s390: move ipl block and cmd line handling to early boot phase

To distinguish zfcpdump case and to be able to parse some of the kernel
command line arguments early (e.g. mem=) ipl block retrieval and command
line construction code is moved to the early boot phase.

"memory_end" is set up correctly respecting "mem=" and hsa_size in case
of the zfcpdump.

arch/s390/boot/string.c is introduced to provide string handling and
command line parsing functions to early boot phase code for the compressed
kernel image case.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 173 insertions, 0 deletions

diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
new file mode 100644
index 000000000000..7f8e546400a1
--- /dev/null
+++ b/arch/s390/boot/ipl_parm.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/ctype.h>
+#include <asm/ebcdic.h>
+#include <asm/sclp.h>
+#include <asm/sections.h>
+#include <asm/boot_data.h>
+#include "boot.h"
+
+char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
+struct ipl_parameter_block __bootdata(early_ipl_block);
+int __bootdata(early_ipl_block_valid);
+
+unsigned long __bootdata(memory_end);
+int __bootdata(memory_end_set);
+
+static inline int __diag308(unsigned long subcode, void *addr)
+{
+	register unsigned long _addr asm("0") = (unsigned long)addr;
+	register unsigned long _rc asm("1") = 0;
+	unsigned long reg1, reg2;
+	psw_t old = S390_lowcore.program_new_psw;
+
+	asm volatile(
+		"	epsw	%0,%1\n"
+		"	st	%0,%[psw_pgm]\n"
+		"	st	%1,%[psw_pgm]+4\n"
+		"	larl	%0,1f\n"
+		"	stg	%0,%[psw_pgm]+8\n"
+		"	diag	%[addr],%[subcode],0x308\n"
+		"1:	nopr	%%r7\n"
+		: "=&d" (reg1), "=&a" (reg2),
+		  [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
+		  [addr] "+d" (_addr), "+d" (_rc)
+		: [subcode] "d" (subcode)
+		: "cc", "memory");
+	S390_lowcore.program_new_psw = old;
+	return _rc;
+}
+
+void store_ipl_parmblock(void)
+{
+	int rc;
+
+	rc = __diag308(DIAG308_STORE, &early_ipl_block);
+	if (rc == DIAG308_RC_OK &&
+	    early_ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION)
+		early_ipl_block_valid = 1;
+}
+
+static size_t scpdata_length(const char *buf, size_t count)
+{
+	while (count) {
+		if (buf[count - 1] != '\0' && buf[count - 1] != ' ')
+			break;
+		count--;
+	}
+	return count;
+}
+
+static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size,
+					  const struct ipl_parameter_block *ipb)
+{
+	size_t count;
+	size_t i;
+	int has_lowercase;
+
+	count = min(size - 1, scpdata_length(ipb->ipl_info.fcp.scp_data,
+					     ipb->ipl_info.fcp.scp_data_len));
+	if (!count)
+		goto out;
+
+	has_lowercase = 0;
+	for (i = 0; i < count; i++) {
+		if (!isascii(ipb->ipl_info.fcp.scp_data[i])) {
+			count = 0;
+			goto out;
+		}
+		if (!has_lowercase && islower(ipb->ipl_info.fcp.scp_data[i]))
+			has_lowercase = 1;
+	}
+
+	if (has_lowercase)
+		memcpy(dest, ipb->ipl_info.fcp.scp_data, count);
+	else
+		for (i = 0; i < count; i++)
+			dest[i] = tolower(ipb->ipl_info.fcp.scp_data[i]);
+out:
+	dest[count] = '\0';
+	return count;
+}
+
+static void append_ipl_block_parm(void)
+{
+	char *parm, *delim;
+	size_t len, rc = 0;
+
+	len = strlen(early_command_line);
+
+	delim = early_command_line + len;    /* '\0' character position */
+	parm = early_command_line + len + 1; /* append right after '\0' */
+
+	switch (early_ipl_block.hdr.pbt) {
+	case DIAG308_IPL_TYPE_CCW:
+		rc = ipl_block_get_ascii_vmparm(
+			parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
+		break;
+	case DIAG308_IPL_TYPE_FCP:
+		rc = ipl_block_get_ascii_scpdata(
+			parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
+		break;
+	}
+	if (rc) {
+		if (*parm == '=')
+			memmove(early_command_line, parm + 1, rc);
+		else
+			*delim = ' '; /* replace '\0' with space */
+	}
+}
+
+static inline int has_ebcdic_char(const char *str)
+{
+	int i;
+
+	for (i = 0; str[i]; i++)
+		if (str[i] & 0x80)
+			return 1;
+	return 0;
+}
+
+void setup_boot_command_line(void)
+{
+	COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
+	/* convert arch command line to ascii if necessary */
+	if (has_ebcdic_char(COMMAND_LINE))
+		EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
+	/* copy arch command line */
+	strcpy(early_command_line, strim(COMMAND_LINE));
+
+	/* append IPL PARM data to the boot command line */
+	if (early_ipl_block_valid)
+		append_ipl_block_parm();
+}
+
+static char command_line_buf[COMMAND_LINE_SIZE] __section(.data);
+static void parse_mem_opt(void)
+{
+	char *args;
+	char *param, *val;
+
+	args = strcpy(command_line_buf, early_command_line);
+	while (*args) {
+		args = next_arg(args, &param, &val);
+
+		if (!strcmp(param, "mem")) {
+			memory_end = memparse(val, NULL);
+			memory_end_set = 1;
+		}
+	}
+}
+
+void setup_memory_end(void)
+{
+	parse_mem_opt();
+#ifdef CONFIG_CRASH_DUMP
+	if (!OLDMEM_BASE && early_ipl_block_valid &&
+	    early_ipl_block.hdr.pbt == DIAG308_IPL_TYPE_FCP &&
+	    early_ipl_block.ipl_info.fcp.opt == DIAG308_IPL_OPT_DUMP) {
+		if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
+			memory_end_set = 1;
+	}
+#endif
+}