* [RFC 0/2] Appended Device Tree
@ 2011-01-26 21:22 John Bonesio
2011-01-26 21:23 ` [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage John Bonesio
2011-01-26 21:23 ` [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree John Bonesio
0 siblings, 2 replies; 6+ messages in thread
From: John Bonesio @ 2011-01-26 21:22 UTC (permalink / raw)
To: linux-arm-kernel
This not intended to be merged. This is a request for comments on the approach
being taken.
The following series implements a prototype/proof of concept for allowing a
device-tree binary (dtb) to be appended to the end of zImage. The dtb can be
appended with a command like:
cat zImage myboard.dtb > zImage_w_dtb.
The purpose is to allow a single kernel to be built for multiple boards/systems
and allow a simple process to apply the right device tree right before the
kernel image is written into flash. This way the system that applies the
device tree doesn't have to have the full gnu compiler set installed.
The old behavior has not changed. If a dtb is not appended, the kernel will
still boot as expected.
The frst patch detects if a dtb is present at the end of the zImage and uses
it, if present. The second patch merges in a couple of key atags, if present,
into the appended device-tree, if found.
With the new kernel config option enabled, this patch adds 11400 bytes to
zImage. The kernel code itself doesn't change size.
The first patch in this series adds 96 bytes to zImage.
The second patch in this series adds 11304 bytes to zImage.
These numbers vary depending on the kernel version, probably due to alignment requirements.
---
John Bonesio (2):
ARM:boot:device tree: Allow the device tree binary to be appended to zImage
ARM:boot:device tree: Merge specific atags into the device tree
arch/arm/Kconfig | 7 ++++
arch/arm/boot/compressed/Makefile | 31 ++++++++++++++++---
arch/arm/boot/compressed/atags.c | 50 +++++++++++++++++++++++++++++++
arch/arm/boot/compressed/head.S | 59 ++++++++++++++++++++++++++++++++++++-
arch/arm/boot/compressed/misc.c | 58 +++++++++++++++++++++++++++++++++++-
5 files changed, 196 insertions(+), 9 deletions(-)
create mode 100644 arch/arm/boot/compressed/atags.c
--
Signature
^ permalink raw reply [flat|nested] 6+ messages in thread* [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage 2011-01-26 21:22 [RFC 0/2] Appended Device Tree John Bonesio @ 2011-01-26 21:23 ` John Bonesio 2011-02-04 4:41 ` Nicolas Pitre 2011-01-26 21:23 ` [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree John Bonesio 1 sibling, 1 reply; 6+ messages in thread From: John Bonesio @ 2011-01-26 21:23 UTC (permalink / raw) To: linux-arm-kernel This patch provides the ability to boot using a device tree that is appended to the raw binary zImage (e.g. cat zImage <filename>.dtb > zImage_w_dtb). Constraints: 1) A maximum 16k device tree binary is copied to memory at 0x0. If the device tree is bigger than 16k, the kernel will probably fail ungracefully - unless there is a device tree already embedded in the zImage. Signed-off-by: John Bonesio <bones@secretlab.ca> Acked-by: Grant Likely <grant.likely@secretlab.ca> --- arch/arm/Kconfig | 7 +++++ arch/arm/boot/compressed/head.S | 52 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 57 insertions(+), 2 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index d8a330f..e63a441 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1593,6 +1593,13 @@ config USE_OF help Include support for flattened device tree machine descriptions. +config ARM_APPENDED_DTB + bool "Use appended device tree blob" if OF + default n + help + With this option, the boot code