IPMI: Introduce attention call

Presently abort() function is not working on BMC based machine. System
hangs after abort/assert call. We have to reboot machine from BMC (IPMI
command or BMC console).

This patch introduces attention functionality for BMC based machine.
It logs eSEL event that contains OPAL version, file info and backtrace.
And calls cec_reboot... which takes care of rebooting host.

Note:
  - This patch uses ipmi_queue_msg() instead of ipmi_queue_msg_sync() as
    we are having some issues with sync path. This will resolved once we
    sort out [1].
  - This patch calls cec_reboot to reboot machine after logging eSEL event.
    It queues IPMI message and bt_poll() should be working until we pass
    reboot IPMI message to BMC. Hence we have while loop with time_wait_ms().
    Alternatively we can use xscom_trigger_xstop().. but it will stop
    immediately and eSEL logging fails.

[1] https://lists.ozlabs.org/pipermail/skiboot/2015-August/001824.html

Sample eSEL output after assert call:
------------------------------------
[hegdevasant@hegdevasant bin]$ strings fir01bmc.150820.120511.eSel.binary
BB821410
AT8335-GTA000000000000
AT8335-GTA000000000000UD
ATDESC
OPAL version : skiboot-5.1.1-44-geae3999-hegdevasant-dirty-bb31bfd
File info : core/init.c:463:0
CPU 0060 Backtrace:
 S: 0000000031d83bc0 R: 000000003006086c   .ipmi_terminate+0x110
 S: 0000000031d83c60 R: 0000000030017f90   ._abort+0x80
 S: 0000000031d83ce0 R: 0000000030017fd8   .assert_fail+0x34
 S: 0000000031d83d60 R: 0000000030013dcc   .load_and_boot_kernel+0x784
 S: 0000000031d83e30 R: 000000003001437c   .main_cpu_entry+0x57c
 S: 0000000031d83f00 R: 0000000030002544   boot_entry+0x194

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

7 files changed, 93 insertions, 1 deletions

diff --git a/hw/ipmi/Makefile.inc b/hw/ipmi/Makefile.inc
index 06cdc96..6325369 100644
--- a/hw/ipmi/Makefile.inc
+++ b/hw/ipmi/Makefile.inc
@@ -1,7 +1,7 @@
 SUBDIRS += hw/ipmi
 
 IPMI_OBJS  = ipmi-rtc.o ipmi-power.o ipmi-opal.o ipmi-fru.o ipmi-sel.o
-IPMI_OBJS += ipmi-watchdog.o ipmi-sensor.o
+IPMI_OBJS += ipmi-watchdog.o ipmi-sensor.o ipmi-attn.o
 
