brdprop: log invalid and ambiguous events

Log brdprop errors in flog, so the team can track brdprop errors from
the AP without grepping through cr50 logs.

BUG=b:214550629
TEST=flash on red board. Verify invalid strap events are logged.
     enable closed-loop-reset on the red board. Verify "ambiguous" strap
     logs are ignored.

Change-Id: Ibea73fb19119fa81ed3652c5d68e430cdbae9fa5
Signed-off-by: Mary Ruthven <mruthven@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3386405
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Commit-Queue: Vadim Bendebury <vbendeb@chromium.org>

3 files changed, 69 insertions, 1 deletions

diff --git a/board/cr50/board.c b/board/cr50/board.c
index 3cf0156c26..cfe2d9a4d7 100644
--- a/board/cr50/board.c
+++ b/board/cr50/board.c
@@ -828,6 +828,46 @@ static void maybe_trigger_ite_sync(void)
 	generate_ite_sync();
 }
 
+/*
+ * Save the logged events, the system reset flags, and the config for the
+ * event in flog.
+ */
+static struct brdprop_payload bp_flog;
+
+/* Each event can be logged once per boot. */
+static void flog_brdprop_event(enum brdprop_ev event, uint8_t config)
+{
+	if (event >= BRDPROP_COUNT) {
+		CPRINTS("%s: invalid event %d", __func__, event);
+		return;
+	}
+	bp_flog.events |= (1 << event);
+	bp_flog.configs[event] = config;
+}
+
+/*
+ * The flog isn't initialized when board properties are calculated. Save the
+ * information in flog once it's ready.
+ */
+static void process_brdprop_flog(void)
+{
+	if (!bp_flog.events)
+		return;
+	/*
+	 * Boards with closed loop reset are going to have ambiguous straps
+	 * after reboot. Don't log those errors. Only log invalid strap errors
+	 * on those boards.
+	 * Filter these here, because cr50 doesn't know the board properties
+	 * when it's initially logging the errors.
+	 */
+	if (board_uses_closed_loop_reset() &&
+	    bp_flog.events == (1 << BRDPROP_AMBIGUOUS))
+		return;
+
+	bp_flog.reset_flags = system_get_reset_flags();
+	flash_log_add_event(FE_LOG_BRDPROP, sizeof(bp_flog), &bp_flog);
+}
+
 static void process_board_cfg(void)
 {
 	uint32_t tpm_board_cfg = board_cfg_reg_read();
@@ -874,6 +914,9 @@ static void board_init(void)
 	 */
 	if (system_get_reset_flags() & EC_RESET_FLAG_HIBERNATE)
 		system_decrement_retry_counter();
+
+	process_brdprop_flog();
+
 	configure_board_specific_gpios();
 	init_pmu();
 	reset_wake_logic();
@@ -1519,6 +1562,7 @@ static int get_strap_config(uint8_t *config)
 	 * unused config pins the AP is interfering with.
 	 */
 	if (use_i2c && use_spi) {
+		flog_brdprop_event(BRDPROP_AMBIGUOUS, *config);
 		spi_prop = (GREG32(PMU, LONG_LIFE_SCRATCH1) &
 			    BOARD_PERIPH_CONFIG_SPI);
 		i2c_prop = (GREG32(PMU, LONG_LIFE_SCRATCH1) &
@@ -1544,6 +1588,7 @@ static uint32_t get_properties(void)
 	uint32_t properties;
 
 	if (get_strap_config(&config) != EC_SUCCESS) {
+		flog_brdprop_event(BRDPROP_INVALID, config);
 #ifdef H1_RED_BOARD
 		CPRINTS("Unconditionally enabling SPI and platform reset");
 		return (BOARD_PERIPH_CONFIG_SPI | BOARD_USE_PLT_RESET);
@@ -1586,6 +1631,7 @@ static uint32_t get_properties(void)
 		/* All I2C boards use same default properties. */
 		properties = BOARD_PROPERTIES_DEFAULT;
 	}
+	flog_brdprop_event(BRDPROP_NO_ENTRY, config);
 	CPRINTS("strap_cfg 0x%x has no table entry, prop = 0x%x",
 		config, properties);
 	return properties;
diff --git a/common/flash_log.c b/common/flash_log.c
index 798f48a2a6..927c7ac3f7 100644
--- a/common/flash_log.c
+++ b/common/flash_log.c
@@ -486,7 +486,7 @@ test_export_static void flash_log_init(void)
 	}
 	flash_log_write_disable();
 }
-DECLARE_HOOK(HOOK_INIT, flash_log_init, HOOK_PRIO_DEFAULT);
+DECLARE_HOOK(HOOK_INIT, flash_log_init, HOOK_PRIO_INIT_CR50_BOARD - 1);
 
 uint32_t flash_log_get_tstamp(void)
 {
diff --git a/include/flash_log.h b/include/flash_log.h
index cc6c292d49..30bd326712 100644
--- a/include/flash_log.h
+++ b/include/flash_log.h
@@ -25,6 +25,7 @@ enum flash_event_type {
 	FE_LOG_FIPS_FAILURE = 10, /* Error during continuous and/or known-answer
 				   * tests for FIPS 140-2/3
 				   */
+	FE_LOG_BRDPROP = 11, /* Detected invalid board properties */
 	/*
 	 * Fixed padding value makes it easier to parse log space
 	 * snapshots.
@@ -106,6 +107,27 @@ struct ap_ro_entry_payload {
 	enum ap_ro_verification_ev event : 8;
 } __packed;
 
+/*****************************************************************************/
+/* Brdprop Events */
+/* Each event can only be logged once per boot. */
+enum brdprop_ev {
+	BRDPROP_INVALID = 0,
+	BRDPROP_AMBIGUOUS = 1,
+	BRDPROP_NO_ENTRY = 2,
+
+	/*
+	 * If BRDPROP_COUNT goes above 8, increase the size of events in
+	 * brdprop_payload.
+	 */
+	BRDPROP_COUNT = 3,
+};
+
+struct brdprop_payload {
+	uint8_t events;
+	uint32_t reset_flags;
+	uint8_t configs[BRDPROP_COUNT];
+} __packed;
+
 /* Returned in the "type" field, when there is no entry available */
 #define FLASH_LOG_NO_ENTRY 0xff
 #define MAX_FLASH_LOG_PAYLOAD_SIZE ((1 << 6) - 1)