synchronously--it does not result in an invocation
00349    *     of a completion callback.
00350    *
00351    * @note The function GetCapabilities() can be called any time to obtain the
00352    *     required information from the driver (even before initialization). It
00353    *     always returns the same information.
00354    */
00355   ARM_STORAGE_CAPABILITIES (*GetCapabilities)(void);
00356 
00357   /**
00358    * \brief Initialize the Storage Interface.
00359    *
00360    * The function Initialize is called when the middleware component starts
00361    * operation. In addition to bringing the controller to a ready state,
00362    * Initialize() receives a callback handler to be invoked upon completion of
00363    * asynchronous operations.
00364    *
00365    * Initialize() needs to be called explicitly before
00366    * powering the peripheral using PowerControl(), and before initiating other
00367    * accesses to the storage controller.
00368    *
00369    * The function performs the following operations:
00370    *   - Initializes the resources needed for the Storage interface.
00371    *   - Registers the \ref ARM_Storage_Callback_t callback function.
00372    *
00373    * To start working with a peripheral the functions Initialize and PowerControl need to be called in this order:
00374    *     drv->Initialize (...); // Allocate I/O pins
00375    *     drv->PowerControl (ARM_POWER_FULL);        // Power up peripheral, setup IRQ/DMA
00376    *
00377    * - Initialize() typically allocates the I/O resources (pins) for the
00378    *   peripheral. The function can be called multiple times; if the I/O resources
00379    *   are already initialized it performs no operation and just returns with
00380    *   ARM_DRIVER_OK.
00381    *
00382    * - PowerControl (ARM_POWER_FULL) sets the peripheral registers including
00383    *   interrupt (NVIC) and optionally DMA. The function can be called multiple
00384    *   times; if the registers are already set it performs no operation and just
00385    *   returns with ARM_DRIVER_OK.
00386    *
00387    * To stop working with a peripheral the functions PowerControl and Uninitialize need to be called in this order:
00388    *     drv->PowerControl (ARM_POWER_OFF);     // Terminate any pending transfers, reset IRQ/DMA, power off peripheral
00389    *     drv->Uninitialize (...);               // Release I/O pins
00390    *
00391    * The functions PowerControl and Uninitialize always execute and can be used
00392    * to put the peripheral into a Safe State, for example after any data
00393    * transmission errors. To restart the peripheral in an error condition,
00394    * you should first execute the Stop Sequence and then the Start Sequence.
00395    *
00396    * @param [in] callback
00397    *               Caller-defined callback to be invoked upon command completion
00398    *               for asynchronous APIs (including the completion of
00399    *               initialization). Use a NULL pointer when no callback
00400    *               signals are required.
00401    *
00402    * @note This API may execute asynchronously if
00403    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00404    *     execution is optional even if 'asynchronous_ops' is set.
00405    *
00406    * @return If asynchronous activity is launched, an invocation returns
00407    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00408    *     future with a status value of ARM_DRIVER_OK or an error-code. In the
00409    *     case of synchronous execution, control returns after completion with a
00410    *     value of 1. Return values less than ARM_DRIVER_OK (0) signify errors.
00411    */
00412   int32_t (*Initialize)(ARM_Storage_Callback_t callback);
00413 
00414   /**
00415    * \brief De-initialize the Storage Interface.
00416    *
00417    * The function Uninitialize() de-initializes the resources of Storage interface.
00418    *
00419    * It is called when the middleware component stops operation, and wishes to
00420    * release the software resources used by the interface.
00421    *
00422    * @note This API may execute asynchronously if
00423    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00424    *     execution is optional even if 'asynchronous_ops' is set.
00425    *
00426    * @return If asynchronous activity is launched, an invocation returns
00427    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00428    *     future with a status value of ARM_DRIVER_OK or an error-code. In the
00429    *     case of synchronous execution, control returns after completion with a
00430    *     value of 1. Return values less than ARM_DRIVER_OK (0) signify errors.
00431    */
00432   int32_t (*Uninitialize)(void);
00433 
00434   /**
00435    * \brief Control the Storage interface power.
00436    *
00437    * The function \b ARM_Storage_PowerControl operates the power modes of the Storage interface.
