On 03/02/2018 11:05 AM, Kevin O'Connor wrote:
On Tue, Feb 27, 2018 at 02:17:10PM -0500, Stephen Douthit wrote:
This is based on wait_startup() from the Linux tpm_tis driver.
Signed-off-by: Stephen Douthit stephend@silicom-usa.com Tested-by: Stephen Douthit stephend@silicom-usa.com
src/hw/tpm_drivers.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/src/hw/tpm_drivers.c b/src/hw/tpm_drivers.c index 13ad821..da8bb63 100644 --- a/src/hw/tpm_drivers.c +++ b/src/hw/tpm_drivers.c @@ -86,6 +86,11 @@ static u32 wait_reg8(u8* reg, u32 time, u8 mask, u8 expect) return rc; }
+static u32 tis_wait_access(u8 locty, u32 time, u8 mask, u8 expect) +{
- return wait_reg8(TIS_REG(locty, TIS_REG_ACCESS), time, mask, expect);
+}
- static u32 tis_wait_sts(u8 locty, u32 time, u8 mask, u8 expect) { return wait_reg8(TIS_REG(locty, TIS_REG_STS), time, mask, expect);
@@ -102,7 +107,13 @@ static u32 tis_probe(void) if (!CONFIG_TCGBIOS) return 0;
- u32 rc = 0;
- /* Wait for the interface to report it's ready */
- u32 rc = tis_wait_access(0, TIS_DEFAULT_TIMEOUT_A,
TIS_ACCESS_TPM_REG_VALID_STS,TIS_ACCESS_TPM_REG_VALID_STS);- if (rc)
return 0;Thanks. I was about to commit this when I noticed the above. In the case where tis_wait_access() fails due to a timeout, shouldn't tis_probe() return an error indicator instead of success?
tis_probe() returns 0 for no device, '1' for device present.
Take a look at the usage in tpmhw_probe(), or the comment on tis_probe() itself.
Thanks, Steve