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Diffstat (limited to 'arch/mips/kernel/relocate_kernel.S')
| -rw-r--r-- | arch/mips/kernel/relocate_kernel.S | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S new file mode 100644 index 000000000..ac870893b --- /dev/null +++ b/arch/mips/kernel/relocate_kernel.S @@ -0,0 +1,190 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * relocate_kernel.S for kexec + * Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006 + */ + +#include <asm/asm.h> +#include <asm/asmmacro.h> +#include <asm/regdef.h> +#include <asm/mipsregs.h> +#include <asm/stackframe.h> +#include <asm/addrspace.h> + +LEAF(relocate_new_kernel) + PTR_L a0, arg0 + PTR_L a1, arg1 + PTR_L a2, arg2 + PTR_L a3, arg3 + + PTR_L s0, kexec_indirection_page + PTR_L s1, kexec_start_address + +process_entry: + PTR_L s2, (s0) + PTR_ADDIU s0, s0, SZREG + + /* + * In case of a kdump/crash kernel, the indirection page is not + * populated as the kernel is directly copied to a reserved location + */ + beqz s2, done + + /* destination page */ + and s3, s2, 0x1 + beq s3, zero, 1f + and s4, s2, ~0x1 /* store destination addr in s4 */ + b process_entry + +1: + /* indirection page, update s0 */ + and s3, s2, 0x2 + beq s3, zero, 1f + and s0, s2, ~0x2 + b process_entry + +1: + /* done page */ + and s3, s2, 0x4 + beq s3, zero, 1f + b done +1: + /* source page */ + and s3, s2, 0x8 + beq s3, zero, process_entry + and s2, s2, ~0x8 + li s6, (1 << _PAGE_SHIFT) / SZREG + +copy_word: + /* copy page word by word */ + REG_L s5, (s2) + REG_S s5, (s4) + PTR_ADDIU s4, s4, SZREG + PTR_ADDIU s2, s2, SZREG + LONG_ADDIU s6, s6, -1 + beq s6, zero, process_entry + b copy_word + b process_entry + +done: +#ifdef CONFIG_SMP + /* kexec_flag reset is signal to other CPUs what kernel + was moved to it's location. Note - we need relocated address + of kexec_flag. */ + + bal 1f + 1: move t1,ra; + PTR_LA t2,1b + PTR_LA t0,kexec_flag + PTR_SUB t0,t0,t2; + PTR_ADD t0,t1,t0; + LONG_S zero,(t0) +#endif + +#ifdef CONFIG_CPU_CAVIUM_OCTEON + /* We need to flush I-cache before jumping to new kernel. + * Unfortunately, this code is cpu-specific. + */ + .set push + .set noreorder + syncw + syncw + synci 0($0) + .set pop +#else + sync +#endif + /* jump to kexec_start_address */ + j s1 + END(relocate_new_kernel) + +#ifdef CONFIG_SMP +/* + * Other CPUs should wait until code is relocated and + * then start at entry (?) point. + */ +LEAF(kexec_smp_wait) + PTR_L a0, s_arg0 + PTR_L a1, s_arg1 + PTR_L a2, s_arg2 + PTR_L a3, s_arg3 + PTR_L s1, kexec_start_address + + /* Non-relocated address works for args and kexec_start_address ( old + * kernel is not overwritten). But we need relocated address of + * kexec_flag. + */ + + bal 1f +1: move t1,ra; + PTR_LA t2,1b + PTR_LA t0,kexec_flag + PTR_SUB t0,t0,t2; + PTR_ADD t0,t1,t0; + +1: LONG_L s0, (t0) + bne s0, zero,1b + +#ifdef CONFIG_CPU_CAVIUM_OCTEON + .set push + .set noreorder + synci 0($0) + .set pop +#else + sync +#endif + j s1 + END(kexec_smp_wait) +#endif + +#ifdef __mips64 + /* all PTR's must be aligned to 8 byte in 64-bit mode */ + .align 3 +#endif + +/* All parameters to new kernel are passed in registers a0-a3. + * kexec_args[0..3] are used to prepare register values. + */ + +kexec_args: + EXPORT(kexec_args) +arg0: PTR 0x0 +arg1: PTR 0x0 +arg2: PTR 0x0 +arg3: PTR 0x0 + .size kexec_args,PTRSIZE*4 + +#ifdef CONFIG_SMP +/* + * Secondary CPUs may have different kernel parameters in + * their registers a0-a3. secondary_kexec_args[0..3] are used + * to prepare register values. + */ +secondary_kexec_args: + EXPORT(secondary_kexec_args) +s_arg0: PTR 0x0 +s_arg1: PTR 0x0 +s_arg2: PTR 0x0 +s_arg3: PTR 0x0 + .size secondary_kexec_args,PTRSIZE*4 +kexec_flag: + LONG 0x1 + +#endif + +kexec_start_address: + EXPORT(kexec_start_address) + PTR 0x0 + .size kexec_start_address, PTRSIZE + +kexec_indirection_page: + EXPORT(kexec_indirection_page) + PTR 0 + .size kexec_indirection_page, PTRSIZE + +relocate_new_kernel_end: + +relocate_new_kernel_size: + EXPORT(relocate_new_kernel_size) + PTR relocate_new_kernel_end - relocate_new_kernel + .size relocate_new_kernel_size, PTRSIZE |