Merge pull request #3 from ARMmbed/david_init_changes

Change driver initialization behavior:

FlashIAPBlockDevice.cpp

@@ -17,6 +17,7 @@
 #ifdef DEVICE_FLASH
 
 #include "FlashIAPBlockDevice.h"
+#include "mbed_critical.h"
 
 #include "mbed.h"
 
@@ -35,23 +36,67 @@
 #define DEBUG_PRINTF(...)
 #endif
 
-FlashIAPBlockDevice::FlashIAPBlockDevice(uint32_t address, uint32_t size)
+FlashIAPBlockDevice::FlashIAPBlockDevice()
-    : _flash(), _base(address), _size(size)
+    : _flash(), _base(0), _size(0), _is_initialized(false), _init_ref_count(0)
 {
     DEBUG_PRINTF("FlashIAPBlockDevice: %" PRIX32 " %" PRIX32 "\r\n", address, size);
 }
 
+FlashIAPBlockDevice::FlashIAPBlockDevice(uint32_t address, uint32_t)
+    : _flash(), _base(0), _size(0), _is_initialized(false), _init_ref_count(0)
+{
+
+}
+
+FlashIAPBlockDevice::~FlashIAPBlockDevice()
+{
+    deinit();
+}
+
 int FlashIAPBlockDevice::init()
 {
     DEBUG_PRINTF("init\r\n");
 
-    return _flash.init();
+    if (!_is_initialized) {
+        _init_ref_count = 0;
+    }
+
+    uint32_t val = core_util_atomic_incr_u32(&_init_ref_count, 1);
+
+    if (val != 1) {
+        return BD_ERROR_OK;
+    }
+
+    int ret = _flash.init();
+
+    if (ret) {
+        return ret;
+    }
+
+    _base = _flash.get_flash_start();
+    _size = _flash.get_flash_size();
+
+    _is_initialized = true;
+    return ret;
 }
 
 int FlashIAPBlockDevice::deinit()
 {
     DEBUG_PRINTF("deinit\r\n");
 
+    if (!_is_initialized) {
+        _init_ref_count = 0;
+        return 0;
+    }
+
+    uint32_t val = core_util_atomic_decr_u32(&_init_ref_count, 1);
+
+    if (val) {
+        return 0;
+    }
+
+    _is_initialized = false;
+
     return _flash.deinit();
 }
 
@@ -65,7 +110,7 @@ int FlashIAPBlockDevice::read(void *buffer,
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* Check that the address and size are properly aligned and fit. */
-    if (is_valid_read(virtual_address, size)) {
+    if (_is_initialized && is_valid_read(virtual_address, size)) {
 
         /* Convert virtual address to the physical address for the device. */
         bd_addr_t physical_address = _base + virtual_address;
@@ -89,7 +134,7 @@ int FlashIAPBlockDevice::program(const void *buffer,
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* Check that the address and size are properly aligned and fit. */
-    if (is_valid_program(virtual_address, size)) {
+    if (_is_initialized && is_valid_program(virtual_address, size)) {
 
         /* Convert virtual address to the physical address for the device. */
         bd_addr_t physical_address = _base + virtual_address;
@@ -114,7 +159,7 @@ int FlashIAPBlockDevice::erase(bd_addr_t virtual_address,
     int result = BD_ERROR_DEVICE_ERROR;
 
     /* Check that the address and size are properly aligned and fit. */
-    if (is_valid_erase(virtual_address, size)) {
+    if (_is_initialized && is_valid_erase(virtual_address, size)) {
 
         /* Convert virtual address to the physical address for the device. */
         bd_addr_t physical_address = _base + virtual_address;
@@ -135,6 +180,10 @@ bd_size_t FlashIAPBlockDevice::get_read_size() const
 
 bd_size_t FlashIAPBlockDevice::get_program_size() const
 {
+    if (!_is_initialized) {
+        return 0;
+    }
+
     uint32_t page_size = _flash.get_page_size();
 
     DEBUG_PRINTF("get_program_size: %" PRIX32 "\r\n", page_size);
@@ -144,6 +193,10 @@ bd_size_t FlashIAPBlockDevice::get_program_size() const
 
 bd_size_t FlashIAPBlockDevice::get_erase_size() const
 {
+    if (!_is_initialized) {
+        return 0;
+    }
+
     uint32_t erase_size = _flash.get_sector_size(_base);
 
