scottk/OpenCellular
1
0
Fork 0
mirror of https://github.com/Telecominfraproject/OpenCellular.git synced 2025-11-25 10:45:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

Implement different strategy for soft-reset workaround on Kaen prototypes.

Browse Source 
BUG=chrome-os-partner:5071
TEST=check that factory flow works on Kaen prototypes without HW fix

Change-Id: I56a830ed292d7e998fa25299f52d22d2faac3c77
Reviewed-on: http://gerrit.chromium.org/gerrit/4533
Tested-by: Luigi Semenzato <semenzato@chromium.org>
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Reviewed-by: Luigi Semenzato <semenzato@chromium.org>
This commit is contained in:
Luigi Semenzato
2011-07-21 17:03:20 -07:00
parent cba0e83d91
commit 1c9577b213
1 changed files with 3 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files

49
firmware/lib/rollback_index.c
View File

@@ -15,10 +15,6 @@
static int g_rollback_recovery_mode = 0;
#ifdef TEGRA_SOFT_REBOOT_WORKAROUND
static int soft_reset = 0;
#endif
/* disable MSVC warning on const logical expression (as in } while(0);) */
__pragma(warning (disable: 4127))
@@ -51,21 +47,6 @@ static uint32_t SafeWrite(uint32_t index, const void* data, uint32_t length) {
if (result == TPM_E_MAXNVWRITES) {
RETURN_ON_FAILURE(TPMClearAndReenable());
return TlclWrite(index, data, length);
#ifdef TEGRA_SOFT_REBOOT_WORKAROUND
} else if ((result == TPM_E_BAD_PRESENCE ||
result == TPM_E_AREA_LOCKED) &&
soft_reset == 1) {
/* Ignore writes that failed because the TPM wasn't unlocked.
*
* This may have security implications. 1. It may delay updating the
* version number, therefore widening the window for a rollback attack.
* 2. It may prevent noticing transitions between developer mode and normal
* mode, in which case the TPM owner will not be cleared when
* transitioning. See crosbug.com/15759. Note that this code path is not
* taken on systems where a CPU reset implies a TPM reset.
*/
return TPM_SUCCESS;
#endif
} else {
return result;
}
@@ -212,11 +193,11 @@ uint32_t SetupTPM(int recovery_mode, int developer_mode,
#ifdef TEGRA_SOFT_REBOOT_WORKAROUND
result = TlclStartup();
if (result == TPM_E_INVALID_POSTINIT) {
/* Some prototype hardware doesn't reset the TPM on a CPU reset. We try to
* tolerate this failure, which is possible in most cases.
/* Some prototype hardware doesn't reset the TPM on a CPU reset. We do a
* hard reset to get around this.
*/
VBDEBUG(("TPM: soft reset detected\n", result));
soft_reset = 1;
return TPM_E_MUST_REBOOT;
} else if (result != TPM_SUCCESS) {
VBDEBUG(("TPM: TlclStartup returned %08x\n", result));
return result;
@@ -244,19 +225,6 @@ uint32_t SetupTPM(int recovery_mode, int developer_mode,
RETURN_ON_FAILURE(TlclContinueSelfTest());
#endif
result = TlclAssertPhysicalPresence();
#ifdef TEGRA_SOFT_REBOOT_WORKAROUND
/*
* If soft_reset is true, the failure to assert PP is expected because the
* TPM is locked from a previous boot. In this case we will never execute
* the PhysicalPresenceCMDEnable below, but that's OK because this is a
* warm boot and at some point in the past we must have cold-booted with
* this firmware (one would hope), so that situation (TPM delivered with PP
* disabled) has already been resolved.
*/
if (soft_reset) {
result = TPM_SUCCESS;
}
#endif
if (result != TPM_SUCCESS) {
/* It is possible that the TPM was delivered with the physical presence
* command disabled. This tries enabling it, then tries asserting PP
@@ -484,18 +452,7 @@ uint32_t RollbackKernelLock(void) {
if (g_rollback_recovery_mode) {
return TPM_SUCCESS;
} else {
#ifdef TEGRA_SOFT_REBOOT_WORKAROUND
TPM_STCLEAR_FLAGS flags;
uint32_t result = TlclLockPhysicalPresence();
if (result == TPM_SUCCESS) {
return result;
}
RETURN_ON_FAILURE(TlclGetSTClearFlags(&flags));
/* Ignore PP locking failure if PP is already locked. */
return flags.physicalPresenceLock == 1 ? TPM_SUCCESS : result;
#else
return TlclLockPhysicalPresence();
#endif
}
}