On 3/3/23 20:25, Eddie James wrote:
Briefly describe the feature and specify the requirements.Signed-off-by: Eddie James <eaja...@linux.ibm.com> Reviewed-by: Simon Glass <s...@chromium.org> --- doc/usage/index.rst | 1 + doc/usage/measured_boot.rst | 23 +++++++++++++++++++++++ 2 files changed, 24 insertions(+) create mode 100644 doc/usage/measured_boot.rst diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 840c20c934..1cb6988d8a 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -12,6 +12,7 @@ Use U-Boot partitions cmdline semihosting + measured_boot Shell commands -------------- diff --git a/doc/usage/measured_boot.rst b/doc/usage/measured_boot.rst new file mode 100644 index 0000000000..8357b1f480 --- /dev/null +++ b/doc/usage/measured_boot.rst @@ -0,0 +1,23 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +Measured Boot +===================== + +U-Boot can perform a measured boot, the process of hashing various components
This text is misleading: U-Boot does not perform measured boot. U-Boot performing measured boot would imply that it checks if the incoming values of the PCRs match expected values. This is not what is done with this series. U-Boot assists measured boot by extending PCRs and providing an event log. Best regards Heinrich
+of the boot process, extending the results in the TPM and logging the +component's measurement in memory for the operating system to consume. + +Requirements +--------------------- + +* A hardware TPM 2.0 supported by the U-Boot drivers +* CONFIG_TPM=y +* CONFIG_MEASURED_BOOT=y +* Device-tree configuration of the TPM device to specify the memory area + for event logging. The TPM device node must either contain a phandle to + a reserved memory region or "linux,sml-base" and "linux,sml-size" + indicating the address and size of the memory region. An example can be + found in arch/sandbox/dts/test.dts +* The operating system must also be configured to use the memory regions + specified in the U-Boot device-tree in order to make use of the event + log.
