diff --git a/doc/framework.md b/doc/framework.md
index 501c8d3c728b0cda3f03e7822a1945b7c1d48c81..4672c7ed7d1c10bbad1ebda5cbd5df133cbadd38 100644
--- a/doc/framework.md
+++ b/doc/framework.md
@@ -85,7 +85,9 @@ If a dual-region memory configuration is used then *FIRMWARE_MEM1_BASE* and
 It is the responsibility of the firmware to define - in its Makefile - the
 architecture target for the image (using *BS_FIRMWARE_CPU*) and whether the
 firmware is multithreading-enabled (using *BS_FIRMWARE_HAS_MULTITHREADING*)
-and/or has notification support (using *BS_FIRMWARE_HAS_NOTIFICATION*).
+and/or has notification support (using *BS_FIRMWARE_HAS_NOTIFICATION*). The
+firmware can optionally define the count of notification subscriptions
+(using *BS_FIRMWARE_NOTIFICATION_COUNT*) to be supported.
 
 An example of a simple firmware directory which contains configuration files for
 two modules, the firmware.mk file, and the linker script.
diff --git a/framework/src/fwk_module.c b/framework/src/fwk_module.c
index 389687e9e34394e1f70115f1c5dac5ad07e276df..6f3e29ad5ffdeb215c52881e581be24b48fdfb43 100644
--- a/framework/src/fwk_module.c
+++ b/framework/src/fwk_module.c
@@ -20,9 +20,12 @@
 #endif
 
 #define EVENT_COUNT 64
-#define NOTIFICATION_COUNT 64
 #define BIND_ROUND_MAX 1
 
+#ifndef NOTIFICATION_COUNT
+#define NOTIFICATION_COUNT 64
+#endif
+
 /* Pre-runtime phase stages */
 enum module_stage {
     MODULE_STAGE_INITIALIZE,
diff --git a/module/system_pll/include/mod_system_pll.h b/module/system_pll/include/mod_system_pll.h
index 03b30fad960627d2f0ba773ccba0128b8f8a1da0..e16c1257c0e7048a2534851d4590c02b60f3194f 100644
--- a/module/system_pll/include/mod_system_pll.h
+++ b/module/system_pll/include/mod_system_pll.h
@@ -50,7 +50,7 @@ struct mod_system_pll_dev_config {
      * Mask for the bit within the status register that indicates whether the
      * PLL has locked at the programmed rate.
      */
-    const uint8_t lock_flag_mask;
+    const uint32_t lock_flag_mask;
 
     /*! The initial rate the PLL is set to during initialization. */
     const uint64_t initial_rate;
diff --git a/tools/build_system/doc.md b/tools/build_system/doc.md
index 92671b26c79262ad75ff24141830498cf8ec49f0..7067bf20bc4561a912512fefea8f49f5a8ace346 100644
--- a/tools/build_system/doc.md
+++ b/tools/build_system/doc.md
@@ -65,6 +65,9 @@ The following parameters are mandatory:
   to yes, firmware will be built with multithreading support.
 * __BS_FIRMWARE_HAS_NOTIFICATION__ <yes|no> - Notification support. When set
   to yes, firmware will be built with notification support.
+* __BS_FIRMWARE_NOTIFICATION_COUNT__ < count > - When notification support is set
+  to yes, firmware can optinally specifiy the number notfication subscriptions
+  to be supported.
 * __BS_FIRMWARE_MODULES__ - The list of modules to be included and built into
   the firmware and any APIs to be omitted from each module.
 * __BS_FIRMWARE_MODULE_HEADERS_ONLY__ - The list of modules to have their header
@@ -176,13 +179,19 @@ Notification Support                                     {#section_notification}
 
 When building a firmware and its dependencies, the
 BS_FIRMWARE_HAS_NOTIFICATION parameter controls whether notification support
-is enabled or not.
+is enabled or not. If notification support is enabled, the firmware can define
+the number of notification subscriptions supported on the platform using
+BS_FIRMWARE_NOTIFICATION_COUNT parameter.
 
 When notification support is enabled, the following applies:
 
 * The BUILD_HAS_NOTIFICATION definition is defined for the units being built.
 * Notification specific APIs are made available to the modules via the
   framework components (see \ref GroupLibFramework).
+* The BUILD_NOTIFICATION_COUNT definition is defined if the optional
+  parameter BS_FIRMWARE_NOTIFICATION_COUNT is defined. It specified the
+  number of notification subscriptions supported and set to the value
+  defined by BS_FIRMWARE_NOTIFICATION_COUNT parameter.
 
 Definitions
 ===========
diff --git a/tools/build_system/firmware.mk b/tools/build_system/firmware.mk
index 90feab02b6f2d191ae79b2c19929f0cc3e39a854..e2b4649d9d25c1fc2121f339aeb46ee7cb1f4412 100644
--- a/tools/build_system/firmware.mk
+++ b/tools/build_system/firmware.mk
@@ -204,6 +204,13 @@ else
 endif
 export BUILD_HAS_NOTIFICATION
 
+ifeq ($(BUILD_HAS_NOTIFICATION),yes)
+    ifdef BS_FIRMWARE_NOTIFICATION_COUNT
+        BUILD_NOTIFICATION_COUNT=$(BS_FIRMWARE_NOTIFICATION_COUNT)
+    endif
+    export BUILD_NOTIFICATION_COUNT
+endif
+
 # Add directories to the list of targets to build
 LIB_TARGETS_y += $(patsubst %,$(MODULES_DIR)/%/src, \
                             $(BUILD_STANDARD_MODULES))
diff --git a/tools/build_system/rules.mk b/tools/build_system/rules.mk
index 1fa2c5dd17385e8b64db7b5fe198dc10ae54a3ee..67bb655d1a2cd9c62e732031dd2cac2e32503dc7 100644
--- a/tools/build_system/rules.mk
+++ b/tools/build_system/rules.mk
@@ -21,6 +21,10 @@ ifeq ($(BUILD_HAS_NOTIFICATION),yes)
     DEFINES += BUILD_HAS_NOTIFICATION
 endif
 
+ifdef BUILD_NOTIFICATION_COUNT
+    DEFINES += NOTIFICATION_COUNT=$(BUILD_NOTIFICATION_COUNT)
+endif
+
 export AS := $(CC)
 export LD := $(CC)