Patchwork Write to HVC terminal from purgatory cod

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Submitter Mohan Kumar M
Date Oct. 16, 2009, 6:26 a.m.
Message ID <20091016062602.GC4995@in.ibm.com>
Download mbox | patch
Permalink /patch/36173/
State Not Applicable
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Comments

Mohan Kumar M - Oct. 16, 2009, 6:26 a.m.
[PATCH] Write to HVC terminal from purgatory code

Current x86/x86-64 kexec-tools print the message "I'm in purgatory" to serial
console/VGA while executing the purgatory code.  Implement this feature for
POWERPC pseries platform by using the H_PUT_TERM_CHAR hypervisor call by
printng to hvc console.

Includes the changes suggested by Michael Ellerman

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
---
 kexec/arch/ppc64/fs2dt.c               |   62 +++++++++++++++++++++++++++++++-
 kexec/arch/ppc64/kexec-elf-ppc64.c     |    7 ++++
 purgatory/arch/ppc64/Makefile          |    1 +
 purgatory/arch/ppc64/console-ppc64.c   |   14 +++++++
 purgatory/arch/ppc64/hvCall.S          |   26 +++++++++++++
 purgatory/arch/ppc64/hvCall.h          |    8 ++++
 purgatory/arch/ppc64/purgatory-ppc64.c |    1 +
 7 files changed, 118 insertions(+), 1 deletions(-)
 create mode 100644 purgatory/arch/ppc64/hvCall.S
 create mode 100644 purgatory/arch/ppc64/hvCall.h
Simon Horman - Nov. 25, 2009, 10:33 p.m.
On Fri, Oct 16, 2009 at 11:56:02AM +0530, M. Mohan Kumar wrote:
> [PATCH] Write to HVC terminal from purgatory code
> 
> Current x86/x86-64 kexec-tools print the message "I'm in purgatory" to serial
> console/VGA while executing the purgatory code.  Implement this feature for
> POWERPC pseries platform by using the H_PUT_TERM_CHAR hypervisor call by
> printng to hvc console.
> 
> Includes the changes suggested by Michael Ellerman

Sorry for the long delay, applied.

Patch

diff --git a/kexec/arch/ppc64/fs2dt.c b/kexec/arch/ppc64/fs2dt.c
index b01ff86..68a90e0 100644
--- a/kexec/arch/ppc64/fs2dt.c
+++ b/kexec/arch/ppc64/fs2dt.c
@@ -48,6 +48,7 @@  static int crash_param = 0;
 static char local_cmdline[COMMAND_LINE_SIZE] = { "" };
 extern mem_rgns_t usablemem_rgns;
 static struct bootblock bb[1];
+extern int my_debug;
 
 void reserve(unsigned long long where, unsigned long long length)
 {
@@ -434,6 +435,9 @@  static void putnode(void)
 	if (!strcmp(basename,"/chosen/")) {
 		size_t cmd_len = 0;
 		char *param = NULL;
+		char filename[MAXPATH];
+		char *buff;
+		int fd;
 
 		cmd_len = strlen(local_cmdline);
 		if (cmd_len != 0) {
@@ -446,7 +450,6 @@  static void putnode(void)
 
 		/* ... if not, grab root= from the old command line */
 		if (!param) {
-			char filename[MAXPATH];
 			FILE *fp;
 			char *last_cmdline = NULL;
 			char *old_param;
@@ -483,8 +486,65 @@  static void putnode(void)
 		dt += (cmd_len + 3)/4;
 
