To allow newer ARM platforms to use kexec, pass device tree information to the kernel during boot.
By default the dtb is found from /proc/device-tree. A user can specify a dtb file or use legacy ATAGs Signed-off-by: Matthew Leach <[email protected]> --- kexec/arch/arm/Makefile | 10 +++ kexec/arch/arm/include/arch/options.h | 6 +- kexec/arch/arm/kexec-zImage-arm.c | 140 ++++++++++++++++++++++++++++++++-- 3 files changed, 150 insertions(+), 6 deletions(-) diff --git a/kexec/arch/arm/Makefile b/kexec/arch/arm/Makefile index 288ec33..f25ce15 100644 --- a/kexec/arch/arm/Makefile +++ b/kexec/arch/arm/Makefile @@ -1,12 +1,22 @@ # # kexec arm (linux booting linux) # +include $(srcdir)/util_lib/dtc/Makefile.dtc + arm_KEXEC_SRCS= kexec/arch/arm/kexec-elf-rel-arm.c arm_KEXEC_SRCS+= kexec/arch/arm/kexec-zImage-arm.c arm_KEXEC_SRCS+= kexec/arch/arm/kexec-uImage-arm.c arm_KEXEC_SRCS+= kexec/arch/arm/kexec-arm.c arm_KEXEC_SRCS+= kexec/arch/arm/crashdump-arm.c +libfdt_SRCS += $(LIBFDT_SRCS:%=util_lib/libfdt/%) +dtc_SRCS += $(DTC_SRCS:%=util_lib/dtc/%) + +arm_KEXEC_SRCS+= $(libfdt_SRCS) +arm_KEXEC_SRCS+= $(dtc_SRCS) + +CPPFLAGS+=-I$(srcdir)/util_lib/libfdt + arm_UIMAGE = kexec/kexec-uImage.c arm_PHYS_TO_VIRT = kexec/arch/arm/phys_to_virt.c diff --git a/kexec/arch/arm/include/arch/options.h b/kexec/arch/arm/include/arch/options.h index d89c91f..b355c26 100644 --- a/kexec/arch/arm/include/arch/options.h +++ b/kexec/arch/arm/include/arch/options.h @@ -5,6 +5,8 @@ #define OPT_APPEND 'a' #define OPT_RAMDISK 'r' +#define OPT_DTB (OPT_ARCH_MAX+0) +#define OPT_ATAGS (OPT_ARCH_MAX+1) /* Options relevant to the architecture (excluding loader-specific ones), * in this case none: @@ -33,7 +35,9 @@ { "command-line", 1, 0, OPT_APPEND }, \ { "append", 1, 0, OPT_APPEND }, \ { "initrd", 1, 0, OPT_RAMDISK }, \ - { "ramdisk", 1, 0, OPT_RAMDISK }, + { "ramdisk", 1, 0, OPT_RAMDISK }, \ + { "dtb", 1, 0, OPT_DTB }, \ + { "atags", 0, 0, OPT_ATAGS }, #define KEXEC_ALL_OPT_STR KEXEC_ARCH_OPT_STR "a:r:" diff --git a/kexec/arch/arm/kexec-zImage-arm.c b/kexec/arch/arm/kexec-zImage-arm.c index 88a6c29..74028b8 100644 --- a/kexec/arch/arm/kexec-zImage-arm.c +++ b/kexec/arch/arm/kexec-zImage-arm.c @@ -13,6 +13,8 @@ #include <unistd.h> #include <getopt.h> #include <unistd.h> +#include <dtc.h> +#include <libfdt.h> #include <arch/options.h> #include "../../kexec.h" #include "../../kexec-syscall.h" @@ -96,6 +98,8 @@ void zImage_arm_usage(void) " --append=STRING Set the kernel command line to STRING.\n" " --initrd=FILE Use FILE as the kernel's initial ramdisk.\n" " --ramdisk=FILE Use FILE as the kernel's initial ramdisk.\n" + " --dtb=FILE Use FILE as the fdt blob.\n" + " --atags Use ATAGs instead of device-tree.\n" ); } @@ -208,6 +212,63 @@ int atag_arm_load(struct kexec_info *info, unsigned long base, return 0; } +void dtb_fixup_chosen_node(char **dtb_buf, off_t *buf_sz, const char *command_line, + unsigned long initrd_start, unsigned long initrd_end) +{ + if (command_line || initrd_start != initrd_end) { + int chosen_offset; + int root_offset; + int command_line_len = strlen(command_line); + off_t new_buf_sz = *buf_sz + command_line_len + 0x50; /* extra space for new node */ + void *new_buf = malloc(new_buf_sz); + + fdt_open_into(*dtb_buf, new_buf, new_buf_sz); + + root_offset = fdt_path_offset(new_buf, "/"); + chosen_offset = fdt_path_offset(new_buf, "/chosen"); + if (chosen_offset == -FDT_ERR_NOTFOUND) { + chosen_offset = fdt_add_subnode(new_buf, root_offset, "chosen"); + } + if (chosen_offset < 0) { + fprintf(stderr, "Warning: failed to find the chosen node, a specified command line and" + " initrd will not be set.\n"); + free(new_buf); + return; + } + + /* + * Add the 'bootargs' proerpty to the chosen node if the command + * line is specified. + */ + if (command_line) { + if (fdt_setprop_string(new_buf, chosen_offset, + "bootargs", command_line) < 0) { + fprintf(stderr, "Warning: failed to set the command line.