will look for a dtb bianry + appended to zImage. + # Compressed boot loader in ROM. Yes, we really want to ask about # TEXT and BSS so we preserve their values in the config files. config ZBOOT_ROM_TEXT diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 7193884..db860b3 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -138,7 +138,7 @@ start: b 1f .word 0x016f2818 @ Magic numbers to help the loader .word start @ absolute load/run zImage address - .word _edata @ zImage end address +DTB: .word _edata @ zImage end address THUMB( .thumb ) 1: mov r7, r1 @ save architecture ID mov r8, r2 @ save atags pointer @@ -173,6 +173,9 @@ not_angel: * by the linker here, but it should preserve r7, r8, and r9. */ + /* Check if there is an appended device tree binary */ + ldr r10, DTB @ get the address of _dtb + .text adr r0, LC0 ldmia r0, {r1, r2, r3, r5, r6, r11, ip} @@ -196,10 +199,12 @@ not_angel: * up various pointers: * r5 - zImage base address (_start) * r6 - size of decompressed image + * r10 - zImage end * r11 - GOT start * ip - GOT end */ add r5, r5, r0 + add r10, r10, r0 add r11, r11, r0 add ip, ip, r0 @@ -215,6 +220,7 @@ not_angel: add r3, r3, r0 add sp, sp, r0 + /* * Relocate all entries in the GOT table. */ @@ -238,7 +244,49 @@ not_angel: blo 1b #endif -not_relocated: mov r0, #0 +not_relocated: +#ifdef CONFIG_ARM_APPENDED_DTB + /* + * Check if there is an appended device tree binary, by testing + * for the device tree magic signature + * + * An appended device tree will be at the end of the zImage + */ + ldr r1, [r10, #0] + ldr r9, =0xedfe0dd0 @ sig is 0xdoodfeed stored big endian + cmp r1, r9 + bne keep_atags + + /* copy the device tree binary to 0x0 */ + ldr r9, [r10, #4] @ device tree size + + /* convert r9 (dtb size) to little endian */ + eor r1, r9, r9, ror #16 + bic r1, r1, #0x00ff0000 + mov r9, r9, ror #8 + eor r9, r9, r1, lsr #8 + + /* make sure the device tree isn't too big */ + mov r0, #16384 + cmp r9, r0 + bhi keep_atags + + mov r0, r2 + mov r1, #0x0 + add r9, r1 @ size to address from target location +1: + .rept 4 + ldmia r0!, {r10} @ relocate device tree + stmia r1!, {r10} + .endr + cmp r1, r9 + blo 1b + mov r8, #0x0 + +keep_atags: +#endif + +__not_relocated: mov r0, #0 1: str r0, [r2], #4 @ clear bss str r0, [r2], #4 str r0, [r2], #4 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage 2011-01-26 21:23 ` [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage John Bonesio @ 2011-02-04 4:41 ` Nicolas Pitre 0 siblings, 0 replies; 6+ messages in thread From: Nicolas Pitre @ 2011-02-04 4:41 UTC (permalink / raw) To: linux-arm-kernel On Wed, 26 Jan 2011, John Bonesio wrote: > This patch provides the ability to boot using a device tree that is appended > to the raw binary zImage (e.g. cat zImage <filename>.dtb > zImage_w_dtb). > > Constraints: > 1) A maximum 16k device tree binary is copied to memory at 0x0. If the device > tree is bigger than 16k, the kernel will probably fail ungracefully - unless > there is a device tree already embedded in the zImage. This will ungracefully fail on targets where physical memory is not located at 0x0. And this is not an uncommon situation on ARM. > Signed-off-by: John Bonesio <bones@secretlab.ca> > Acked-by: Grant Likely <grant.likely@secretlab.ca> NAK. This is not the way to go about this. First of all, there is a bit of a misdesign in the kernel decompressor. It currently verifies that the decompressed data destination doesn't conflict with the decompressor itself. If there is indeed an overlap, then the decompressor stores the decompressed data above itself and relocates that data back to its final location when it is done decompressing. Instead, the decompressor should move _itself_ out of the way rather than moving the decompressed data, as that would make for a smaller copy. I'll try to have a look at that part if no one beats me to it. Once this is "fixed", then all you'll have to do is to simply pass the (possibly relocated with the decompressor) address of the dtb data into r2 without copying it anywhere else. That's it, and no 16KB limit. Nicolas ^ permalink raw reply [flat|nested] 6+ messages in thread