 IPMI = hw/ipmi/built-in.o
 $(IPMI): $(IPMI_OBJS:%=hw/ipmi/%)
diff --git a/hw/ipmi/ipmi-attn.c b/hw/ipmi/ipmi-attn.c
new file mode 100644
index 0000000..a3e4878
--- /dev/null
+++ b/hw/ipmi/ipmi-attn.c
@@ -0,0 +1,85 @@
+/* Copyright 2015 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errorlog.h>
+#include <ipmi.h>
+#include <pel.h>
+#include <platform.h>
+#include <processor.h>
+#include <skiboot.h>
+#include <stack.h>
+#include <timebase.h>
+
+/* Use same attention SRC for BMC based machine */
+DEFINE_LOG_ENTRY(OPAL_RC_ATTN, OPAL_PLATFORM_ERR_EVT,
+		 OPAL_ATTN, OPAL_PLATFORM_FIRMWARE,
+		 OPAL_ERROR_PANIC, OPAL_ABNORMAL_POWER_OFF);
+
+/* Maximum buffer size to capture backtrace and other useful information */
+#define IPMI_TI_BUFFER_SIZE	(IPMI_MAX_PEL_SIZE - PEL_MIN_SIZE)
+static char ti_buffer[IPMI_TI_BUFFER_SIZE];
+
+#define STACK_BUF_ENTRIES       20
+struct bt_entry bt_buf[STACK_BUF_ENTRIES];
+
+/* Log eSEL event with OPAL backtrace */
+static void ipmi_log_terminate_event(const char *msg)
+{
+	unsigned int bt_entry_cnt = STACK_BUF_ENTRIES;
+	unsigned int ti_len;
+	unsigned int ti_size;
+	struct errorlog *elog_buf;
+
+	/* Fill OPAL version */
+	ti_len = snprintf(ti_buffer, IPMI_TI_BUFFER_SIZE,
+			  "OPAL version : %s\n", version);
+
+	/* File information */
+	ti_len += snprintf(ti_buffer + ti_len, IPMI_TI_BUFFER_SIZE - ti_len,
+			   "File info : %s\n", msg);
+	ti_size = IPMI_TI_BUFFER_SIZE - ti_len;
+
+	/* Backtrace */
+	__backtrace(bt_buf, &bt_entry_cnt);
+	__print_backtrace(mfspr(SPR_PIR), bt_buf, bt_entry_cnt,
+			  ti_buffer + ti_len, &ti_size, true);
+
+	/* Create eSEL event and commit */
+	elog_buf = opal_elog_create(&e_info(OPAL_RC_ATTN), 0);
+	log_append_data(elog_buf, (char *)&ti_buffer, ti_len + ti_size);
+	log_commit(elog_buf);
+}
+
+void __attribute__((noreturn)) ipmi_terminate(const char *msg)
+{
+	/* Terminate called before initializing IPMI (early abort) */
+	if (!ipmi_present()) {
+		if (platform.cec_reboot())
+			platform.cec_reboot();
+		goto out;
+	}
+
+	/* Log eSEL event */
+	ipmi_log_terminate_event(msg);
+
+	/* Reboot call */
+	if (platform.cec_reboot())
+		platform.cec_reboot();
+
+out:
+	while (1)
+		time_wait_ms(100);
+}
diff --git a/include/ipmi.h b/include/ipmi.h
index b33041b..99a9094 100644
--- a/include/ipmi.h
+++ b/include/ipmi.h
@@ -276,4 +276,7 @@ uint8_t ipmi_get_sensor_number(uint8_t sensor_type);
 /* Set the boot count once the OS is up and running */
 int ipmi_set_boot_count(void);
 
+/* Terminate immediate */
+void __attribute__((noreturn)) ipmi_terminate(const char *msg);
+
 #endif
diff --git a/platforms/astbmc/firestone.c b/platforms/astbmc/firestone.c
index cda9d06..445a28b 100644
--- a/platforms/astbmc/firestone.c
+++ b/platforms/astbmc/firestone.c
@@ -47,4 +47,5 @@ DECLARE_PLATFORM(firestone) = {
 	.start_preload_resource	= flash_start_preload_resource,
 	.resource_loaded	= flash_resource_loaded,
 	.exit			= ipmi_wdt_final_reset,
+	.terminate		= ipmi_terminate,
 };
diff --git a/platforms/astbmc/garrison.c b/platforms/astbmc/garrison.c
index 5cd8e2e..edc3522 100644
--- a/platforms/astbmc/garrison.c
+++ b/platforms/astbmc/garrison.c
@@ -56,4 +56,5 @@ DECLARE_PLATFORM(garrison) = {
 	.start_preload_resource	= flash_start_preload_resource,
 	.resource_loaded	= flash_resource_loaded,
 	.exit			= ipmi_wdt_final_reset,
+	.terminate		= ipmi_terminate,
 };
diff --git a/platforms/astbmc/habanero.c b/platforms/astbmc/habanero.c
index 41e84f7..4ab2cdc 100644
--- a/platforms/astbmc/habanero.c
+++ b/platforms/astbmc/habanero.c
@@ -153,4 +153,5 @@ DECLARE_PLATFORM(habanero) = {
 	.start_preload_resource	= flash_start_preload_resource,
 	.resource_loaded	= flash_resource_loaded,
 	.exit			= ipmi_wdt_final_reset,
+	.terminate		= ipmi_terminate,
 };
diff --git a/platforms/astbmc/palmetto.c b/platforms/astbmc/palmetto.c
index 7c2a157..ca91908 100644
--- a/platforms/astbmc/palmetto.c
+++ b/platforms/astbmc/palmetto.c
@@ -56,4 +56,5 @@ DECLARE_PLATFORM(palmetto) = {
 	.start_preload_resource	= flash_start_preload_resource,
 	.resource_loaded	= flash_resource_loaded,
 	.exit			= ipmi_wdt_final_reset,
+	.terminate		= ipmi_terminate,
 };