allocator: Improve rfree() debug and trace

System heap is one time allocate only meant for init and not for freeing.
Panic if someone attempts to free system heap.

Provide pointers and cpu core ID for any failures in trace .

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>

Author: lrgirdwo

src/lib/alloc.c

@@ -327,13 +327,12 @@ static void free_block(void *ptr)
 	int i;
 	int block;
 
-	/* sanity check */
-	if (ptr == NULL)
-		return;
-
 	heap = get_heap_from_ptr(ptr);
-	if (heap == NULL)
+	if (!heap) {
+		trace_error(TRACE_CLASS_MEM, "invalid heap %p cpu %d",
+			    (uintptr_t)ptr, cpu_get_id());
 		return;
+	}
 
 	/* find block that ptr belongs to */
 	for (i = 0; i < heap->blocks; i++) {
@@ -346,7 +345,8 @@ static void free_block(void *ptr)
 	}
 
 	/* not found */
-	trace_mem_error("eMF");
+	trace_error(TRACE_CLASS_MEM, "invalid ptr %p cpu %d",
+		    (uintptr_t)ptr, cpu_get_id());
 	return;
 
 found:
@@ -540,8 +540,25 @@ void *rballoc(int zone, uint32_t caps, size_t bytes)
 
 void rfree(void *ptr)
 {
+	struct mm_heap *cpu_heap;
 	uint32_t flags;
 
+	/* sanity check - NULL ptrs are fine */
+	if (!ptr)
+		return;
+
+	/* use the heap dedicated for the selected core */
+	cpu_heap = cache_to_uncache(memmap.system + cpu_get_id());
+
+	/* panic if pointer is from system heap */
+	if (ptr >= (void *)cpu_heap->heap &&
+	    ptr <= (void *)cpu_heap->heap + cpu_heap->size) {
+		trace_error(TRACE_CLASS_MEM, "attempt to free system heap %p cpu %d",
+			    (uintptr_t)ptr, cpu_get_id());
+		panic(SOF_IPC_PANIC_MEM);
+	}
+
+	/* free the block */
 	spin_lock_irq(&memmap.lock, flags);
 	free_block(ptr);
 	spin_unlock_irq(&memmap.lock, flags);