The branch main has been updated by olivier: URL: https://cgit.FreeBSD.org/src/commit/?id=e4c50d86796d07cf90e6a683234e1c0e9ca5e03c
commit e4c50d86796d07cf90e6a683234e1c0e9ca5e03c Author: Olivier Cochard <[email protected]> AuthorDate: 2026-06-26 19:20:30 +0000 Commit: Olivier Cochard <[email protected]> CommitDate: 2026-06-26 19:56:17 +0000 tpm_tis: release TPM resources after reading response Per TIS 1.3 section 5.6.12, write commandReady to TPM_STS after reading the response so the TPM can free its ReadFIFO and other internal resources. The subsequent tpmtis_go_ready() provides the second write the spec describes and waits for the state transition. PR: 295103 Reported by: Benoit Sansoni <[email protected]> Reviewed by: kevans Approved by: kevans Differential Revision: https://reviews.freebsd.org/D57841 --- sys/dev/tpm/tpm_tis_core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/sys/dev/tpm/tpm_tis_core.c b/sys/dev/tpm/tpm_tis_core.c index f49a1f982e82..95e914fa570b 100644 --- a/sys/dev/tpm/tpm_tis_core.c +++ b/sys/dev/tpm/tpm_tis_core.c @@ -474,6 +474,16 @@ tpmtis_transmit(device_t dev, struct tpm_priv *priv, size_t length) "Failed to read response\n"); return (EIO); } + + /* + * Per TIS 1.3 section 5.6.12, write commandReady after reading the + * response so the TPM can free the ReadFIFO and other internal + * resources. The next tpmtis_go_ready() provides the second + * write the spec mentions, and waits for the state transition, + * so no wait is needed here. + */ + TPM_WRITE_4(sc->dev, TPM_STS, TPM_STS_CMD_RDY); + TPM_WRITE_BARRIER(sc->dev, TPM_STS, 4); tpmtis_relinquish_locality(sc); priv->offset = 0; priv->len = bytes_available;