     DEBUG_PRINTF("get_erase_size: %" PRIX32 "\r\n", erase_size);
@@ -153,6 +206,10 @@ bd_size_t FlashIAPBlockDevice::get_erase_size() const
 
 bd_size_t FlashIAPBlockDevice::get_erase_size(bd_addr_t addr) const
 {
+    if (!_is_initialized) {
+        return 0;
+    }
+
     uint32_t erase_size = _flash.get_sector_size(_base + addr);
 
     DEBUG_PRINTF("get_erase_size: %" PRIX32 "\r\n", erase_size);

FlashIAPBlockDevice.h

@@ -22,14 +22,6 @@
 #include "BlockDevice.h"
 #include <mbed.h>
 
-#ifndef MBED_CONF_FLASHIAP_BLOCK_DEVICE_BASE_ADDRESS
-#error flashiap-block-device.base-address not set
-#endif
-
-#ifndef MBED_CONF_FLASHIAP_BLOCK_DEVICE_SIZE
-#error flashiap-block-device.size not set
-#endif
-
 /** BlockDevice using the FlashIAP API
  *
  *  @code
@@ -39,14 +31,13 @@
  */
 class FlashIAPBlockDevice : public BlockDevice {
 public:
-    /** Creates a FlashIAPBlockDevice, starting at the given address and
+    /** Creates a FlashIAPBlockDevice **/
-     *  with a certain size.
+    FlashIAPBlockDevice();
-     *
+
-     *  @param address  Starting address for the BlockDevice
+    MBED_DEPRECATED("Please use default constructor instead")
-     *  @param size     Maximum size allocated to this BlockDevice
+    FlashIAPBlockDevice(uint32_t address, uint32_t size = 0);
-     */
+
-    FlashIAPBlockDevice(uint32_t address = MBED_CONF_FLASHIAP_BLOCK_DEVICE_BASE_ADDRESS,
+    virtual ~FlashIAPBlockDevice();
-                        uint32_t size = MBED_CONF_FLASHIAP_BLOCK_DEVICE_SIZE);
 
     /** Initialize a block device
      *
@@ -129,6 +120,8 @@ private:
     FlashIAP _flash;
     bd_addr_t _base;
     bd_size_t _size;
+    bool _is_initialized;
+    uint32_t _init_ref_count;
 };
 
 #endif /* DEVICE_FLASH */

README.md

@@ -6,27 +6,13 @@ This driver is **EXPERIMENTAL** and improper usage could kill your board's flash
 This driver should only be used on platforms where the FlashIAP implementation is using external flash or in conjunction with a filesystem with wear leveling, that can operate on a page size granularity.
 
 Additional concerns:
-- The BlockDevice API assumes a uniform erase size so the underlying flash must also have uniform sectors.
 - The FlashIAP may freeze code execution for a long period of time while writing to flash. Not even high-priority irqs will be allowed to run, which may interrupt background processes.
 
 
 ## Configuration
-
+None.
-The driver must be configured with the starting address for the internal flash area reserved for the block device and it's size in bytes. In the application's `mbed_app.json`, add the following lines:
-
-```json
-{
-    "target_overrides": {
-        "K64F": {
-            "flashiap-block-device.base-address": "<internal flash address where the block device starts>",
-            "flashiap-block-device.size": "<number of bytes allocated to the internal flash block device>"
-        }
-    }
-}
-```
-
 
 ## Tested on
 
-* Realtek RTL8195AM
+* K82F
 * K64F

mbed_lib.json

@@ -1,19 +0,0 @@
-{
-    "name": "flashiap-block-device",
-    "config": {
-        "base-address": {
-            "help": "Base address for the block device on the external flash.",
-            "value": "0xFFFFFFFF"
-        },
-        "size": {
-            "help": "Memory allocated for block device.",
-            "value": "0"
-        }
-    },
-    "target_overrides": {
-        "REALTEK_RTL8195AM": {
-            "base-address": "0x1C0000",
-            "size": "0x40000"
-        }
-    }
-}