From: Stanislav Kinsburskii <[email protected]> This option allows kernel subsystems to modify (or create, if necessary) the Flattened Device Tree (fdt) using registered callbacks and then pass the modified version to the new kernel.
Signed-off-by: Stanislav Kinsburskii <[email protected]> --- arch/x86/Kconfig | 8 +++++++ arch/x86/kernel/kexec-bzimage64.c | 41 ++++++++++++++++++++++++++++++++++++- 2 files changed, 48 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index efb472e267ec..90da51fbb8f8 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2078,6 +2078,14 @@ config KEXEC_FILE_FDT This option enables passing existent Flattened Device Tree to the new kernel when kexec is invoked by the file based system call. +config KEXEC_FILE_FDT_CALLBACK + bool "Enable kexec fdt modification support" + depends on KEXEC_FILE_FDT + select LIBFDT + help + This option enables Flattened Device Tree modification (and creation + if needed) by kernel subsystems, registered corresponding callback. + config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index ab9ae02c9a5f..3c6df28d3637 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -384,11 +384,50 @@ static int bzImage64_probe(const char *buf, unsigned long len) return ret; } #ifdef CONFIG_KEXEC_FILE_FDT +#ifdef CONFIG_KEXEC_FILE_FDT_CALLBACK +static void *fdt_get_runtime(void) +{ + void *fdt; + size_t fdt_size = SZ_2M; + int status; + + /* It's nothing to do without existent fdt and any callbacks */ + if (!initial_boot_params && kexec_fdt_notify_list_empty()) + return NULL; + + fdt = kzalloc(fdt_size, GFP_KERNEL); + if (!fdt) + return NULL; + + if (initial_boot_params) + status = fdt_open_into(initial_boot_params, fdt, fdt_size); + else + status = fdt_create_empty_tree(fdt, fdt_size); + if (status != 0) { + pr_err("failed to get fdt\n"); + goto free_fdt; + } + + status = kexec_fdt_notify(fdt); + if (status) { + pr_err("fdt notification failed\n"); + goto free_fdt; + } + + fdt_pack(fdt); + + return fdt; + +free_fdt: + kfree(fdt); + return NULL; +} +#else static void *fdt_get_runtime(void) { return initial_boot_params; } - +#endif static int kexec_setup_fdt(struct kexec_buf *kbuf, struct boot_params *params) { void *fdt; _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
