@@ -1790,6 +1790,17 @@ config ARM_APPENDED_DTB
(dtb) appended to zImage
(e.g. cat zImage <filename>.dtb > zImage_w_dtb).
+config ARM_ATAG_DTB_COMPAT
+ bool "Supplement the appended DTB with traditional ATAG information"
+ depends on ARM_APPENDED_DTB
+ help
+ Some old bootloaders can't be updated to a DTB capable one, yet
+ they provide ATAGs with memory configuration, the ramdisk address,
+ the kernel cmdline string, etc. To allow a device tree enabled
+ kernel to be used with such bootloaders, this option allows
+ zImage to extract the information from the ATAG list and store it
+ at run time into the appended DTB.
+
config CMDLINE
string "Default kernel command string"
default ""
@@ -5,3 +5,12 @@ piggy.lzo
piggy.lzma
vmlinux
vmlinux.lds
+
+# borrowed libfdt files
+fdt.c
+fdt.h
+fdt_ro.c
+fdt_rw.c
+fdt_wip.c
+libfdt.h
+libfdt_internal.h
@@ -89,19 +89,36 @@ suffix_$(CONFIG_KERNEL_GZIP) = gzip
suffix_$(CONFIG_KERNEL_LZO) = lzo
suffix_$(CONFIG_KERNEL_LZMA) = lzma
+# libfdt files for the ATAG compatibility mode
+
+libfdt := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c
+libfdt_hdrs := fdt.h libfdt.h libfdt_internal.h
+
+libfdt_objs := $(addsuffix .o, $(basename $(libfdt)))
+
+$(addprefix $(obj)/,$(libfdt) $(libfdt_hdrs)): $(obj)/%: $(srctree)/scripts/dtc/libfdt/%
+ $(call if_changed,shipped)
+
+$(addprefix $(obj)/,$(libfdt_objs) atags_to_fdt.o): \
+ $(addprefix $(obj)/,$(libfdt_hdrs))
+
+ifeq ($(CONFIG_ARM_ATAG_DTB_COMPAT),y)
+OBJS += $(libfdt_objs) atags_to_fdt.o
+endif
+
targets := vmlinux vmlinux.lds \
piggy.$(suffix_y) piggy.$(suffix_y).o \
font.o font.c head.o misc.o $(OBJS)
# Make sure files are removed during clean
-extra-y += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S
+extra-y += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S $(libfdt) $(libfdt_hdrs)
ifeq ($(CONFIG_FUNCTION_TRACER),y)
ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
endif
-ccflags-y := -fpic -fno-builtin
+ccflags-y := -fpic -fno-builtin -I$(src)
asflags-y := -Wa,-march=all
# Supply kernel BSS size to the decompressor via a linker symbol.
@@ -124,7 +141,7 @@ LDFLAGS_vmlinux += -X
LDFLAGS_vmlinux += -T
# For __aeabi_uidivmod
-lib1funcs = $(obj)/lib1funcs.o
+lib1funcs = $(obj)/lib1funcs.o $(obj)/../../lib/lib.a
$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE
$(call cmd,shipped)
new file mode 100644
@@ -0,0 +1,97 @@
+#include <asm/setup.h>
+#include <libfdt.h>
+
+static int node_offset(void *fdt, const char *node_path)
+{
+ int offset = fdt_path_offset(fdt, node_path);
+ if (offset == -FDT_ERR_NOTFOUND)
+ offset = fdt_add_subnode(fdt, 0, node_path);
+ return offset;
+}
+
+static int setprop(void *fdt, const char *node_path, const char *property,
+ uint32_t *val_array, int size)
+{
+ int offset = node_offset(fdt, node_path);
+ if (offset < 0)
+ return offset;
+ return fdt_setprop(fdt, offset, property, val_array, size);
+}
+
+static int setprop_string(void *fdt, const char *node_path,
+ const char *property, const char *string)
+{
+ int offset = node_offset(fdt, node_path);
+ if (offset < 0)
+ return offset;
+ return fdt_setprop_string(fdt, offset, property, string);
+}
+
+static int setprop_cell(void *fdt, const char *node_path,
+ const char *property, uint32_t val)
+{
+ int offset = node_offset(fdt, node_path);
+ if (offset < 0)
+ return offset;
+ return fdt_setprop_cell(fdt, offset, property, val);
+}
+
+/*
+ * Convert and fold provided ATAGs into the provided FDT.
