Increase maximum number of APs to 256.

README.md

@@ -196,7 +196,8 @@ The configuration menu allows the user to:
     * individual errors
     * BadRAM patterns
   * select which of the available CPU cores are used (at startup only)
-    * a maximum of 32 CPU cores can be selected, due to display limits
+    * a maximum of 256 CPU cores can be selected, due to memory and
+      display limits
     * the bootstrap processor (BSP) cannot be deselected
   * enable or disable the temperature display (at startup only)
   * enable or disable boot tracing for debug (at startup only)

boot/boot.h

@@ -8,10 +8,6 @@
  * Copyright (C) 2020-2022 Martin Whitaker.
  */
 
-#define MAX_APS 	64		/* Maximum number of active APs. This
-					   only affects memory footprint, so
-					   can be increased if needed */
-
 #define BSP_STACK_SIZE	16384		/* Stack size for the BSP */
 #define AP_STACK_SIZE	1024		/* Stack size for each AP */
 

system/smp.h

@@ -4,7 +4,7 @@
 /*
  * Provides support for multi-threaded operation.
  *
- * Copyright (C) 2020-2021 Martin Whitaker.
+ * Copyright (C) 2020-2022 Martin Whitaker.
  */
 
 #include <stdbool.h>
@@ -16,10 +16,11 @@
 #include "spinlock.h"
 
 /*
- * The maximum number of active physical CPUs. This only affects memory
- * footprint, so can be increased if needed.
+ * The maximum number of active physical CPUs. There must be room in
+ * low memory for the program and all the CPU stacks and also enough
+ * rows in the config pop-up window to display the enabled state.
  */
-#define MAX_PCPUS   (1 + MAX_APS)
+#define MAX_PCPUS   256
 
 /*
  * An error code returned by smp_start().