GNUBoot
/
coreboot-kgpe-d16
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mb/google/sarien: Set initial I2C bus rise/fall times 

Provide rise/fall times as measured on existing boards.  This will
need adjusted for new boards but provides a starting point that
makes I2C clocks look reasonable.

Tested by measuring I2C bus speed and rise/fall times with a scope.

Change-Id: Ic18010f5efc41dcee8925d696767ba2c44e3df4b
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/30069
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Lijian Zhao <lijian.zhao@intel.com>
This commit is contained in:
Duncan Laurie 2018-12-05 15:41:03 -08:00 committed by Patrick Georgi
parent 4afefd648b
commit d2226060aa
2 changed files with 8 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/mainboard/google/sarien/variants/arcada/devicetree.cb
View File

@ -67,10 +67,14 @@ chip soc/intel/cannonlake
}, },
.i2c[1] = { .i2c[1] = {
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.rise_time_ns = 216,
.fall_time_ns = 28,
}, },
.i2c[4] = { .i2c[4] = {
.early_init = 1, .early_init = 1,
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.rise_time_ns = 452,
.fall_time_ns = 110,
}, },
}" }"

4
src/mainboard/google/sarien/variants/sarien/devicetree.cb
View File

@ -67,10 +67,14 @@ chip soc/intel/cannonlake
}, },
.i2c[1] = { .i2c[1] = {
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.rise_time_ns = 290,
.fall_time_ns = 110,
}, },
.i2c[4] = { .i2c[4] = {
.early_init = 1, .early_init = 1,
.speed = I2C_SPEED_FAST, .speed = I2C_SPEED_FAST,
.rise_time_ns = 280,
.fall_time_ns = 90,
}, },
}" }"