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authorSimon Glass <sjg@chromium.org>2022-04-30 00:56:52 -0600
committerTom Rini <trini@konsulko.com>2022-05-02 09:58:13 -0400
commitf86ca5ad8f780d306e79d49ffe4f5cf1edef37b9 (patch)
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Introduce Verifying Program Loader (VPL)
Add support for VPL, a new phase of U-Boot. This runs after TPL. It is responsible for selecting which SPL binary to run, based on a verified-boot process. Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'doc')
-rw-r--r--doc/develop/spl.rst7
1 files changed, 6 insertions, 1 deletions
diff --git a/doc/develop/spl.rst b/doc/develop/spl.rst
index 1059b2f..aec7b56 100644
--- a/doc/develop/spl.rst
+++ b/doc/develop/spl.rst
@@ -83,7 +83,12 @@ U-Boot Phases
U-Boot boots through the following phases:
TPL
- Very early init, as tiny as possible. This loads SPL.
+ Very early init, as tiny as possible. This loads SPL (or VPL if enabled).
+
+VPL
+ Optional verification step, which can select one of several SPL binaries,
+ if A/B verified boot is enabled. Implementation of the VPL logic is
+ work-in-progress. For now it just boots into SPL.
SPL
Secondary program loader. Sets up SDRAM and loads U-Boot proper. It may also