00438    *
00439    * To start working with a peripheral the functions Initialize and PowerControl need to be called in this order:
00440    *     drv->Initialize (...);                 // Allocate I/O pins
00441    *     drv->PowerControl (ARM_POWER_FULL);    // Power up peripheral, setup IRQ/DMA
00442    *
00443    * - Initialize() typically allocates the I/O resources (pins) for the
00444    *   peripheral. The function can be called multiple times; if the I/O resources
00445    *   are already initialized it performs no operation and just returns with
00446    *   ARM_DRIVER_OK.
00447    *
00448    * - PowerControl (ARM_POWER_FULL) sets the peripheral registers including
00449    *   interrupt (NVIC) and optionally DMA. The function can be called multiple
00450    *   times; if the registers are already set it performs no operation and just
00451    *   returns with ARM_DRIVER_OK.
00452    *
00453    * To stop working with a peripheral the functions PowerControl and Uninitialize need to be called in this order:
00454    *
00455    *     drv->PowerControl (ARM_POWER_OFF);     // Terminate any pending transfers, reset IRQ/DMA, power off peripheral
00456    *     drv->Uninitialize (...);               // Release I/O pins
00457    *
00458    * The functions PowerControl and Uninitialize always execute and can be used
00459    * to put the peripheral into a Safe State, for example after any data
00460    * transmission errors. To restart the peripheral in an error condition,
00461    * you should first execute the Stop Sequence and then the Start Sequence.
00462    *
00463    * @param state
00464    *          \ref ARM_POWER_STATE. The target power-state for the storage controller.
00465    *          The parameter state can have the following values:
00466    *              - ARM_POWER_FULL : set-up peripheral for data transfers, enable interrupts
00467    *                                 (NVIC) and optionally DMA. Can be called multiple times. If the peripheral
00468    *                                 is already in this mode, then the function performs no operation and returns
00469    *                                 with ARM_DRIVER_OK.
00470    *              - ARM_POWER_LOW : may use power saving. Returns ARM_DRIVER_ERROR_UNSUPPORTED when not implemented.
00471    *              - ARM_POWER_OFF : terminates any pending data transfers, disables peripheral, disables related interrupts and DMA.
00472    *
00473    * @note This API may execute asynchronously if
00474    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00475    *     execution is optional even if 'asynchronous_ops' is set.
00476    *
00477    * @return If asynchronous activity is launched, an invocation returns
00478    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00479    *     future with a status value of ARM_DRIVER_OK or an error-code. In the
00480    *     case of synchronous execution, control returns after completion with a
00481    *     value of 1. Return values less than ARM_DRIVER_OK (0) signify errors.
00482    */
00483   int32_t (*PowerControl)(ARM_POWER_STATE state);
00484 
00485   /**
00486    * \brief read the contents of a given address range from the storage device.
00487    *
00488    * \details Read the contents of a range of storage memory into a buffer
00489    *   supplied by the caller. The buffer is owned by the caller and should
00490    *   remain accessible for the lifetime of this command.
00491    *
00492    * @param  [in] addr
00493    *                This specifies the address from where to read data.
00494    *
00495    * @param [out] data
00496    *                The destination of the read operation. The buffer
00497    *                is owned by the caller and should remain accessible for the
00498    *                lifetime of this command.
00499    *
00500    * @param  [in] size
00501    *                The number of bytes requested to read. The data buffer
00502    *                should be at least as large as this size.
00503    *
00504    * @note This API may execute asynchronously if
00505    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00506    *     execution is optional even if 'asynchronous_ops' is set.
00507    *
00508    * @return If asynchronous activity is launched, an invocation returns
00509    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00510    *     future with the number of successfully transferred bytes passed in as
00511    *     the 'status' parameter. In the case of synchronous execution, control
00512    *     returns after completion with a positive transfer-count. Return values
00513    *     less than ARM_DRIVER_OK (0) signify errors.
00514    */
00515   int32_t (*ReadData)(uint64_t addr, void *data, uint32_t size);
00516 
00517   /**
00518    * \brief program (write into) the contents of a given address range of the storage device.
