Merge branch '2022-05-02-add-verifying-program-loader'

To quote the author:

U-Boot provides a verified-boot feature based around FIT, but there is
no standard way of implementing it for a board. At present the various
required pieces must be built up separately, to produce a working
implementation. In particular, there is no built-in support for selecting
A/B boot or recovery mode.

This series introduces VPL, a verified program loader phase for U-Boot.
Its purpose is to run the verified-boot process and decide which SPL
binary should be run. It is critical that this decision happens before
SPL runs, since SPL sets up SDRAM and we need to be able to update the
SDRAM-init code in the field.

Adding VPL into the boot flow provides a standard place to implement
verified boot. This series includes the phase itself, some useful Kconfig
options and a sandbox_vpl build for sandbox. No verfied-boot support is
provided in this series.

Most of the patches in this series are fixes and improvements to docs and
various Kconfig conditions for SPL.

1 files changed, 22 insertions, 3 deletions

diff --git a/common/spl/spl.c b/common/spl/spl.c
index c9750ee163..c8c463f80b 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -61,6 +61,11 @@ binman_sym_declare(ulong, u_boot_spl, image_pos);
 binman_sym_declare(ulong, u_boot_spl, size);
 #endif
 
+#ifdef CONFIG_VPL
+binman_sym_declare(ulong, u_boot_vpl, image_pos);
+binman_sym_declare(ulong, u_boot_vpl, size);
+#endif
+
 /* Define board data structure */
 static struct bd_info bdata __attribute__ ((section(".data")));
 
@@ -146,14 +151,22 @@ void spl_fixup_fdt(void *fdt_blob)
 #if CONFIG_IS_ENABLED(BINMAN_SYMBOLS)
 ulong spl_get_image_pos(void)
 {
-	return spl_phase() == PHASE_TPL ?
+#ifdef CONFIG_VPL
+	if (spl_next_phase() == PHASE_VPL)
+		return binman_sym(ulong, u_boot_vpl, image_pos);
+#endif
+	return spl_next_phase() == PHASE_SPL ?
 		binman_sym(ulong, u_boot_spl, image_pos) :
 		binman_sym(ulong, u_boot_any, image_pos);
 }
 
 ulong spl_get_image_size(void)
 {
-	return spl_phase() == PHASE_TPL ?
+#ifdef CONFIG_VPL
+	if (spl_next_phase() == PHASE_VPL)
+		return binman_sym(ulong, u_boot_vpl, size);
+#endif
+	return spl_next_phase() == PHASE_SPL ?
 		binman_sym(ulong, u_boot_spl, size) :
 		binman_sym(ulong, u_boot_any, size);
 }
@@ -161,7 +174,11 @@ ulong spl_get_image_size(void)
 
 ulong spl_get_image_text_base(void)
 {
-	return spl_phase() == PHASE_TPL ? CONFIG_SPL_TEXT_BASE :
+#ifdef CONFIG_VPL
+	if (spl_next_phase() == PHASE_VPL)
+		return CONFIG_VPL_TEXT_BASE;
+#endif
+	return spl_next_phase() == PHASE_SPL ? CONFIG_SPL_TEXT_BASE :
 		CONFIG_SYS_TEXT_BASE;
 }
 
@@ -466,6 +483,8 @@ static enum bootstage_id get_bootstage_id(bool start)
 
 	if (IS_ENABLED(CONFIG_TPL_BUILD) && phase == PHASE_TPL)
 		return start ? BOOTSTAGE_ID_START_TPL : BOOTSTAGE_ID_END_TPL;
+	else if (IS_ENABLED(CONFIG_VPL_BUILD) && phase == PHASE_VPL)
+		return start ? BOOTSTAGE_ID_START_VPL : BOOTSTAGE_ID_END_VPL;
 	else
 		return start ? BOOTSTAGE_ID_START_SPL : BOOTSTAGE_ID_END_SPL;
 }