Reland "2lib/2api: Deprecate vb2ex_ec_trusted()"

This reverts commit b9644352d7717d4f564be90aac6c41bef583d930.

Reason for revert: We can try another reland after the coreboot
CL https://review.coreboot.org/c/coreboot/+/58253 is
downstreamed and the guybrush psp_verstage.bin is signed again.

Original change's description:
> Revert "2lib/2api: Deprecate vb2ex_ec_trusted()"
>
> This reverts commit 7c73bb07fd3ca45ce650b993a9c6a5850ddb2707.
>
> Reason for revert: b:202258389
>
> Original change's description:
> > 2lib/2api: Deprecate vb2ex_ec_trusted()
> >
> > coreboot will support check the EC_IN_RW during verstage_main(), which
> > performs the equivalent tasks as vb2ex_ec_trusted().
> >
> > In the previous CL, we remove the check of vb2ex_ec_trusted(), so the
> > whole implementation of this function among vboot_reference and
> > depthcharge could be deprecated and removed.
> >
> > BUG=b:181931817
> > BRANCH=none
> > TEST=CC=x86_64-pc-linux-gnu-clang;
> >      make clean && make runtests
> > TEST=emerge coreboot vboot_reference depthcharge
> >
> > Cq-Depend: chromium:3139956
> > Signed-off-by: Hsuan Ting Chen <roccochen@chromium.org>
> > Change-Id: I4f592d7dec2480475762e1336791cbb34fa143ba
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3139539
> > Reviewed-by: Julius Werner <jwerner@chromium.org>
> > Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
>
> Bug: b:181931817
> Change-Id: Ia127ce89b7f9413db9fd6ca4561ad06efb36d7e1
> Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3211006
> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
> Commit-Queue: Bhanu Prakash Maiya <bhanumaiya@google.com>

Bug: b:181931817
Cq-Depend: chromium:3275254
Change-Id: I2c4db28b5800e5756f6f12b8bf69924f373a5c58
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3274698
Tested-by: Hsuan Ting Chen <roccochen@chromium.org>
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
Commit-Queue: Hsuan Ting Chen <roccochen@chromium.org>

3 files changed, 4 insertions, 18 deletions

diff --git a/firmware/2lib/2ec_sync.c b/firmware/2lib/2ec_sync.c
index 20490e08..e75313b4 100644
--- a/firmware/2lib/2ec_sync.c
+++ b/firmware/2lib/2ec_sync.c
@@ -160,10 +160,10 @@ static vb2_error_t check_ec_active(struct vb2_context *ctx)
 	struct vb2_shared_data *sd = vb2_get_sd(ctx);
 	int in_rw = 0;
 	/*
-	 * We don't use vb2ex_ec_trusted, which checks EC_IN_RW. It is
-	 * controlled by cr50 but on some platforms, cr50 can't know when a EC
-	 * resets. So, we trust what EC-RW says. If it lies it's in RO, we'll
-	 * flash RW while it's in RW.
+	 * We don't use VB2_CONTEXT_EC_TRUSTED, which checks if not EC_IN_RW.
+	 * It is controlled by cr50 but on some platforms, cr50 can't know when
+	 * a EC resets. So, we trust what EC-RW says. If it lies it's in RO,
+	 * we'll flash RW while it's in RW.
 	 */
 	/* If we couldn't determine where the EC was, reboot to recovery. */
 	VB2_TRY(vb2ex_ec_running_rw(&in_rw),
diff --git a/firmware/2lib/2stub.c b/firmware/2lib/2stub.c
index d53d472f..da754ad4 100644
--- a/firmware/2lib/2stub.c
+++ b/firmware/2lib/2stub.c
@@ -75,12 +75,6 @@ vb2_error_t vb2ex_tpm_set_mode(enum vb2_tpm_mode mode_val)
 /* auxfw and EC-related stubs */
 
 __attribute__((weak))
-int vb2ex_ec_trusted(void)
-{
-	return 1;
-}
-
-__attribute__((weak))
 vb2_error_t vb2ex_ec_running_rw(int *in_rw)
 {
 	*in_rw = 0;
diff --git a/firmware/2lib/include/2api.h b/firmware/2lib/include/2api.h
index 67b8dfac..8966999d 100644
--- a/firmware/2lib/include/2api.h
+++ b/firmware/2lib/include/2api.h
@@ -1303,14 +1303,6 @@ enum vb2_firmware_selection {
 vb2_error_t vb2api_ec_sync(struct vb2_context *ctx);
 
 /**
- * This is called only if the system implements a keyboard-based (virtual)
- * developer switch. It must return true only if the system has an embedded
- * controller which is provably running in its RO firmware at the time the
- * function is called.
- */
-int vb2ex_ec_trusted(void);
-
-/**
  * Check if the EC is currently running rewritable code.
  *
  * If the EC is in RO code, sets *in_rw=0.