mb/google/nissa: Change TPM I2C freqeuncy to 1 MHz
Change the TPM I2C freqeuncy to 1 MHz for nivviks and nereid, and in
the baseboard. Other nissa devices will be changed after verification.
This saves 11 ms of boot time on nivviks and nereid.
400 kHz:
504:finished TPM initialization 272,304 (35,730)
...
512:finished TPM PCR extend 526,250 (23,729)
513:starting locking TPM 526,250 (0)
514:finished locking TPM 535,106 (8,855)
6:end of verified boot 543,927 (8,821)
1 MHz:
504:finished TPM initialization 266,293 (30,747)
...
512:finished TPM PCR extend 513,711 (20,108)
513:starting locking TPM 513,711 (0)
514:finished locking TPM 521,311 (7,599)
6:end of verified boot 528,893 (7,581)
BUG=b:249201598
TEST=On nivviks and nereid, all timing requirements in the spec are met.
Frequencies:
nivviks - 972.01 kHz
nereid - 968.99 kHz
Change-Id: I9dd783527d4215ed7d79d69853a1f321ea2d8a28
Signed-off-by: Reka Norman <rekanorman@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67942
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kangheui Won <khwon@chromium.org>
diff --git a/src/mainboard/google/brya/variants/nivviks/overridetree.cb b/src/mainboard/google/brya/variants/nivviks/overridetree.cb
index f8c5ef4..76fe43e 100644
--- a/src/mainboard/google/brya/variants/nivviks/overridetree.cb
+++ b/src/mainboard/google/brya/variants/nivviks/overridetree.cb
@@ -72,11 +72,11 @@
register "common_soc_config" = "{
.i2c[0] = {
.early_init = 1,
- .speed = I2C_SPEED_FAST,
+ .speed = I2C_SPEED_FAST_PLUS,
.speed_config[0] = {
- .speed = I2C_SPEED_FAST,
- .scl_lcnt = 160,
- .scl_hcnt = 79,
+ .speed = I2C_SPEED_FAST_PLUS,
+ .scl_lcnt = 55,
+ .scl_hcnt = 30,
.sda_hold = 7,
}
},