efi/dtb: Fix dtb malloc failed for kernel args

kernel_args_malloc should be used after heap_init, or it will failed
when we new some region instance.

Change-Id: I457057b1e0ff6d4def9e101485e38fec1848d8de
Signed-off-by: Han Pengfei <[email protected]>
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3912
Reviewed-by: Alex von Gluck IV <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

src/system/boot/platform/efi/dtb.cpp

@@ -21,6 +21,10 @@
 #define ERROR(x...) dprintf("efi/fdt: " x)
 
 
+static void* sDtbTable = NULL;
+static uint32 sDtbSize = 0;
+
+
 static bool
 fdt_valid(void* fdt, uint32* size)
 {
@@ -56,16 +60,27 @@ dtb_init()
 		if (!fdt_valid(dtbPtr, &fdtSize)) {
 			ERROR("Invalid FDT from UEFI table %d\n", i);
 			break;
+		} else {
+			INFO("Valid FDT from UEFI table %d (%d)\n", i, fdtSize);
+
+			sDtbTable = dtbPtr;
+			sDtbSize = fdtSize;
+			break;
 		}
+	}
+}
 
-		INFO("Valid FDT from UEFI table %d (%d)\n", i, fdtSize);
 
-		// pack into proper location if the architecture cares
+void
+dtb_set_kernel_args()
+{
+	// pack into proper location if the architecture cares
+	if (sDtbTable != NULL) {
 		#ifdef __ARM__
-		gKernelArgs.arch_args.fdt = kernel_args_malloc(fdtSize);
+		gKernelArgs.arch_args.fdt = kernel_args_malloc(sDtbSize);
-		if (gKernelArgs.arch_args.fdt != NULL) {
+		if (gKernelArgs.arch_args.fdt != NULL)
-			memcpy(gKernelArgs.arch_args.fdt, dtbPtr, fdtSize);
+			memcpy(gKernelArgs.arch_args.fdt, sDtbTable, sDtbSize);
-		} else
+		else
 			ERROR("unable to malloc for fdt!\n");
 		#endif
 	}

src/system/boot/platform/efi/dtb.h

@@ -13,6 +13,7 @@
 
 
 extern void dtb_init();
+extern void dtb_set_kernel_args();
 
 
 #endif /* !_ASSEMBLER */

src/system/boot/platform/efi/start.cpp

@@ -146,6 +146,7 @@ extern "C" void
 platform_start_kernel(void)
 {
 	smp_init_other_cpus();
+	dtb_set_kernel_args();
 
 	addr_t kernelEntry = get_kernel_entry();