tpm: provide explicit tpm register access
An issue was observed using a specific vendor's TPM in that it
chokes on access to registers that are not explicitly defined in the
PC client specification. The previous driver used generic access
functions for reading and writing registers. However, issues come
to play when reading from the status register. It read it as a 32-bit
value, but that read address 0x1b which is not defined in the spec.
Instead of using generic access functions for the tpm registers
provide explicit ones. To that end provide more high level wrapper
functions to perform the semantic access required.
BUG=chrome-os-partner:20565
BRANCH=None
TEST=Built and booted on bolt. TPM access works through coreboot.
Change-Id: I781b31723f819e1387d7aa25512c83780ea0877f
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/63243
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
1 file changed
