Furquan Shaikh has uploaded this change for review. ( https://review.coreboot.org/21208
Change subject: mainboard/google/poppy: Tune I2C params (hcnt, lcnt, hold time) ......................................................................
mainboard/google/poppy: Tune I2C params (hcnt, lcnt, hold time)
Tune I2C params for I2C buses 0, 1, 2, 4 and 5 to ensure that the frequency does not exceed 400KHz.
BUG=b:35948024 TEST=Verified for 25 iterations that the frequency on each bus ranges <= 400KHz.
I2C0: 375 - 400 I2C1: 377 - 400 I2C2: 377 - 400 I2C4: 375 - 397 I2C5: 375 - 397
Change-Id: Ie30e1a12b66c4660b648a585c4dfd66faf004129 Signed-off-by: Furquan Shaikh furquan@chromium.org --- M src/mainboard/google/poppy/variants/baseboard/devicetree.cb 1 file changed, 66 insertions(+), 12 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/08/21208/1
diff --git a/src/mainboard/google/poppy/variants/baseboard/devicetree.cb b/src/mainboard/google/poppy/variants/baseboard/devicetree.cb index 2324557..d4f8fde 100644 --- a/src/mainboard/google/poppy/variants/baseboard/devicetree.cb +++ b/src/mainboard/google/poppy/variants/baseboard/devicetree.cb @@ -165,23 +165,77 @@ register "usb3_ports[2]" = "USB3_PORT_DEFAULT(OC_SKIP)" # Type-A Port register "usb3_ports[3]" = "USB3_PORT_EMPTY" # Empty
- register "i2c_voltage[0]" = "I2C_VOLTAGE_3V3" # Touchscreen - register "i2c_voltage[1]" = "I2C_VOLTAGE_3V3" # H1 - register "i2c_voltage[2]" = "I2C_VOLTAGE_1V8" # Camera - register "i2c_voltage[3]" = "I2C_VOLTAGE_1V8" # Pen - register "i2c_voltage[4]" = "I2C_VOLTAGE_1V8" # Camera - register "i2c_voltage[5]" = "I2C_VOLTAGE_1V8" # Audio + # Touchscreen + register "i2c_voltage[0]" = "I2C_VOLTAGE_3V3" + register "i2c[0]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 185, + .scl_hcnt = 90, + .sda_hold = 36, + }, + }" + + # H1 + + register "i2c_voltage[1]" = "I2C_VOLTAGE_3V3" + register "i2c[1]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 190, + .scl_hcnt = 100, + .sda_hold = 36, + }, + .early_init = 1, + }" + + + # Camera + register "i2c_voltage[2]" = "I2C_VOLTAGE_1V8" + register "i2c[2]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 190, + .scl_hcnt = 97, + .sda_hold = 36, + }, + }" + + # Pen + register "i2c_voltage[3]" = "I2C_VOLTAGE_1V8" + + # Camera + register "i2c_voltage[4]" = "I2C_VOLTAGE_1V8" + register "i2c[4]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 190, + .scl_hcnt = 97, + .sda_hold = 36, + }, + }" + + # Audio + register "i2c_voltage[5]" = "I2C_VOLTAGE_1V8" + register "i2c[5]" = "{ + .speed = I2C_SPEED_FAST, + .speed_config[0] = { + .speed = I2C_SPEED_FAST, + .scl_lcnt = 190, + .scl_hcnt = 98, + .sda_hold = 36, + }, + }" +
# Use GSPI0 for cr50 TPM. Early init is required to set up a BAR for TPM # communication before memory is up. register "gspi[0]" = "{ .speed_mhz = 1, - .early_init = 1, - }" - - # Configure I2C1 for cr50 TPM. Early init is required to set up a BAR - # for TPM communication before memory is up. - register "i2c[1]" = "{ .early_init = 1, }"