lib: sysmem: add sysmem_can_alloc() interface

Check if the region can be sysmem allocated.

Change-Id: I26a524c1597bee65ab1282da5ec373b9603866ba
Signed-off-by: Joseph Chen <chenjh@rock-chips.com>

include/sysmem.h

@@ -93,6 +93,16 @@ void *sysmem_alloc_base_by_name(const char *name,
 void *sysmem_fdt_reserve_alloc_base(const char *name,
 				    phys_addr_t base, phys_size_t size);
 
+/**
+ * sysmem_can_alloc() - Check if the region can be allocated
+ *
+ * @base: region base
+ * @size: region size
+ *
+ * @return true on okay.
+ */
+bool sysmem_can_alloc(phys_size_t base, phys_size_t size);
+
 /**
  * sysmem_free() - Free allocated sysmem region
  *
@@ -128,6 +138,11 @@ static inline void *sysmem_alloc(enum memblk_id id, phys_size_t size)
 	return malloc(size);
 }
 
+static inline bool sysmem_can_alloc(phys_size_t base, phys_size_t size)
+{
+	return true;
+}
+
 static inline void *sysmem_alloc_base(enum memblk_id id,
 				      phys_addr_t base, phys_size_t size)
 {

lib/sysmem.c

@@ -354,7 +354,7 @@ static void *sysmem_alloc_align_base(enum memblk_id id,
 				 name, (ulong)base, (ulong)(base + size),
 				 (ulong)paddr, (ulong)(paddr + size));
 			/* Free what we don't want allocated region */
-			if (lmb_free(&sysmem->lmb, paddr, alloc_size))
+			if (lmb_free(&sysmem->lmb, paddr, alloc_size) < 0)
 				SYSMEM_E("Failed to free \"%s\"\n", name);
 
 			goto out;
@@ -435,6 +435,38 @@ void *sysmem_fdt_reserve_alloc_base(const char *name,
 	return paddr;
 }
 
+bool sysmem_can_alloc(phys_size_t base, phys_size_t size)
+{
+	struct sysmem *sysmem = &plat_sysmem;
+	phys_addr_t alloc_base;
+	phys_addr_t paddr;
+	int ret;
+
+	if (!sysmem_has_init())
+		return false;
+
+	/* LMB is align down alloc mechanism */
+	alloc_base = base + size;
+	paddr = __lmb_alloc_base(&sysmem->lmb,
+				 size,
+				 SYSMEM_ALLOC_NO_ALIGN,
+				 alloc_base);
+	if (paddr) {
+		/* If free failed, return false */
+		ret = lmb_free(&sysmem->lmb, base, size);
+		if (ret < 0) {
+			SYSMEM_E("Can't free at 0x%08lx - 0x%08lx, ret=%d\n",
+				 (ulong)base, (ulong)(base + size), ret);
+			return false;
+		}
+	} else {
+		SYSMEM_D("Can't alloc at 0x%08lx - 0x%08lx\n",
+			 (ulong)base, (ulong)(base + size));
+	}
+
+	return (paddr == base) ? true : false;
+}
+
 int sysmem_free(phys_addr_t base)
 {
 	struct sysmem *sysmem = &plat_sysmem;