1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/string.h>
4 #include <asm/sections.h>
10 #include "compressed/decompressor.h"
13 extern char __boot_data_start[], __boot_data_end[];
14 extern char __boot_data_preserved_start[], __boot_data_preserved_end[];
15 unsigned long __bootdata_preserved(__kaslr_offset);
18 * Some code and data needs to stay below 2 GB, even when the kernel would be
19 * relocated above 2 GB, because it has to use 31 bit addresses.
20 * Such code and data is part of the .dma section, and its location is passed
21 * over to the decompressed / relocated kernel via the .boot.preserved.data
24 extern char _sdma[], _edma[];
25 extern char _stext_dma[], _etext_dma[];
26 extern struct exception_table_entry _start_dma_ex_table[];
27 extern struct exception_table_entry _stop_dma_ex_table[];
28 unsigned long __bootdata_preserved(__sdma) = __pa(&_sdma);
29 unsigned long __bootdata_preserved(__edma) = __pa(&_edma);
30 unsigned long __bootdata_preserved(__stext_dma) = __pa(&_stext_dma);
31 unsigned long __bootdata_preserved(__etext_dma) = __pa(&_etext_dma);
32 struct exception_table_entry *
33 __bootdata_preserved(__start_dma_ex_table) = _start_dma_ex_table;
34 struct exception_table_entry *
35 __bootdata_preserved(__stop_dma_ex_table) = _stop_dma_ex_table;
37 int _diag210_dma(struct diag210 *addr);
38 int _diag26c_dma(void *req, void *resp, enum diag26c_sc subcode);
39 int _diag14_dma(unsigned long rx, unsigned long ry1, unsigned long subcode);
40 void _diag0c_dma(struct hypfs_diag0c_entry *entry);
41 void _diag308_reset_dma(void);
42 struct diag_ops __bootdata_preserved(diag_dma_ops) = {
43 .diag210 = _diag210_dma,
44 .diag26c = _diag26c_dma,
45 .diag14 = _diag14_dma,
46 .diag0c = _diag0c_dma,
47 .diag308_reset = _diag308_reset_dma
49 static struct diag210 _diag210_tmp_dma __section(".dma.data");
50 struct diag210 *__bootdata_preserved(__diag210_tmp_dma) = &_diag210_tmp_dma;
51 void _swsusp_reset_dma(void);
52 unsigned long __bootdata_preserved(__swsusp_reset_dma) = __pa(_swsusp_reset_dma);
56 sclp_early_printk("\n\n");
58 sclp_early_printk("\n\n -- System halted");
63 #ifdef CONFIG_KERNEL_UNCOMPRESSED
64 unsigned long mem_safe_offset(void)
66 return vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size;
70 static void rescue_initrd(unsigned long addr)
72 if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
74 if (!INITRD_START || !INITRD_SIZE)
76 if (addr <= INITRD_START)
78 memmove((void *)addr, (void *)INITRD_START, INITRD_SIZE);
82 static void copy_bootdata(void)
84 if (__boot_data_end - __boot_data_start != vmlinux.bootdata_size)
85 error(".boot.data section size mismatch");
86 memcpy((void *)vmlinux.bootdata_off, __boot_data_start, vmlinux.bootdata_size);
87 if (__boot_data_preserved_end - __boot_data_preserved_start != vmlinux.bootdata_preserved_size)
88 error(".boot.preserved.data section size mismatch");
89 memcpy((void *)vmlinux.bootdata_preserved_off, __boot_data_preserved_start, vmlinux.bootdata_preserved_size);
92 static void handle_relocs(unsigned long offset)
94 Elf64_Rela *rela_start, *rela_end, *rela;
95 int r_type, r_sym, rc;
99 rela_start = (Elf64_Rela *) vmlinux.rela_dyn_start;
100 rela_end = (Elf64_Rela *) vmlinux.rela_dyn_end;
101 dynsym = (Elf64_Sym *) vmlinux.dynsym_start;
102 for (rela = rela_start; rela < rela_end; rela++) {
103 loc = rela->r_offset + offset;
104 val = rela->r_addend + offset;
105 r_sym = ELF64_R_SYM(rela->r_info);
107 val += dynsym[r_sym].st_value;
108 r_type = ELF64_R_TYPE(rela->r_info);
109 rc = arch_kexec_do_relocs(r_type, (void *) loc, val, 0);
111 error("Unknown relocation type");
115 static void clear_bss_section(void)
117 memset((void *)vmlinux.default_lma + vmlinux.image_size, 0, vmlinux.bss_size);
120 void startup_kernel(void)
122 unsigned long random_lma;
123 unsigned long safe_addr;
126 store_ipl_parmblock();
127 safe_addr = mem_safe_offset();
128 safe_addr = read_ipl_report(safe_addr);
130 rescue_initrd(safe_addr);
131 sclp_early_read_info();
132 setup_boot_command_line();
133 parse_boot_command_line();
137 random_lma = __kaslr_offset = 0;
138 if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_enabled) {
139 random_lma = get_random_base(safe_addr);
141 __kaslr_offset = random_lma - vmlinux.default_lma;
142 img = (void *)vmlinux.default_lma;
143 vmlinux.default_lma += __kaslr_offset;
144 vmlinux.entry += __kaslr_offset;
145 vmlinux.bootdata_off += __kaslr_offset;
146 vmlinux.bootdata_preserved_off += __kaslr_offset;
147 vmlinux.rela_dyn_start += __kaslr_offset;
148 vmlinux.rela_dyn_end += __kaslr_offset;
149 vmlinux.dynsym_start += __kaslr_offset;
153 if (!IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED)) {
154 img = decompress_kernel();
155 memmove((void *)vmlinux.default_lma, img, vmlinux.image_size);
156 } else if (__kaslr_offset)
157 memcpy((void *)vmlinux.default_lma, img, vmlinux.image_size);
161 if (IS_ENABLED(CONFIG_RELOCATABLE))
162 handle_relocs(__kaslr_offset);
164 if (__kaslr_offset) {
165 /* Clear non-relocated kernel */
166 if (IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED))
167 memset(img, 0, vmlinux.image_size);