diff options
| author | Scott <scollyer@chromium.org> | 2016-09-21 14:34:01 -0700 |
|---|---|---|
| committer | chrome-bot <chrome-bot@chromium.org> | 2016-09-25 17:47:29 -0700 |
| commit | 672ea89dba35644d5a6b056c5e6a6ffa37dfca11 (patch) | |
| tree | ca19b6275f770aa1a996c3ace7cc8cebdb6f3d81 /common/i2cs_tpm.c | |
| parent | 66ad05dfd7751f0351fce39e923da5523c08f261 (diff) | |
| download | chrome-ec-stabilize-8838.B.tar.gz | |
Cr50: I2CS TPM: Prevent sleep when I2CS is activestabilize-8838.B
Similar to the TPM SPI interface, added code to disable sleep an I2CS
interrupt is received. Enabling sleep follwoing a 1 second delay when
the TPM fifo register has been read by the host. The I2CS TPM layer
doesn't know when a command has finished, but the one second delay is
more than enough delay since sleep will be disabled again when the
next I2CS interrupt is received.
BRANCH=none
BUG=chrome-os-partner:40397
TEST=manual
Tested without these changes first. Shortened sleep delay to 30
seconds, and disconnected suzyq. Waited 30 seconds then issued the
command on the AP console:
tpmc read 0x1007 0xa
[ 59.796813] tpm tpm0: tpm_transmit: tpm_send: error -16
ERROR: write failure to TPM device: Device or resource busy
In addition, using logic analyzer verifed that there was activity on
SDA/SCL but no response from Cr50. With this CL in place, ran the
test and got the following:
tpmc read 0x1007 0xa
2 0 1 0 1 0 0 0 0 4f
With the logic analyzer I was able to confirm that there was no
activity from the host on the I2CS bus until the command was issued.
Change-Id: If07573ae8f72b983bca57979d53c22660b91b95e
Signed-off-by: Scott <scollyer@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/387910
Commit-Ready: Scott Collyer <scollyer@chromium.org>
Tested-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Mary Ruthven <mruthven@chromium.org>
Diffstat (limited to 'common/i2cs_tpm.c')
| -rw-r--r-- | common/i2cs_tpm.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/common/i2cs_tpm.c b/common/i2cs_tpm.c index b9ab003b16..7700fd8373 100644 --- a/common/i2cs_tpm.c +++ b/common/i2cs_tpm.c @@ -9,6 +9,7 @@ #include "hooks.h" #include "i2cs.h" #include "registers.h" +#include "system.h" #include "tpm_registers.h" /* @@ -129,6 +130,14 @@ static void process_read_access(uint16_t reg_size, tpm_register_get(tpm_reg, data, reg_size); /* Transfer TPM fifo data to the I2CS HW fifo */ i2cs_post_read_fill_fifo(data, reg_size); + + /* + * Could be the end of a TPM trasaction. Set sleep to be reenabled in 1 + * second. If this is not the end of a TPM response, then sleep will be + * disabled again in the next I2CS interrupt. + */ + delay_sleep_by(1 * SECOND); + enable_sleep(SLEEP_MASK_I2C_SLAVE); } static void process_write_access(uint16_t reg_size, uint16_t tpm_reg, |