 		fprintf(stderr, "Modified cmdline:%s\n", local_cmdline);
+
+		/*
+		 * Determine the platform type/stdout type, so that purgatory
+		 * code can print 'I'm in purgatory' message. Currently only
+		 * pseries/hvcterminal is supported.
+		 */
+		strcpy(filename, pathname);
+		strncat(filename, "linux,stdout-path", MAXPATH);
+		fd = open(filename, O_RDONLY);
+		if (fd == -1) {
+			printf("Unable to find %s, printing from purgatory is diabled\n",
+														filename);
+			goto no_debug;
+		}
+		if (fstat(fd, &statbuf)) {
+			printf("Unable to stat %s, printing from purgatory is diabled\n",
+														filename);
+			close(fd);
+			goto no_debug;
+			
+		}
+
+		buff = malloc(statbuf.st_size);
+		if (!buff) {
+			printf("Can not allocate memory for buff\n");
+			close(fd);
+			goto no_debug;
+		}
+		read(fd, buff, statbuf.st_size);
+		close(fd);
+		strncpy(filename, "/proc/device-tree/", MAXPATH);
+		strncat(filename, buff, MAXPATH);
+		strncat(filename, "/compatible", MAXPATH);
+		fd = open(filename, O_RDONLY);
+		if (fd == -1) {
+			printf("Unable to find %s printing from purgatory is diabled\n",
+														filename);
+			goto no_debug;
+		}
+		if (fstat(fd, &statbuf)) {
+			printf("Unable to stat %s printing from purgatory is diabled\n",
+														filename);
+			close(fd);
+			goto no_debug;
+		}
+		buff = realloc(buff, statbuf.st_size);
+		if (!buff) {
+			printf("Can not allocate memory for buff\n");
+			close(fd);
+			goto no_debug;
+		}
+		read(fd, buff, statbuf.st_size);
+		if (!strcmp(buff, "hvterm1") || !strcmp(buff, "hvterm-protocol"))
+			my_debug = 1;
+		close(fd);
+		free(buff);
 	}
 
+no_debug:
 	for (i=0; i < numlist; i++) {
 		dp = namelist[i];
 		strcpy(dn, dp->d_name);
diff --git a/kexec/arch/ppc64/kexec-elf-ppc64.c b/kexec/arch/ppc64/kexec-elf-ppc64.c
index 21533cb..65fc42f 100644
--- a/kexec/arch/ppc64/kexec-elf-ppc64.c
+++ b/kexec/arch/ppc64/kexec-elf-ppc64.c
@@ -41,6 +41,8 @@ 
 uint64_t initrd_base, initrd_size;
 unsigned char reuse_initrd = 0;
 const char *ramdisk;
+/* Used for enabling printing message from purgatory code */
+int my_debug = 0;
 
 int elf_ppc64_probe(const char *buf, off_t len)
 {
@@ -296,6 +298,8 @@  int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 	toc_addr = my_r2(&info->rhdr);
 	elf_rel_set_symbol(&info->rhdr, "my_toc", &toc_addr, sizeof(toc_addr));
 
+	/* Set debug */
+	elf_rel_set_symbol(&info->rhdr, "debug", &my_debug, sizeof(my_debug));
 #ifdef DEBUG
 	my_kernel = 0;
 	my_dt_offset = 0;
@@ -304,6 +308,7 @@  int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 	my_stack = 0;
 	toc_addr = 0;
 	my_run_at_load = 0;
+	my_debug = 0;
 
 	elf_rel_get_symbol(&info->rhdr, "kernel", &my_kernel, sizeof(my_kernel));
 	elf_rel_get_symbol(&info->rhdr, "dt_offset", &my_dt_offset,
@@ -317,6 +322,7 @@  int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 	elf_rel_get_symbol(&info->rhdr, "stack", &my_stack, sizeof(my_stack));
 	elf_rel_get_symbol(&info->rhdr, "my_toc", &toc_addr,
 				sizeof(toc_addr));
+	elf_rel_get_symbol(&info->rhdr, "debug", &my_debug, sizeof(my_debug));
 
 	fprintf(stderr, "info->entry is %p\n", info->entry);
 	fprintf(stderr, "kernel is %llx\n", (unsigned long long)my_kernel);
@@ -329,6 +335,7 @@  int elf_ppc64_load(int argc, char **argv, const char *buf, off_t len,
 	fprintf(stderr, "stack is %llx\n", (unsigned long long)my_stack);
 	fprintf(stderr, "toc_addr is %llx\n", (unsigned long long)toc_addr);
 	fprintf(stderr, "purgatory size is %zu\n", purgatory_size);
+	fprintf(stderr, "debug is %d\n", my_debug);
 #endif
 
