xref: /openbmc/linux/arch/s390/boot/ipl_parm.c (revision 6d99a79c)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/ctype.h>
4 #include <asm/ebcdic.h>
5 #include <asm/sclp.h>
6 #include <asm/sections.h>
7 #include <asm/boot_data.h>
8 #include "boot.h"
9 
10 char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
11 struct ipl_parameter_block __bootdata(early_ipl_block);
12 int __bootdata(early_ipl_block_valid);
13 
14 unsigned long __bootdata(memory_end);
15 int __bootdata(memory_end_set);
16 int __bootdata(noexec_disabled);
17 
18 static inline int __diag308(unsigned long subcode, void *addr)
19 {
20 	register unsigned long _addr asm("0") = (unsigned long)addr;
21 	register unsigned long _rc asm("1") = 0;
22 	unsigned long reg1, reg2;
23 	psw_t old = S390_lowcore.program_new_psw;
24 
25 	asm volatile(
26 		"	epsw	%0,%1\n"
27 		"	st	%0,%[psw_pgm]\n"
28 		"	st	%1,%[psw_pgm]+4\n"
29 		"	larl	%0,1f\n"
30 		"	stg	%0,%[psw_pgm]+8\n"
31 		"	diag	%[addr],%[subcode],0x308\n"
32 		"1:	nopr	%%r7\n"
33 		: "=&d" (reg1), "=&a" (reg2),
34 		  [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
35 		  [addr] "+d" (_addr), "+d" (_rc)
36 		: [subcode] "d" (subcode)
37 		: "cc", "memory");
38 	S390_lowcore.program_new_psw = old;
39 	return _rc;
40 }
41 
42 void store_ipl_parmblock(void)
43 {
44 	int rc;
45 
46 	rc = __diag308(DIAG308_STORE, &early_ipl_block);
47 	if (rc == DIAG308_RC_OK &&
48 	    early_ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION)
49 		early_ipl_block_valid = 1;
50 }
51 
52 static size_t scpdata_length(const char *buf, size_t count)
53 {
54 	while (count) {
55 		if (buf[count - 1] != '\0' && buf[count - 1] != ' ')
56 			break;
57 		count--;
58 	}
59 	return count;
60 }
61 
62 static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size,
63 					  const struct ipl_parameter_block *ipb)
64 {
65 	size_t count;
66 	size_t i;
67 	int has_lowercase;
68 
69 	count = min(size - 1, scpdata_length(ipb->ipl_info.fcp.scp_data,
70 					     ipb->ipl_info.fcp.scp_data_len));
71 	if (!count)
72 		goto out;
73 
74 	has_lowercase = 0;
75 	for (i = 0; i < count; i++) {
76 		if (!isascii(ipb->ipl_info.fcp.scp_data[i])) {
77 			count = 0;
78 			goto out;
79 		}
80 		if (!has_lowercase && islower(ipb->ipl_info.fcp.scp_data[i]))
81 			has_lowercase = 1;
82 	}
83 
84 	if (has_lowercase)
85 		memcpy(dest, ipb->ipl_info.fcp.scp_data, count);
86 	else
87 		for (i = 0; i < count; i++)
88 			dest[i] = tolower(ipb->ipl_info.fcp.scp_data[i]);
89 out:
90 	dest[count] = '\0';
91 	return count;
92 }
93 
94 static void append_ipl_block_parm(void)
95 {
96 	char *parm, *delim;
97 	size_t len, rc = 0;
98 
99 	len = strlen(early_command_line);
100 
101 	delim = early_command_line + len;    /* '\0' character position */
102 	parm = early_command_line + len + 1; /* append right after '\0' */
103 
104 	switch (early_ipl_block.hdr.pbt) {
105 	case DIAG308_IPL_TYPE_CCW:
106 		rc = ipl_block_get_ascii_vmparm(
107 			parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
108 		break;
109 	case DIAG308_IPL_TYPE_FCP:
110 		rc = ipl_block_get_ascii_scpdata(
111 			parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
112 		break;
113 	}
114 	if (rc) {
115 		if (*parm == '=')
116 			memmove(early_command_line, parm + 1, rc);
117 		else
118 			*delim = ' '; /* replace '\0' with space */
119 	}
120 }
121 
122 static inline int has_ebcdic_char(const char *str)
123 {
124 	int i;
125 
126 	for (i = 0; str[i]; i++)
127 		if (str[i] & 0x80)
128 			return 1;
129 	return 0;
130 }
131 
132 void setup_boot_command_line(void)
133 {
134 	COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
135 	/* convert arch command line to ascii if necessary */
136 	if (has_ebcdic_char(COMMAND_LINE))
137 		EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
138 	/* copy arch command line */
139 	strcpy(early_command_line, strim(COMMAND_LINE));
140 
141 	/* append IPL PARM data to the boot command line */
142 	if (early_ipl_block_valid)
143 		append_ipl_block_parm();
144 }
145 
146 static char command_line_buf[COMMAND_LINE_SIZE] __section(.data);
147 static void parse_mem_opt(void)
148 {
149 	char *param, *val;
150 	bool enabled;
151 	char *args;
152 	int rc;
153 
154 	args = strcpy(command_line_buf, early_command_line);
155 	while (*args) {
156 		args = next_arg(args, &param, &val);
157 
158 		if (!strcmp(param, "mem")) {
159 			memory_end = memparse(val, NULL);
160 			memory_end_set = 1;
161 		}
162 
163 		if (!strcmp(param, "noexec")) {
164 			rc = kstrtobool(val, &enabled);
165 			if (!rc && !enabled)
166 				noexec_disabled = 1;
167 		}
168 	}
169 }
170 
171 void setup_memory_end(void)
172 {
173 	parse_mem_opt();
174 #ifdef CONFIG_CRASH_DUMP
175 	if (!OLDMEM_BASE && early_ipl_block_valid &&
176 	    early_ipl_block.hdr.pbt == DIAG308_IPL_TYPE_FCP &&
177 	    early_ipl_block.ipl_info.fcp.opt == DIAG308_IPL_OPT_DUMP) {
178 		if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
179 			memory_end_set = 1;
180 	}
181 #endif
182 }
183