diff options
| -rw-r--r-- | arch/arm/Kconfig | 19 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/.gitignore | 9 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/Makefile | 26 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/atags_to_fdt.c | 97 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/head.S | 121 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/libfdt_env.h | 15 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/misc.c | 52 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/vmlinux.lds.in | 3 |
8 files changed, 332 insertions, 10 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index a1c3ea972d5..f38e275bea3 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1752,6 +1752,25 @@ config ZBOOT_ROM_MMCIF which in turn loads the rest the kernel image to RAM using the MMCIF hardware block. +config ARM_APPENDED_DTB + bool "Use appended device tree blob to zImage" + depends on OF && !ZBOOT_ROM + help + With this option, the boot code will look for a device tree binary + (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 "" diff --git a/arch/arm/boot/compressed/.gitignore b/arch/arm/boot/compressed/.gitignore index c6028967d33..e0936a14851 100644 --- a/arch/arm/boot/compressed/.gitignore +++ b/arch/arm/boot/compressed/.gitignore @@ -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 diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 23aad072230..4b94995fc47 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -83,21 +83,41 @@ 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. +KBSS_SZ = $(shell size $(obj)/../../../../vmlinux | awk 'END{print $$3}') +LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ) # Supply ZRELADDR to the decompressor via a linker symbol. ifneq ($(CONFIG_AUTO_ZRELADDR),y) LDFLAGS_vmlinux += --defsym zreladdr=$(ZRELADDR) @@ -115,7 +135,7 @@ 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) diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c new file mode 100644 index 00000000000..d79afd7300b --- /dev/null +++ b/arch/arm/boot/compressed/atags_to_fdt.c @@ -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); +} diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 940b2017810..5a07162568f 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -216,6 +216,103 @@ restart: adr r0, LC0 mov r10, r6 #endif + mov r5, #0 @ init dtb size to 0 +#ifdef CONFIG_ARM_APPENDED_DTB +/* + * r0 = delta + * r2 = BSS start + * r3 = BSS end + * r4 = final kernel address + * r5 = appended dtb size (still unknown) + * r6 = _edata + * r7 = architecture ID + * r8 = atags/device tree pointer + * r9 = size of decompressed image + * r10 = end of this image, including bss/stack/malloc space if non XIP + * r11 = GOT start + * r12 = GOT end + * sp = stack pointer + * + * if there are device trees (dtb) appended to zImage, advance r10 so that the + * dtb data will get relocated along with the kernel if necessary. + */ + + ldr lr, [r6, #0] +#ifndef __ARMEB__ + ldr r1, =0xedfe0dd0 @ sig is 0xd00dfeed big endian +#else + ldr r1, =0xd00dfeed +#endif + 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 + + /* + * Make sure that the DTB doesn't end up in the final + * kernel's .bss area. To do so, we adjust the decompressed + * kernel size to compensate if that .bss size is larger + * than the relocated code. + */ + ldr r5, =_kernel_bss_size + adr r1, wont_overwrite + sub r1, r6, r1 + subs r1, r5, r1 + addhi r9, r9, r1 + + /* Get the dtb's size */ + ldr r5, [r6, #4] +#ifndef __ARMEB__ + /* convert r5 (dtb size) to little endian */ + eor r1, r5, r5, ror #16 + bic r1, r1, #0x00ff0000 + mov r5, r5, ror #8 + eor r5, r5, r1, lsr #8 +#endif + + /* preserve 64-bit alignment */ + add r5, r5, #7 + bic r5, r5, #7 + + /* relocate some pointers past the appended dtb */ + add r6, r6, r5 + add r10, r10, r5 + add sp, sp, r5 +dtb_check_done: +#endif + /* * Check to see if we will overwrite ourselves. * r4 = final kernel address @@ -223,15 +320,14 @@ restart: adr r0, LC0 * r10 = end of this image, including bss/stack/malloc space if non XIP * We basically want: * r4 - 16k page directory >= r10 -> OK - * r4 + image length <= current position (pc) -> OK + * r4 + image length <= address of wont_overwrite -> OK */ add r10, r10, #16384 cmp r4, r10 bhs wont_overwrite add r10, r4, r9 - ARM( cmp r10, pc ) - THUMB( mov lr, pc ) - THUMB( cmp r10, lr ) + adr r9, wont_overwrite + cmp r10, r9 bls wont_overwrite /* @@ -285,14 +381,16 @@ wont_overwrite: * r2 = BSS start * r3 = BSS end * r4 = kernel execution address + * r5 = appended dtb size (0 if not present) * r7 = architecture ID * r8 = atags pointer * r11 = GOT start * r12 = GOT end * sp = stack pointer */ - teq r0, #0 + orrs r1, r0, r5 beq not_relocated + add r11, r11, r0 add r12, r12, r0 @@ -307,12 +405,21 @@ wont_overwrite: /* * Relocate all entries in the GOT table. + * Bump bss entries to _edata + dtb size */ 1: ldr r1, [r11, #0] @ relocate entries in the GOT - add r1, r1, r0 @ table. This fixes up the - str r1, [r11], #4 @ C references. + add r1, r1, r0 @ This fixes up C references + cmp r1, r2 @ if entry >= bss_start && + cmphs r3, r1 @ bss_end > entry + addhi r1, r1, r5 @ entry += dtb size + str r1, [r11], #4 @ next entry cmp r11, r12 blo 1b + + /* bump our bss pointers too */ + add r2, r2, r5 + add r3, r3, r5 + #else /* diff --git a/arch/arm/boot/compressed/libfdt_env.h b/arch/arm/boot/compressed/libfdt_env.h new file mode 100644 index 00000000000..1f4e71876b0 --- /dev/null +++ b/arch/arm/boot/compressed/libfdt_env.h @@ -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 diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c index 832d37236c5..16c98d8c28a 100644 --- a/arch/arm/boot/compressed/misc.c +++ b/arch/arm/boot/compressed/misc.c @@ -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 */ diff --git a/arch/arm/boot/compressed/vmlinux.lds.in b/arch/arm/boot/compressed/vmlinux.lds.in index ea80abe7884..6c02db134f2 100644 --- a/arch/arm/boot/compressed/vmlinux.lds.in +++ b/arch/arm/boot/compressed/vmlinux.lds.in @@ -47,6 +47,9 @@ SECTIONS .got : { *(.got) } _got_end = .; .got.plt : { *(.got.plt) } + + /* ensure the zImage file size is always a multiple of 64 bits */ + .pad : { BYTE(0); . = ALIGN(8); } _edata = .; . = BSS_START; |