From 0a89d5237edcec3015363e9a7a3bd8b014fec500 Mon Sep 17 00:00:00 2001 From: Sergii Dmytruk Date: Sat, 29 Oct 2022 16:57:07 +0300 Subject: security/tpm: remove tis_close() This function was never called from outside of drivers and src/drivers/pc80/tpm/tis.c was the only one doing it in a questionable way. tpm_vendor_cleanup() also isn't needed as one of tis_close() functions was its only caller. Change-Id: I9df76adfc21fca9fa1d1af7c40635ec0684ceb0f Ticket: https://ticket.coreboot.org/issues/433 Signed-off-by: Sergii Dmytruk Reviewed-on: https://review.coreboot.org/c/coreboot/+/68989 Tested-by: build bot (Jenkins) Reviewed-by: Julius Werner --- src/drivers/pc80/tpm/tis.c | 66 ++++++++++------------------------------------ 1 file changed, 14 insertions(+), 52 deletions(-) (limited to 'src/drivers/pc80') diff --git a/src/drivers/pc80/tpm/tis.c b/src/drivers/pc80/tpm/tis.c index 06f543498f..ce88ae012d 100644 --- a/src/drivers/pc80/tpm/tis.c +++ b/src/drivers/pc80/tpm/tis.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -316,11 +317,6 @@ static int tis_wait_access(int locality, u8 mask, u8 expected) return TPM_TIMEOUT_ERR; } -static inline int tis_wait_dropped_access(int locality) -{ - return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, 0); -} - static inline int tis_wait_received_access(int locality) { return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, @@ -337,11 +333,6 @@ static inline void tis_request_access(int locality) tpm_write_access(TIS_ACCESS_REQUEST_USE, locality); } -static inline void tis_drop_access(int locality) -{ - tpm_write_access(TIS_ACCESS_ACTIVE_LOCALITY, locality); -} - /* * PC Client Specific TPM Interface Specification section 11.2.12: * @@ -632,8 +623,7 @@ int tis_init(void) /* * tis_open() * - * Requests access to locality 0 for the caller. After all commands have been - * completed the caller is supposed to call tis_close(). + * Requests access to locality 0 for the caller. * * Returns 0 on success, TPM_DRIVER_ERR on failure. */ @@ -641,49 +631,27 @@ int tis_open(void) { u8 locality = 0; /* we use locality zero for everything */ - if (tis_close()) - return TPM_DRIVER_ERR; + if (!tis_has_access(locality)) { + /* request access to locality */ + tis_request_access(locality); - /* now request access to locality */ - tis_request_access(locality); + /* did we get a lock? */ + if (tis_wait_received_access(locality)) { + printf("%s:%d - failed to lock locality %u\n", + __FILE__, __LINE__, locality); + return TPM_DRIVER_ERR; + } - /* did we get a lock? */ - if (tis_wait_received_access(locality)) { - printf("%s:%d - failed to lock locality %u\n", - __FILE__, __LINE__, locality); - return TPM_DRIVER_ERR; + /* Certain TPMs seem to need some delay here or they hang... */ + udelay(10); } - /* Certain TPMs seem to need some delay here or they hang... */ - udelay(10); - if (tis_command_ready(locality) == TPM_TIMEOUT_ERR) return TPM_DRIVER_ERR; return 0; } -/* - * tis_close() - * - * terminate the current session with the TPM by releasing the locked - * locality. Returns 0 on success of TPM_DRIVER_ERR on failure (in case lock - * removal did not succeed). - */ -int tis_close(void) -{ - u8 locality = 0; - if (tis_has_access(locality)) { - tis_drop_access(locality); - if (tis_wait_dropped_access(locality)) { - printf("%s:%d - failed to release locality %u\n", - __FILE__, __LINE__, locality); - return TPM_DRIVER_ERR; - } - } - return 0; -} - /* * tis_sendrecv() * @@ -727,10 +695,8 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t send_size, static int tis_setup_interrupt(int vector, int polarity) { u8 locality = 0; - int has_access = tis_has_access(locality); - /* Open connection and request access if not already granted */ - if (!has_access && tis_open() < 0) + if (tlcl_lib_init()) return TPM_DRIVER_ERR; /* Set TPM interrupt vector */ @@ -739,10 +705,6 @@ static int tis_setup_interrupt(int vector, int polarity) /* Set TPM interrupt polarity and disable interrupts */ tpm_write_int_polarity(polarity, locality); - /* Close connection if it was opened */ - if (!has_access && tis_close() < 0) - return TPM_DRIVER_ERR; - return 0; } -- cgit v1.2.3