From 6de7ecb585e705beab32e7464d364f2284ccae54 Mon Sep 17 00:00:00 2001
From: David Wu <david_wu@quanta.corp-partner.google.com>
Date: Thu, 19 Dec 2019 17:20:53 +0800
Subject: mb/google/hatch/var/kindred: Decrease i2c frequency below 400 KHz

Before tuning i2c frequency,
I2C0: 479.4 KHz
I2C1: 491.4 KHz
I2C4: 476.4 KHz

After tuning i2c frequency,
I2C0: 391.8 KHz
I2C1: 396.4 KHz
I2C4: 388.8 KHz

BUG=b:146535585
BRANCH=hatch
TEST=emerge-hatch coreboot chromeos-bootimage

Change-Id: I55d095efb60eba4e860b54bb90e8e0df62d88419
Signed-off-by: David Wu <david_wu@quanta.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37831
Reviewed-by: Philip Chen <philipchen@google.com>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
---
 src/mainboard/google/hatch/variants/kindred/overridetree.cb | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'src/mainboard/google')

diff --git a/src/mainboard/google/hatch/variants/kindred/overridetree.cb b/src/mainboard/google/hatch/variants/kindred/overridetree.cb
index 1122609649..a000add5b0 100644
--- a/src/mainboard/google/hatch/variants/kindred/overridetree.cb
+++ b/src/mainboard/google/hatch/variants/kindred/overridetree.cb
@@ -36,12 +36,18 @@ chip soc/intel/cannonlake
 		},
 		.i2c[0] = {
 			.speed = I2C_SPEED_FAST,
+			.rise_time_ns = 50,
+			.fall_time_ns = 15,
 		},
 		.i2c[1] = {
 			.speed = I2C_SPEED_FAST,
+			.rise_time_ns = 60,
+			.fall_time_ns = 25,
 		},
 		.i2c[4] = {
 			.speed = I2C_SPEED_FAST,
+			.rise_time_ns = 60,
+			.fall_time_ns = 60,
 		},
 	}"
 
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