diff --git a/mboxd.c b/mboxd.c
index 6f060d8..0ebba56 100644
--- a/mboxd.c
+++ b/mboxd.c
@@ -53,13 +53,15 @@
 
 #define USAGE \
 "\nUsage: %s [-V | --version] [-h | --help] [-v[v] | --verbose] [-s | --syslog]\n" \
-"\t\t-n | --window-num <num>\n" \
-"\t\t-w | --window-size <size>M\n" \
+"\t\t[-n | --window-num <num>]\n" \
+"\t\t[-w | --window-size <size>M]\n" \
 "\t\t-f | --flash <size>[K|M]\n\n" \
 "\t-v | --verbose\t\tBe [more] verbose\n" \
 "\t-s | --syslog\t\tLog output to syslog (pointless without -v)\n" \
 "\t-n | --window-num\tThe number of windows\n" \
+"\t\t\t\t(default: fill the reserved memory region)\n" \
 "\t-w | --window-size\tThe window size (power of 2) in MB\n" \
+"\t\t\t\t(default: 1MB)\n" \
 "\t-f | --flash\t\tSize of flash in [K|M] bytes\n\n"
 
 static int poll_loop(struct mbox_context *context)
@@ -179,7 +181,7 @@
 			  struct mbox_context *context)
 {
 	char *endptr;
-	int opt, i;
+	int opt;
 
 	static const struct option long_options[] = {
 		{ "flash",		required_argument,	0, 'f' },
@@ -195,9 +197,6 @@
 	verbosity = MBOX_LOG_NONE;
 	mbox_vlog = &mbox_log_console;
 
-	/* Default to 1 window of size flash_size */
-	context->windows.default_size = context->flash_size;
-	context->windows.num = 1;
 	context->current = NULL; /* No current window */
 
 	while ((opt = getopt_long(argc, argv, "f:w::n::vsVh", long_options, NULL))
@@ -269,34 +268,7 @@
 		return false;
 	}
 
-	if (!context->windows.num) {
-		fprintf(stderr, "Must specify a non-zero number of windows\n"
-				"If unsure - select 4 (-n 4)\n");
-		return false;
-	}
-
-	if (!context->windows.default_size) {
-		fprintf(stderr, "Must specify a non-zero window size\n"
-				"If unsure - select 1M (-w 1)\n");
-		return false;
-	}
-
 	MSG_OUT("Flash size: 0x%.8x\n", context->flash_size);
-	MSG_OUT("Number of Windows: %d\n", context->windows.num);
-	MSG_OUT("Window size: 0x%.8x\n", context->windows.default_size);
-
-	context->windows.window = calloc(context->windows.num,
-					 sizeof(*context->windows.window));
-	if (!context->windows.window) {
-		MSG_ERR("Memory allocation failed\n");
-		free(context);
-		exit(1);
-	}
-
-	for (i = 0; i < context->windows.num; i++) {
-		init_window_state(&context->windows.window[i],
-				  context->windows.default_size);
-	}
 
 	if (verbosity) {
 		MSG_OUT("%s logging\n", verbosity == MBOX_LOG_DEBUG ? "Debug" :
@@ -347,7 +319,7 @@
 	}
 
 	/* We've found the reserved memory region -> we can assign to windows */
-	rc = init_window_mem(context);
+	rc = init_windows(context);
 	if (rc) {
 		goto finish;
 	}
@@ -386,8 +358,7 @@
 	free_flash_dev(context);
 	free_lpc_dev(context);
 	free_mbox_dev(context);
-	free_window_dirty_bytemap(context);
-	free(context->windows.window);
+	free_windows(context);
 	free(context);
 
