global_data: Reduce size of early-malloc vars

The early malloc region is normally quite small and is certainly less
than 4GB, so use a 32-bit value for the limit and pointer. Update the
comments for clarity while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/lib/bdinfo.c b/arch/arm/lib/bdinfo.c
index 7c49462..c7fff01 100644
--- a/arch/arm/lib/bdinfo.c
+++ b/arch/arm/lib/bdinfo.c
@@ -58,7 +58,7 @@
 	printf("Board Type  = %ld\n", gd->board_type);
 #endif
 #if CONFIG_IS_ENABLED(SYS_MALLOC_F)
-	printf("Early malloc usage: %lx / %x\n", gd->malloc_ptr,
+	printf("Early malloc usage: %x / %x\n", gd->malloc_ptr,
 	       CONFIG_VAL(SYS_MALLOC_F_LEN));
 #endif
 }
diff --git a/common/board_r.c b/common/board_r.c
index f445803..e88b7ea 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -192,7 +192,7 @@
 	ulong start;
 
 #if CONFIG_IS_ENABLED(SYS_MALLOC_F)
-	debug("Pre-reloc malloc() used %#lx bytes (%ld KB)\n", gd->malloc_ptr,
+	debug("Pre-reloc malloc() used %#x bytes (%d KB)\n", gd->malloc_ptr,
 	      gd->malloc_ptr / 1024);
 #endif
 	/* The malloc area is immediately below the monitor copy in DRAM */
diff --git a/common/malloc_simple.c b/common/malloc_simple.c
index 4e6d795..5a8ec53 100644
--- a/common/malloc_simple.c
+++ b/common/malloc_simple.c
@@ -23,7 +23,7 @@
 
 	addr = ALIGN(gd->malloc_base + gd->malloc_ptr, align);
 	new_ptr = addr + bytes - gd->malloc_base;
-	log_debug("size=%lx, ptr=%lx, limit=%lx: ", (ulong)bytes, new_ptr,
+	log_debug("size=%lx, ptr=%lx, limit=%x: ", (ulong)bytes, new_ptr,
 		  gd->malloc_limit);
 	if (new_ptr > gd->malloc_limit) {
 		log_err("alloc space exhausted\n");
@@ -87,6 +87,6 @@
 
 void malloc_simple_info(void)
 {
-	log_info("malloc_simple: %lx bytes used, %lx remain\n", gd->malloc_ptr,
+	log_info("malloc_simple: %x bytes used, %x remain\n", gd->malloc_ptr,
 		 CONFIG_VAL(SYS_MALLOC_F_LEN) - gd->malloc_ptr);
 }
diff --git a/common/spl/spl.c b/common/spl/spl.c
index d4ec86a..da110ee 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -782,7 +782,7 @@
 	}
 	if (CONFIG_IS_ENABLED(SYS_MALLOC_F) &&
 	    !IS_ENABLED(CONFIG_SPL_SYS_MALLOC_SIZE))
-		debug("SPL malloc() used 0x%lx bytes (%ld KB)\n",
+		debug("SPL malloc() used 0x%x bytes (%d KB)\n",
 		      gd_malloc_ptr(), gd_malloc_ptr() / 1024);
 
 	bootstage_mark_name(get_bootstage_id(false), "end phase");
@@ -901,7 +901,7 @@
 
 #if defined(CONFIG_SPL_SYS_MALLOC_SIMPLE) && CONFIG_IS_ENABLED(SYS_MALLOC_F)
 	if (CONFIG_SPL_STACK_R_MALLOC_SIMPLE_LEN) {
-		debug("SPL malloc() before relocation used 0x%lx bytes (%ld KB)\n",
+		debug("SPL malloc() before relocation used 0x%x bytes (%d KB)\n",
 		      gd->malloc_ptr, gd->malloc_ptr / 1024);
 		ptr -= CONFIG_SPL_STACK_R_MALLOC_SIMPLE_LEN;
 		gd->malloc_base = ptr;
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index 253dd21..b09d4bc 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -299,13 +299,13 @@
 	 */
 	unsigned long malloc_base;
 	/**
-	 * @malloc_limit: limit address of early malloc()
+	 * @malloc_limit: maximum size of early malloc()
 	 */
-	unsigned long malloc_limit;
+	unsigned int malloc_limit;
 	/**
-	 * @malloc_ptr: current address of early malloc()
+	 * @malloc_ptr: currently used bytes of early malloc()
 	 */
-	unsigned long malloc_ptr;
+	unsigned int malloc_ptr;
 #endif
 #ifdef CONFIG_CONSOLE_RECORD
 	/**