Add FDT support to loader.efi. This will be used on arm and arm64.

Differential Revision:	https://reviews.freebsd.org/D2219

sys/boot/efi/Makefile

@@ -1,7 +1,15 @@
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 SUBDIR=		libefi
 
+.if ${TARGET_CPUARCH} == "aarch64" || ${TARGET_CPUARCH} == "arm"
+.if ${MK_FDT} != "no"
+SUBDIR+=	fdt
+.endif
+.endif
+
 .if ${MACHINE_CPUARCH} == "amd64"
 SUBDIR+=	loader boot1
 .endif

sys/boot/efi/loader/Makefile

@@ -42,6 +42,15 @@ CFLAGS+=	-I${.CURDIR}/../../ficl/${MACHINE_CPUARCH}
 LIBFICL=	${.OBJDIR}/../../ficl/libficl.a
 .endif
 
+LOADER_FDT_SUPPORT?=	no
+.if ${MK_FDT} != "no" && ${LOADER_FDT_SUPPORT} != "no"
+CFLAGS+=	-I${.CURDIR}/../../fdt
+CFLAGS+=	-I${.OBJDIR}/../../fdt
+CFLAGS+=	-DLOADER_FDT_SUPPORT
+LIBEFI_FDT=	${.OBJDIR}/../../efi/fdt/libefi_fdt.a
+LIBFDT=		${.OBJDIR}/../../fdt/libfdt.a
+.endif
+
 # Include bcache code.
 HAVE_BCACHE=    yes
 
@@ -88,8 +97,9 @@ loader.efi: loader.sym
 
 LIBEFI=		${.OBJDIR}/../libefi/libefi.a
 
-DPADD=		${LIBFICL} ${LIBEFI} ${LIBSTAND} ${LDSCRIPT}
+DPADD=		${LIBFICL} ${LIBEFI} ${LIBFDT} ${LIBEFI_FDT} ${LIBSTAND} \
-LDADD=		${LIBFICL} ${LIBEFI} ${LIBSTAND}
+		${LDSCRIPT}
+LDADD=		${LIBFICL} ${LIBEFI} ${LIBFDT} ${LIBEFI_FDT} ${LIBSTAND}
 
 .endif # ${COMPILER_TYPE} != "gcc"
 

sys/boot/efi/loader/bootinfo.c

@@ -51,6 +51,10 @@ __FBSDID("$FreeBSD$");
 #include "framebuffer.h"
 #endif
 
+#if defined(LOADER_FDT_SUPPORT)
+#include <fdt_platform.h>
+#endif
+
 UINTN efi_mapkey;
 
 static const char howto_switches[] = "aCdrgDmphsv";
@@ -324,6 +328,10 @@ bi_load(char *args, vm_offset_t *modulep, vm_offset_t *kernendp)
 	vm_offset_t size;
 	char *rootdevname;
 	int howto;
+#if defined(LOADER_FDT_SUPPORT)
+	vm_offset_t dtbp;
+	int dtb_size;
+#endif
 
 	howto = bi_getboothowto(args);
 
@@ -358,6 +366,16 @@ bi_load(char *args, vm_offset_t *modulep, vm_offset_t *kernendp)
 	/* Pad to a page boundary. */
 	addr = roundup(addr, PAGE_SIZE);
 
+#if defined(LOADER_FDT_SUPPORT)
+	/* Handle device tree blob */
+	dtbp = addr;
+	dtb_size = fdt_copy(addr);
+		
+	/* Pad to a page boundary */
+	if (dtb_size)
+		addr += roundup(dtb_size, PAGE_SIZE);
+#endif
+
 	kfp = file_findfile(NULL, "elf kernel");
 	if (kfp == NULL)
 		kfp = file_findfile(NULL, "elf64 kernel");
@@ -366,6 +384,13 @@ bi_load(char *args, vm_offset_t *modulep, vm_offset_t *kernendp)
 	kernend = 0;	/* fill it in later */
 	file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
 	file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
+#if defined(LOADER_FDT_SUPPORT)
+	if (dtb_size)
+		file_addmetadata(kfp, MODINFOMD_DTBP, sizeof dtbp, &dtbp);
+	else
+		pager_output("WARNING! Trying to fire up the kernel, but no "
+		    "device tree blob found!\n");
+#endif
 	file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
 
 	bi_load_efi_data(kfp);

sys/boot/efi/loader/main.c

@@ -387,3 +387,22 @@ command_nvram(int argc, char *argv[])
 
 	return (CMD_OK);
 }
+
+#ifdef LOADER_FDT_SUPPORT
+extern int command_fdt_internal(int argc, char *argv[]);
+
+/*
+ * Since proper fdt command handling function is defined in fdt_loader_cmd.c,
+ * and declaring it as extern is in contradiction with COMMAND_SET() macro
+ * (which uses static pointer), we're defining wrapper function, which
+ * calls the proper fdt handling routine.
+ */
+static int
+command_fdt(int argc, char *argv[])
+{
+
+	return (command_fdt_internal(argc, argv));
+}
+
+COMMAND_SET(fdt, "fdt", "flattened device tree handling", command_fdt);
+#endif