Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 | /* SPDX-License-Identifier: GPL-2.0 */ /* * relocate_kernel.S for kexec * * Copyright (C) 2022 Loongson Technology Corporation Limited */ #include <linux/kexec.h> #include <asm/asm.h> #include <asm/asmmacro.h> #include <asm/regdef.h> #include <asm/loongarch.h> #include <asm/stackframe.h> #include <asm/addrspace.h> SYM_CODE_START(relocate_new_kernel) /* * a0: EFI boot flag for the new kernel * a1: Command line pointer for the new kernel * a2: System table pointer for the new kernel * a3: Start address to jump to after relocation * a4: Pointer to the current indirection page entry */ move s0, a4 /* * In case of a kdump/crash kernel, the indirection page is not * populated as the kernel is directly copied to a reserved location */ beqz s0, done process_entry: PTR_L s1, s0, 0 PTR_ADDI s0, s0, SZREG /* destination page */ andi s2, s1, IND_DESTINATION beqz s2, 1f li.w t0, ~0x1 and s3, s1, t0 /* store destination addr in s3 */ b process_entry 1: /* indirection page, update s0 */ andi s2, s1, IND_INDIRECTION beqz s2, 1f li.w t0, ~0x2 and s0, s1, t0 b process_entry 1: /* done page */ andi s2, s1, IND_DONE beqz s2, 1f b done 1: /* source page */ andi s2, s1, IND_SOURCE beqz s2, process_entry li.w t0, ~0x8 and s1, s1, t0 li.w s5, (1 << _PAGE_SHIFT) / SZREG copy_word: /* copy page word by word */ REG_L s4, s1, 0 REG_S s4, s3, 0 PTR_ADDI s3, s3, SZREG PTR_ADDI s1, s1, SZREG LONG_ADDI s5, s5, -1 beqz s5, process_entry b copy_word b process_entry done: ibar 0 dbar 0 /* * Jump to the new kernel, * make sure the values of a0, a1, a2 and a3 are not changed. */ jr a3 SYM_CODE_END(relocate_new_kernel) #ifdef CONFIG_SMP /* * Other CPUs should wait until code is relocated and * then start at the entry point from LOONGARCH_IOCSR_MBUF0. */ SYM_CODE_START(kexec_smp_wait) 1: li.w t0, 0x100 /* wait for init loop */ 2: addi.w t0, t0, -1 /* limit mailbox access */ bnez t0, 2b li.w t1, LOONGARCH_IOCSR_MBUF0 iocsrrd.w s0, t1 /* check PC as an indicator */ beqz s0, 1b iocsrrd.d s0, t1 /* get PC via mailbox */ li.d t0, CACHE_BASE or s0, s0, t0 /* s0 = TO_CACHE(s0) */ jr s0 /* jump to initial PC */ SYM_CODE_END(kexec_smp_wait) #endif relocate_new_kernel_end: SYM_DATA_START(relocate_new_kernel_size) PTR relocate_new_kernel_end - relocate_new_kernel SYM_DATA_END(relocate_new_kernel_size) |