00519    *
00520    * \details Write the contents of a given memory buffer into a range of
00521    *   storage memory. In the case of flash memory, the destination range in
00522    *   storage memory typically has its contents in an erased state from a
00523    *   preceding erase operation. The source memory buffer is owned by the
00524    *   caller and should remain accessible for the lifetime of this command.
00525    *
00526    * @param [in] addr
00527    *               This is the start address of the range to be written into. It
00528    *               needs to be aligned to the device's \em program_unit
00529    *               specified in \ref ARM_STORAGE_INFO.
00530    *
00531    * @param [in] data
00532    *               The source of the write operation. The buffer is owned by the
00533    *               caller and should remain accessible for the lifetime of this
00534    *               command.
00535    *
00536    * @param [in] size
00537    *               The number of bytes requested to be written. The buffer
00538    *               should be at least as large as this size. \note 'size' should
00539    *               be a multiple of the device's 'program_unit' (see \ref
00540    *               ARM_STORAGE_INFO).
00541    *
00542    * @note It is best for the middleware to write in units of
00543    *     'optimal_program_unit' (\ref ARM_STORAGE_INFO) of the device.
00544    *
00545    * @note This API may execute asynchronously if
00546    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00547    *     execution is optional even if 'asynchronous_ops' is set.
00548    *
00549    * @return If asynchronous activity is launched, an invocation returns
00550    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00551    *     future with the number of successfully transferred bytes passed in as
00552    *     the 'status' parameter. In the case of synchronous execution, control
00553    *     returns after completion with a positive transfer-count. Return values
00554    *     less than ARM_DRIVER_OK (0) signify errors.
00555    */
00556   int32_t (*ProgramData)(uint64_t addr, const void *data, uint32_t size);
00557 
00558   /**
00559    * @brief Erase Storage range.
00560    *
00561    * @details This function erases a range of storage specified by [addr, addr +
00562    *     size). Both 'addr' and 'addr + size' should align with the
00563    *     'erase_unit'(s) of the respective owning storage block(s) (see \ref
00564    *     ARM_STORAGE_BLOCK and \ref ARM_STORAGE_BLOCK_ATTRIBUTES). The range to
00565    *     be erased will have its contents returned to the un-programmed state--
00566    *     i.e. to 'erased_value' (see \ref ARM_STORAGE_BLOCK_ATTRIBUTES), which
00567    *     is usually 1 to indicate the pattern of all ones: 0xFF.
00568    *
00569    * @param [in] addr
00570    *               This is the start-address of the range to be erased. It must
00571    *               start at an 'erase_unit' boundary of the underlying block.
00572    *
00573    * @param [in] size
00574    *               Size (in bytes) of the range to be erased. 'addr + size'
00575    *               must be aligned with the 'erase_unit' of the underlying
00576    *               block.
00577    *
00578    * @note This API may execute asynchronously if
00579    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00580    *     execution is optional even if 'asynchronous_ops' is set.
00581    *
00582    * @return
00583    *   If the range to be erased doesn't align with the erase_units of the
00584    *   respective start and end blocks, ARM_DRIVER_ERROR_PARAMETER is returned.
00585    *   If any part of the range is protected, ARM_STORAGE_ERROR_PROTECTED is
00586    *   returned. If any part of the range is not erasable,
00587    *   ARM_STORAGE_ERROR_NOT_ERASABLE is returned. All such sanity-check
00588    *   failures result in the error code being returned synchronously and the
00589    *   storage bytes within the range remain unaffected.
00590    *   Otherwise the function executes in the following ways:
00591    *     If asynchronous activity is launched, an invocation returns
00592    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00593    *     future with the number of successfully erased bytes passed in as
00594    *     the 'status' parameter. In the case of synchronous execution, control
00595    *     returns after completion with a positive erase-count. Return values
00596    *     less than ARM_DRIVER_OK (0) signify errors.
00597    *
00598    * @note Erase() may return a smaller (positive) value than the size of the
00599    *     requested range. The returned value indicates the actual number of bytes
00600    *     erased. It is the caller's responsibility to follow up with an appropriate
00601    *     request to complete the operation.
