[coreboot-gerrit] Change in coreboot[master]: timestamps: Fix syncing, logging and comments

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/coreboot/+/38301 )

Change subject: timestamps: Fix syncing, logging and comments
......................................................................

timestamps: Fix syncing, logging and comments

For timestamps added before CBMEM coming online and call to
timestamp_sync_cache_to_cbmem(), ts_table->base_time was
subtracted twice. The second time though, the value of zero
was subtracted.

Make the stamps logged on the console relative to base_time too,
such that cbmem -1 and cbmem -c outputs will match.

Remove comments about postponing initialisation of timestamps
to ramstage, that does not happen anymore.

Change-Id: Ia786c12c68c8921c0d09bc58a29fefdc72bf0c6d
Signed-off-by: Kyösti Mälkki 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38301
Tested-by: build bot (Jenkins) 
Reviewed-by: Paul Menzel 
Reviewed-by: Martin Roth 
Reviewed-by: Nico Huber 
---
M src/lib/timestamp.c
1 file changed, 6 insertions(+), 9 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Martin Roth: Looks good to me, approved
  Nico Huber: Looks good to me, approved
  Paul Menzel: Looks good to me, but someone else must approve

diff --git a/src/lib/timestamp.c b/src/lib/timestamp.c
index d2206f6..9cbe308 100644
--- a/src/lib/timestamp.c
+++ b/src/lib/timestamp.c
@@ -128,7 +128,7 @@

tse = &ts_table->entries[ts_table->num_entries++];
    tse->entry_id = id;
-	tse->entry_stamp = ts_time - ts_table->base_time;
+	tse->entry_stamp = ts_time;

if (ts_table->num_entries == ts_table->max_entries)
    	printk(BIOS_ERR, "ERROR: Timestamp table full\n");
@@ -148,6 +148,7 @@
    	return;
    }

+	ts_time -= ts_table->base_time;
    timestamp_add_table_entry(ts_table, id, ts_time);

if (CONFIG(TIMESTAMPS_ON_CONSOLE))
@@ -206,22 +207,18 @@
     *
     * If you try to initialize timestamps before ramstage but don't define
     * a TIMESTAMP region, all operations will fail (safely), and coreboot
-	 * will behave as if timestamps only get initialized in ramstage.
-	 *
-	 * If timestamps only get initialized in ramstage, the base_time from
-	 * timestamp_init() will get ignored and all timestamps will be 0-based.
+	 * will behave as if timestamps collection was disabled.
     */

+	/* Inherit cache base_time. */
+	ts_cbmem_table->base_time = ts_cache_table->base_time;
+
    for (i = 0; i < ts_cache_table->num_entries; i++) {
    	struct timestamp_entry *tse = &ts_cache_table->entries[i];
    	timestamp_add_table_entry(ts_cbmem_table, tse->entry_id,
    				  tse->entry_stamp);
    }

-	/* Freshly added cbmem table has base_time 0. Inherit cache base_time */
-	if (ts_cbmem_table->base_time == 0)
-		ts_cbmem_table->base_time = ts_cache_table->base_time;
-
    /* Cache no longer required. */
    ts_cache_table->num_entries = 0;
 }