 	for (i = 0; i < info->nr_segments; i++)
diff --git a/purgatory/arch/ppc64/Makefile b/purgatory/arch/ppc64/Makefile
index aaa4046..40a9e99 100644
--- a/purgatory/arch/ppc64/Makefile
+++ b/purgatory/arch/ppc64/Makefile
@@ -3,6 +3,7 @@ 
 #
 
 ppc64_PURGATORY_SRCS += purgatory/arch/ppc64/v2wrap.S
+ppc64_PURGATORY_SRCS += purgatory/arch/ppc64/hvCall.S
 ppc64_PURGATORY_SRCS += purgatory/arch/ppc64/purgatory-ppc64.c
 ppc64_PURGATORY_SRCS += purgatory/arch/ppc64/console-ppc64.c
 ppc64_PURGATORY_SRCS += purgatory/arch/ppc64/crashdump_backup.c
diff --git a/purgatory/arch/ppc64/console-ppc64.c b/purgatory/arch/ppc64/console-ppc64.c
index d6da7b3..f766703 100644
--- a/purgatory/arch/ppc64/console-ppc64.c
+++ b/purgatory/arch/ppc64/console-ppc64.c
@@ -20,8 +20,22 @@ 
  */
 
 #include <purgatory.h>
+#include "hvCall.h"
 
+extern int debug;
+ 
 void putchar(int c)
 {
+	char buff[16];
+	unsigned long *lbuf = (unsigned long *)buff; 
+
+	if (!debug) /* running on non pseries */
+		return;
+
+	if (c == '\n')
+		putchar('\r');
+
+	buff[0] = c;
+	plpar_hcall_norets(H_PUT_TERM_CHAR, 0, 1, lbuf[0], lbuf[1]);
 	return;
 }
diff --git a/purgatory/arch/ppc64/hvCall.S b/purgatory/arch/ppc64/hvCall.S
new file mode 100644
index 0000000..bdc4cb0
--- /dev/null
+++ b/purgatory/arch/ppc64/hvCall.S
@@ -0,0 +1,26 @@ 
+/*
+ * This file contains the generic function to perform a call to the
+ * pSeries LPAR hypervisor.
+ *
+ * Taken from linux/arch/powerpc/platforms/pseries/hvCall.S
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define HVSC	.long 0x44000022
+.text
+	.machine ppc64
+.globl .plpar_hcall_norets
+.plpar_hcall_norets:
+	or	6,6,6			# medium low priority
+        mfcr	0
+        stw	0,8(1)
+
+        HVSC 				/* invoke the hypervisor */
+
+        lwz	0,8(1)
+        mtcrf	0xff,0
+        blr                             /* return r3 = status */
diff --git a/purgatory/arch/ppc64/hvCall.h b/purgatory/arch/ppc64/hvCall.h
new file mode 100644
index 0000000..187e24d
--- /dev/null
+++ b/purgatory/arch/ppc64/hvCall.h
@@ -0,0 +1,8 @@ 
+#ifndef HVCALL_H
+#define HVCALL_H
+
+#define H_PUT_TERM_CHAR	0x58
+
+long plpar_hcall_norets(unsigned long opcode, ...);
+
+#endif
diff --git a/purgatory/arch/ppc64/purgatory-ppc64.c b/purgatory/arch/ppc64/purgatory-ppc64.c
index 93f28d2..0b6d326 100644
--- a/purgatory/arch/ppc64/purgatory-ppc64.c
+++ b/purgatory/arch/ppc64/purgatory-ppc64.c
@@ -28,6 +28,7 @@  unsigned long stack = 0;
 unsigned long dt_offset = 0;
 unsigned long my_toc = 0;
 unsigned long kernel = 0;
+unsigned int debug = 0;
 
 void setup_arch(void)
 {