00602    *
00603    * @note in the case of a failed erase (except when
00604    *     ARM_DRIVER_ERROR_PARAMETER, ARM_STORAGE_ERROR_PROTECTED, or
00605    *     ARM_STORAGE_ERROR_NOT_ERASABLE is returned synchronously), the
00606    *     requested range should be assumed to be in an unknown state. The
00607    *     previous contents may not be retained.
00608    */
00609   int32_t (*Erase)(uint64_t addr, uint32_t size);
00610 
00611   /**
00612    * @brief Erase complete storage. Optional function for faster erase of the complete device.
00613    *
00614    * This optional function erases the complete device. If the device does not
00615    *    support global erase then the function returns the error value \ref
00616    *    ARM_DRIVER_ERROR_UNSUPPORTED. The data field \em 'erase_all' =
00617    *    \token{1} of the structure \ref ARM_STORAGE_CAPABILITIES encodes that
00618    *    \ref ARM_STORAGE_EraseAll is supported.
00619    *
00620    * @note This API may execute asynchronously if
00621    *     ARM_STORAGE_CAPABILITIES::asynchronous_ops is set. Asynchronous
00622    *     execution is optional even if 'asynchronous_ops' is set.
00623    *
00624    * @return
00625    *   If any part of the storage range is protected,
00626    *   ARM_STORAGE_ERROR_PROTECTED is returned. If any part of the storage
00627    *   range is not erasable, ARM_STORAGE_ERROR_NOT_ERASABLE is returned. All
00628    *   such sanity-check failures result in the error code being returned
00629    *   synchronously and the storage bytes within the range remain unaffected.
00630    *   Otherwise the function executes in the following ways:
00631    *     If asynchronous activity is launched, an invocation returns
00632    *     ARM_DRIVER_OK, and the caller can expect to receive a callback in the
00633    *     future with ARM_DRIVER_OK passed in as the 'status' parameter. In the
00634    *     case of synchronous execution, control returns after completion with a
00635    *     value of 1. Return values less than ARM_DRIVER_OK (0) signify errors.
00636    */
00637   int32_t (*EraseAll)(void);
00638 
00639   /**
00640    * @brief Get the status of the current (or previous) command executed by the
00641    *     storage controller; stored in the structure \ref ARM_STORAGE_STATUS.
00642    *
00643    * @return
00644    *          The status of the underlying controller.
00645    *
00646    * @note This API returns synchronously--it does not result in an invocation
00647    *     of a completion callback.
00648    */
00649   ARM_STORAGE_STATUS (*GetStatus)(void);
00650 
00651   /**
00652    * @brief Get information about the Storage device; stored in the structure \ref ARM_STORAGE_INFO.
00653    *
00654    * @param [out] info
00655    *                A caller-supplied buffer capable of being filled in with an
00656    *                \ref ARM_STORAGE_INFO.
00657    *
00658    * @return ARM_DRIVER_OK if a ARM_STORAGE_INFO structure containing top level
00659    *         metadata about the storage controller is filled into the supplied
00660    *         buffer, else an appropriate error value.
00661    *
00662    * @note It is the caller's responsibility to ensure that the buffer passed in
00663    *         is able to be initialized with a \ref ARM_STORAGE_INFO.
00664    *
00665    * @note This API returns synchronously--it does not result in an invocation
00666    *     of a completion callback.
00667    */
00668   int32_t (*GetInfo)(ARM_STORAGE_INFO *info);
00669 
00670   /**
00671    * \brief For memory-mapped storage, resolve an address relative to
00672    *     the storage controller into a memory address.
00673    *
00674    * @param addr
00675    *          This is the address for which we want a resolution to the
00676    *          processor's physical address space. It is an offset from the
00677    *          start of the storage map maintained by the owning storage
00678    *          controller.
00679    *
00680    * @return
00681    *          The resolved address in the processor's address space; else
00682    *          ARM_STORAGE_INVALID_ADDRESS, if no resolution is possible.
00683    *
00684    * @note This API returns synchronously. The invocation should return quickly,
00685    *     and result in a resolved address.
00686    */
00687   uint32_t (*ResolveAddress)(uint64_t addr);
00688 
00689   /**
00690    * @brief Advance to the successor of the current block (iterator), or fetch
00691    *     the first block (if 'prev_block' is passed in as NULL).