\n"); + free(new_buf); + return; + } + } + + /* + * Add the 'initrd-start' and 'initrd-end' properties to the + * chosen node if an initrd is specified. + */ + if (initrd_start != initrd_end) { + if ((fdt_setprop_cell(new_buf, chosen_offset, + "initrd-start", initrd_start) < 0) || + (fdt_setprop_cell(new_buf, chosen_offset, + "initrd-end", initrd_end) < 0)) { + fprintf(stderr, "Warning: failed to set the initrd addresses.\n"); + return; + } + } + + free(*dtb_buf); + *dtb_buf = new_buf; + *buf_sz = new_buf_sz; + } +} + int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, struct kexec_info *info) { @@ -222,6 +283,12 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, off_t ramdisk_length; off_t ramdisk_offset; int opt; + int use_atags; + char *dtb_buf; + off_t dtb_length; + char *dtb_file; + off_t dtb_offset; + /* See options.h -- add any more there, too. */ static const struct option options[] = { KEXEC_ARCH_OPTIONS @@ -229,6 +296,8 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, { "append", 1, 0, OPT_APPEND }, { "initrd", 1, 0, OPT_RAMDISK }, { "ramdisk", 1, 0, OPT_RAMDISK }, + { "dtb", 1, 0, OPT_DTB }, + { "atags", 0, 0, OPT_ATAGS }, { 0, 0, 0, 0 }, }; static const char short_options[] = KEXEC_ARCH_OPT_STR "a:r:"; @@ -241,6 +310,8 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, ramdisk = 0; ramdisk_buf = 0; ramdisk_length = 0; + use_atags = 0; + dtb_file = NULL; while((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) { switch(opt) { default: @@ -257,8 +328,21 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, case OPT_RAMDISK: ramdisk = optarg; break; + case OPT_DTB: + dtb_file = optarg; + break; + case OPT_ATAGS: + use_atags = 1; + break; } } + + if (use_atags && dtb_file) { + fprintf(stderr, "You can only use ATAGs if you don't specify a " + "dtb file.\n"); + return -1; + } + if (command_line) { command_line_len = strlen(command_line) + 1; if (command_line_len > COMMAND_LINE_SIZE) @@ -315,12 +399,58 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len, /* assume the maximum kernel compression ratio is 4, * and just to be safe, place ramdisk after that */ - ramdisk_offset = base + len * 4; + ramdisk_offset = base + len * 4; - if (atag_arm_load(info, base + atag_offset, - command_line, command_line_len, - ramdisk_buf, ramdisk_length, ramdisk_offset) == -1) - return -1; + if (use_atags) { + /* + * use ATAGs from /proc/atags + */ + if (atag_arm_load(info, base + atag_offset, + command_line, command_line_len, + ramdisk_buf, ramdisk_length, ramdisk_offset) == -1) + return -1; + } else { + /* + * Read a user-specified DTB file. + */ + if (dtb_file) { + dtb_buf = slurp_file(dtb_file, &dtb_length); + } else { + /* + * Extract the DTB from /proc/device-tree. + */ + struct boot_info *bi; + bi = dt_from_fs("/proc/device-tree"); + dtb_buf = dt_to_blob_buf(&dtb_length, bi, DEFAULT_FDT_VERSION); + } + + dtb_fixup_chosen_node(&dtb_buf, &dtb_length, command_line, + ramdisk_offset, ramdisk_offset + ramdisk_length); + + if (fdt_check_header(dtb_buf) != 0) { + fprintf(stderr, "Invalid FDT buffer.\n"); + return -1; + } + + if (base + atag_offset + dtb_length > base + offset) { + fprintf(stderr, "DTB too large!\n"); + return -1; + } + + if (ramdisk) { + add_segment(info, ramdisk_buf, ramdisk_length, + ramdisk_offset, ramdisk_length); + } + + /* Stick the dtb at the end of the initrd and page + * align it. + */ + dtb_offset = ramdisk_offset + ramdisk_length + getpagesize(); + dtb_offset &= ~(getpagesize() - 1); + + add_segment(info, dtb_buf, dtb_length, + dtb_offset, dtb_length); + } add_segment(info, buf, len, base + offset, len); -- 1.7.12 _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