+ *
+ * REturn values:
+ * = 0 -> pretend success
+ * = 1 -> bad ATAG (may retry with another possible ATAG pointer)
+ * < 0 -> error from libfdt
+ */
+int atags_to_fdt(void *atag_list, void *fdt, int total_space)
+{
+ struct tag *atag = atag_list;
+ uint32_t mem_reg_property[16];
+ int memcount = 0;
+ int ret;
+
+ /* make sure we've got an aligned pointer */
+ if ((u32)atag_list & 0x3)
+ return 1;
+
+ /* if we get a DTB here we're done already */
+ if (*(u32 *)atag_list == fdt32_to_cpu(FDT_MAGIC))
+ return 0;
+
+ /* validate the ATAG */
+ if (atag->hdr.tag != ATAG_CORE ||
+ (atag->hdr.size != tag_size(tag_core) &&
+ atag->hdr.size != 2))
+ return 1;
+
+ /* let's give it all the room it could need */
+ ret = fdt_open_into(fdt, fdt, total_space);
+ if (ret < 0)
+ return ret;
+
+ for_each_tag(atag, atag_list) {
+ if (atag->hdr.tag == ATAG_CMDLINE) {
+ setprop_string(fdt, "/chosen", "bootargs",
+ atag->u.cmdline.cmdline);
+ } else if (atag->hdr.tag == ATAG_MEM) {
+ if (memcount >= sizeof(mem_reg_property)/sizeof(uint32_t))
+ continue;
+ mem_reg_property[memcount++] = cpu_to_fdt32(atag->u.mem.start);
+ mem_reg_property[memcount++] = cpu_to_fdt32(atag->u.mem.size);
+ } else if (atag->hdr.tag == ATAG_INITRD2) {
+ uint32_t initrd_start, initrd_size;
+ initrd_start = atag->u.initrd.start;
+ initrd_size = atag->u.initrd.size;
+ setprop_cell(fdt, "/chosen", "linux,initrd-start",
+ initrd_start);
+ setprop_cell(fdt, "/chosen", "linux,initrd-end",
+ initrd_start + initrd_size);
+ }
+ }
+
+ if (memcount)
+ setprop(fdt, "/memory", "reg", mem_reg_property, 4*memcount);
+
+ return fdt_pack(fdt);
+}
@@ -246,6 +246,38 @@ restart: adr r0, LC0
cmp lr, r1
bne dtb_check_done @ not found
+#ifdef CONFIG_ARM_ATAG_DTB_COMPAT
+ /*
+ * OK... Let's do some funky business here.
+ * If we do have a DTB appended to zImage, and we do have
+ * an ATAG list around, we want the later to be translated
+ * and folded into the former here. To be on the safe side,
+ * let's temporarily move the stack away into the malloc
+ * area. No GOT fixup has occurred yet, but none of the
+ * code we're about to call uses any global variable.
+ */
+ add sp, sp, #0x10000
+ stmfd sp!, {r0-r3, ip, lr}
+ mov r0, r8
+ mov r1, r6
+ sub r2, sp, r6
+ bl atags_to_fdt
+
+ /*
+ * If returned value is 1, there is no ATAG at the location
+ * pointed by r8. Try the typical 0x100 offset from start
+ * of RAM and hope for the best.
+ */
+ cmp r0, #1
+ sub r0, r4, #(TEXT_OFFSET - 0x100)
+ mov r1, r6
+ sub r2, sp, r6
+ blne atags_to_fdt
+
+ ldmfd sp!, {r0-r3, ip, lr}
+ sub sp, sp, #0x10000
+#endif
+
mov r8, r6 @ use the appended device tree
/*
new file mode 100644
@@ -0,0 +1,15 @@
+#ifndef _ARM_LIBFDT_ENV_H
+#define _ARM_LIBFDT_ENV_H
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <asm/byteorder.h>
+
+#define fdt16_to_cpu(x) be16_to_cpu(x)
+#define cpu_to_fdt16(x) cpu_to_be16(x)
+#define fdt32_to_cpu(x) be32_to_cpu(x)
+#define cpu_to_fdt32(x) cpu_to_be32(x)
+#define fdt64_to_cpu(x) be64_to_cpu(x)
+#define cpu_to_fdt64(x) cpu_to_be64(x)
+
+#endif
@@ -136,6 +136,58 @@ void *memcpy(void *__dest, __const void *__src, size_t __n)
return __dest;
}
+void *memmove(void *__dest, __const void *__src, size_t __n)
+{
+ unsigned char *d = __dest;
+ const unsigned char *s = __src;
+
+ if (__dest == __src)
+ return __dest;
+
+ if (__dest < __src)
+ return memcpy(__dest, __src, __n);
+
+ while (__n--)
+ d[__n] = s[__n];
+
+ return __dest;
+}
+
+size_t strlen(const char *s)
+{
+ const char *sc;
+
+ for (sc = s; *sc != '\0'; ++sc)
+ /* nothing */;
+ return sc - s;
+}
+
+int memcmp(const void *cs, const void *ct, size_t count)
+{
+ const unsigned char *su1, *su2;
+ int res = 0;
+
+ for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
+ if ((res = *su1 - *su2) != 0)
+ break;
+ return res;
+}
+
+int strcmp(const char *cs, const char *ct)
+{
+ unsigned char c1, c2;
+
+ while (1) {
+ c1 = *cs++;
+ c2 = *ct++;
+ if (c1 != c2)
+ return c1 < c2 ? -1 : 1;
+ if (!c1)
+ break;
+ }
+ return 0;
+}
+
/*
* gzip declarations
*/