* [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree 2011-01-26 21:22 [RFC 0/2] Appended Device Tree John Bonesio 2011-01-26 21:23 ` [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage John Bonesio @ 2011-01-26 21:23 ` John Bonesio 2011-02-04 4:44 ` Nicolas Pitre 1 sibling, 1 reply; 6+ messages in thread From: John Bonesio @ 2011-01-26 21:23 UTC (permalink / raw) To: linux-arm-kernel This patch is to merge in key atags into the appended device tree. An appended device tree is where the zImage has a dtb binary appended at the end of it. The boot code looks for an appended device tree, then looks for a few key atags passed in by the bootloader. The bootargs and memory size settings, if they exist, override existing values in the appended device tree. If these values don't currently exist in the appended device tree, they are added. Signed-off-by: John Bonesio <bones@secretlab.ca> Acked-by: Grant Likely <grant.likely@secretlab.ca> --- arch/arm/boot/compressed/Makefile | 31 +++++++++++++++++--- arch/arm/boot/compressed/atags.c | 50 ++++++++++++++++++++++++++++++++ arch/arm/boot/compressed/head.S | 7 ++++ arch/arm/boot/compressed/misc.c | 58 ++++++++++++++++++++++++++++++++++++- 4 files changed, 139 insertions(+), 7 deletions(-) create mode 100644 arch/arm/boot/compressed/atags.c diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 0a8f748..7978a39 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -49,6 +49,10 @@ ifeq ($(CONFIG_ARCH_SHMOBILE),y) OBJS += head-shmobile.o endif +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) +OBJS += atags.o libfdt.a +endif + # # We now have a PIC decompressor implementation. Decompressors running # from RAM should not define ZTEXTADDR. Decompressors running directly @@ -80,7 +84,9 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS) KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) endif -EXTRA_CFLAGS := -fpic -fno-builtin +fdttree := $(srctree)/scripts/dtc/libfdt + +EXTRA_CFLAGS := -fpic -fno-builtin -I$(fdttree) -I$(obj) EXTRA_AFLAGS := -Wa,-march=all # Supply ZRELADDR to the decompressor via a linker symbol. @@ -100,13 +106,28 @@ LDFLAGS_vmlinux += -X LDFLAGS_vmlinux += -T # For __aeabi_uidivmod -lib1funcs = $(obj)/lib1funcs.o +libfuncs = $(obj)/lib1funcs.o -$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE - $(call cmd,shipped) +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) +# For memchr, memmove, etc +libfuncs += $(obj)/memchr.o $(obj)/strchr.o $(obj)/memmove.o $(obj)/memzero.o +endif + + +libfdtheader := $(fdttree)/fdt.h $(fdttree)/libfdt.h $(fdttree)/libfdt_internal.h +libfdtobj := $(obj)/fdt.o $(obj)/fdt_ro.o $(obj)/fdt_wip.o $(obj)/fdt_sw.o $(obj)/fdt_rw.o $(obj)/fdt_strerror.o + +$(libfdtobj): $(obj)/%.o: $(srctree)/scripts/dtc/libfdt/%.c $(libfdtheader) + $(call cmd_cc_o_c) + +$(obj)/libfdt.a: $(libfdtobj) + $(AR) rcs $@ $^ + +$(libfuncs): $(obj)/%.o: $(srctree)/arch/$(SRCARCH)/lib/%.S + $(call cmd_as_o_S) $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ - $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE + $(addprefix $(obj)/, $(OBJS)) $(libfuncs) FORCE $(call if_changed,ld) @: diff --git a/arch/arm/boot/compressed/atags.c b/arch/arm/boot/compressed/atags.c new file mode 100644 index 0000000..e37d8de --- /dev/null +++ b/arch/arm/boot/compressed/atags.c @@ -0,0 +1,50 @@ +#include <stddef.h> +#include <asm/byteorder.h> +#include <asm/setup.h> +#include <fdt.h> +#include <libfdt.h> + + +int dt_setprop(void *fdt, const char *node_path, const char *property, + uint32_t *val_array, int size) +{ + int offset; + + offset = fdt_path_offset(fdt, node_path); + if (offset < 0) + return offset; + + return fdt_setprop(fdt, offset, property, val_array, size); +} + +int dt_setprop_string(void *fdt, const char *node_path, + const char *property, const char *string) +{ + int offset; + + offset = fdt_path_offset(fdt, node_path); + if (offset < 0) + return offset; + + return fdt_setprop_string(fdt, offset, property, string); +} + +void dt_merge_atags(void *dt, void *ataglist) +{ + struct tag *atag = ataglist; + uint32_t mem_reg_property[2]; + + while (atag && atag->hdr.tag != 0) { + if (atag->hdr.tag == ATAG_CMDLINE) { + dt_setprop_string(dt, "/chosen", "bootargs", + atag->u.cmdline.cmdline); + } else if (atag->hdr.tag == ATAG_MEM) { + mem_reg_property[0] = cpu_to_fdt32(atag->u.mem.start); + mem_reg_property[1] = cpu_to_fdt32(atag->u.mem.size); + dt_setprop(dt, "/memory", "reg", mem_reg_property, + sizeof(mem_reg_property)); + } + atag = tag_next(atag); + } +} + diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index db860b3..09e659d 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -257,6 +257,13 @@ not_relocated: cmp r1, r9 bne keep_atags + /* Merge some of the atags into the device tree */ + push {r2, r3, r10, r11} + mov r0, r2 + mov r1, r8 + bl dt_merge_atags + pop {r2, r3, r10, r11} + /* copy the device tree binary to 0x0 */ ldr r9, [r10, #4] @ device tree size diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c index e653a6d..2d4da4c 100644 --- a/arch/arm/boot/compressed/misc.c +++ b/arch/arm/boot/compressed/misc.c @@ -29,7 +29,7 @@ unsigned int __machine_arch_type; #include <asm/unaligned.h> -static void putstr(const char *ptr); +void putstr(const char *ptr); extern void error(char *x); #include <mach/uncompress.h> @@ -100,7 +100,7 @@ static void icedcc_putc(int ch) #define putc(ch) icedcc_putc(ch) #endif -static void putstr(const char *ptr) +void putstr(const char *ptr) { char c; @@ -114,6 +114,60 @@ static void putstr(const char *ptr) } +#ifdef CONFIG_ARM_APPENDED_DTB +/** + * strlen - Find the length of a string + * @s: The string to be sized + */ +size_t strlen(const char *s) +{ + const char *sc; + + for (sc = s; *sc != '\0'; ++sc) + /* nothing */; + return sc - s; +} + +/** + * strcmp - Compare two strings + * @cs: One string + * @ct: Another string + */ +#undef strcmp +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; +} + +/** + * memcmp - Compare two areas of memory + * @cs: One area of memory + * @ct: Another area of memory + * @count: The size of the area. + */ +#undef memcmp +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; +} +#endif + void *memcpy(void *__dest, __const void *__src, size_t __n) { int i = 0; ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree 2011-01-26 21:23 ` [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree John Bonesio @ 2011-02-04 4:44 ` Nicolas Pitre 2011-02-04 4:59 ` Grant Likely 0 siblings, 1 reply; 6+ messages in thread From: Nicolas Pitre @ 2011-02-04 4:44 UTC (permalink / raw) To: linux-arm-kernel On Wed, 26 Jan 2011, John Bonesio wrote: > This patch is to merge in key atags into the appended device tree. An appended > device tree is where the