[PATCH v4 14/14] tpm: Allow locality 2 to be set when initializing the TPM for Secure Launch

From: Ross Philipson
Date: Fri Aug 27 2021 - 09:21:56 EST


The Secure Launch MLE environment uses PCRs that are only accessible from
the DRTM locality 2. By default the TPM drivers always initialize the
locality to 0. When a Secure Launch is in progress, initialize the
locality to 2.

Signed-off-by: Ross Philipson <ross.philipson@xxxxxxxxxx>
---
drivers/char/tpm/tpm-chip.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index ddaeceb..ce0a3b7 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -23,6 +23,7 @@
#include <linux/major.h>
#include <linux/tpm_eventlog.h>
#include <linux/hw_random.h>
+#include <linux/slaunch.h>
#include "tpm.h"

DEFINE_IDR(dev_nums_idr);
@@ -34,12 +35,18 @@

static int tpm_request_locality(struct tpm_chip *chip)
{
+ int locality;
int rc;

if (!chip->ops->request_locality)
return 0;

- rc = chip->ops->request_locality(chip, 0);
+ if (slaunch_get_flags() & SL_FLAG_ACTIVE)
+ locality = 2;
+ else
+ locality = 0;
+
+ rc = chip->ops->request_locality(chip, locality);
if (rc < 0)
return rc;

--
1.8.3.1