1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/init.h>
4 #include <linux/libfdt.h>
5 #include <linux/string.h>
6 #include <asm/pgtable.h>
7 #include <asm/setup.h>
8
9 #include "pi.h"
10
11 static char early_cmdline[COMMAND_LINE_SIZE];
12
get_early_cmdline(uintptr_t dtb_pa)13 static char *get_early_cmdline(uintptr_t dtb_pa)
14 {
15 const char *fdt_cmdline = NULL;
16 unsigned int fdt_cmdline_size = 0;
17 int chosen_node;
18
19 if (!IS_ENABLED(CONFIG_CMDLINE_FORCE)) {
20 chosen_node = fdt_path_offset((void *)dtb_pa, "/chosen");
21 if (chosen_node >= 0) {
22 fdt_cmdline = fdt_getprop((void *)dtb_pa, chosen_node,
23 "bootargs", NULL);
24 if (fdt_cmdline) {
25 fdt_cmdline_size = strlen(fdt_cmdline);
26 strscpy(early_cmdline, fdt_cmdline,
27 COMMAND_LINE_SIZE);
28 }
29 }
30 }
31
32 if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
33 IS_ENABLED(CONFIG_CMDLINE_FORCE) ||
34 fdt_cmdline_size == 0 /* CONFIG_CMDLINE_FALLBACK */) {
35 strlcat(early_cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
36 }
37
38 return early_cmdline;
39 }
40
match_noXlvl(char * cmdline)41 static u64 match_noXlvl(char *cmdline)
42 {
43 if (strstr(cmdline, "no4lvl"))
44 return SATP_MODE_48;
45 else if (strstr(cmdline, "no5lvl"))
46 return SATP_MODE_57;
47
48 return 0;
49 }
50
set_satp_mode_from_cmdline(uintptr_t dtb_pa)51 u64 set_satp_mode_from_cmdline(uintptr_t dtb_pa)
52 {
53 char *cmdline = get_early_cmdline(dtb_pa);
54
55 return match_noXlvl(cmdline);
56 }
57
match_nokaslr(char * cmdline)58 static bool match_nokaslr(char *cmdline)
59 {
60 return strstr(cmdline, "nokaslr");
61 }
62
set_nokaslr_from_cmdline(uintptr_t dtb_pa)63 bool set_nokaslr_from_cmdline(uintptr_t dtb_pa)
64 {
65 char *cmdline = get_early_cmdline(dtb_pa);
66
67 return match_nokaslr(cmdline);
68 }
69