zImage has a dtb binary appended at the end of it. The > boot code looks for an appended device tree, then looks for a few key atags > passed in by the bootloader. > > The bootargs and memory size settings, if they exist, override existing values > in the appended device tree. If these values don't currently exist in the > appended device tree, they are added. > > Signed-off-by: John Bonesio <bones@secretlab.ca> > Acked-by: Grant Likely <grant.likely@secretlab.ca> This is just for testing/evaluation purpose and not intended to be merged upstream at some point, right? > --- > > arch/arm/boot/compressed/Makefile | 31 +++++++++++++++++--- > arch/arm/boot/compressed/atags.c | 50 ++++++++++++++++++++++++++++++++ > arch/arm/boot/compressed/head.S | 7 ++++ > arch/arm/boot/compressed/misc.c | 58 ++++++++++++++++++++++++++++++++++++- > 4 files changed, 139 insertions(+), 7 deletions(-) > create mode 100644 arch/arm/boot/compressed/atags.c > > diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile > index 0a8f748..7978a39 100644 > --- a/arch/arm/boot/compressed/Makefile > +++ b/arch/arm/boot/compressed/Makefile > @@ -49,6 +49,10 @@ ifeq ($(CONFIG_ARCH_SHMOBILE),y) > OBJS += head-shmobile.o > endif > > +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) > +OBJS += atags.o libfdt.a > +endif > + > # > # We now have a PIC decompressor implementation. Decompressors running > # from RAM should not define ZTEXTADDR. Decompressors running directly > @@ -80,7 +84,9 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS) > KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) > endif > > -EXTRA_CFLAGS := -fpic -fno-builtin > +fdttree := $(srctree)/scripts/dtc/libfdt > + > +EXTRA_CFLAGS := -fpic -fno-builtin -I$(fdttree) -I$(obj) > EXTRA_AFLAGS := -Wa,-march=all > > # Supply ZRELADDR to the decompressor via a linker symbol. > @@ -100,13 +106,28 @@ LDFLAGS_vmlinux += -X > LDFLAGS_vmlinux += -T > > # For __aeabi_uidivmod > -lib1funcs = $(obj)/lib1funcs.o > +libfuncs = $(obj)/lib1funcs.o > > -$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE > - $(call cmd,shipped) > +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) > +# For memchr, memmove, etc > +libfuncs += $(obj)/memchr.o $(obj)/strchr.o $(obj)/memmove.o $(obj)/memzero.o > +endif > + > + > +libfdtheader := $(fdttree)/fdt.h $(fdttree)/libfdt.h $(fdttree)/libfdt_internal.h > +libfdtobj := $(obj)/fdt.o $(obj)/fdt_ro.o $(obj)/fdt_wip.o $(obj)/fdt_sw.o $(obj)/fdt_rw.o $(obj)/fdt_strerror.o > + > +$(libfdtobj): $(obj)/%.o: $(srctree)/scripts/dtc/libfdt/%.c $(libfdtheader) > + $(call cmd_cc_o_c) > + > +$(obj)/libfdt.a: $(libfdtobj) > + $(AR) rcs $@ $^ > + > +$(libfuncs): $(obj)/%.o: $(srctree)/arch/$(SRCARCH)/lib/%.S > + $(call cmd_as_o_S) > > $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ > - $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE > + $(addprefix $(obj)/, $(OBJS)) $(libfuncs) FORCE > $(call if_changed,ld) > @: > > diff --git a/arch/arm/boot/compressed/atags.c b/arch/arm/boot/compressed/atags.c > new file mode 100644 > index 0000000..e37d8de > --- /dev/null > +++ b/arch/arm/boot/compressed/atags.c > @@ -0,0 +1,50 @@ > +#include <stddef.h> > +#include <asm/byteorder.h> > +#include <asm/setup.h> > +#include <fdt.h> > +#include <libfdt.h> > + > + > +int dt_setprop(void *fdt, const char *node_path, const char *property, > + uint32_t *val_array, int size) > +{ > + int offset; > + > + offset = fdt_path_offset(fdt, node_path); > + if (offset < 0) > + return offset; > + > + return fdt_setprop(fdt, offset, property, val_array, size); > +} > + > +int dt_setprop_string(void *fdt, const char *node_path, > + const char *property, const char *string) > +{ > + int offset; > + > + offset = fdt_path_offset(fdt, node_path); > + if (offset < 0) > + return offset; > + > + return fdt_setprop_string(fdt, offset, property, string); > +} > + > +void dt_merge_atags(void *dt, void *ataglist) > +{ > + struct tag *atag = ataglist; > + uint32_t mem_reg_property[2]; > + > + while (atag && atag->hdr.tag != 0) { > + if (atag->hdr.tag == ATAG_CMDLINE) { > + dt_setprop_string(dt, "/chosen", "bootargs", > + atag->u.cmdline.cmdline); > + } else if (atag->hdr.tag == ATAG_MEM) { > + mem_reg_property[0] = cpu_to_fdt32(atag->u.mem.start); > + mem_reg_property[1] = cpu_to_fdt32(atag->u.mem.size); > + dt_setprop(dt, "/memory", "reg", mem_reg_property, > + sizeof(mem_reg_property)); > + } > + atag = tag_next(atag); > + } > +} > + > diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S > index db860b3..09e659d 100644 > --- a/arch/arm/boot/compressed/head.S > +++ b/arch/arm/boot/compressed/head.S > @@ -257,6 +257,13 @@ not_relocated: > cmp r1, r9 > bne keep_atags > > + /* Merge some of the atags into the device tree */ > + push {r2, r3, r10, r11} > + mov r0, r2 > + mov r1, r8 > + bl dt_merge_atags > + pop {r2, r3, r10, r11} > + > /* copy the device tree binary to 0x0 */ > ldr r9, [r10, #4] @ device tree size > > diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c > index e653a6d..2d4da4c 100644 > --- a/arch/arm/boot/compressed/misc.c > +++ b/arch/arm/boot/compressed/misc.c > @@ -29,7 +29,7 @@ unsigned int __machine_arch_type; > #include <asm/unaligned.h> > > > -static void putstr(const char *ptr); > +void putstr(const char *ptr); > extern void error(char *x); > > #include <mach/uncompress.h> > @@ -100,7 +100,7 @@ static void icedcc_putc(int ch) > #define putc(ch) icedcc_putc(ch) > #endif > > -static void putstr(const char *ptr) > +void putstr(const char *ptr) > { > char c; > > @@ -114,6 +114,60 @@ static void putstr(const char *ptr) > } > > > +#ifdef CONFIG_ARM_APPENDED_DTB > +/** > + * strlen - Find the length of a string > + * @s: The string to be sized > + */ > +size_t strlen(const char *s) > +{ > + const char *sc; > + > + for (sc = s; *sc != '\0'; ++sc) > + /* nothing */; > + return sc - s; > +} > + > +/** > + * strcmp - Compare two strings > + * @cs: One string > + * @ct: Another string > + */ > +#undef strcmp > +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; > +} > + > +/** > + * memcmp - Compare two areas of memory > + * @cs: One area of memory > + * @ct: Another area of memory > + * @count: The size of the area. > + */ > +#undef memcmp > +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; > +} > +#endif > + > void *memcpy(void *__dest, __const void *__src, size_t __n) > { > int i = 0; > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > ^ permalink raw reply [flat|nested] 6+ messages in thread
* [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree 2011-02-04 4:44 ` Nicolas Pitre @ 2011-02-04 4:59 ` Grant Likely 0 siblings, 0 replies; 6+ messages in thread From: Grant Likely @ 2011-02-04 4:59 UTC (permalink / raw) To: linux-arm-kernel On Feb 3, 2011 9:44 PM, "Nicolas Pitre" <nico@fluxnic.net> wrote: > > On Wed, 26 Jan 2011, John Bonesio wrote: > > > This patch is to merge in key atags into the appended device tree. An appended > > device tree is where the zImage has a dtb binary appended at the end of it. The > > boot code looks for an appended device tree, then looks for a few key atags > > passed in by the bootloader. > > > > The bootargs and memory size settings, if they exist, override existing values > > in the appended device tree. If these values