fsp/elog: Create a logging frontend

In order to support fsp-less machines we need to be able to log errors
using a BMC or some other mechanism. Currently the error logging code
is tightly coupled to the platform making it difficult to add
different platforms.

This patch factors out the generic parts of the error logging code in
preparation for adding different logging backends. It also adds a
generic mechanism for pre-allocating a specific number of objects.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

1 files changed, 176 insertions, 0 deletions

diff --git a/core/errorlog.c b/core/errorlog.c
new file mode 100644
index 0000000..8867a8e
--- /dev/null
+++ b/core/errorlog.c
@@ -0,0 +1,176 @@
+/* Copyright 2013-2014 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.
+ */
+
+/* This file contains the front end for OPAL error logging. It is used
+ * to construct a struct errorlog representing the event/error to be
+ * logged which is then passed to the platform specific backend to log
+ * the actual errors.
+ */
+#include <skiboot.h>
+#include <lock.h>
+#include <errorlog.h>
+#include <fsp-elog.h>
+#include <pool.h>
+
+/*
+ * Maximum number buffers that are pre-allocated
+ * to hold elogs that are reported on Sapphire and
+ * powernv.
+ */
+#define ELOG_WRITE_MAX_RECORD		64
+
+/* Platform Log ID as per the spec */
+static uint32_t sapphire_elog_id = 0xB0000000;
+/* Reserved for future use */
+/* static uint32_t powernv_elog_id = 0xB1000000; */
+
+/* Pool to allocate elog messages from */
+static struct pool elog_pool;
+static struct lock elog_lock = LOCK_UNLOCKED;
+
+static struct errorlog *get_write_buffer(int opal_event_severity)
+{
+	struct errorlog *buf;
+
+	lock(&elog_lock);
+	if (opal_event_severity == OPAL_ERROR_PANIC)
+		buf = pool_get(&elog_pool, POOL_HIGH);
+	else
+		buf = pool_get(&elog_pool, POOL_NORMAL);
+	unlock(&elog_lock);
+	return buf;
+}
+
+int opal_elog_update_user_dump(struct errorlog *buf, unsigned char *data,
+					      uint32_t tag, uint16_t size)
+{
+	char *buffer;
+	struct elog_user_data_section *tmp;
+
+	if (!buf) {
+		prerror("ELOG: Cannot update user data. Buffer is invalid\n");
+		return -1;
+	}
+
+	buffer = (char *)buf->user_data_dump + buf->user_section_size;
+	if ((buf->user_section_size + size) > OPAL_LOG_MAX_DUMP) {
+		prerror("ELOG: Size of dump data overruns buffer\n");
+		return -1;
+	}
+
+	tmp = (struct elog_user_data_section *)buffer;
+	tmp->tag = tag;
+	tmp->size = size + sizeof(struct elog_user_data_section) - 1;
+	memcpy(tmp->data_dump, data, size);
+
+	buf->user_section_size += tmp->size;
+	buf->user_section_count++;
+	return 0;
+}
+
+/* Reporting of error via struct errorlog */
+struct errorlog *opal_elog_create(struct opal_err_info *e_info)
+{
+	struct errorlog *buf;
+
+	buf = get_write_buffer(e_info->sev);
+	if (buf) {
+		buf->error_event_type = e_info->err_type;
+		buf->component_id = e_info->cmp_id;
+		buf->subsystem_id = e_info->subsystem;
+		buf->event_severity = e_info->sev;
+		buf->event_subtype = e_info->event_subtype;
+		buf->reason_code = e_info->reason_code;
+		buf->elog_origin = ORG_SAPPHIRE;
+
+		lock(&elog_lock);
+		buf->plid = ++sapphire_elog_id;
+		unlock(&elog_lock);
+	}
+
+	return buf;
+}
+
+void opal_elog_complete(struct errorlog *buf, bool success)
+{
+	if (!success)
+		printf("Unable to log error\n");
+
+	lock(&elog_lock);
+	pool_free_object(&elog_pool, buf);
+	unlock(&elog_lock);
+}
+
+void log_error(struct opal_err_info *e_info, void *data, uint16_t size,
+	       const char *fmt, ...)
+{
+	struct errorlog *buf;
+	int tag = 0x44455343;  /* ASCII of DESC */
+	va_list list;
+	char err_msg[250];
+
+	va_start(list, fmt);
+	vsnprintf(err_msg, sizeof(err_msg), fmt, list);
+	va_end(list);
+
+	/* Log the error on to Sapphire console */
+	prerror("%s", err_msg);
+
+	buf = opal_elog_create(e_info);
+	if (buf == NULL)
+		prerror("ELOG: Error getting buffer to log error\n");
+	else {
+		opal_elog_update_user_dump(buf, err_msg, tag, strlen(err_msg));
+		/* Append any number of call out dumps */
+		if (e_info->call_out)
+			e_info->call_out(buf, data, size);
+		if (elog_fsp_commit(buf))
+			prerror("ELOG: Re-try error logging\n");
+	}
+}
+
+void log_simple_error(struct opal_err_info *e_info, const char *fmt, ...)
+{
+	struct errorlog *buf;
+	int tag = 0x44455343;  /* ASCII of DESC */
+	va_list list;
+	char err_msg[250];
+
+	va_start(list, fmt);
+	vsnprintf(err_msg, sizeof(err_msg), fmt, list);
+	va_end(list);
+
+	/* Log the error on to Sapphire console */
+	prerror("%s", err_msg);
+
+	buf = opal_elog_create(e_info);
+	if (buf == NULL)
+		prerror("ELOG: Error getting buffer to log error\n");
+	else {
+		opal_elog_update_user_dump(buf, err_msg, tag, strlen(err_msg));
+		if (elog_fsp_commit(buf))
+			prerror("ELOG: Re-try error logging\n");
+	}
+}
+
+int elog_init(void)
+{
+	/* pre-allocate memory for records */
+	if (pool_init(&elog_pool, sizeof(struct errorlog), ELOG_WRITE_MAX_RECORD, 1))
+		return OPAL_RESOURCE;
+
+	return 0;
+}