[S] Change in coreboot[main]: ec/google/chromeec: Add debug timestamp for host EC commands

[Subrata Banik (Code Review)]

Subrata Banik has submitted this change. ( https://review.coreboot.org/c/coreboot/+/85326?usp=email )

Change subject: ec/google/chromeec: Add debug timestamp for host EC commands
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ec/google/chromeec: Add debug timestamp for host EC commands

Improve host EC command debugging with timestamps and duration for
better analysis, this feature can be enabled by selecting the config
EC_GOOGLE_CHROMEEC_HOST_CMD_DEBUG.

BUG=none
TEST=Brox/lotso device successfully built and booted. Debug messages
confirmed in device logs only when the specific configuration is
selected. Sample print: "EC HOST CMD Duration: 661 us, Command: 0x4b,
version: 0x0"

Change-Id: I8ab89830ede940d2237ad21187b137dca9689fb0
Signed-off-by: Jayvik Desai 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85326
Tested-by: build bot (Jenkins) 
Reviewed-by: Subrata Banik 
---
M src/ec/google/chromeec/Kconfig
M src/ec/google/chromeec/ec_lpc.c
2 files changed, 28 insertions(+), 3 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Subrata Banik: Looks good to me, approved

diff --git a/src/ec/google/chromeec/Kconfig b/src/ec/google/chromeec/Kconfig
index a56565c..a39ac8e 100644
--- a/src/ec/google/chromeec/Kconfig
+++ b/src/ec/google/chromeec/Kconfig
@@ -98,6 +98,12 @@
    help
      Microchip EC variant for LPC register access.

+config EC_GOOGLE_CHROMEEC_EC_HOST_CMD_DEBUG
+	depends on EC_GOOGLE_CHROMEEC_LPC && HAVE_MONOTONIC_TIMER
+	def_bool n
+	help
+	  Enables timestamp and duration logging for host EC commands.
+
 config EC_GOOGLE_CHROMEEC_PD
    def_bool n
    help
diff --git a/src/ec/google/chromeec/ec_lpc.c b/src/ec/google/chromeec/ec_lpc.c
index e661cf5..b86ba7b 100644
--- a/src/ec/google/chromeec/ec_lpc.c
+++ b/src/ec/google/chromeec/ec_lpc.c
@@ -401,17 +401,36 @@
 int google_chromeec_command(struct chromeec_command *cec_command)
 {
    static int command_version;
+	struct stopwatch sw;
+	uint16_t cmd_code;
+	int result = -1;

if (command_version <= 0)
    	command_version = google_chromeec_command_version();

+	if (CONFIG(EC_GOOGLE_CHROMEEC_EC_HOST_CMD_DEBUG)) {
+		cmd_code = cec_command->cmd_code;
+		stopwatch_init(&sw);
+	}
+
    switch (command_version) {
    case EC_HOST_CMD_FLAG_VERSION_3:
-		return google_chromeec_command_v3(cec_command);
+		result = google_chromeec_command_v3(cec_command);
+		break;
    case EC_HOST_CMD_FLAG_LPC_ARGS_SUPPORTED:
-		return google_chromeec_command_v1(cec_command);
+		result = google_chromeec_command_v1(cec_command);
+		break;
    }
-	return -1;
+
+	if (CONFIG(EC_GOOGLE_CHROMEEC_EC_HOST_CMD_DEBUG)) {
+		stopwatch_tick(&sw);
+		printk(BIOS_DEBUG, "EC HOST CMD end Duration: %llu us, Command: 0x%x, Version: 0x%x\n",
+				stopwatch_duration_usecs(&sw),
+				cmd_code,
+				command_version);
+	}
+
+	return result;
 }

static void lpc_ec_init(struct device *dev)