don't currently exist in the > > appended device tree, they are added. > > > > Signed-off-by: John Bonesio <bones@secretlab.ca> > > Acked-by: Grant Likely <grant.likely@secretlab.ca> > > This is just for testing/evaluation purpose and not intended to be > merged upstream at some point, right? Correct. > > > --- > > > > arch/arm/boot/compressed/Makefile | 31 +++++++++++++++++--- > > arch/arm/boot/compressed/atags.c | 50 ++++++++++++++++++++++++++++++++ > > arch/arm/boot/compressed/head.S | 7 ++++ > > arch/arm/boot/compressed/misc.c | 58 ++++++++++++++++++++++++++++++++++++- > > 4 files changed, 139 insertions(+), 7 deletions(-) > > create mode 100644 arch/arm/boot/compressed/atags.c > > > > diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile > > index 0a8f748..7978a39 100644 > > --- a/arch/arm/boot/compressed/Makefile > > +++ b/arch/arm/boot/compressed/Makefile > > @@ -49,6 +49,10 @@ ifeq ($(CONFIG_ARCH_SHMOBILE),y) > > OBJS += head-shmobile.o > > endif > > > > +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) > > +OBJS += atags.o libfdt.a > > +endif > > + > > # > > # We now have a PIC decompressor implementation. Decompressors running > > # from RAM should not define ZTEXTADDR. Decompressors running directly > > @@ -80,7 +84,9 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS) > > KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) > > endif > > > > -EXTRA_CFLAGS := -fpic -fno-builtin > > +fdttree := $(srctree)/scripts/dtc/libfdt > > + > > +EXTRA_CFLAGS := -fpic -fno-builtin -I$(fdttree) -I$(obj) > > EXTRA_AFLAGS := -Wa,-march=all > > > > # Supply ZRELADDR to the decompressor via a linker symbol. > > @@ -100,13 +106,28 @@ LDFLAGS_vmlinux += -X > > LDFLAGS_vmlinux += -T > > > > # For __aeabi_uidivmod > > -lib1funcs = $(obj)/lib1funcs.o > > +libfuncs = $(obj)/lib1funcs.o > > > > -$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE > > - $(call cmd,shipped) > > +ifeq ($(CONFIG_ARM_APPENDED_DTB),y) > > +# For memchr, memmove, etc > > +libfuncs += $(obj)/memchr.o $(obj)/strchr.o $(obj)/memmove.o $(obj)/memzero.o > > +endif > > + > > + > > +libfdtheader := $(fdttree)/fdt.h $(fdttree)/libfdt.h $(fdttree)/libfdt_internal.h > > +libfdtobj := $(obj)/fdt.o $(obj)/fdt_ro.o $(obj)/fdt_wip.o $(obj)/fdt_sw.o $(obj)/fdt_rw.o $(obj)/fdt_strerror.o > > + > > +$(libfdtobj): $(obj)/%.o: $(srctree)/scripts/dtc/libfdt/%.c $(libfdtheader) > > + $(call cmd_cc_o_c) > > + > > +$(obj)/libfdt.a: $(libfdtobj) > > + $(AR) rcs $@ $^ > > + > > +$(libfuncs): $(obj)/%.o: $(srctree)/arch/$(SRCARCH)/lib/%.S > > + $(call cmd_as_o_S) > > > > $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ > > - $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE > > + $(addprefix $(obj)/, $(OBJS)) $(libfuncs) FORCE > > $(call if_changed,ld) > > @: > > > > diff --git a/arch/arm/boot/compressed/atags.c b/arch/arm/boot/compressed/atags.c > > new file mode 100644 > > index 0000000..e37d8de > > --- /dev/null > > +++ b/arch/arm/boot/compressed/atags.c > > @@ -0,0 +1,50 @@ > > +#include <stddef.h> > > +#include <asm/byteorder.h> > > +#include <asm/setup.h> > > +#include <fdt.h> > > +#include <libfdt.h> > > + > > + > > +int dt_setprop(void *fdt, const char *node_path, const char *property, > > + uint32_t *val_array, int size) > > +{ > > + int offset; > > + > > + offset = fdt_path_offset(fdt, node_path); > > + if (offset < 0) > > + return offset; > > + > > + return fdt_setprop(fdt, offset, property, val_array, size); > > +} > > + > > +int dt_setprop_string(void *fdt, const char *node_path, > > + const char *property, const char *string) > > +{ > > + int offset; > > + > > + offset = fdt_path_offset(fdt, node_path); > > + if (offset < 0) > > + return offset; > > + > > + return fdt_setprop_string(fdt, offset, property, string); > > +} > > + > > +void dt_merge_atags(void *dt, void *ataglist) > > +{ > > + struct tag *atag = ataglist; > > + uint32_t mem_reg_property[2]; > > + > > + while (atag && atag->hdr.tag != 0) { > > + if (atag->hdr.tag == ATAG_CMDLINE) { > > + dt_setprop_string(dt, "/chosen", "bootargs", > > + atag->u.cmdline.cmdline); > > + } else if (atag->hdr.tag == ATAG_MEM) { > > + mem_reg_property[0] = cpu_to_fdt32(atag->u.mem.start); > > + mem_reg_property[1] = cpu_to_fdt32(atag->u.mem.size); > > + dt_setprop(dt, "/memory", "reg", mem_reg_property, > > + sizeof(mem_reg_property)); > > + } > > + atag = tag_next(atag); > > + } > > +} > > + > > diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S > > index db860b3..09e659d 100644 > > --- a/arch/arm/boot/compressed/head.S > > +++ b/arch/arm/boot/compressed/head.S > > @@ -257,6 +257,13 @@ not_relocated: > > cmp r1, r9 > > bne keep_atags > > > > + /* Merge some of the atags into the device tree */ > > + push {r2, r3, r10, r11} > > + mov r0, r2 > > + mov r1, r8 > > + bl dt_merge_atags > > + pop {r2, r3, r10, r11} > > + > > /* copy the device tree binary to 0x0 */ > > ldr r9, [r10, #4] @ device tree size > > > > diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c > > index e653a6d..2d4da4c 100644 > > --- a/arch/arm/boot/compressed/misc.c > > +++ b/arch/arm/boot/compressed/misc.c > > @@ -29,7 +29,7 @@ unsigned int __machine_arch_type; > > #include <asm/unaligned.h> > > > > > > -static void putstr(const char *ptr); > > +void putstr(const char *ptr); > > extern void error(char *x); > > > > #include <mach/uncompress.h> > > @@ -100,7 +100,7 @@ static void icedcc_putc(int ch) > > #define putc(ch) icedcc_putc(ch) > > #endif > > > > -static void putstr(const char *ptr) > > +void putstr(const char *ptr) > > { > > char c; > > > > @@ -114,6 +114,60 @@ static void putstr(const char *ptr) > > } > > > > > > +#ifdef CONFIG_ARM_APPENDED_DTB > > +/** > > + * strlen - Find the length of a string > > + * @s: The string to be sized > > + */ > > +size_t strlen(const char *s) > > +{ > > + const char *sc; > > + > > + for (sc = s; *sc != '\0'; ++sc) > > + /* nothing */; > > + return sc - s; > > +} > > + > > +/** > > + * strcmp - Compare two strings > > + * @cs: One string > > + * @ct: Another string > > + */ > > +#undef strcmp > > +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; > > +} > > + > > +/** > > + * memcmp - Compare two areas of memory > > + * @cs: One area of memory > > + * @ct: Another area of memory > > + * @count: The size of the area. > > + */ > > +#undef memcmp > > +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; > > +} > > +#endif > > + > > void *memcpy(void *__dest, __const void *__src, size_t __n) > > { > > int i = 0; > > > > > > _______________________________________________ > > linux-arm-kernel mailing list > > linux-arm-kernel at lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20110203/60251662/attachment-0001.html> ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2011-02-04 4:59 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2011-01-26 21:22 [RFC 0/2] Appended Device Tree John Bonesio 2011-01-26 21:23 ` [RFC 1/2] ARM:boot:device tree: Allow the device tree binary to be appended to zImage John Bonesio 2011-02-04 4:41 ` Nicolas Pitre 2011-01-26 21:23 ` [RFC 2/2] ARM:boot:device tree: Merge specific atags into the device tree John Bonesio 2011-02-04 4:44 ` Nicolas Pitre 2011-02-04 4:59 ` Grant Likely
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