 	return rc;
diff --git a/mboxd_windows.c b/mboxd_windows.c
index fd46770..c64d19b 100644
--- a/mboxd_windows.c
+++ b/mboxd_windows.c
@@ -54,7 +54,7 @@
  * @window:	The window to initialise
  * @size:	The size of the window
  */
-void init_window_state(struct window_context *window, uint32_t size)
+static void init_window_state(struct window_context *window, uint32_t size)
 {
 	window->mem = NULL;
 	window->flash_offset = FLASH_OFFSET_UNINIT;
@@ -69,7 +69,7 @@
  *
  * Return:	0 on success otherwise negative error code
  */
-int init_window_mem(struct mbox_context *context)
+static int init_window_mem(struct mbox_context *context)
 {
 	void *mem_location = context->mem;
 	int i;
@@ -95,6 +95,60 @@
 
 	return 0;
 }
+/*
+ * init_windows() - Initalise the window cache
+ * @context:    The mbox context pointer
+ *
+ * Return:      0 on success otherwise negative
+ */
+int init_windows(struct mbox_context *context)
+{
+	int i;
+
+	/* Check if window size and number set - otherwise set to default */
+	if (!context->windows.default_size) {
+		/* Default to 1MB windows */
+		context->windows.default_size = 1 << 20;
+	}
+	MSG_OUT("Window size: 0x%.8x\n", context->windows.default_size);
+	if (!context->windows.num) {
+		/* Use the entire reserved memory region by default */
+		context->windows.num = context->mem_size /
+				       context->windows.default_size;
+	}
+	MSG_OUT("Number of Windows: %d\n", context->windows.num);
+
+	context->windows.window = calloc(context->windows.num,
+					 sizeof(*context->windows.window));
+	if (!context->windows.window) {
+		MSG_ERR("Memory allocation failed\n");
+		return -1;
+	}
+
+	for (i = 0; i < context->windows.num; i++) {
+		init_window_state(&context->windows.window[i],
+				  context->windows.default_size);
+	}
+
+	return init_window_mem(context);
+}
+
+/*
+ * free_windows() - Free the window cache
+ * @context:	The mbox context pointer
+ */
+void free_windows(struct mbox_context *context)
+{
+	int i;
+
+	/* Check window cache has actually been allocated */
+	if (context->windows.window) {
+		for (i = 0; i < context->windows.num; i++) {
+			free(context->windows.window[i].dirty_bmap);
+		}
+		free(context->windows.window);
+	}
+}
 
 /* Write from Window Functions */
 
@@ -310,19 +364,6 @@
 }
 
 /*
- * free_window_dirty_bytemap() - free all window dirty bytemaps
- * @context:	The mbox context pointer
- */
-void free_window_dirty_bytemap(struct mbox_context *context)
-{
-	int i;
-
-	for (i = 0; i < context->windows.num; i++) {
-		free(context->windows.window[i].dirty_bmap);
-	}
-}
-
-/*
  * set_window_bytemap() - Set the window bytemap
  * @context:	The mbox context pointer
  * @cur:	The window to set the bytemap of
diff --git a/mboxd_windows.h b/mboxd_windows.h
index 90e1d46..b81007d 100644
--- a/mboxd_windows.h
+++ b/mboxd_windows.h
@@ -22,8 +22,8 @@
 #define WITH_FLUSH	true
 
 /* Initialisation Functions */
-void init_window_state(struct window_context *window, uint32_t size);
-int init_window_mem(struct mbox_context *context);
+int init_windows(struct mbox_context *context);
+void free_windows(struct mbox_context *context);
 /* Write From Window Functions */
 int write_from_window_v1(struct mbox_context *context,
 			 uint32_t offset_bytes, uint32_t count_bytes);
@@ -31,7 +31,6 @@
 		      uint32_t count, uint8_t type);
 /* Window Management Functions */
 void alloc_window_dirty_bytemap(struct mbox_context *context);
-void free_window_dirty_bytemap(struct mbox_context *context);
 int set_window_bytemap(struct mbox_context *context, struct window_context *cur,
 		       uint32_t offset, uint32_t size, uint8_t val);
 void close_current_window(struct mbox_context *context, bool set_bmc_event,