00692    *
00693    * @details This helper function fetches (an iterator to) the next block (or
00694    *     the first block if 'prev_block' is passed in as NULL). In the failure
00695    *     case, a terminating, invalid block iterator is filled into the out
00696    *     parameter: 'next_block'. In combination with \ref
00697    *     ARM_STORAGE_VALID_BLOCK(), it can be used to iterate over the sequence
00698    *     of blocks within the storage map:
00699    *
00700    * \code
00701    *   ARM_STORAGE_BLOCK block;
00702    *   for (drv->GetNextBlock(NULL, &block); ARM_STORAGE_VALID_BLOCK(&block); drv->GetNextBlock(&block, &block)) {
00703    *       // make use of block
00704    *   }
00705    * \endcode
00706    *
00707    * @param[in]  prev_block
00708    *               An existing block (iterator) within the same storage
00709    *               controller. The memory buffer holding this block is owned
00710    *               by the caller. This pointer may be NULL; if so, the
00711    *               invocation fills in the first block into the out parameter:
00712    *               'next_block'.
00713    *
00714    * @param[out] next_block
00715    *               A caller-owned buffer large enough to be filled in with
00716    *               the following ARM_STORAGE_BLOCK. It is legal to provide the
00717    *               same buffer using 'next_block' as was passed in with 'prev_block'. It
00718    *               is also legal to pass a NULL into this parameter if the
00719    *               caller isn't interested in populating a buffer with the next
00720    *               block--i.e. if the caller only wishes to establish the
00721    *               presence of a next block.
00722    *
00723    * @return ARM_DRIVER_OK if a valid next block is found (or first block, if
00724    *     prev_block is passed as NULL); upon successful operation, the contents
00725    *     of the next (or first) block are filled into the buffer pointed to by
00726    *     the parameter 'next_block' and ARM_STORAGE_VALID_BLOCK(next_block) is
00727    *     guaranteed to be true. Upon reaching the end of the sequence of blocks
00728    *     (iterators), or in case the driver is unable to fetch information about
00729    *     the next (or first) block, an error (negative) value is returned and an
00730    *     invalid StorageBlock is populated into the supplied buffer. If
00731    *     prev_block is NULL, the first block is returned.
00732    *
00733    * @note This API returns synchronously--it does not result in an invocation
00734    *     of a completion callback.
00735    */
00736    int32_t (*GetNextBlock)(const ARM_STORAGE_BLOCK* prev_block, ARM_STORAGE_BLOCK *next_block);
00737 
00738   /**
00739    * @brief Find the storage block (iterator) encompassing a given storage address.
00740    *
00741    * @param[in]  addr
00742    *               Storage address in bytes.
00743    *
00744    * @param[out] block
00745    *               A caller-owned buffer large enough to be filled in with the
00746    *               ARM_STORAGE_BLOCK encapsulating the given address. This value
00747    *               can also be passed in as NULL if the caller isn't interested
00748    *               in populating a buffer with the block--if the caller only
00749    *               wishes to establish the presence of a containing storage
00750    *               block.
00751    *
00752    * @return ARM_DRIVER_OK if a containing storage-block is found. In this case,
00753    *     if block is non-NULL, the buffer pointed to by it is populated with
00754    *     the contents of the storage block--i.e. if block is valid and a block is
00755    *     found, ARM_STORAGE_VALID_BLOCK(block) would return true following this
00756    *     call. If there is no storage block containing the given offset, or in
00757    *     case the driver is unable to resolve an address to a storage-block, an
00758    *     error (negative) value is returned and an invalid StorageBlock is
00759    *     populated into the supplied buffer.
00760    *
00761    * @note This API returns synchronously--it does not result in an invocation
00762    *     of a completion callback.
00763    */
00764   int32_t (*GetBlock)(uint64_t addr, ARM_STORAGE_BLOCK *block);
00765 } const ARM_DRIVER_STORAGE;
00766 
00767 #ifdef __cplusplus
00768 }
00769 #endif // __cplusplus
00770 
00771 #endif /* __DRIVER_STORAGE_H */
00772 
00773 /** @}*/