Add timestamp collecting to coreboot.

This patch adds code to initialize the time stamp collection
facility in coreboot. It adds a table in the CBMEM section, which
provides the base timer reading value (all other readings are
offsets of this one) and an array of timestamp id/timestamp value
pairs.

Just two values are being added now, this will have to be used
more extensively and also integrated into payloads to provide more
comprehensive boot process time measurements.

Also, since the CBMEM area could already contain a section (from the
previous run, before reset), when processing a section addition
request we should check if a section already exists and return its
address, if so.

Change-Id: I7ed9f5c400bc5432f228348b41fd19a67c36d533
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: http://review.coreboot.org/713
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)

src/include/cbmem.h

@@ -41,6 +41,7 @@ extern uint64_t high_tables_base, high_tables_size;
 #define CBMEM_ID_MPTABLE	0x534d5054
 #define CBMEM_ID_RESUME		0x5245534d
 #define CBMEM_ID_SMBIOS         0x534d4254
+#define CBMEM_ID_TIMESTAMP	0x54494d45
 #define CBMEM_ID_NONE		0x00000000
 
 int cbmem_initialize(void);

src/include/timestamp.h

@@ -0,0 +1,46 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2011 The ChromiumOS Authors.  All rights reserved.
+ *
+ * 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; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
+ */
+
+#ifndef __TIMESTAMP_H__
+#define __TIMESTAMP_H__
+
+#include <cpu/x86/tsc.h>
+
+struct timestamp_entry {
+	uint32_t	entry_id;
+	uint64_t	entry_stamp;
+} __attribute__((packed));
+
+struct timestamp_table {
+	uint64_t	base_time;
+	uint32_t	max_entries;
+	uint32_t	num_entries;
+	struct timestamp_entry entries[0]; /* Variable number of entries */
+} __attribute__((packed));
+
+enum timestamp_id {
+	TS_BEFORE_INITRAM = 1,
+	TS_AFTER_INITRAM = 2,
+};
+
+void timestamp_init(tsc_t base);
+void timestamp_add(enum timestamp_id id, tsc_t ts_time);
+void timestamp_add_now(enum timestamp_id id);
+
+#endif

src/lib/Makefile.inc

@@ -14,6 +14,7 @@ romstage-$(CONFIG_CONSOLE_SERIAL8250MEM) += uart8250mem.c
 romstage-$(CONFIG_CONSOLE_NE2K) += ne2k.c
 romstage-$(CONFIG_CONSOLE_NE2K) += compute_ip_checksum.c
 romstage-$(CONFIG_USBDEBUG) += usbdebug.c
+romstage-$(CONFIG_COLLECT_TIMESTAMPS) += timestamp.c
 
 ramstage-y += memset.c
 ramstage-y += memchr.c
@@ -36,6 +37,7 @@ ramstage-$(CONFIG_CONSOLE_SERIAL8250MEM) += uart8250mem.c
 ramstage-$(CONFIG_USBDEBUG) += usbdebug.c
 ramstage-$(CONFIG_BOOTSPLASH) += jpeg.c
 ramstage-$(CONFIG_TRACE) += trace.c
+ramstage-$(CONFIG_COLLECT_TIMESTAMPS) += timestamp.c
 
 driver-$(CONFIG_CONSOLE_NE2K) += ne2k.c
 

src/lib/cbmem.c

@@ -118,6 +118,22 @@ void *cbmem_add(u32 id, u64 size)
 {
 	struct cbmem_entry *cbmem_toc;
 	int i;
+	void *p;
+
+	/*
+	 * This could be a restart, check if the section is there already. It
+	 * is remotely possible that the dram contents persisted over the
+	 * bootloader upgrade AND the same section now needs more room, but
+	 * this is quite a remote possibility and it is ignored here.
+	 */
+	p = cbmem_find(id);
+	if (p) {
+		printk(BIOS_NOTICE,
+		       "CBMEM section %x: using existing location at %p.\n",
+		       id, p);
+		return p;
+	}
+
 	cbmem_toc = get_cbmem_toc();
 
 	if (cbmem_toc == NULL) {
@@ -240,6 +256,7 @@ void cbmem_list(void)
 		case CBMEM_ID_MPTABLE:	 printk(BIOS_DEBUG, "SMP TABLE  "); break;
 		case CBMEM_ID_RESUME:	 printk(BIOS_DEBUG, "ACPI RESUME"); break;
 		case CBMEM_ID_SMBIOS:    printk(BIOS_DEBUG, "SMBIOS     "); break;
+		case CBMEM_ID_TIMESTAMP: printk(BIOS_DEBUG, "TIME STAMP "); break;
 		default: printk(BIOS_DEBUG, "%08x ", cbmem_toc[i].id);
 		}
 		printk(BIOS_DEBUG, "%08llx ", cbmem_toc[i].base);

src/lib/timestamp.c

@@ -0,0 +1,74 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2011 The ChromiumOS Authors.  All rights reserved.
+ *
+ * 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; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <console/console.h>
+#include <cbmem.h>
+#include <timestamp.h>
+
+#define MAX_TIMESTAMPS 30
+
+#ifndef __PRE_RAM__
+static struct timestamp_table* ts_table;
+#endif
+
+static uint64_t tsc_to_uint64(tsc_t tstamp)
+{
+	return (((uint64_t)tstamp.hi) << 32) + tstamp.lo;
+}
+
+void timestamp_init(tsc_t base)
+{
+	struct timestamp_table* tst;
+
+	tst = cbmem_add(CBMEM_ID_TIMESTAMP,
+			sizeof(struct timestamp_table) +
+			MAX_TIMESTAMPS * sizeof(struct timestamp_entry));
+
+	if (!tst) {
+		printk(BIOS_ERR, "ERROR: failed to allocate timstamp table\n");
+		return;
+	}
+
+	tst->base_time = tsc_to_uint64(base);
+	tst->max_entries = MAX_TIMESTAMPS;
+	tst->num_entries = 0;
+}
+
+void timestamp_add(enum timestamp_id id, tsc_t ts_time)
+{
+	struct timestamp_entry *tse;
+#ifdef __PRE_RAM__
+	struct timestamp_table *ts_table = cbmem_find(CBMEM_ID_TIMESTAMP);
+#else
+	if (!ts_table)
+		ts_table = cbmem_find(CBMEM_ID_TIMESTAMP);
+#endif
+	if (!ts_table || (ts_table->num_entries == ts_table->max_entries))
+		return;
+
+	tse = &ts_table->entries[ts_table->num_entries++];
+	tse->entry_id = id;
+	tse->entry_stamp = tsc_to_uint64(ts_time) - ts_table->base_time;
+}
+
+void timestamp_add_now(enum timestamp_id id)
+{
+	timestamp_add(id, rdtsc());
+}