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 <[email protected]>
> Acked-by: Grant Likely <[email protected]>
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
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
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